AskSam

January 26, 2024 by Thor Leave a comment

I was recently asked to look at a set of files with the extension of .ASK. A quick little search led me to find they belong to AskSam which was a free-form database software often used by researchers and libraries as early as 1985. The first few versions of Access Stored Knowledge via Symbolic Access Method were released for DOS and later Windows. The company askSam Systems disappeared around 2015.

The AskSam software competed with other personal information managers with unstructured data storage and retrieval. It was used to keep track of e-mail, special collections, letters, articles, web sites, etc. It could index all the contents and make searching and retrieval easy. By setting up fields the data could be exported to delimitated text. The software also appears to have been localized in German, but file format is the same.

AskSam had many import filters which included:

Microsoft Word
WordPerfect
Text (ASCII files)
HTML Files (from the Internet)
RTF Files (Rich Text Format)
Eudora E-Mail
Microsoft Outlook
Microsoft Outlook Express
Text delimited files – Comma Separated Values, Fixed position, etc.
dBASE
FoxPro
Paradox
Microsoft Access
Microsoft Excel

AskSam has its own proprietary format to store the database using the .ASK extension. They appear to have a 256 byte header. All the DOS versions of the software use the simple BOF string of “askSam”.

hexdump -C TEST.ASK       
00000000  61 73 6b 53 61 6d 00 00  00 00 00 07 0f 01 00 00  |askSam..........|
00000010  01 00 00 00 00 01 00 05  00 37 00 02 00 00 00 01  |.........7......|
00000020  33 00 32 00 00 00 00 00  50 00 00 00 00 00 00 00  |3.2.....P.......|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000000d0  00 14 00 01 00 00 01 00  00 00 00 00 00 00 00 00  |................|
000000e0  00 00 00 00 00 01 00 00  00 00 03 1d 42 00 01 00  |............B...|
000000f0  00 13 01 00 00 00 00 01  00 00 00 00 00 00 00 00  |................|
00000100  00 00 00 00 f6 00 00 00  00 54 65 73 74 01 01 01  |.........Test...|
00000110  01 01 00

When the first Windows version came out in 1993, the header changed to the logical string:

hexdump -C DOS-WIN.ASK | head
00000000  61 73 6b 77 69 6e 00 00  00 00 00 07 0f 01 00 04  |askwin..........|
00000010  01 00 00 00 01 01 00 05  01 37 03 00 00 00 00 01  |.........7......|
00000020  64 00 32 2e 01 4e 00 00  a0 00 00 00 00 00 00 00  |d.2..N..........|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000040  00 00 00 00 00 00 00 00  00 00 00 00 00 76 43 00  |.............vC.|
00000050  00 8c 00 00 00 00 00 00  00 00 00 00 00 01 00 00  |................|
00000060  00 01 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000070  00 41 72 69 61 6c 00 72  20 4e 65 77 00 00 00 00  |.Arial.r New....|
00000080  00 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 5b 3a 00 10 10 10  |..........[:....|

With Version 2 for Windows we start seeing a slightly different header:

hexdump -C AS2W-S01.ASK 
00000000  61 73 6b 57 69 53 00 00  00 00 00 07 0f 01 00 04  |askWiS..........|
00000010  01 00 00 00 01 01 00 05  00 37 03 00 00 00 00 01  |.........7......|
00000020  c8 00 32 2f 02 4c 00 00  a0 00 00 00 00 00 00 00  |..2/.L..........|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000070  00 43 6f 75 72 69 65 72  20 4e 65 77 00 00 00 00  |.Courier New....|
00000080  00 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 5b 3a 00 10 10 14  |..........[:....|
000000a0  14 02 00 00 0a 00 00 00  00 00 00 00 00 00 00 00  |................|
000000b0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000000c0  00 00 00 00 00 00 00 00  00 00 00 60 00 00 00 00  |...........`....|
000000d0  05 00 00 00 00 00 01 00  00 00 00 00 00 00 00 00  |................|
000000e0  00 00 00 00 00 01 00 00  00 00 00 00 00 00 01 00  |................|
000000f0  00 1d 01 00 00 00 00 01  00 00 00 00 00 00 0a 00  |................|
00000100  00 00 00 00 f6 00 00 00  0a 54 65 73 74 69 6e 67  |.........Testing|
00000110  20 20 00 0a 01 09 10 c0  14 14 42 07 01           |  ........B..|

