RealVideo

November 15, 2024 by Thor 1 Comment

For #WDPD24 and PRONOM Hackathon week this year, I want to find some older formats listed which did not have a signature. There is a list to choose from, but I wanted to find something I hadn’t worked on before. I came across two entries for Real Video:

PUID	Name	Extension
fmt/204	RealVideo Clip	rv
x-fmt/277	Real Video	rv

I was familiar with Real Media and Real Audio, but had yet to come across any RealVideo with the RV extension. I thought it would be easy to find some references and samples, but that was not the case. I assume PRONOM originally added these based on MIME types available.

Real or RealNetworks is/was an Internet media company who jumped on the rapidly growing World Wide Web in 1995 to become a leader in Internet Media Delivery. Their initial offerings mainly focused on audio streaming and they accomplished all of this by providing free players and web browser extensions to make it easy to serve up a website with streaming media everyone could enjoy. Later adding video streaming optimized for the slower dialup and connections of the day. They used codecs based on common technology like H.263 and H.264, but used then to make their own proprietary codecs identified through FourCC codes, RV10-RV60.

So thought it would be easy to find a reference to the RV extension, I quickly discovered it wasn’t. Looking at the Wikipedia page on RealVideo, I found no reference to the RV extension. RV is an abbreviation for RealVideo, right? Well, I ended up finding a reference in the RealAudio page under file extensions. Ok, First clue to the existence of the RV extension. The page references RV as being used for video only files and was used by the flagship encoder (RealProducer).

RealProducer was the tool for creating the streaming audio and video formats that could then be used for your website or streaming platform. The RealProducer software came in a Basic version, which was free, and the Plus or Pro version, which was not free and provided more options. The first version of RealProducer to make video files was version 4. I was able to find a copy of the encoder and installed it under a Windows 95 emulator. To my surprise it only saved to the RealMedia RM file format. This format is well known and identified with PRONOM as x-fmt/190 also documented at the LoC.

This was the same with RealProducer 5, 7, 8, 9, and 10 that I was able to try. All made no mention of the RV extension. I was starting to feel this format didn’t exist or that some decided to use the RV extension on their own. Searches on Google yielded a couple results, mostly from users who had found a few files on their older discs and wanted to migrate them to something newer. I was able to find one example, one user shared, but it had the same header as the RealMedia format. The clue was in the file.

hexdump -C ambush_abb.rv
00000000  2e 52 4d 46 00 00 00 12  00 01 00 00 00 00 00 00  |.RMF............|
00000010  00 07 50 52 4f 50 00 00  00 32 00 00 00 03 6e e8  |..PROP...2....n.|
00000020  00 03 6e e8 00 00 03 e0  00 00 01 b3 00 00 6a 6f  |..n...........jo|
00000030  00 06 80 fa 00 00 08 b5  00 ba 41 73 00 00 03 55  |..........As...U|
00000040  00 03 00 09 43 4f 4e 54  00 00 00 40 00 00 00 00  |....CONT...@....|
00000050  00 00 00 08 28 43 29 20  32 30 30 35 00 26 00 00  |....(C) 2005.&..|
00000060  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000270  00 09 61 75 64 69 6f 4d  6f 64 65 00 00 00 02 00  |..audioMode.....|
00000280  06 76 6f 69 63 65 00 00  00 00 2d 00 00 0d 43 72  |.voice....-...Cr|
00000290  65 61 74 69 6f 6e 20 44  61 74 65 00 00 00 02 00  |eation Date.....|
000002a0  13 39 2f 32 30 2f 32 30  30 36 20 31 34 3a 30 37  |.9/20/2006 14:07|
000002b0  3a 30 38 00 00 00 00 53  00 00 0c 47 65 6e 65 72  |:08....S...Gener|
000002c0  61 74 65 64 20 42 79 00  00 00 02 00 3a 52 65 61  |ated By.....:Rea|
000002d0  6c 50 72 6f 64 75 63 65  72 28 52 29 20 42 61 73  |lProducer(R) Bas|
000002e0  69 63 20 31 31 2e 30 20  66 6f 72 20 57 69 6e 64  |ic 11.0 for Wind|
000002f0  6f 77 73 2c 20 42 75 69  6c 64 20 31 31 2e 30 2e  |ows, Build 11.0.|
00000300  30 2e 32 30 30 39 00 00  00 00 31 00 00 11 4d 6f  |0.2009....1...Mo|
00000310  64 69 66 69 63 61 74 69  6f 6e 20 44 61 74 65 00  |dification Date.|
00000320  00 00 02 00 13 39 2f 32  30 2f 32 30 30 36 20 31  |.....9/20/2006 1|
00000330  34 3a 30 37 3a 30 38 00  00 00 00 1d 00 00 09 76  |4:07:08........v|
00000340  69 64 65 6f 4d 6f 64 65  00 00 00 02 00 07 6e 6f  |ideoMode......no|
00000350  72 6d 61 6c 00 44 41 54  41 00 ba 3e 1e 00 00 00  |rmal.DATA..>....|

RealProducer Basic 11 for Windows. The Wikipedia article did hint at this by saying “the latest version of RealProducer reverted to using .ra for audio only files and began using .rv for video files with or without audio.” Why would they use the RM extension for so long, then revert to a different extension with a later version? I found more in the User Manual for version 11.

• .rv – RealVideo
    RealProducer uses the .rv file extension if the input is video-only or video-with-audio. You can also select the .rm file extension for video content.
    Tip: Using the .rv file extension helps search engines identify the file as a RealVideo clip.

• .rm – RealAudio or RealVideo
    RealProducer chooses the .rm file extension if it cannot determine the content of the input clip. You can use .rm file extension for any RealAudio or RealVideo clip, except for variable bit-rate clips.

Ok, so a few things to learn from this. One is the RV extension was used as the default for version 11 as they wanted search engines to identify them as a RealVideo clip. Second thing we learned is there is no difference between the two placeholders in PRONOM, one being a RealVideo file and the other being a RealVideo Clip. We don’t need both.

Now, is there any difference between an RV and RM file?

hexdump -C Producer11-01.rv | head
00000000  2e 52 4d 46 00 00 00 12  00 01 00 00 00 00 00 00  |.RMF............|
00000010  00 07 50 52 4f 50 00 00  00 32 00 00 00 03 6e e8  |..PROP...2....n.|
00000020  00 03 6e e8 00 00 03 e0  00 00 01 c7 00 00 01 66  |..n............f|
00000030  00 00 1b 57 00 00 07 41  00 02 91 0a 00 00 03 5e  |...W...A.......^|
00000040  00 03 00 09 43 4f 4e 54  00 00 00 40 00 00 00 00  |....CONT...@....|
00000050  00 00 00 08 28 43 29 20  32 30 30 35 00 26 00 00  |....(C) 2005.&..|
00000060  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000080  00 00 00 00 4d 44 50 52  00 00 00 70 00 00 00 00  |....MDPR...p....|
00000090  00 02 c2 a4 00 02 c2 a4  00 00 03 e0 00 00 01 9f  |................|

hexdump -C Producer11-01.rm | head
00000000  2e 52 4d 46 00 00 00 12  00 01 00 00 00 00 00 00  |.RMF............|
00000010  00 07 50 52 4f 50 00 00  00 32 00 00 00 03 6e e8  |..PROP...2....n.|
00000020  00 03 6e e8 00 00 03 e0  00 00 01 a4 00 00 01 64  |..n............d|
00000030  00 00 1b 57 00 00 05 a4  00 02 5c 35 00 00 03 5e  |...W......\5...^|
00000040  00 03 00 09 43 4f 4e 54  00 00 00 40 00 00 00 00  |....CONT...@....|
00000050  00 00 00 08 28 43 29 20  32 30 30 35 00 26 00 00  |....(C) 2005.&..|
00000060  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000080  00 00 00 00 4d 44 50 52  00 00 00 70 00 00 00 00  |....MDPR...p....|
00000090  00 02 c2 a4 00 02 c2 a4  00 00 03 e0 00 00 01 a4  |................|

They both look very similar to me. Aside from a few bytes, they are practically identical. Lets see what MediaInfo has to say.

mediainfo Producer11-01.rv
General
Complete name                            : Producer11-01.rv
Format                                   : RealMedia
File size                                : 164 KiB
Duration                                 : 6 s 999 ms
Overall bit rate                         : 225 kb/s
Frame rate                               : 24.000 FPS
Copyright                                : (C) 2005
FileExtension_Invalid                    : rm rmvb ra

Video
ID                                       : 0
Format                                   : RealVideo 4
Codec ID                                 : RV40
Codec ID/Info                            : Based on AVC (H.264), Real Player 9
Duration                                 : 6 s 999 ms
Bit rate                                 : 181 kb/s
Width                                    : 640 pixels
Height                                   : 424 pixels
Display aspect ratio                     : 3:2
Frame rate                               : 24.000 FPS
Bits/(Pixel*Frame)                       : 0.028
Stream size                              : 155 KiB (94%)

Audio
ID                                       : 1
Format                                   : Cooker
Codec ID                                 : cook
Codec ID/Info                            : Based on G.722.1, Real Player 6
Duration                                 : 7 s 429 ms
Bit rate                                 : 44.1 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 44.1 kHz
Bit depth                                : 16 bits
Stream size                              : 40.0 KiB (24%)

mediainfo Producer11-01.rm
General
Complete name                            : Producer11-01.rm
Format                                   : RealMedia
File size                                : 151 KiB
Duration                                 : 6 s 999 ms
Overall bit rate                         : 225 kb/s
Frame rate                               : 24.000 FPS
Copyright                                : (C) 2005

Video
ID                                       : 0
Format                                   : RealVideo 4
Codec ID                                 : RV40
Codec ID/Info                            : Based on AVC (H.264), Real Player 9
Duration                                 : 6 s 999 ms
Bit rate                                 : 181 kb/s
Width                                    : 640 pixels
Height                                   : 424 pixels
Display aspect ratio                     : 3:2
Frame rate                               : 24.000 FPS
Bits/(Pixel*Frame)                       : 0.028
Stream size                              : 155 KiB

Audio
ID                                       : 1
Format                                   : Cooker
Codec ID                                 : cook
Codec ID/Info                            : Based on G.722.1, Real Player 6
Bit rate                                 : 44.1 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 44.1 kHz
Bit depth                                : 16 bits

Other than the RV file having a invalid file extension, they both identify as a RealMedia file and have identical properties. So it seems the RV file is really no different than the RM file. I think the best course of action for PRONOM is to deprecate these two RV PUID’s and just ad RV as an acceptable extension for the RealMedia format.