Then all samples from version 4 to the final version 7 all have the same header, although I know there is some features in the later versions that make them incompatible, there isn’t a easy way to identify the different versions after version 4.

hexdump -C Asksam4-s01.ask | head
00000000  61 73 6b 77 34 30 00 00  00 00 25 00 00 00 00 00  |askw40....%.....|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000000f0  00 00 00 00 00 00 00 00  00 00 02 00 00 00 e5 38  |...............8|
00000100  0c 3a 67 31 4d 38 dd b5  9c 65 00 00 00 00 90 01  |.:g1M8...e......|
00000110  00 00 01 01 0c 43 00 00  00 00 00 00 be 00 00 00  |.....C..........|
00000120  24 14 00 00 00 00 00 00  10 14 00 00 00 00 00 00  |$...............|
00000130  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000150  7b 4c 00 00 00 00 00 00  af 4f 00 00 00 00 00 00  |{L.......O......|

hexdump -C AskSam6-s01.ask | head
00000000  61 73 6b 77 34 30 00 00  00 00 38 00 00 00 00 00  |askw40....8.....|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000000f0  00 00 00 00 00 00 00 00  00 00 02 00 00 00 21 f1  |..............!.|
00000100  ad 41 61 9f c0 39 cd 4a  af 65 00 00 00 00 58 02  |.Aa..9.J.e....X.|
00000110  00 00 01 01 84 2e 00 00  00 00 00 00 be 00 00 00  |................|
00000120  24 14 00 00 00 00 00 00  50 13 00 00 00 00 00 00  |$.......P.......|
00000130  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000140  00 00 00 00 00 00 00 00  00 00 00 00 c6 5b 00 00  |.............[..|
00000150  ba 33 00 00 00 00 00 00  53 33 00 00 00 00 00 00  |.3......S3......|

hexdump -C AskSam7-s01.ask | head
00000000  61 73 6b 77 34 30 00 00  00 00 87 04 00 00 00 00  |askw40..........|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000000f0  00 00 00 00 00 00 00 00  00 00 02 00 00 00 b2 fd  |................|
00000100  b5 47 61 9f c0 39 5c 4b  af 65 00 00 00 00 bc 02  |.Ga..9\K.e......|
00000110  00 00 01 01 db 34 00 00  00 00 00 00 be 00 00 00  |.....4..........|
00000120  24 14 00 00 00 00 00 00  50 13 00 00 00 00 00 00  |$.......P.......|
00000130  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000150  aa 39 00 00 00 00 00 00  de 3c 00 00 00 00 00 00  |.9.......<......|

Even though everything after version 4 for Windows has the same header, files created in version 7 will not open in version 6. There must be some additional byte sequences which identify the files with the version which created the file. I have been unable to located the free askSam 7 viewer, but here is a link to the version 6 free viewer. It runs in the latest Windows OS. If you open an older version it will ask you to upgrade your file, so be sure to keep a copy of your original.

Once you have your ASK Database opened, you can export to a few formats, an RTF or a delimitated text file based on fields you have entered in the form. Word of warning, if you entered a password to protect modifying of your data in an earlier version, you have to re-enter the password in order to open/upgrade the file, but the viewer will not open password protected files, you will need the full version.