To add to the evidence, here is the output from ffprobe:

Input #0, rm, from 'Producer11-01.rm':
  Metadata:
    copyright       : (C) 2005
    comment         : 
    ASMRuleBook     : #($Bandwidth >= 0),Stream1Bandwidth = 44100, Stream0Bandwidth = 180900;
    Audiences       : 256k DSL or Cable;
    audioMode       : music
    Creation Date   : 11/12/2024 20:28:55
    Generated By    : RealProducer(R) Plus 11.1 for Windows, Build 11.1.0.2676
    Modification Date: 11/12/2024 20:28:55
    videoMode       : normal
  Duration: 00:00:07.00, start: 0.000000, bitrate: 176 kb/s
  Stream #0:0: Video: rv40 (RV40 / 0x30345652), yuv420p, 640x424, 180 kb/s, 24 fps, 24 tbr, 1k tbn
  Stream #0:1: Audio: cook (cook / 0x6B6F6F63), 44100 Hz, stereo, fltp, 44 kb/s

Input #0, rm, from 'Producer11-01.rv':
  Metadata:
    copyright       : (C) 2005
    comment         : 
    ASMRuleBook     : #($Bandwidth >= 0),Stream1Bandwidth = 44100, Stream0Bandwidth = 180900;
    Audiences       : 256k DSL or Cable;
    audioMode       : music
    Creation Date   : 11/12/2024 20:28:16
    Generated By    : RealProducer(R) Plus 11.1 for Windows, Build 11.1.0.2676
    Modification Date: 11/12/2024 20:28:16
    videoMode       : normal
  Duration: 00:00:07.43, start: 0.000000, bitrate: 181 kb/s
  Stream #0:0: Video: rv40 (RV40 / 0x30345652), yuv420p, 640x424, 180 kb/s, 24 fps, 24 tbr, 1k tbn
  Stream #0:1: Audio: cook (cook / 0x6B6F6F63), 44100 Hz, stereo, fltp, 44 kb/s

But wait, there are a couple formats we could add which are related to RealProducer. RealProducer used a few other formats to manage projects and other metadata for streaming. They include:

.RP RealPix Image
.RT RealText
.RPAD RealProducer Audience File
.RPJF RealProducer Job File
.RPSD RealProducer Server Destination
.RMHD RealMediaHD file
.RAM Playlist
.RPM Embedded RAM

File Type	Extension	MIME Type
Ram	.ram	audio/x-pn-realaudio
Embedded Ram	.rpm	audio/x-pn-realaudio-plugin
SMIL	.smil and .smi	application/smil
RealAudio	.ra	audio/x-pn-realaudio
RealVideo	.rm	application/x-pn-realmedia
Flash	.swf	application/x-shockwave-flash
RealPix	.rp	image/vnd.rn-realpix
RealText	.rt	text/vnd.rn-realtext

https://web.archive.org/web/20120513203726/http://service.real.com/help/library/guides/production8/htmfiles/server.htm

Don’t get excited, the RealPix Image format really isn’t an image, it is simply an XML file with all the details of an image or group of images. Pretty boring. It was however a big thing in the day, even got a full guide written up for the process. “All information in the file occurs between an opening <imfl> tag and a closing </imfl> tag. This is the only tag that uses an end tag.” This format was the topic of discussion as malicious code could be in the RP file and executed just by having someone load your webpage. IMFL is obviously an acronym, but none of the documents I could find tells me what it stands for, so I did what everyone does now, I asked ChatGPT.

The RealPix format by RealNetworks, which was used for interactive multimedia content, indeed utilized IMFL as its tagged format. IMFL stands for “Interleaved Media File Language.” This markup was particularly designed to handle multimedia presentations, allowing the synchronization of images, audio, and video in a slideshow-style format. It used XML-like syntax where elements like <imfl>, <head>, and <fadein/> defined media objects, transitions, and their timing. Key components included attributes for positioning, color, and animation effects, making RealPix a flexible format for creating multimedia sequences compatible with RealPlayer.

For technical details, the RealPix format closely resembles SMIL (Synchronized Multimedia Integration Language) and supports strict tag closure and case sensitivity. This means all tags and attribute names must be lowercase, and attributes must be in double quotes, as seen in SMIL and RealSystem G2 markup, RealNetworks’ broader multimedia framework.

When I asked for a source, it could not give me one. So not sure if it is the correct answer, but it seems to fit. Here are some samples of RP, RT and SMIL files.

For RealText with the RT extension, we find a similar tagged text. This format is used to provide text presentations to go along with Images, Audio, or Video. The tagged text then describes when and how the text is displayed. This is all done in a player window, therefore the root tag of these RT documents starts and ends with <window>. I guess these could be considered a subtitle format for streaming media.

The SMIL files is interesting, it is known standard, but in many cases, does not have an XML declaration, therefore not identified by current PRONOM. They are used to link everything together. I might suggest a variant of the SMIL format to not have the XML declaration to identify these formats correctly.

<smil>
 <body>
  <par>
   <textstream src=”rtsp://realserver.company.com/mary.rt”/>
   <video src=”rtsp://realserver.company.com/mary.rm”/>
  </par>
 </body>
</smil>

The .RPAD RealProducer Audience File, .RPJF RealProducer Job File, .RPSD RealProducer Server Destination are all XML files for managing some of the configuration found in the RealProducer software.

cat 56k\ Dial-up.rpad
<?xml version="1.0" encoding="UTF-8"?>
<audience xmlns="http://ns.real.com/tools/audience.2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://ns.real.com/tools/audience.2.0 http://ns.real.com/tools/audience.2.0.xsd">
  <avgBitrate type="uint">34000</avgBitrate>
  <maxBitrate type="uint">68000</maxBitrate>
  <streams>

cat RealProducer11-01.rpjf
<?xml version="1.0" encoding="UTF-8"?>
<job xmlns="http://ns.real.com/tools/job.2.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://ns.real.com/tools/job.2.0 http://ns.real.com/tools/job.2.0.xsd">
  <enableTwoPass type="bool">true</enableTwoPass>
  <clipInfo>

cat Multicast\ Push\ Server.rpsd
<?xml version="1.0" encoding="UTF-8"?>
<destination xsi:type="pushServer" xmlns="http://ns.real.com/tools/server.2.0"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://ns.real.com/tools/server.2.0 http://ns.real.com/tools/server.2.0.xsd">
  <pluginName type="string">rn-server-rbs</pluginName>

Those three formats should be easy enough, especially if we look for Namespace urls.

The RAM and RPM formats are simply text files with a URL. You can find some samples here and here.

An RM and RV file are the same format as the RMVB file but just with a variable bitrate. Later on a new format was used to improve the quality of video. This format has the extension RMHD, referring to RealMedia HD. Let’s take a look.

hexdump -C DSC_0009.rmhd | head
00000000  2e 52 4d 50 00 00 00 12  00 01 00 00 00 00 00 00  |.RMP............|
00000010  00 07 50 52 4f 50 00 00  00 36 00 02 00 04 f7 33  |..PROP...6.....3|
00000020  00 04 f7 33 00 00 11 bd  00 00 02 5d 00 00 01 d2  |...3.......]....|
00000030  00 00 1b 2e 00 00 00 00  00 00 00 00 00 04 65 68  |..............eh|
00000040  00 00 01 6f 00 02 00 03  43 4f 4e 54 00 00 00 12  |...o....CONT....|
00000050  00 00 00 00 00 00 00 00  00 00 4d 44 50 52 00 00  |..........MDPR..|
00000060  00 76 00 00 00 00 00 03  24 64 00 03 24 64 00 00  |.v......$d..$d..|
00000070  11 bd 00 00 04 2a 00 00  00 00 00 00 00 00 00 00  |.....*..........|
00000080  1b 2e 0c 56 69 64 65 6f  20 53 74 72 65 61 6d 14  |...Video Stream.|
00000090  76 69 64 65 6f 2f 78 2d  70 6e 2d 72 65 61 6c 76  |video/x-pn-realv|

The format looks very similar, but has the magic header of .RMP instead of .RMF. MediaInfo and FFProbe are unaware of the format. The software mentions a RV11 codec which is confusing as the codecs went from RV10-RV60.

Phew, that was a lot considering the two formats I tried to research came up the same as an existing format. There are probably others I have missed. I did see a reference to an RMX format which seems to be an encrypted RM file. The header is the same so it will identify as a RealMedia file, but with the wrong extension. Let me know if you come across any. I have some samples of the formats mentioned here, plus a proposal of new signatures on my Github repository.

ATRAC

September 6, 2024 by Thor Leave a comment

The year was 2001 and I found myself in need of an audio player and recorder. I had been burning CD’s for a few years, making mixed CD’s was fun and convenient, but I needed more flexibility. After some research I decided on a device that was super popular outside the United States, but was gaining some loyal fans.

This MZ-G750 MiniDisc device could record in a standard high quality mode through RCA, optical digital cable, and an optional microphone in mini-plug. This model also had the LP2 and LP4 modes which compressed higher, but could record up to 320 minutes on one MD disc.

Sony accomplished this by using a propriety compression codec called ATRAC, or Adaptive TRansform Acoustic Coding. This compression format was used with the MiniDisc and other Sony devices like the the flash memory Walkman’s sold later.

I recorded and stored a lot of music on the few disc’s I purchased over the next year, but as you may have surmised, the iPod came out later that year. I waited a bit but eventually purchased the updated 10GB model and the MiniDisc only was used to make a few recordings over the next little while.

As good as the MiniDisc is, the model I owned could record in a digital format, but lacked the connections to transfer the audio to a computer unless you used the optical cable and captured in real time to a computer with an optical input. This was by design, even when they put USB ports on later models, the software only allowed sending audio to the MiniDisc, but not back from the device.

A few years back I heard of some work the community has done to bring MiniDisc’s back from shadows. Now there is a thriving market and some models can cost a pretty penny. With that came some great tools and the ability to copy from the device back to the computer. The only problem, my device lacks a USB port. I kept my eye out for a “good” deal on a NetMD MiniDisc device. It took some time, but I am happy to report I am now the proud owner of a MZ-N420D.

With a new USB capable NetMD in hand, lets take a look at the different ATRAC formats!

The most common ATRAC formats are the ATRAC3 versions which generally have the extension OMA or OMG. But let’s start with ATRAC1, the format used on my earlier MiniDisc device when captured in Standard Mode. Using the amazing https://webmd.pro/ tool, I was able to connect my new device and “archive” my disc.

hexdump -C Test1.aea | head
00000000  00 08 00 00 54 65 73 74  31 00 00 00 00 00 00 00  |....Test1.......|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000100  00 00 00 00 1e 01 00 00  02 00 00 00 00 00 00 00  |................|
00000110  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000b50  0c a0 45 57 54 44 32 35  41 44 22 34 32 24 13 23  |..EWTD25AD"42$.#|
00000b60  32 23 22 12 11 11 11 11  76 18 69 75 f8 63 69 a7  |2#".....v.iu.ci.|
00000b70  a4 5d 46 22 45 36 1f 59  55 9d 41 55 19 51 45 17  |.]F"E6.YU.AU.QE.|
00000b80  45 14 55 38 c2 cb 2c b2  88 26 fd b2 17 b3 f0 0f  |E.U8..,..&......|

ffprobe -i Test1.aea
[aea @ 0x7fc5e6c04fc0] Estimating duration from bitrate, this may be inaccurate
Input #0, aea, from 'Test1.aea':
  Duration: 00:00:01.63, bitrate: 302 kb/s
  Stream #0:0: Audio: atrac1, 44100 Hz, stereo, fltp, 292 kb/s

ATRAC1 files can have the AEA extension, which ffmpeg can decode, but MediaInfo doesn’t appear to have added the support. According to the decoder the magic numbers for the ATRAC1 format are “Magic is ‘00 08 00 00‘ in little-endian”. This pattern matches my files, but the recent addition PRONOM fmt/1968 doesn’t match all the samples I have.

The magic numbers are too simple to be the only pattern used in a signature. The Track title follows the magic numbers but are not static. Then there are quite a bit of zero bytes, like a lot. All the samples I have seem to have some data around the 260 offset, then more zero bytes until around 2400 to 2800 byte offset range. I scanned all the samples I have through Tridscan, and it looks like the only bytes in common are the magic header, lots of zero’s, and a few strings.

	<GlobalStrings>
		<String>ED33</String>
		<String>EUD3</String>
		<String>FTDC</String>
		<String>T322</String>
		<String>TC32</String>
		<String>TC43</String>
		<String>UC22</String>
		<String>UED3</String>
		<String>VD33</String>
		<String>VETC</String>
		<String>WEDD</String>
	</GlobalStrings>

The ffmpeg libavformat code does tell us at byte 264 there will be a 01 or 02 which indicates channels. 44.1 kHz is assumed and the bitrate is calculated from a constant by how many channels, so not much else to identify common patterns. More testing needed.

ATRAC3 is what allowed my original MiniDisc to record in LP2 and LP4, extending the recording time. This format was also how some DRM was added to the device and computer to allow for some checking-in and checking-out of files, but to control their use. This was done with Desktop software from Sony, originally in the form of the title SonicStage, later incorporating OpenMG to manage the DRM. I used SonicStage to encode some audio into OMG and OMA formats.

OpenMG format files

These are audio files which have been converted to ATRAC3 format and encrypted in OpenMG format, which is the copyright protection technology for audio contents specific to OpenMG (with the extension .omg).

hexdump -C 01-Untitled.omg | head
00000000  30 80 30 80 06 07 66 6f  70 65 6e 4d 47 02 02 03  |0.0...fopenMG...|
00000010  eb 04 14 01 0f 50 00 00  04 00 00 00 ba d0 90 49  |.....P.........I|
00000020  3d 7f 61 7b 91 c4 30 06  02 67 01 02 02 3f 00 06  |=.a{..0..g...?..|
00000030  02 68 01 02 04 00 59 47  80 02 01 00 02 03 02 03  |.h....YG........|
00000040  a0 02 02 01 80 02 01 00  00 00 04 08 f5 94 79 c9  |..............y.|
00000050  6b 78 75 22 04 84 00 59  5e 30 83 0b 71 39 e3 e8  |kxu"...Y^0..q9..|
00000060  27 29 00 00 00 00 00 00  00 00 26 e2 65 d0 de e0  |')........&.e...|
00000070  69 19 73 45 1c c4 3b 36  8d 02 3b 72 bd eb 84 df  |i.sE..;6..;r....|
00000080  cd 20 4e 43 d3 e3 23 8a  3f 9e df 80 f1 86 d1 aa  |. NC..#.?.......|
00000090  2b 93 bf 09 59 0d d6 8f  78 5d 45 3a 9f d8 79 8b  |+...Y...x]E:..y.|

ffprobe -i /01-Untitled.omg 
[oma @ 0x7fed2440e980] Format oma detected only with low score of 1, misdetection possible!
[oma @ 0x7fed2440e980] Couldn't find the EA3 header !
/01-Untitled.omg: Invalid data found when processing input

The good news is there appears to be a standard header for the OMG format, but ffmpeg assumes they are OMA files. Turns out OMG was the original form of the format, but was replaced with OMA starting with SonicStage v2.1.

hexdump -C 01-Untitled.oma | head
00000000  65 61 33 03 00 00 00 00  17 76 54 49 54 32 00 00  |ea3......vTIT2..|
00000010  00 17 00 00 02 00 55 00  6e 00 74 00 69 00 74 00  |......U.n.t.i.t.|
00000020  6c 00 65 00 64 00 28 00  31 00 29 54 41 4c 42 00  |l.e.d.(.1.)TALB.|
00000030  00 00 11 00 00 02 00 55  00 6e 00 74 00 69 00 74  |.......U.n.t.i.t|
00000040  00 6c 00 65 00 64 54 58  58 58 00 00 00 17 00 00  |.l.e.dTXXX......|
00000050  02 00 4f 00 4d 00 47 00  5f 00 54 00 52 00 41 00  |..O.M.G._.T.R.A.|
00000060  43 00 4b 00 00 00 31 54  58 58 58 00 00 00 25 00  |C.K...1TXXX...%.|
00000070  00 02 00 4f 00 4d 00 47  00 5f 00 41 00 4c 00 42  |...O.M.G._.A.L.B|
00000080  00 4d 00 53 00 00 00 55  00 6e 00 74 00 69 00 74  |.M.S...U.n.t.i.t|
00000090  00 6c 00 65 00 64 54 58  58 58 00 00 00 23 00 00  |.l.e.dTXXX...#..|
*
00000c00  45 41 33 03 00 60 ff 80  00 00 00 00 01 0f 50 00  |EA3..`........P.|
00000c10  00 04 00 00 00 60 8a 07  e3 0a c9 91 63 46 c6 bc  |.....`......cF..|
00000c20  22 52 03 76 00 05 66 48  00 00 3b 86 00 00 00 00  |"R.v..fH..;.....|
00000c30  00 00 20 30 00 00 00 00  00 00 00 00 00 00 00 00  |.. 0............|
00000c40  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

ffprobe -i 01-Untitled.oma
Input #0, oma, from '01-Untitled.oma':
  Metadata:
    title           : Untitled(1)
    album           : Untitled
    OMG_TRACK       : 1
    OMG_ALBMS       : Untitled
    OMG_ASGTM       : 2366000
    OMG_TIT2S       : Untitled(1)
    TLEN            : 353000
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #0:0: Audio: atrac3al ([34][0][0][0] / 0x0022), 44100 Hz, stereo, fltp

We learned from trying an OMG file in ffprobe that ffmpeg is looking for EA3 header, which is found in this OMA file. Both of these formats should have a nice header to work from for a signature. In fact there has already been a request and signature submitted for the OMA format. Mine are slightly different, but only takes a small tweak to work with all my samples. Also, it seems the extension AA3 was used for awhile before settling on OMA. OMA can have a few different types:

ffprobe -i 02-Untitled.oma 
[oma @ 0x7fbc7ef047c0] Estimating duration from bitrate, this may be inaccurate
Input #0, oma, from '/Star Trek/02-Untitled.oma':
  Metadata:
    title           : Untitled(2)
    album           : Star Trek
    OMG_TRACK       : 2
    OMG_ALBMS       : Star Trek
    OMG_ASGTM       : 2366000
    OMG_TIT2S       : Untitled(2)
    TLEN            : 27000
  Duration: 00:00:27.21, start: 0.000000, bitrate: 193 kb/s
  Stream #0:0: Audio: atrac3p ([1][0][0][0] / 0x0001), 44100 Hz, stereo, fltp, 192 kb/s

I’ll leave the technical properties to be handled by tools more suited for parsing the format like ffmpeg. Maybe MediaInfo could have the formats added, but until then, it might be best to simply identify the main format. I am also aware of some later additions to the ATRAC family, such as ATRAC3plus, ATRAC Advanced Lossless, and ATRAC9 (WAV RIFF). There are other extensions like AT3 out there which use the ATRAC codec, like Sony’s Playstation or PSP. I will have to keep my eyes out for the even more elusive Hi-MD MiniDisc devices to find out more. For now, take a look at some samples and my proposal for signatures on my GitHub.

SDIF

May 17, 2024 by Thor Leave a comment

I have used and have researched a lot of audio editing software. Some are very simple and straightforward, others are feature rich and take some time to learn. While looking in a format, I came across some Audio software which nothing like I have used before. At first I was confused, I figured it would be simple to open a certain file format and play the audio. Not so fast.

Max is software which proudly says it is an, “infinitely flexible space to create your own interactive software”. Created by Cycling ’74 software, Max has been around for awhile, being developed in the mid 1980’s. It allows the user to make “patches” stringing around components and effects to accomplish an infinite amount of options and outcomes.

The software produces simple project files and patch files, but hey are just JSON data, at least in the latest version. But when working with audio files the software can save to a number of formats.

One of the options is a format called “SDIF”, which stands for “Sound Description Interchange Format“. SDIF was jointly developed by IRCAM and CNMAT, with proposals starting back in the mid-1990’s. Originally written as a Spectral Description, it was later changed to refer to a Sound Description.

The Specification states the general idea was to “store information related to signal processing and specifically of sound, in files, according to a common format to all data types. Thus, it is possible to store results or parameters of analyses, syntheses…” So not exactly the same as a simple WAVE file you can open and edit, this format was meant to store signal data for analysis.

Each SDIF file consists of a header and then an overall a succession of frames, not unlike chunks in the IFF/AIFF/RIFF formats, ordered in time. Each frame matrix declares a “Type” which can be a combination of many options. Lets take a look at a SDIF file:

hexdump -C test.sdif | head
00000000  53 44 49 46 00 00 00 08  00 00 00 03 00 00 00 01  |SDIF............|
00000010  31 54 52 43 00 00 00 20  00 00 00 00 00 00 00 00  |1TRC... ........|
00000020  00 00 00 01 00 00 00 01  31 54 52 43 00 00 00 04  |........1TRC....|
00000030  00 00 00 00 00 00 00 04  31 54 52 43 00 00 00 c0  |........1TRC....|
00000040  3f 74 7a e1 40 00 00 00  00 00 00 01 00 00 00 01  |?tz.@...........|
00000050  31 54 52 43 00 00 00 04  00 00 00 0a 00 00 00 04  |1TRC............|
00000060  3f 80 00 00 45 95 35 c3  00 00 00 00 00 00 00 00  |?...E.5.........|
00000070  40 00 00 00 46 06 e2 14  00 00 00 00 00 00 00 00  |@...F...........|
00000080  40 40 00 00 45 3b 42 3d  00 00 00 00 00 00 00 00  |@@..E;B=........|
00000090  40 80 00 00 43 5d 94 7b  00 00 00 00 00 00 00 00  |@...C].{........|

This test file has the opening frame “SDIF“, to identify it as an SDIF, then a reference to the type “1TRC“. I would try and explain a Matrix 1TRC Sinusoidal Track, but I have no idea what it means. Something, something sine wave, etc. Someone much smarter than me can make use of this format. Here are a couple examples of SDIF with other frame types.

hexdump -C angry_cat.part.sdif| head
00000000  53 44 49 46 00 00 00 08  00 00 00 03 00 00 00 01  |SDIF............|
00000010  31 4e 56 54 00 00 00 88  ff ef ff ff ff ff ff ff  |1NVT............|
00000020  ff ff ff fd 00 00 00 01  31 4e 56 54 00 00 03 01  |........1NVT....|
00000030  00 00 00 61 00 00 00 01  53 74 72 65 61 6d 49 44  |...a....StreamID|
00000040  09 30 0a 44 61 74 65 09  54 68 75 5f 41 75 67 5f  |.0.Date.Thu_Aug_|
00000050  5f 33 5f 32 31 2e 33 32  2e 34 35 5f 32 30 30 30  |_3_21.32.45_2000|
00000060  5f 0a 54 61 62 6c 65 4e  61 6d 65 09 53 69 6e 75  |_.TableName.Sinu|
00000070  73 6f 69 64 61 6c 54 72  61 63 6b 73 0a 57 72 69  |soidalTracks.Wri|
00000080  74 74 65 6e 42 79 09 50  6d 5f 56 65 72 73 69 6f  |ttenBy.Pm_Versio|
00000090  6e 5f 31 2e 32 2e 32 0a  00 00 00 00 00 00 00 00  |n_1.2.2.........|

hexdump -C cymbalum-c4.res.sdif| head 
00000000  53 44 49 46 00 00 00 08  00 00 00 03 00 00 00 01  |SDIF............|
00000010  31 52 45 53 00 00 0d 20  00 00 00 00 00 00 00 00  |1RES... ........|
00000020  00 00 00 04 00 00 00 01  31 52 45 53 00 00 00 04  |........1RES....|
00000030  00 00 00 d0 00 00 00 04  42 49 27 7a 39 59 fc ab  |........BI'z9Y..|
00000040  3d 35 06 c9 00 00 00 00  42 6e 68 68 39 63 99 b1  |=5......Bnhh9c..|
00000050  3e 25 f7 c0 00 00 00 00  42 c6 02 bb 39 8c 31 79  |>%......B...9.1y|
00000060  3f bb 7e 6e 00 00 00 00  43 01 82 96 3a 1d 36 44  |?.~n....C...:.6D|
00000070  3e d9 21 12 00 00 00 00  43 07 35 f0 3a 20 6f 6e  |>.!.....C.5.: on|
00000080  3f 02 32 7f 00 00 00 00  43 30 84 0b 39 97 f9 1b  |?.2.....C0..9...|
00000090  3e c6 43 c7 00 00 00 00  43 4d e4 e4 39 88 14 90  |>.C.....CM..9...|