Here are two files created in AskSam 5.11 DOS, one without a password one with. You can see the 16 byte hex values from offset 41 to 57 are zeros in the file with no password and full of values in the protected file. I’m sure someone with more skills could figure out the encryption.

hexdump -C AS5-OPEN.ASK 
00000000  61 73 6b 53 61 6d 00 00  00 00 00 07 0f 01 00 00  |askSam..........|
00000010  01 00 00 00 00 01 00 05  00 37 00 02 00 00 00 01  |.........7......|
00000020  33 00 32 00 00 00 00 00  50 00 00 00 00 00 00 00  |3.2.....P.......|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000000d0  00 14 00 01 00 00 01 00  00 00 00 00 00 00 00 00  |................|
000000e0  00 00 00 00 00 01 00 00  00 00 03 1d 42 00 01 00  |............B...|
000000f0  00 13 01 00 00 00 00 01  00 00 00 00 00 00 00 00  |................|
00000100  00 00 00 00 f6 00 00 00  00 54 65 73 74 69 6e 67  |.........Testing|
00000110  01 01 00                                          |...|

hexdump -C AS5-PASS.ASK 
00000000  61 73 6b 53 61 6d 00 00  01 00 00 07 0f 01 00 00  |askSam..........|
00000010  01 00 00 00 00 01 00 05  00 37 00 02 00 00 00 01  |.........7......|
00000020  33 00 32 00 00 00 00 00  50 66 5f 14 66 42 53 40  |3.2.....Pf_.fBS@|
00000030  42 71 29 59 6a 61 62 60  6e 00 00 00 00 00 00 00  |Bq)Yjab`n.......|
*
000000d0  00 14 00 01 00 00 01 00  00 00 00 00 00 00 00 00  |................|
000000e0  00 00 00 00 00 01 00 00  00 00 03 1d 42 00 01 00  |............B...|
000000f0  00 13 01 00 00 00 00 01  00 00 00 00 00 00 00 00  |................|
00000100  00 00 00 00 f6 00 00 00  00 54 65 73 74 69 6e 67  |.........Testing|
00000110  01 01 00                                          |...|

You can check out my samples and my recommendation to PRONOM on my Github page.

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.

Presto!

January 12, 2024 by Thor Leave a comment

Working in preservation and archiving for the last few years has caused me to change a habit most people use everyday. The double-click. I am usually opening a file in a hex editor or control clicking on a file to open it in a different software application than is default. Maybe it’s just me, but having control over opening a file is essential. The thought of double-clicking on a file and the uncertainty of what is actually happening scares me a little.

Of course opening an application executable requires a double-click or a right-click/open process and from there you can open the file of your choosing. Executables are run-able files because they have the required pieces for the operating system and cpu to interpret and well; run. We need executables in order to make sense of the files we preserve. Without something to interpret our the data in our files they are just a bunch of one’s & zero’s.

Take a PDF for example. By itself, it is hard to make sense of the file. You need Acrobat Reader, or any number of other executable software programs to open and render the PDF.

But what if you could take a file and wrap it in an executable so it is all self contained, the file format and an executable in one file! No separate software needed! On the surface this seems like a great idea, which is why a few software companies had this as an option. An early competitor of PDF, Common Ground had the option to embed the DP file into a self contained viewer. Many archive software tools have the ability to make “self-extracting” executables as well. One obvious downside is being unable to execute on a different platform or a later operating system. But at the time they were very convenient.

One software in particular added the option to export a few different formats into a special wrapper making them viewable on any Windows machine.

New Soft Technology Corporation Presto! PageManager is document management software which can view many different file types. The software helps manage document and photo scanning and keep everything organized. The software often came bundled with home consumer scanners, such as the UMAX Astra scanner I bought years ago. With the Windows version of the software you can take one or more photos and “wrap” them into a Presto! Wrapper.

Once exported to a Presto! Wrapper the files within have a portable viewer wrapped up with them. One double-click and Presto!, you can view, rotate, export, and print your images. The wrapper has a your typical .EXE extension and identifies as such.

sf Presto6-s02.EXE
---
siegfried   : 1.11.0
scandate    : 2024-01-09T23:39:36-07:00
signature   : default.sig
created     : 2023-12-17T15:54:41+01:00
identifiers : 
  - name    : 'pronom'
    details : 'DROID_SignatureFile_V116.xml; container-signature-20231127.xml'
---
filename : 'Presto6-s02.EXE'
filesize : 818301
modified : 2024-01-07T23:48:01-07:00
errors   : 
matches  :
  - ns      : 'pronom'
    id      : 'fmt/899'
    format  : 'Windows Portable Executable'
    version : '32 bit'
    mime    : 'application/vnd.microsoft.portable-executable'
    class   : 
    basis   : 'extension match exe; byte match at [[0 2] [232 94]]'

hexdump -C Presto6-s02.EXE | head
00000000  4d 5a 90 00 03 00 00 00  04 00 00 00 ff ff 00 00  |MZ..............|
00000010  b8 00 00 00 00 00 00 00  40 00 00 00 00 00 00 00  |........@.......|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 e8 00 00 00  |................|
00000040  0e 1f ba 0e 00 b4 09 cd  21 b8 01 4c cd 21 54 68  |........!..L.!Th|
00000050  69 73 20 70 72 6f 67 72  61 6d 20 63 61 6e 6e 6f  |is program canno|
00000060  74 20 62 65 20 72 75 6e  20 69 6e 20 44 4f 53 20  |t be run in DOS |
00000070  6d 6f 64 65 2e 0d 0d 0a  24 00 00 00 00 00 00 00  |mode....$.......|
00000080  99 72 8f bf dd 13 e1 ec  dd 13 e1 ec dd 13 e1 ec  |.r..............|
00000090  5e 0f ef ec dc 13 e1 ec  b2 0c eb ec d6 13 e1 ec  |^...............|

The preservation of executables is, in my opinion, complicated. Running a 32 bit executable on a computer today might not even work. Then we have to get into the license of using the software and wether the license allows us to use it freely in perpetuity. So as much as this is an executable, knowing it is also a wrapper for regular images is important to know as an option for preservation. The files wrapped inside can be exported and preserved as a solution. So what makes this executable unique. Let’s look a little closer.

00005000  00 00 00 00 11 2e 40 00  00 10 40 00 80 1f 40 00  |......@...@...@.|
00005010  c0 24 40 00 00 00 00 00  00 00 00 00 00 00 00 00  |.$@.............|
00005020  50 6d 76 69 65 77 20 69  73 20 63 6c 6f 73 65 2e  |Pmview is close.|
00005030  00 00 00 00 5c 00 00 00  74 6d 70 00 5c 54 45 4d  |....\...tmp.\TEM|
00005040  50 00 00 00 20 4e 65 77  53 6f 66 74 20 56 69 65  |P... NewSoft Vie|
00005050  77 65 72 00 34 31 36 44  37 30 36 43 36 31 37 39  |wer.416D706C6179|
00005060  36 35 37 32 00 00 00 00  41 6d 70 6c 61 79 65 72  |6572....Amplayer|
00005070  00 00 00 00 70 6d 76 69  65 77 2e 65 78 65 00 00  |....pmview.exe..|
00005080  41 6d 70 6c 61 79 65 72  2e 65 78 65 20 67 72 65  |Amplayer.exe gre|
00005090  65 74 2e 69 64 20 56 00  41 6d 70 6c 61 79 65 72  |et.id V.Amplayer|
000050a0  2e 65 78 65 00 00 00 00  2e 2e 00 00 2e 00 00 00  |.exe............|
000050b0  5c 2a 2e 2a 00 00 00 00  4c 6f 63 61 6c 20 41 70  |\*.*....Local Ap|
000050c0  70 57 69 7a 61 72 64 2d  47 65 6e 65 72 61 74 65  |pWizard-Generate|
000050d0  64 20 41 70 70 6c 69 63  61 74 69 6f 6e 73 00 00  |d Applications..|
000050e0  57 72 61 70 70 65 72 00  43 45 78 70 76 77 44 6f  |Wrapper.CExpvwDo|
000050f0  63 00 00 00 43 45 78 70  76 77 56 69 65 77 00 00  |c...CExpvwView..|

It is indeed a wrapper, the header looks like any other EXE file, but a little further into the file we can see some specifics to the viewer. In all my samples I can see the string “NewsSoft Viewer“. That might be enough to distinguish it from other executables. See some samples here.