Unfortunately, the common tools I use to explore AV formats don’t seem to work on this format. MediaInfo, FFProbe, Exiftool, all give me unknown file warnings. So I had to compile the SDIF software in order to get some details.

querysdif angry_cat.part.sdif 
Header info of file angry_cat.part.sdif:

Format version: 3
Types version:  1

Ascii chunks of file angry_cat.part.sdif:

1NVT
{
StreamID	0;
Date	Thu_Aug__3_21.32.45_2000_;
TableName	SinusoidalTracks;
WrittenBy	Pm_Version_1.2.2;
}

Data in file angry_cat.part.sdif (9504872 bytes):
 1933 1TRC frames in stream 0 between time 0.000000 and 5.794875 containing
    1933 1TRC matrices with  45 --400 rows,   4 --  4 columns

An interesting thing is that a SDIF file can be in text form as well.

sdiftotext test.sdif 
SDIF


SDFC

1TRC	1	1	0
  1TRC	0x0004	0	4

1TRC	1	1	0.005
  1TRC	0x0004	10	4
	1	4774.72	0	0
	2	8632.52	0	0
	3	2996.14	0	0
	4	221.58	0	0
	5	1943.02	0	0
	6	123.951	0	0
	7	6705.04	0	0
	8	4304.97	0	0
	9	3554.29	0	0
	10	23.7822	0	0

1TRC	1	1	0.01
  1TRC	0x0004	10	4
	1	4774.72	0.0353114	2.06098
	2	8632.52	0.00442518	0.68795
	3	2996.14	0.0238517	-1.42295
	4	221.58	0.0089712	-2.44141
	5	1943.02	0.00768914	2.64629
	6	123.951	0.0397061	-0.17527
	7	6705.04	0.0245643	-0.168753
	8	4304.97	0.00894803	1.45553
	9	3554.29	0.0265175	2.57231
	10	23.7822	0.0419019	-2.17731

1TRC	1	1	0.2
  1TRC	0x0004	10	4
	1	2284.56	0.02781	2.47054
	2	4222.62	0.0151738	1.55309
	3	31.1554	0.00421461	-0.657285
	4	310.99	0.0122306	1.25794
	5	215.192	0.0174093	1.25468
	6	6253.69	0.000894192	2.21334
	7	8533.32	0.0296167	2.07209
	8	8044.77	0.0423002	2.54088
	9	6087.45	0.0264733	-2.05523
	10	7052.7	0.0287347	0.426339

1TRC	1	1	0.205
  1TRC	0x0004	10	4
	1	2284.56	0	0
	2	4222.62	0	0
	3	31.1554	0	0
	4	310.99	0	0
	5	215.192	0	0
	6	6253.69	0	0
	7	8533.32	0	0
	8	8044.77	0	0
	9	6087.45	0	0
	10	7052.7	0	0

1TRC	1	1	0.21
  1TRC	0x0004	0	4

ENDC
ENDF

An interesting format for sure. But wait, there is more!

My initial interest in this format was when I was given access to a set of MUBU files. I was unclear on how there were created at first and it took me down a long path of learning about SDIF and the Max software from Cycling ’74 and IRCAM. MUBU turns out to be a toolbox for Max which adds more analysis features.

MUBU stands for MUlti-BUffer, which helps overcome some limitations. It is actually a container using the SDIF standard. Lets take a look.

hexdump -C test.mubu | head
00000000  53 44 49 46 00 00 00 08  00 00 00 03 00 00 00 01  |SDIF............|
00000010  31 4e 56 54 00 00 00 78  ff ef ff ff ff ff ff ff  |1NVT...x........|
00000020  ff ff ff fd 00 00 00 01  31 4e 56 54 00 00 03 01  |........1NVT....|
00000030  00 00 00 53 00 00 00 01  4d 75 42 75 2e 43 6f 6e  |...S....MuBu.Con|
00000040  74 61 69 6e 65 72 2e 4e  75 6d 54 72 61 63 6b 73  |tainer.NumTracks|
00000050  09 31 0a 4d 75 42 75 2e  43 6f 6e 74 61 69 6e 65  |.1.MuBu.Containe|
00000060  72 2e 56 65 72 73 69 6f  6e 09 31 2e 35 0a 4d 75  |r.Version.1.5.Mu|
00000070  42 75 2e 43 6f 6e 74 61  69 6e 65 72 2e 4e 75 6d  |Bu.Container.Num|
00000080  42 75 66 66 65 72 73 09  31 0a 00 00 00 00 00 00  |Buffers.1.......|
00000090  31 4e 56 54 00 00 00 38  ff ef ff ff ff ff ff ff  |1NVT...8........|

A MUBU file has the same SDIF frame header, but also include a “1NVT” frame, which is a Name Value Table. This is where the MUBU container is referenced. The MuBu file has its own structure:

If I query the MuBu file like I did the SDIF, I get the following:

querysdif test.mubu
Header info of file test.mubu:

Format version: 3
Types version:  1

Ascii chunks of file test.mubu:

1NVT
{
MuBu.Container.NumTracks	1;
MuBu.Container.Version	1.5;
MuBu.Container.NumBuffers	1;
}
1NVT
{
MuBu.Buffer.Index	0;
}
1NVT
{
MuBu.Track.MxRows	2;
AudioFile	1;
MuBu.Track.NonNumType	0;
MuBu.Track.MaxSize	93515;
meta_ISFT	Lavf60.16.100;
MuBu.Track.Name	mytrack;
MuBu.Track.BufferIndex	0;
MuBu.Track.SampleRate	48000;
FileName	Wilhelm_Scream.wav;
MuBu.Track.MxVarRows	0;
MuBu.Track.MxCols	1;
meta_MetaDataSource	WAV;
MuBu.Track.EndTime	1623.5;
FilePath	/;
MuBu.Track.SampleOffset	0;
MuBu.Track.TimeTags	0;
MuBu.Track.Size	77929;
MuBu.Track.Index	0;
}

1TYP
{
  1MTD	M000	{unnamed}
  1FTD	M000
	{
	  M000	Track-0-MatrixData;
	}
}

Data in file test.mubu (3741392 bytes):
77929 M000 frames in stream 0 between time 0.000000 and 1.623500 containing
   77929 M000 matrices with   2 --  2 rows,   1 --  1 columns

The MuBu file contains one audio track and one buffer. This is a simple test file, but MuBu files can be quite large with multiple tracks.

Working with the Max software or OpenMusic is not something I found to be easy to understand. I am sure if I was more musically inclined and with a little practice I could make some of this work. For the time being, a signature to identify a SDIF and MUBU will have to do. Check out the GitHub for my proposed signature and a couple examples.

Sibelius

April 12, 2024 by Thor Leave a comment

Music notation software is among the earliest software for desktop computers. SCORE in 1987, Finale came around in 1988, Capella in 1992, and Sibelius in 1993. Many others came and went during this time. Music notation software was so much more than the typical word processing or desktop publishing system. Specialized fonts were needed to display the music notation and there are many other variables for different instruments allowing individuals and others the ability to create complicated compositions in an inexpensive way.

Sibelius [SI] + [BAY] + [LEE] + [UHS] was originally developed for the Acorn system in 1986, then released on Windows and Macintosh in 1998-99. The software became very popular and in 2006 was purchased by the software giant AVID. The software was used enough to get a preservation assessment by the British Library in 2017 and draft status format description by the Library of Congress, written by the amazing Ashley!

Both reviews of the format emphasize the proprietary nature of the file format which has been used since the early versions. Aside from the early Acorn release, the Windows and Macintosh versions used a binary format with the SIB extension. They are actually quite easy to identify.

hexdump -C Sibelius-s01.sib | head
00000000  0f 53 49 42 45 4c 49 55  53 00 00 40 00 02 00 a4  |.SIBELIUS..@....|
00000010  f1 ed 00 00 00 30 00 00  00 02 00 00 00 01 00 00  |.....0..........|
00000020  00 2a 00 00 00 00 00 00  00 00 0f 53 49 42 45 4c  |.*.........SIBEL|
00000030  49 55 53 00 00 40 00 02  00 00 00 00 00 00 00 3a  |IUS..@.........:|
00000040  00 00 00 00 38 a1 28 06  b3 d2 2f 66 03 04 16 4e  |....8.(.../f...N|
00000050  5f 5c 8d f3 95 27 3e f1  2a 1b 68 de 08 81 e8 9a  |_\...'>.*.h.....|
00000060  ea 1c bf dd 54 0e 92 8d  4d be e3 34 ed 42 78 36  |....T...M..4.Bx6|
00000070  d2 e1 67 7b 8d f7 98 6a  3a 70 c4 8b 0b 08 7b 26  |..g{...j:p....{&|
00000080  f9 45 00 00 00 00 48 71  7c 4c 98 df 0b 38 7d 9d  |.E....Hq|L...8}.|
00000090  2a 2d 84 9c a4 39 0f 4d  da a2 cc 97 ad 3d b0 55  |*-...9.M.....=.U|

This is exactly how PRONOM and other identification methods determine they are Sibelius files. PRONOM has assigned the format fmt/696 and is looking for the hexadecimal bytes 0F534942454C495553.

The problem with this identification method is that all the Sibelius files are identified as such, regardless of version. As mentioned by Ashley, version of the software used is highly important as new features were added all the time making backwards compatibility difficult. Add in the fact that there were different releases for each version which would limit these features even more and I can see how a musician could get very frustrated. If you created a score in Sibelius 5 and tried to open in Sibelius 5 Student version, you may find your composition lacking in many ways. The only way to avoid compatibility issues is to always open in the latest “Ultimate” version. Sibelius Ultimate can open all versions of the SIB format back to version 2. The software even has an export feature which allows you to export back to a previous version stripping what is necessary to ensure compatibility.

For those with a bunch of SIB files in their archives, how would you know which software version created the file? Well lets take a closer look at the bytes and see if we can find some patterns. Let it be known, I am not reverse engineering the format, just looking for patterns which will allow for proper identification!

I am not the first person to ask this question, many others want to know the versions of their SIB files. Thankfully others have found some clues on which bytes hold the version information. It seems we can determine the version based on 4 bytes shortly after the SIBELIUS string. Specifically bytes 10-13.

hexdump -C Sibelius2-s01.sib | head
00000000  0f 53 49 42 45 4c 49 55  53 00 00 08 00 22 00 47  |.SIBELIUS....".G|
00000010  98 4c 00 00 00 3a 00 00  00 00 4e 81 49 34 41 2c  |.L...:....N.I4A,|
00000020  fa 76 62 f9 71 53 a9 93  0f 54 1e 20 6c 63 61 4d  |.vb.qS...T. lcaM|
00000030  f7 b2 b0 a7 5d bd 82 3a  0d 86 02 8b f2 89 d2 a0  |....]..:........|
00000040  83 1f 8d e0 37 1b ed 1c  6a 8b 82 08 4b 6d 64 60  |....7...j...Kmd`|
00000050  71 59 e8 aa ef b1 3c df  5c 25 0a 9f 66 50 69 de  |qY....<.\%..fPi.|
00000060  2a d3 4e 2a cd 97 88 06  67 5f 50 64 0f 8f 86 2b  |*.N*....g_Pd...+|
00000070  08 0d 3f f7 80 26 e0 63  f6 7d 4e f8 e7 c0 3f fc  |..?..&.c.}N...?.|
00000080  7a 77 ea b3 4a b9 30 59  13 47 6e 09 0a 0b ae 3c  |zw..J.0Y.Gn....<|
00000090  c1 93 85 f6 41 f8 58 22  4b 92 35 3f b2 f5 3f 9d  |....A.X"K.5?..?.|

From what others have gathered and updating it with more recent versions I have come up with a list.

Version	Hex 10-13
Sibelius 1.2	00 00 00 0E
Sibelius 2.x	00 08 xx xx
Sibelius 3.x	00 0A xx xx
Sibelius 4.x	00 1B xx xx
Sibelius 5.0	00 2D 00 03
Sibelius 5.1	00 2D 00 0D
Sibelius 5.2.x – 5.4	00 2D 00 10
Sibelius 6.0.x	00 36 00 01
Sibelius 6.1	00 36 00 17
Sibelius 6.2	00 36 00 1E
Sibelius 7.0	00 39 00 0C
Sibelius 7.0.1 – 7.0.2	00 39 00 0E
Sibelius 7.0.3	00 39 00 13
Sibelius 7.1.0	00 39 00 15
Sibelius 7.1.2 – 7.1.3	00 39 00 16
Sibelius 7.5.x	00 3D 00 0E
Sibelius 8.0.0 – 8.0.1	00 3D 00 10
Sibelius 8.1.x	00 3E 00 00
Sibelius 8.2	00 3E 00 01
Sibelius 8.3	00 3E 00 02
Sibelius 8.4.x	00 3E 00 06
Sibelius 8.5.x	00 3E 00 07
Sibelius 8.6.x, 8.7.0, 8.7.1	00 3F 00 00
Sibelius 8.7.2, 2018.1, 2018.4.x, 2018.5, 2018.6, 2018.7	00 3F 00 01
Sibelius 2018.11, 2018.12	00 3F 00 02
Sibelius 2019.1	00 3F 00 04
Sibelius 2019.4.x, 2019.5, 2019.7, 2019.9	00 3F 00 06
Sibelius 2019.12	00 3F 00 07
Sibelius 8.6-2019.12	00 3F 00 0A
Sibelius 2020.1	00 3F 00 0B
Sibelius 2020.3, 2020.6	00 40 00 01
Sibelius 2020.9	00 40 00 02
Sibelius 2022.5	00 40 00 03
Sibelius 2022.11	00 41 00 02
Sibelius 2022.12	00 42 00 00
Sibelius 2023.3	00 42 00 01
Sibelius 2023.8	00 43 00 07
Sibelius 2024.3.1	00 44 00 01

That is a lot of versions and I feel there may be some gaps that still need to be identified. It appears that the first two bytes are the major version and the second set of bytes is the minor version. Although it looks like a few major version bytes span across a few software versions. With this chart, one could be very specific in identifying which Sibelius version wrote the file, but for archiving purposes it seems we can group many of these capturing just the major version. The export screenshot above seems to have broken down significant changes and grouped similar formats together, the biggest being 8.6 through 2019.12. A comparison of “student” and “first” formats don’t have any obvious bytes which indicate as such, so for now they are all lumped together.

There is one other similar format which needs to be mentioned. Sibelius Scorch was a product made to share scores online. This has been replaced with Sibelius Cloud Publishing, but for awhile was the best way to share a score with others in a way that protected the original. I have no idea how they were made, but sites like scorestreet.net and sibeliusmusic.com were sites you could upload your score to for sharing. Some SCO files appear to have a PDF embedded within them for proper printing.

hexdump -C smd_h_0000000000097761.sco | head
00000000  0f 43 43 53 43 4f 52 43  48 00 00 36 00 1e 00 c0  |.CCSCORCH..6....|
00000010  d4 55 00 00 00 30 00 00  00 01 00 00 00 01 00 00  |.U...0..........|
00000020  00 22 0f 43 43 53 43 4f  52 43 48 00 00 36 00 1e  |.".CCSCORCH..6..|
00000030  00 00 00 00 00 00 00 3a  00 00 00 00 03 56 11 b9  |.......:.....V..|
00000040  70 dc fe 90 50 48 30 df  eb 39 88 23 8e 88 78 bf  |p...PH0..9.#..x.|
00000050  da ab ab 5b e2 13 98 89  66 eb 94 67 8d 16 00 00  |...[....f..g....|
00000060  00 00 cf 6f 0c 67 85 ec  57 90 e5 c1 ea 8a eb 9f  |...o.g..W.......|
00000070  c8 13 d2 1d 75 bd a5 9f  eb b9 ef 1d 25 79 45 2c  |....u.......%yE,|
00000080  05 bb 74 41 e8 8f 27 6a  01 07 d0 f5 3b 17 ce 87  |..tA..'j....;...|
00000090  7b c2 82 d9 41 6b 82 2f  d8 b8 17 32 fa d3 59 05  |{...Ak./...2..Y.|

I am not sure the best way to handle all the different versions within the PRONOM registry. I went ahead and made a few signatures based on the export dialog of Sibelius 2024. Even with combining a few together, it leaves us with 17 new PUID’s. Maybe further discussion can refine these down a bit more? Regardless, each file can be associated with a specific Sibelius version, making it easier to open and migrate if needed without fear of opening in the wrong version. Take a look at some samples and my signatures on my GitHub page and let me know if there is a better way.

Shorten

April 5, 2024 by Thor Leave a comment

I was recently going through some of my old CD-R’s and came across this 11 year old fun memory.

I remember going to this 2003 Toad the Wet Sprocket concert in Salt Lake City with some friends, I had seen this band perform before, but this was the first time I was able to get a recording of the show. Normally having a recording of a concert of a well known band was a little shady, but for some bands, they not only allow recording of their live concerts, but they encourage it. There has been a few bands over the years who have this philosophy, one most have heard of is the Grateful Dead, because of all the tape trading, the band’s numerous concerts will live on forever.

The scene of recording concerts is still alive and well, and if you are into recording and sharing it is expected you share in a lossless audio format. The world of lossless audio is definitely in the minority of all those who listen to music on the daily. Most of us have been placated with the infinite playlists on services like Apple Music, Spotify, and Amazon Music. Most probably don’t care about owning music anymore, but for the few who consider themselves Audiophiles, having a lossless audio file is the only choice.

When it comes to formats, there are a few lossless formats to choose from, they all come with some advantages as well as some downsides. WAV files contain the full PCM audio stream, and while internet bandwidth today can handle full uncompressed audio, it can still be beneficial to use some compression for archiving or sharing over the web.

The most common lossless format today is the Free Lossless Audio Codec or FLAC, but there are also quite a few who like the Apple Lossless Audio Codec. Both offer many advantages, especially with metadata, cuesheets, and can contain cover album art. But many years ago another lossless format was most often used with bootleg recordings and audio sharing.

Shorten was one of the first lossless formats, developed by Tony Robinson in 1993 for SoftSound. It could cut the size in half of a typical 16-bit WAV file. It achieved this by using Huffman coding, kinda the same way a JPEG works, by reducing the frequency of how often patterns occur. Today FLAC and ALAC have replaced this format and offer improved features and support. Many audio players have dropped support for shorten making it difficult to use this old format.

The Shorten format uses the .SHN extension. It is one of the formats listed on the Library of Congress Sustainability of Digital Formats with the ID fdd000199, although a couple links don’t appear to work as it hasn’t been updated since 2011. Support was ended for this format and many of the links found on various websites are for broken, usually referencing the etree wiki. Much of which is archived on the Internet Archive.

Let’s take a look at the what makes up a lossless compressed SHN file. A quick look at a sample header:

hexdump -C test.shn | head
00000000  61 6a 6b 67 02 fb b1 70  09 f9 25 59 52 a4 d1 a8  |ajkg...p..%YR...|
00000010  dd cf 85 5a 01 57 a0 d5  a8 b6 6b 6d d2 41 10 80  |...Z.W....km.A..|
00000020  40 20 10 18 04 0a 01 44  d6 40 20 11 0d 8c 0a 01  |@ .....D.@ .....|
00000030  04 80 44 20 16 4b 0d d2  c3 b8 f8 55 a0 11 80 59  |..D .K.....U...Y|
00000040  98 56 1d b1 79 51 9f 39  f1 12 d2 d3 75 5c cd 08  |.V..yQ.9....u\..|
00000050  06 25 68 6b 52 5e 9f 4c  39 cd c1 32 c4 0d a9 b7  |.%hkR^.L9..2....|
00000060  69 34 56 f0 96 fa 46 89  a2 6e 8c ba d5 d0 58 de  |i4V...F..n....X.|
00000070  f5 44 5b aa 61 82 c7 85  88 37 d6 ee cb ab 4e 44  |.D[.a....7....ND|
00000080  91 19 b7 38 d4 20 ae 98  98 d1 2c 4a 4e 88 dd 3e  |...8. ....,JN..>|
00000090  36 68 1b 59 a8 7d 84 23  76 0a 84 21 a1 cd 80 8e  |6h.Y.}.#v..!....|

The first four bytes seem to be consistent among my samples. It makes me wonder if the ascii values have something to do with the author, Anthony (Tony) J. Robinson. In the source code for the shorten software, the file shorten.h defines the ascii “ajkg” as the magic header for the SHN format. Also found in current ffmpeg code. Although the tools don’t have much to say about them.

mediainfo test.shn 
General
Complete name                            : test.shn
Format                                   : Shorten
Format version                           : 2
File size                                : 3.17 MiB

Audio
Format                                   : Shorten
Compression mode                         : Lossless

ffprobe -i test.shn
Input #0, shn, from 'test.shn':
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #0:0: Audio: shorten, 44100 Hz, 2 channels, s16p

Using the older SHNTOOL, we can get more information.

shntool info test.shn  
-------------------------------------------------------------------------------
File name:                    test.shn
Handled by:                   shn format module
Length:                       0:32.23
WAVE format:                  0x0001 (Microsoft PCM)
Channels:                     2
Bits/sample:                  16
Samples/sec:                  44100
Average bytes/sec:            176400
Rate (calculated):            176400
Block align:                  4
Header size:                  44 bytes
Data size:                    5697720 bytes
Chunk size:                   5697756 bytes
Total size (chunk size + 8):  5697764 bytes
Actual file size:             3325489
File is compressed:           yes
Compression ratio:            0.5836
CD-quality properties:
  CD quality:                 yes
  Cut on sector boundary:     no
  Sector misalignment:        1176 bytes
  Long enough to be burned:   yes
WAVE properties:
  Non-canonical header:       no
  Extra RIFF chunks:          no
Possible problems:
  File contains ID3v2 tag:    no
  Data chunk block-aligned:   yes
  Inconsistent header:        no
  File probably truncated:    unknown
  Junk appended to file:      unknown
  Odd data size has pad byte: n/a
Extra shn-specific info:
  Seekable:                   yes

Many Shorten Audio Files are found out there in archives and file sharing sites, so even though the format isn’t used to create new files, it will still be around for awhile. My GitHub has my signature proposal and a couple of samples.

Finale

February 9, 2024 by Thor 4 Comments

The amazing Ashley recently did a little writeup on the Sibelius music notation software. I thought I would take the opportunity to talk about another music notation software which needs a little update. Finale was created in 1987 for the Macintosh by a company called Coda Music and became quite popular with musicians and composers. The ability to use a computer to typeset a musical score was a huge advancement. This was all possible by the use of music notation fonts.

Finale was originally written by Coda Music Technology, owned for a time by Net4Music, now currently owned by MakeMusic. Over the years there has been additional products developed along side Finale.

The first version of Finale was developed for the Macintosh and didn’t have an extension. But by version 3.5 there was a comparable Windows version and the use of the extension .MUS. In order to share the files between the different platforms Finale also created an ETF file, which instead of the binary MUS the ETF is a plain text “transportable” file.