I guess part of the question is wether identifying specific software executables is needed in preservation. Arn’t they all executables and should be treated similar? This isn’t the first type of executables I have seen like this. awhile back I came across another home software which allowed you to make a slideshow, complete with audio and wrap it into an executable to put on a disk so playback was easy for the user and nothing additional was needed. The software is called Family Album Creator, use at your own risk.

PNG Plus

January 5, 2024 by Thor Leave a comment

Usually in the software world file formats are fairly efficient, the structure is meant to provide a way to store the data of the software being used. There isn’t much need to add additional unnecessary additions. This isn’t always true, but in the early days, disk space was expensive so compression and efficiency ruled. There also wasn’t much need to hide anything or complicate things. That is unless it is intended. This makes me think of two things, Polyglots and Steganography.

Steganography is the art of embedding data within an image. With digital images you can hide another image within the main image by using the most and least significant bits. Fun use of technology, but not something you normally would find in your regular desktop software.

Ange is the master at polyglots. If you haven’t watched his presentation on funky file formats, you are missing out.

.@Gynvael’s png/zip polyglot visualized (cf his article in the latest @pagedout_zine) pic.twitter.com/5BR6GLoB98
— Ange (@angealbertini) December 18, 2023

Imagine my surprise when I was researching the Picture It! software and the MIX file format only to discover Microsoft decided to make their own polyglot of sorts for their PNG Plus format which replaced the MIX format, then both obsolete when Digital Image was discontinued in 2007. The PNG Plus format was the native format for the Microsoft Picture It! and Digital Image software often found with the Microsoft Works or Digital Imaging suite of software.

According to the help within Digital Image:

The PNG Plus format uses the standard PNG extension but provides saving of layers and pages within the PNG format. Since the PNG format cannot do this natively, how did Microsoft accomplish this? Well, by throwing an OLE container into the middle of the file of course!

PNG Plus files are your regular PNG format and will identify as such. But they are just a low resolution thumbnail of the full image. Let’s take a look:

exiftool PictureIt7-s02.png 
ExifTool Version Number         : 12.70
File Name                       : PictureIt7-s02.png
File Size                       : 26 kB
File Modification Date/Time     : 2023:12:26 22:01:58-07:00
File Access Date/Time           : 2024:01:01 12:31:07-07:00
File Inode Change Date/Time     : 2023:12:26 22:01:58-07:00
File Permissions                : -rwx------
File Type                       : PNG
File Type Extension             : png
MIME Type                       : image/png
Image Width                     : 500
Image Height                    : 333
Bit Depth                       : 8
Color Type                      : RGB with Alpha
Compression                     : Deflate/Inflate
Filter                          : Adaptive
Interlace                       : Noninterlaced
SRGB Rendering                  : Perceptual
Gamma                           : 2.2
White Point X                   : 0.3127
White Point Y                   : 0.329
Red X                           : 0.64
Red Y                           : 0.33
Green X                         : 0.3
Green Y                         : 0.6
Blue X                          : 0.15
Blue Y                          : 0.06
Warning                  : [minor] Text/EXIF chunk(s) found after PNG IDAT (may be ignored by some readers)
Title                           : PictureIt7-s02
Image Size                      : 500x333
Megapixels                      : 0.167

Looks like there is some additional data after the IDAT chunk.

hexdump -C PictureIt7-s02.png | head
00000000  89 50 4e 47 0d 0a 1a 0a  00 00 00 0d 49 48 44 52  |.PNG........IHDR|
00000010  00 00 01 f4 00 00 01 4d  08 06 00 00 00 f6 13 9d  |.......M........|
00000020  37 00 00 00 01 73 52 47  42 00 ae ce 1c e9 00 00  |7....sRGB.......|
00000030  00 04 67 41 4d 41 00 00  b1 8f 0b fc 61 05 00 00  |..gAMA......a...|
00000040  00 20 63 48 52 4d 00 00  7a 26 00 00 80 84 00 00  |. cHRM..z&......|
00000050  fa 00 00 00 80 e8 00 00  75 30 00 00 ea 60 00 00  |........u0...`..|
00000060  3a 98 00 00 17 70 9c ba  51 3c 00 00 24 f4 49 44  |:....p..Q<..$.ID|
00000070  41 54 78 5e ed dd 4d a8  15 57 be 28 f0 1e 08 1e  |ATx^..M..W.(....|
00000080  e3 47 8e 49 ab c7 d8 81  03 09 41 9c 28 38 e8 80  |.G.I......A.(8..|
00000090  d0 9c 0e 08 0e 1a 11 c2  15 07 5e 5a 07 4d c7 2b  |..........^Z.M.+|