Both formats are based on the Enigma or “Environment for Notation Intuitive Graphic Music Algorithms” format. These formats were last used with Finale 2012 when a new format took over in 2014. Let’s start from the beginning.

hexdump -C Finale1-s01 | head
00000000  46 69 6e 61 6c 65 aa 20  31 2e 30 2e 30 20 45 4e  |Finale. 1.0.0 EN|
00000010  49 47 41 20 53 74 72 75  63 74 75 72 65 73 20 43  |IGA Structures C|
00000020  6f 70 79 72 69 67 68 74  20 31 39 38 37 20 62 79  |opyright 1987 by|
00000030  20 43 6f 64 61 2e 20 41  6c 6c 20 72 69 67 68 74  | Coda. All right|
00000040  73 20 72 65 73 65 72 76  65 64 2e 20 50 61 74 65  |s reserved. Pate|
00000050  6e 74 20 50 65 6e 64 69  6e 67 00 00 00 00 00 00  |nt Pending......|
00000060  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000080  01 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000090  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

This is a sample of the very first version of Finale. Currently not identifiable by PRONOM. You may also noticed in this version it was called ENIGA.

hexdump -C Finale2.6.3 | head
00000000  46 69 6e 61 6c 65 28 54  4d 29 20 31 2e 38 20 43  |Finale(TM) 1.8 C|
00000010  6f 70 79 72 69 67 68 74  20 31 39 38 37 20 62 79  |opyright 1987 by|
00000020  20 43 6f 64 61 2e 20 41  6c 6c 20 72 69 67 68 74  | Coda. All right|
00000030  73 20 72 65 73 65 72 76  65 64 2e 00 00 00 00 00  |s reserved......|
00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000080  01 01 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000090  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000200  00 00 00 09 00 00 02 00  00 00 46 4e 50 65 74 72  |..........FNPetr|

A file from version 2.6.3 shows a different format structure, also not currently identified by PRONOM.

hexdump -C F35-s01.mus | head
00000000  45 4e 49 47 4d 41 20 42  49 4e 41 52 59 20 46 49  |ENIGMA BINARY FI|
00000010  4c 45 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |LE..............|
00000020  46 69 6e 61 6c 65 28 52  29 20 33 2e 35 20 43 6f  |Finale(R) 3.5 Co|
00000030  70 79 72 69 67 68 74 20  28 63 29 20 31 39 39 35  |pyright (c) 1995|
00000040  20 43 6f 64 61 20 4d 75  73 69 63 20 54 65 63 68  | Coda Music Tech|
00000050  6e 6f 6c 6f 67 79 00 00  00 00 00 00 00 00 00 00  |nology..........|
00000060  00 02 00 00 00 00 7c 02  08 00 00 00 03 03 50 03  |......|.......P.|
00000070  46 49 4e 00 57 49 4e 00  02 04 50 03 03 03 50 03  |FIN.WIN...P...P.|
00000080  00 00 00 00 00 00 00 00  00 00 00 00 7c 02 08 00  |............|...|
00000090  00 00 03 03 50 03 46 49  4e 00 57 49 4e 00 02 04  |....P.FIN.WIN...|

By Version 3 we see the format stabilize and this header is used until Finale 2012. There was other various products which also used the format so there is some variation.

hexdump -C Tutorial1a.mus | head
00000000  45 4e 49 47 4d 41 20 42  49 4e 41 52 59 20 46 49  |ENIGMA BINARY FI|
00000010  4c 45 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |LE..............|
00000020  50 72 69 6e 74 4d 75 73  69 63 28 52 29 20 32 30  |PrintMusic(R) 20|
00000030  31 30 20 43 6f 70 79 72  69 67 68 74 20 31 39 39  |10 Copyright 199|
00000040  38 2d 32 30 30 39 20 4d  61 6b 65 4d 75 73 69 63  |8-2009 MakeMusic|
00000050  20 49 6e 63 2e 00 00 00  00 00 00 00 00 00 00 00  | Inc............|
00000060  00 02 0e 01 00 00 6a 02  0e 00 00 00 04 02 02 0b  |......j.........|
00000070  46 49 4e 00 57 49 4e 00  03 04 02 0b 0d 02 00 0b  |FIN.WIN.........|
00000080  00 00 00 00 00 00 00 00  00 00 00 00 6d 08 0d 00  |............m...|
00000090  00 00 31 02 00 0f 4e 54  52 00 4d 41 43 00 10 02  |..1...NTR.MAC...|

The current PRONOM identification for fmt/397 is looking for the “ENIGMA BINARY FILE” bytes but also the string “Finale(R)”, so this PrintMusic variation is not identified correctly.

Another format that is a little more rare to see, but is part of the Finale formats collection. Finale Performance Assessment File (.fpa) is an older format discontinued in 2007, but has a similar format. It was a tool similar to the current SmartMusic tool.

hexdump -C Tuba.FPA | head
00000000  46 49 4e 41 4c 45 20 50  45 52 46 4f 52 4d 41 4e  |FINALE PERFORMAN|
00000010  43 45 20 41 53 53 45 53  53 4d 45 4e 54 00 00 00  |CE ASSESSMENT...|
00000020  46 69 6e 61 6c 65 28 52  29 20 32 30 30 35 20 43  |Finale(R) 2005 C|
00000030  6f 70 79 72 69 67 68 74  20 28 63 29 20 31 39 38  |opyright (c) 198|
00000040  37 2d 32 30 30 34 20 4d  61 6b 65 4d 75 73 69 63  |7-2004 MakeMusic|
00000050  21 20 49 6e 63 2e 00 6f  6c 6f 67 79 00 00 00 00  |! Inc..ology....|
00000060  00 02 06 00 00 00 68 06  09 00 00 00 16 02 00 09  |......h.........|
00000070  46 49 4e 00 57 49 4e 00  01 04 01 09 16 02 00 09  |FIN.WIN.........|
00000080  00 00 00 00 00 00 00 00  00 00 00 00 68 07 0d 00  |............h...|
00000090  00 00 0a 01 00 0a 46 49  4e 00 57 49 4e 00 03 03  |......FIN.WIN...|

As for the Enigma Transportable File, there is a couple variations.

hexdump -C Finale1-s02.etf | head
00000000  45 4e 49 47 4d 41 20 74  72 61 6e 73 70 6f 72 74  |ENIGMA transport|
00000010  61 62 6c 65 20 66 69 6c  65 0d 45 4e 49 47 4d 41  |able file.ENIGMA|
00000020  20 53 74 72 75 63 74 75  72 65 73 20 43 6f 70 79  | Structures Copy|
00000030  72 69 67 68 74 20 31 39  38 37 20 62 79 20 43 6f  |right 1987 by Co|
00000040  64 61 2e 20 41 6c 6c 20  52 69 67 68 74 73 20 52  |da. All Rights R|
00000050  65 73 65 72 76 65 64 2e  20 50 61 74 65 6e 74 20  |eserved. Patent |
00000060  50 65 6e 64 69 6e 67 2e  0d 0d 5e 6f 74 68 65 72  |Pending...^other|
00000070  73 0d 5e 46 4e 28 30 29  20 22 50 65 74 72 75 63  |s.^FN(0) "Petruc|
00000080  63 69 22 0d 5e 49 55 28  30 29 20 31 20 30 20 2d  |ci".^IU(0) 1 0 -|
00000090  38 30 20 32 20 30 20 2d  33 31 36 20 0d 5e 49 55  |80 2 0 -316 .^IU|

hexdump -C Finale37-Sample.etf | head
00000000  45 4e 49 47 4d 41 20 54  52 41 4e 53 50 4f 52 54  |ENIGMA TRANSPORT|
00000010  41 42 4c 45 20 46 49 4c  45 0d 0d 5e 68 65 61 64  |ABLE FILE..^head|
00000020  65 72 0d 5e 30 31 20 22  46 69 6e 61 6c 65 28 52  |er.^01 "Finale(R|
00000030  29 20 33 2e 37 20 43 6f  70 79 72 69 67 68 74 20  |) 3.7 Copyright |
00000040  28 63 29 20 31 39 38 37  2d 31 39 39 36 20 43 6f  |(c) 1987-1996 Co|
00000050  64 61 20 4d 75 73 69 63  20 54 65 63 68 6e 6f 6c  |da Music Technol|
00000060  6f 67 79 22 0d 5e 30 32  20 31 20 30 20 30 20 30  |ogy".^02 1 0 0 0|
00000070  20 0d 5e 30 33 20 31 32  30 20 31 31 20 39 20 0d  | .^03 120 11 9 .|
00000080  5e 30 34 20 22 22 0d 5e  30 35 20 35 37 36 37 32  |^04 "".^05 57672|
00000090  32 30 34 20 0d 5e 30 36  20 22 46 49 4e 22 0d 5e  |204 .^06 "FIN".^|

The current signature of ETF files is only able to correctly identify the later version of the string in all caps. The fmt/398 PRONOM ID could use an alternate signature to ensure all variations are identified correctly. There is a couple versions of the specification out there, but does not add much to what is known.

Starting in 2014 Finale starting using a new file format to store its notations. The native format now uses the MUSX extension. This new format uses a ZIP container to store all the data. Let’s take a look at the inside.

Path = Finale26-s01.musx
Type = zip
Physical Size = 98608

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2022-12-19 16:28:36 .....           34           34  mimetype
2022-12-19 16:28:36 .....          252          168  META-INF/container.xml
2022-12-19 16:28:36 .....          347          218  NotationMetadata.xml
2022-12-19 16:28:36 .....         1163          821  presets/10001.preset
2022-12-19 16:28:36 .....          649          544  presets/1.preset
2022-12-19 16:28:36 .....        96140        96155  score.dat
------------------- ----- ------------ ------------  ------------------------
2022-12-19 16:28:36              98585        97940  6 files

The mimetype file appears to be “application/vnd.makemusic.notation”

The NotationMetadata.xml file stores much of the information needed and begins with the root tag.

<metadata version="26.2" xmlns="http://www.makemusic.com/2012/NotationMetadata">

It seems the presence of the NotationMetadata.xml file and the mimetype would be sufficient for identification in a container signature.

The current version of Finale can export to a few different “Music XML” versions. This includes MUSICXML, regular XML, and a compressed MXL file. The only one needs attention is the compressed MXL file and added to PRONOM. It already has a PUID, fmt/897, but no signature. Here is what it looks like inside the ZIP container.

Path = Finale27-s01.mxl
Type = zip
Physical Size = 4737

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2024-02-07 23:55:50 .....           34           34  mimetype
2024-02-07 23:55:50 D....            0            2  META-INF
2024-02-07 23:55:50 .....          202          144  META-INF/container.xml
2024-02-07 23:55:50 .....        18004         1996  Finale27-s01.musicxml
2024-02-07 23:55:52 .....        17554         1953  p1.musicxml
------------------- ----- ------------ ------------  ------------------------
2024-02-07 23:55:52              35794         4129  4 files, 1 folders

Looks like a standard identifiable MUSICXML file within the container with a mimetype of “application/vnd.recordare.musicxml”. The MUSICXML file will be impossible to use for identification because of the variable file name, but the mimetype should do just fine.

Hopefully that covers all the major formats that need identification. I saw on a list that I will soon be working on an old Macintosh which has hundreds of Finale files, I hope these updates cover those needs! Take a look at my GitHub for my signatures and plenty of samples.

FlashPix

January 19, 2024 by Thor Leave a comment

Is there a perfect raster image format? TIFF has been around quite some time and is generally accepted as a preferred preservation format. There have been a few attempts to have a single file contain multiple resolutions with the purpose of providing resolutions for different uses, lower-resolution for web and higher-resolution for print. Even the semi popular JPEG2000 added multiple resolutions to improve the JPEG format. Kodak came up with a few ideas to do this as well. The Kodak PCD, PhotoCD or Image PAC files was one that was used for awhile before it was abandoned. Another was FlashPix.

I briefly mentioned FlashPix on an earlier post about the Microsoft Picture It! format. They are extremely similar. Both. have the same basic structure in a Compound Object format. Some of the FlashPix files generated by Picture It! even have the same identifiers in the CompObj header.

FlashPix was supposed to be the answer to all the problems with storing bitmap image data and how we view the web. Kodak partnered with some big names, Microsoft Corporation, Hewlett-Packard Company and Live Picture, Inc, were among them. Kodak marketed the format and even included it as a native file format to some of its new digital cameras. The format was made official in June of 1996, with a Whitepaper explaining all the benefits and architecture. There was a lot of hype, some even calling it, “Not your Grandma’s format“. Many graphics software started to include support for the new format, including Adobe Photoshop. So what happened, why didn’t the format catch on? Some say it was the size of storing multiple resolutions in one file, others believe it was the complicated Compound Object structure that lead to its demise. Either way, the format had a lot of hype in the late 1990’s, but by the year 2000, it had gone silent and all the websites went away.

FlashPix did have a big impact, and there were many software and hardware devices which were made compatible. There are a few stories left behind of those who scanned all their photos to the FlashPix format only to find a few years later it was unsupported on more modern computers. There was also a few early digital camera’s which could capture directly to the format. Take my Kodak DC260 zoom camera, circa 1998. Changing the Capture Preferences, I can switch between a JPG and FPX.

Using exiftool we can take a look at one of the images from the camera:

exiftool P0004795.FPX
ExifTool Version Number         : 12.73
File Name                       : P0004795.FPX
Directory                       : GitHub/digicam_corpus/Kodak/DC260/DC260_01
File Size                       : 251 kB
File Modification Date/Time     : 2024:01:06 12:54:20-07:00
File Access Date/Time           : 2024:01:06 13:20:46-07:00
File Inode Change Date/Time     : 2024:01:06 13:04:34-07:00
File Permissions                : -rwxrwxrwx
File Type                       : FPX
File Type Extension             : fpx
MIME Type                       : image/vnd.fpx
Code Page                       : Unicode UTF-16, little endian
Data Object ID                  : 13BC5A58-6B90-1B6B-12C9-0800201177F8
Data Object Status              : Exists, Not Purgeable
Creating Transform              : Source Image
Using Transforms                : 
Cached Image Height             : 1024
Cached Image Width              : 1536
Comp Obj User Type Len          : 16
Comp Obj User Type              : FlashPix_Object
Visible Outputs                 : 1
Maximum Image Index             : 1
Maximum Transform Index         : 0
Maximum Operation Index         : 0
Thumbnail Clip                  : (Binary data 18480 bytes, use -b option to extract)
Revision Number                 : 1
Create Date                     : 2024:01:06 12:53:29
Modify Date                     : 2024:01:06 12:53:29
Software                        : KODAK DIGITAL SCIENCE DC260
Image Width                     : 1536
Image Height                    : 1024
Subimage Width                  : 1536
Subimage Height                 : 1024
Subimage Color                  : RGB
Subimage Numerical Format       : 8-bit, Unsigned
Decimation Method               : None (Full-sized Image)
JPEG Tables                     : (Binary data 558 bytes, use -b option to extract)
Number Of Resolutions           : 1
Max JPEG Table Index            : 1
Scene Type                      : Original Scene
Software Release                : KODAK DIGITAL SCIENCE DC260
Make                            : Eastman Kodak Company
Camera Model Name               : KODAK DIGITAL SCIENCE DC260
Serial Number                   : 7577
Exposure Time                   : 1/180
F Number                        : 4.7
Exposure Program                : Program AE
Exposure Compensation           : 0
Subject Distance                : 0.520 m
Metering Mode                   : Center-weighted average
Light Source                    : Unknown
Focal Length                    : 24.0 mm
Max Aperture Value              : 4.6
Flash                           : No Flash
Exposure Index                  : 90
Sharpness Approximation         : 0
File Source                     : Digital Camera
Sensing Method                  : One-chip color area
Extension Create Date           : 2024:01:06 12:53:29
Extension Modify Date           : 2024:01:06 12:53:29
Creating Application            : Picoss
Extension Name                  : ijuhsimasa
Extension Persistence           : Always Valid
Extension Description           : Data Object Store 000001
Storage-Stream Pathname         : /Data Object Store 000001
Extension Class ID              : 56616000-C154-11CE-8553-00AA00A1F95B
Used Extension Numbers          : 1
Screen Nail                     : (Binary data 4304 bytes, use -b option to extract)
Subimage Tile Count             : 384
Subimage Tile Width             : 64
Subimage Tile Height            : 64
Num Channels                    : 3
Audio Stream                    : (Binary data 30780 bytes, use -b option to extract)
Aperture                        : 4.7
Image Size                      : 1536x1024
Megapixels                      : 1.6
Shutter Speed                   : 1/180
Preview Image                   : (Binary data 4164 bytes, use -b option to extract)
Focal Length                    : 24.0 mm

The file also does identify in PRONOM:

sf P0004795.FPX 
---
siegfried   : 1.11.0
scandate    : 2024-01-17T23:13:59-07:00
signature   : default.sig
created     : 2023-12-17T15:54:41+01:00
identifiers : 
  - name    : 'pronom'
    details : 'DROID_SignatureFile_V116.xml; container-signature-20231127.xml'
---
filename : 'P0004795.FPX'
filesize : 250880
modified : 2024-01-06T12:54:20-07:00
errors   : 
matches  :
  - ns      : 'pronom'
    id      : 'x-fmt/56'
    format  : 'Kodak FlashPix Image'
    version : 
    mime    : 'image/vnd.fpx'
    class   : 'Image (Raster)'
    basis   : 'extension match fpx; container name CompObj with byte match at 53, 36 (signature 2/2)'
    warning :

If you notice, PRONOM has two signatures for the FlashPix format, this image was identified with signature #2. The first signature looks for the string “FlashPix Object”, but the second looks for the CLSID which is unique to each compound object format. FlashPix has the CLSID: {56616700-c154-11ce-8553-00aa00a1f95b}. Looking at many of the other samples I have there is much variation on the use of the string and CLSID.

FlashPix samples:
FlashPix Object({56616000-C154-11CE-8553-00AA00A1F95B}
FlashPix Object({56616800-C154-11CE-8553-00AA00A1F95B}
Picture It! FlashPix'{56616700-C154-11CE-8553-00AA00A1F95B}
LPI FlashPix'{56616700-c154-11ce-8553-00aa00a1f95b}
FlashPix_Object'{56616700-C154-11CE-8553-00AA00A1F95B}
'{56616700-C154-11CE-8553-00AA00A1F95B}
Picture It!'{56616700-c154-11ce-8553-00aa00a1f95b}
Flashpix Toolkit Application'{56616700-c154-11ce-0000-000000000000}

The images from the Kodak Camera use “FlashPix_Object” string so with the underscore it doesn’t match the first signature, but others I made using Picture It! software used a couple variations. Many don’t use the string at all. Others use a sightly different CLSID in both uppercase and lowercase. We will have to suggest adjustments to the current signature to identify them all.

Looking at the contents of the OLE container we can see some interesting things.

Path = P0004795.FPX
Type = Compound
Physical Size = 250880
Extension = compound
Cluster Size = 512
Sector Size = 64

Size         Compressed     Name
------------ ------------  ------------------------
188          192           [5]Data Object 000001
272          320           [1]CompObj
388          448           [5]Extension List
144          192           [5]Global Info
                           Data Object Store 000001
18704        18944         [5]SummaryInformation
816          832           Data Object Store 000001/[5]Image Contents
272          320           Data Object Store 000001/[1]CompObj
988          1024          Data Object Store 000001/[5]Extension List
1624         1664          Data Object Store 000001/[5]Image Info
4332         4608          Data Object Store 000001/[5]Screen Nail_bd0100609719a180
                           Data Object Store 000001/Resolution 0005
                           Data Object Store 000001/Audio_bd0100609719a180
1112         1152          Data Object Store 000001/[5]KDC_bd0100609719a180
72           128           Data Object Store 000001/[5]SummaryInformation
108          128           Data Object Store 000001/Audio_bd0100609719a180/[5]Audio Info
30808        31232         Data Object Store 000001/Audio_bd0100609719a180/Audio Stream 000000
6208         6656          Data Object Store 000001/Resolution 0005/Subimage 0000 Header
176378       176640        Data Object Store 000001/Resolution 0005/Subimage 0000 Data
------------ ------------  ------------------------
242414       244480        16 files, 3 folders

The main CompObj is where we find the identification information, but the Data Object Store 000001 directory is where all the image data is stored. In a multiple resolution image we might see additional Resolution directories. You may also notice a mention of an Audio directory. Yes, this image was captured and then audio was recorded with it. Not a video, but an audio clip associated with the image. FlashPix can contain audio streams. This isn’t the first time we have seen this, HP camera’s also have this function which as it turns out is stored in a FlashPix exif extension within a JPEG.

The FlashPix native format may have disappeared, but the format lives on as an extension to Exif data, allowing you to embed audio and other media within a JPEG file. The code for FlashPix was given to ImageMagick and is maintained by them.

RCA-VOC

November 24, 2023 by Thor Leave a comment

I wonder sometimes what goes through a software/hardware developers mind when deciding a format to use for a new device. There are so many options our there for audio formats to choose from. I am sure there are pros and cons to using one technology over another but it seems a few decide to go ahead and make their own. I am sure there is some commercial advantage to developing a proprietary audio format, but with all the established choices it seems unnecessary.

Sony developed their own audio compression formats, which I explored in an earlier blog post. I came across a small goofy looking RCA voice recorder, model VR6320.

Many of these RCA VR series recorders can record in a WAV or a VOC file format. The WAV files are pretty run of the mill, but the VOC format is unique to RCA recorders.

The VOC format is not to be confused with another audio format with the same extension. The Creative Voice Format is a bit more well known. It was used with the Creative’s sound cards (Sound Blaster family) many folks had in their Windows computers in the 1990’s. But the RCA file format is different, and because of the same extension needs its own identification so they are not confused with each other.

sf REC00001.VOC 
---
siegfried   : 1.10.1
scandate    : 2023-11-19T23:33:47-07:00
signature   : default.sig
created     : 2023-05-12T09:10:13Z
identifiers : 
  - name    : 'pronom'
    details : 'DROID_SignatureFile_V112.xml; container-signature-20230510.xml'
---
filename : 'REC00001.VOC'
filesize : 47231
modified : 2015-01-09T20:51:10-07:00
errors   : 
matches  :
  - ns      : 'pronom'
    id      : 'UNKNOWN'
    format  : 
    version : 
    mime    : 
    class   : 
    basis   : 
    warning : 'no match; possibilities based on extension are fmt/1736'

The RCA VOC file format seems to be undocumented, there isn’t much available. You can always download a copy of the RCA Digital Voice Manager software, which may or may not run on your current system, and convert the VOC files to WAV or you can use a piece of software coded in 2008 called “devoc“. The developer used to have an online website you could upload the VOC to and it would convert it automatically, but is not longer available. The code can also be found here.