The header looks the same as any PNG file, so lets look a little further:

00002560  ff 1f fa 5f 90 66 c9 e6  ad 88 00 00 00 00 63 6d  |..._.f........cm|
00002570  4f 44 4e 88 09 c1 00 00  40 00 63 70 49 70 d0 cf  |ODN.....@.cpIp..|
00002580  11 e0 a1 b1 1a e1 00 00  00 00 00 00 00 00 00 00  |................|
00002590  00 00 00 00 00 00 3e 00  03 00 fe ff 09 00 06 00  |......>.........|
000025a0  00 00 00 00 00 00 00 00  00 00 01 00 00 00 01 00  |................|
000025b0  00 00 00 00 00 00 00 10  00 00 02 00 00 00 01 00  |................|
*
00002970  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff 52 00  |..............R.|
00002980  6f 00 6f 00 74 00 20 00  45 00 6e 00 74 00 72 00  |o.o.t. .E.n.t.r.|
00002990  79 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |y...............|
000029a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000029b0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 16 00  |................|
000029c0  05 00 ff ff ff ff ff ff  ff ff 01 00 00 00 7e 7f  |..............~.|
000029d0  3f b5 a5 f6 86 43 a1 a1  a3 02 24 d2 88 ef 00 00  |?....C....$.....|
000029e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000029f0  00 00 03 00 00 00 40 12  00 00 00 00 00 00 44 00  |......@.......D.|
00002a00  61 00 74 00 61 00 53 00  74 00 6f 00 72 00 65 00  |a.t.a.S.t.o.r.e.|
00002a10  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00003930  00 00 00 00 00 00 00 00  00 00 00 00 00 00 43 48  |..............CH|
00003940  4e 4b 49 4e 4b 20 04 00  07 00 0c 00 00 03 00 02  |NKINK ..........|
00003950  00 00 00 0a 00 00 f8 01  0c 00 ff ff ff ff 18 00  |................|
00003960  54 45 58 54 00 00 01 00  00 00 54 45 58 54 00 02  |TEXT......TEXT..|
00003970  00 00 22 00 00 00 18 00  46 44 50 50 00 00 43 00  |..".....FDPP..C.|
00003980  4f 00 4e 00 54 00 45 00  4e 00 54 00 53 00 00 00  |O.N.T.E.N.T.S...|
00003990  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000039f0  00 00 1f 00 00 00 00 0a  00 00 00 00 00 00 01 00  |................|
00003a00  43 00 6f 00 6d 00 70 00  4f 00 62 00 6a 00 00 00  |C.o.m.p.O.b.j...|
00003a10  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00004530  00 00 00 00 00 00 00 00  00 00 00 00 00 00 01 00  |................|
00004540  fe ff 03 0a 00 00 ff ff  ff ff 00 00 00 00 00 00  |................|
00004550  00 00 00 00 00 00 00 00  00 00 1a 00 00 00 51 75  |..............Qu|
00004560  69 6c 6c 39 36 20 53 74  6f 72 79 20 47 72 6f 75  |ill96 Story Grou|
00004570  70 20 43 6c 61 73 73 00  ff ff ff ff 01 00 00 00  |p Class.........|
00004580  00 00 00 00 f4 39 b2 71  00 00 00 00 00 00 00 00  |.....9.q........|
00004590  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00006570  00 00 00 00 00 00 00 00  00 00 00 00 00 00 ba 84  |................|
00006580  43 51 00 00 00 18 69 54  58 74 54 69 74 6c 65 00  |CQ....iTXtTitle.|
00006590  00 00 00 00 50 69 63 74  75 72 65 49 74 37 2d 73  |....PictureIt7-s|
000065a0  30 32 3a 70 9c 00 00 00  00 14 74 45 58 74 54 69  |02:p......tEXtTi|
000065b0  74 6c 65 00 50 69 63 74  75 72 65 49 74 37 2d 73  |tle.PictureIt7-s|
000065c0  30 32 f2 8f d5 89 00 00  00 00 49 45 4e 44 ae 42  |02........IEND.B|
000065d0  60 82                                             |`.|