Let’s take a look at the header of a couple of the files I have:

hexdump -C REC00001.VOC | head
00000000  56 43 50 31 36 32 5f 56  4f 43 5f 46 69 6c 65 0c  |VCP162_VOC_File.|
00000010  0f 01 09 14 32 1c 00 00  0b 44 03 00 00 00 00 00  |....2....D......|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000001b0  00 10 00 00 00 00 00 00  00 00 00 10 00 00 00 00  |................|
000001c0  00 00 00 00 00 10 00 00  00 00 00 00 00 00 00 10  |................|
000001d0  00 00 00 00 00 00 00 ff  ff ff ff ff ff ff ff ff  |................|
000001e0  ef 11 14 d3 96 77 57 44  34 33 34 44 43 33 44 43  |.....wWD434DC3DC|
000001f0  43 34 44 34 43 43 34 44  43 43 33 35 43 33 43 34  |C4D4CC4DCC35C3C4|
00000200  34 43 43 24 34 43 43 33  44 51 33 42 14 44 32 43  |4CC$4CC3DQ3B.D2C|

hexdump -C A0000003.VOC | head
00000000  52 50 35 31 32 30 5f 56  4f 43 5f 46 69 6c 65 78  |RP5120_VOC_Filex|
00000010  08 06 16 0a 0f 20 00 04  17 01 03 00 00 00 00 00  |..... ..........|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000180  00 03 b9 2f 00 07 62 af  00 0b 0c 2f 00 0e b5 af  |.../..b..../....|
00000190  00 12 5f 2f 00 00 00 00  00 00 00 00 00 00 00 00  |.._/............|
000001a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000fa0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 e1  |................|
00000fb0  ea eb ea fe df ae 4e a1  1d cd 1c cf 9f de cf 3b  |......N........;|

Most of samples I have show “VCP162_VOC_File” in the header, but I have one sample with “RP5120_VOC_File“. I have heard of others, one being “V432_Voice_File“. There could be more variations. One could assume the header is somehow associated with the model number of the device, but that doesn’t appear to be the case. Although there is a device with the model number “RP 5120“. It might be that the older RP series get one header and the newer VR Series get VCP? I will need more samples to confirm, if you have any send them my way. Also, according to the manuals, there is a SP and LP mode to manage the bitrate of the file to squeeze more minutes on the built in memory of these devices. This doesn’t appear to affect identification, but might be good to differentiate in the future.

For now you can take a look at the signature on my GitHub page.

HighMAT

September 8, 2023 by Thor Leave a comment

Before the days of streaming and devices likeSmart TVs, AppleTV and Fire sticks, a few companies tried their best to come up with ways to make viewing your media on your TV mainstream. In a previous blog post I touched on the Kodak PhotoCD method, but there is one you are probably even less familiar with. HighMAT. HighMAT, or High-Performance Media Access Technology was a technology co-developed by Microsoft and Panasonic. You may have at one point owned a DVD player which had the technology built-in, but may have never used it. It came on the scene around 2002, but was abandoned by 2008.

Panasonic DVD/CD Player with HighMAT playback.

There were quite a few devices stamped with the HighMAT logo. The technology allow you to playback any Audio and Images like a DVD, with a menu and everything.

There was three different types of HighMAT compatible devices, Audio, Audio-Image, and Audio-Image-Video.

Writing data to the HighMAT format could be done with a plugin for Windows which added the functionality to Windows Media Player for burning audio playlists to the HighMAT format or through the standard CD Writing Wizard built-in to Windows XP. An extra screen would come up asking if you would like to make the CD HighMAT compatible. Making video compatible HighMAT CDs could be done through Movie Maker.

When a HighMAT CD-R/CD-RW is authored we get an interesting CD. It appears to be a Mode 2 Form 1 format:

/dev/disk10 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:        CD_partition_scheme                        *846.4 MB   disk10
   1:       CD_ROM_Mode_2_Form_1 Highmat02               2.7 MB     disk10s0

If you would like to check out a sample disc, you can grab the ISO or BIN/CUE here.

tree /Volumes/Highmat02
/Volumes/Highmat02
├── Audio\ Samples
│   ├── 17\ [no\ artist]\ -\ Speaker\ Identification\ Test.wma
│   └── sine.wma
├── HIGHMAT
│   ├── AUTHOR.XML
│   ├── CONTENTS.HMT
│   ├── IMAGES
│   │   ├── T0.HMT
│   │   ├── T1.HMT
│   │   ├── T10.HMT
│   │   ├── T11.HMT
│   │   ├── T12.HMT
│   │   ├── T13.HMT
│   │   ├── T2.HMT
│   │   ├── T3.HMT
│   │   ├── T4.HMT
│   │   ├── T5.HMT
│   │   ├── T6.HMT
│   │   ├── T7.HMT
│   │   ├── T8.HMT
│   │   └── T9.HMT
│   ├── MENU.HMT
│   ├── PLAYLIST
│   │   ├── 00000001.HMT
│   │   ├── 00000002.HMT
│   │   ├── 00000003.HMT
│   │   ├── 00000004.HMT
│   │   ├── 00000005.HMT
│   │   ├── 00000006.HMT
│   │   └── 00000007.HMT
│   └── TEXT.HMT
└── My\ Pics
    ├── Blue\ hills.jpg
    ├── Sunset.jpg
    ├── Water\ lilies.jpg
    └── Winter.jpg

5 directories, 31 files

There is a lot going on here, lets take a look at a few of the formats we find in this disc structure. The files added to the CD are converted to WMA if you checked the “Convert Files” feature and are accessible like a normal data CD. The HighMAT folder is created to make a compatible HighMAT disc. Except for one XML file the rest of the files in the HighMAT folder all have an HMT extension. The author.xml file contains the root element <HMT> with some filenames indicating some of the HMT files may be thumbnails. If we open one of the HMT thumbnail files in a hex editor we can see:

Just a plain old JPG header. Exiftool tells us it is small 160×120 pixel image, must be a thumbnail. But lets take a look at another HMT file.

Even though the Menu.hmt file has the same extension as the thumbnails, this file is definitely not a JPG file with pixel data. Same goes for the Contents and Text files as well, unique formats.

The files in the playlist folder also have a unique format.

So it seems all the HighMAT folder really does is add compatibility for hardware to provide a menu to access the original data, providing playlists and thumbnails to navigate the data on your TV screen.

I came across one of these discs while processing a collection of CD-R discs donated to our library. Normally I would copy the images and other data off the disc to our preservation system, but this disc made me stop to think about the best way to preserve the data. Is a disc image appropriate or is the HighMAT folder even worth preserving if we have the original files from the disc? Finding hardware or a software player to present the disc as intended is getting harder to do. I am curious what others think of the value of this content.

I chose not to submit any signatures to PRONOM for the moment as we assess. It would be difficult to properly identify each format with all of them having the same extension, especially the JPG thumbnails as HMT is not a valid extension for the format. Take a look at my sample files and if you have come across this format before, let me know.

Shockwave Audio

August 4, 2023 by Thor Leave a comment

Ok, confession time.

There is only a couple moments in my tech history which had a profound effect on me, enough to sear the memory of the moment into my brain. When I was in college around 1997 I had a decent CD collection and I had learned how to copy those AIFF files off the disc and use them on my trusty PowerCenter Pro. These files were huge, at the time. I knew a regular size song would take up around 50MB on my hard drive. This was a lot of space back in 1997, but I could then mix them with other songs, something I did sometimes for friends I had on the dance team. I didn’t have a CD burner at the time so I would transfer them to cassette tape. I know, but remember this was the 1990’s when everything was changing and expensive.

One night I was exploring the world wide web and I happened across someone sharing a few songs. I assumed they were just clips as they were only 5MB in size, a tenth the size they should be. I downloaded the song, which of course still took a few minutes back in those days. When I played the song, I was dumbfounded, it was the whole song. I was completely confused. How could they take a 4+ minute song and compress it down to under 5MB? This was amazing.

I started grabbing every song I could find. Before long I had quite the collection. And before you judge me for downloading music from the web, this was a couple years before the advertisement we all remember reminding us that we wouldn’t steal a car so why would we steal music.

The files I found on the internet were MP3 files, the same we are familiar with today. Back then creating MP3 files wasn’t easy. MP3 was actually a licensed product so you had to get a little creative in order to make them. On my Macintosh PowerCenter Pro, there were even fewer options. I was already familiar with the sound editing application from Macromedia called SoundEdit 16, it was the tool I used to do all my editing. I found there was a plugin you could add which allowed export to a format called Shockwave Audio. This was meant for use in Macromedia’s Director application to add sound to the growing Flash animation industry. Once I got the plugin and installed I couldn’t stop making files and I made them as fast as I could. For a whole album this could take over an hour on my hardware, but it was worth it. Before long I had a large collection of popular music ready to play at a moments notice. My player of choice was MacAMP, a sibling of the popular WinAMP. I even borrowed some equipment from a friend who DJ’d on the weekends and DJ’d a college dance. I lugged my whole PowerCenter Pro tower and 17in trinitron monitor over to the school. It was so much fun and folks didn’t understand when they asked to see my CD collection.

Enough about transgressions from my youth, lets talk about the Shockwave Audio format.

To create a SWA file you would first need SoundEdit 16 Version 2. Then the plugins to enable export. This would only run on PowerPC computers running Macintosh OS or Classic in Mac OS X. For this post I pulled out my trusty PowerBook G4 Titanium running MacOS 9 and MacOS X 10.2. Installed SoundEdit 16 and the plugins in the Xtras folder and we are good to go.

Before you export you need to set what bitrate you prefer for the final file, giving you the option of 8KBits up to 160KBits per second. The higher the bitrate the longer it took and made larger files.

SoundEdit 16 had a native audio format and also frequently used the SoundDesigner II format to save the uncompressed files. On a Macintosh you had to be careful as these formats did not travel well to other systems on account of the resource forks associated with the data.

Because these SWA files were meant to be used in websites and other non-Mac systems, they did not have a resource fork, but had the Creator/Type codes, SwaT/SHCK. An extension wasn’t necessary for use on your Macintosh, but it was best to use .swa.

Here is what the data looks like for a SWA file.

Even though the SWA format uses MPEG compression, this is not a typical header you might see in a MP3. There was no ID3 tags at the time so not much in terms of metadata.

General
Complete name                            : tone2.swa
Format                                   : MPEG Audio
File size                                : 80.7 KiB
Duration                                 : 5 s 166 ms
Overall bit rate mode                    : Constant
Overall bit rate                         : 128 kb/s
FileExtension_Invalid                    : m1a mpa mpa1 mp1 m2a mpa2 mp2 mp3

Audio
Format                                   : MPEG Audio
Format version                           : Version 1
Format profile                           : Layer 3
Format settings                          : Joint stereo / MS Stereo
Duration                                 : 5 s 172 ms
Bit rate mode                            : Constant
Bit rate                                 : 128 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 44.1 kHz
Frame rate                               : 38.281 FPS (1152 SPF)
Compression mode                         : Lossy
Stream size                              : 80.7 KiB (100%)

ffprobe -i tone2.swa 
[mp3 @ 0x155704a60] Format mp3 detected only with low score of 25, misdetection possible!
[mp3 @ 0x155704a60] Skipping 324 bytes of junk at 0.
[mp3 @ 0x155704a60] Estimating duration from bitrate, this may be inaccurate
Input #0, mp3, from 'tone2.swa':
  Duration: 00:00:05.15, start: 0.000000, bitrate: 128 kb/s
  Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s

There are a few consistencies among all my files. They all begin with the hex values “00000140000000030000” for the first 10 bytes and all of them seem to have the string “MACRZ” at offset 36. I haven’t been able to find a open specification for this file format, so we will have to go with what we can find in the samples. According to ffprobe from above, there is 324 bytes of a header before the first MP3 frame starts.

MPEG signatures are difficult, there are no headers, just a sequence of frames. This is why there are often so many identification conflicts with the MP3 format. These SWA files indeed identify as MP3 files, but with a mismatch extension.

filename : 'tone2.swa'
filesize : 82661
modified : 1970-01-01T00:00:00-07:00
errors   : 
matches  :
  - ns      : 'pronom'
    id      : 'fmt/134'
    format  : 'MPEG 1/2 Audio Layer 3'
    version : 
    mime    : 'audio/mpeg'
    class   : 'Audio'
    basis   : 'byte match at 0, 4088 (signature 5/9)'
    warning : 'extension mismatch'

If we wanted to distinguish an SWA from an MP3 we would need to create a new signature and give it priority over the MP3 signature. There is enough of a header this would be possible and easier, but since they are, in reality, just MP3 files does it matter? Trying to play a SWA on a modern computer is only possible if you change the extension to MP3.

If you want to take a look at some samples you can grab a couple I made on my GitHub page or check out some commercially made files for an awesome Star Trek Starship Creator game.