What what do we have here? Near the end of the file before the IEND chunk is an OLE file with the very recognizable hex values of “D0CF11E0“. Let’s strip out the OLE file and take a look.

Path = PictureIt7-s02-ole
Type = Compound
WARNINGS:
There are data after the end of archive
Physical Size = 8704
Tail Size = 7764
Extension = compound
Cluster Size = 512
Sector Size = 64

   Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
2023-12-26 22:01:58 D....                            DataStore
2023-12-26 22:01:58 D....                            Text
                    .....         2560         2560  Text/CONTENTS
                    .....           86          128  Text/[1]CompObj
                    .....           96          128  DataStore/3
                    .....            4           64  DataStore/1
                    .....          121          128  DataStore/0
                    .....           57           64  DataStore/2
                    .....           98          128  DataStore/5
                    .....            4           64  DataStore/4
                    .....         1254         1280  DataStore/7
                    .....            4           64  DataStore/6
                    .....            4           64  DataStore/8
------------------- ----- ------------ ------------  ------------------------
2023-12-26 22:01:58               4288         4672  11 files, 2 folders

Interesting, I don’t think I have come across a standard format with a container embedded within. I have come across many OLE and ZIP containers which contain other common formats within, but this format is definitely unique. Others have added features in the IDAT chunk, such as a web shell. I am sure there are others out there. The CompObj file found within the Text directory is very similar to the Microsoft Works and Publisher format. Although trying to open the file in Publisher doesn’t work!

hexdump -C PictureIt7-s02-ole/Text/\[1\]CompObj | head
00000000  01 00 fe ff 03 0a 00 00  ff ff ff ff 00 00 00 00  |................|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 1a 00 00 00  |................|
00000020  51 75 69 6c 6c 39 36 20  53 74 6f 72 79 20 47 72  |Quill96 Story Gr|
00000030  6f 75 70 20 43 6c 61 73  73 00 ff ff ff ff 01 00  |oup Class.......|
00000040  00 00 00 00 00 00 f4 39  b2 71 00 00 00 00 00 00  |.......9.q......|
00000050  00 00 00 00 00 00                                 |......|

PRONOM uses binary and container signatures to identify file formats. Even though this file format contains a valid OLE container, because it is within a regular binary file format, I don’t believe a container signature would work. The difficulty will be to clearly identify this new format without falsely identifying a regular PNG instead. The OLE file format header is not in a consistent location to use a specific offset. Making the string a variable location can causes some undo processing, so lets look to see if there is anything else we can use to make a positive ID.

The PNG file format is based on chunks, you have to have IHDR, then an IDAT and the IEND chunk. If we take a look at a regular PNG file using a libpng tool pngcheck, we see this:

pngcheck -cvt rgb-8.png 
File: rgb-8.png (759 bytes)
  chunk IHDR at offset 0x0000c, length 13
    256 x 256 image, 24-bit RGB, non-interlaced
  chunk tEXt at offset 0x00025, length 44, keyword: Copyright
    ? 2013,2015 John Cunningham Bowler
  chunk iTXt at offset 0x0005d, length 116, keyword: Licensing
    compressed, language tag = en
    no translated keyword, 101 bytes of UTF-8 text
  chunk IDAT at offset 0x000dd, length 518
    zlib: deflated, 32K window, maximum compression
  chunk IEND at offset 0x002ef, length 0
No errors detected in rgb-8.png (5 chunks, 99.6% compression).

The required chunk are there, but a couple extra, the tEXt and iTXt, which are textual metadata you can add. Now lets look at a PNG Plus file:

pngcheck -cvt PictureIt7-s02.png         
File: PictureIt7-s02.png (26066 bytes)
  chunk IHDR at offset 0x0000c, length 13
    500 x 333 image, 32-bit RGB+alpha, non-interlaced
  chunk sRGB at offset 0x00025, length 1
    rendering intent = perceptual
  chunk gAMA at offset 0x00032, length 4: 0.45455
  chunk cHRM at offset 0x00042, length 32
    White x = 0.3127 y = 0.329,  Red x = 0.64 y = 0.33
    Green x = 0.3 y = 0.6,  Blue x = 0.15 y = 0.06
  chunk IDAT at offset 0x0006e, length 9460
    zlib: deflated, 32K window, fast compression
  chunk cmOD at offset 0x0256e, length 0
    Microsoft Picture It private, ancillary, unsafe-to-copy chunk
  chunk cpIp at offset 0x0257a, length 16384
    Microsoft Picture It private, ancillary, safe-to-copy chunk
  chunk iTXt at offset 0x06586, length 24, keyword: Title
    uncompressed, no language tag
    no translated keyword, 15 bytes of UTF-8 text
  chunk tEXt at offset 0x065aa, length 20, keyword: Title
    PictureIt7-s02
  chunk IEND at offset 0x065ca, length 0
No errors detected in PictureIt7-s02.png (10 chunks, 96.1% compression).

It looks like we have the required chunks and some textual chunks but also a couple chunks which pngcheck describes as private and identify’s them as Microsoft Picture It chunks. The cpIp chunk is the one which contains the OLE container. This is the chunk we need to identify in a signature. The problem is the offset for the cpIp chunk is not the same each time. Here is one from Digital Image 10 Pro.

  chunk cpIp at offset 0x737a7, length 245760
    Microsoft Picture It private, ancillary, safe-to-copy chunk

Significantly further in the file that the other example. These samples currently identify as PNG 1.2 files. PRONOM fmt/13 so we can use the signature and add to it, but it currently doesn’t look for IDAT only the iTXt chunk, which is probably not optimal. For PNG Plus, lets get the header which includes IHDR, IDAT, then the cpIp chunk then an end of file sequence for IEND. Take a look at my signature and samples, I am curious how many PNG Plus files are out there hidden to the world.

Turns out there is another PNG flavor which has been enhanced to allow for layers and pages. Adobe Fireworks uses a PNG format as their native format. They also use private chunks, but not within an OLE container. They use additional chunks, but before the IDAT chunk:

  chunk prVW at offset 0x00092, length 1700
    Macromedia Fireworks preview chunk (private, ancillary, unsafe to copy)
  chunk mkBF at offset 0x00742, length 72
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkTS at offset 0x00796, length 36716
    Macromedia Fireworks(?) private, ancillary, unsafe-to-copy chunk
  chunk mkBS at offset 0x0970e, length 190
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x097d8, length 1251
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x09cc7, length 1358
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0a221, length 1145
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0a6a6, length 339
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0a805, length 695
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0aac8, length 3799
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0b9ab, length 7733
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0d7ec, length 2741
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0e2ad, length 5153
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk
  chunk mkBT at offset 0x0f6da, length 10775
    Macromedia Fireworks private, ancillary, unsafe-to-copy chunk

It’s hard to know which each of the chunks are for and if they are all required for the Fireworks PNG format. From the book on PNG.

In addition to supporting PNG as an output format, Fireworks actually uses PNG as its native file format for day-to-day intermediate saves. This is possible thanks to PNG’s extensible “chunk-based” design, which allows programs to incorporate application-specific data in a well-defined way. Macromedia has embraced this capability, defining at least four custom chunk types that hold various things pertinent to the editor. Unfortunately, one of them (pRVW) violates the PNG naming rules by claiming to be an officially registered, public chunk type, but this was an oversight and should be fixed in version 2.0.