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JPEGsnoop - Source Code

JPEGsnoop is released as Open Source!

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JPEGsnoop is now Open Source!

I'm happy to announce that I have now released JPEGsnoop source code to the open source community. I am hoping that this will enable others to add value in the project in new ways, in addition to helping those who are learning to write their own JPEG decoders

After researching many of the options pertaining to how the source code was released, here are the details:

Considerations for Open Source

After analyzing digital images for years and developing JPEGsnoop in my spare time, I decided to explore the possibility of releasing the source code to the Open Source community for further development. I was looking to my readers to provide their input in how to best approach this transition.

There are many wonderful application developers out there who are more than capable of improving upon the features and user interface, and I'd like to give everyone the opportunity.

The Source Code

  • JPEGsnoop is written in Visual C++
  • JPEGsnoop uses Windows MFC framework
  • No 3rd party libraries are required: All image decode/display, EXIF decode, etc. are written independently.
  • An extensive database of camera signatures is also included with the source code.

Are you interested in improving JPEGsnoop?

Please let me know if you are a programmer with ideas that you'd like to roll into future releases of JPEGsnoop.

Porting JPEGsnoop to Mac and/or LINUX

Quite frequently, I have been receiving requests to port JPEGsnoop to other operating systems. In most cases, the User Interface code has been reasonably well separated from the primary analysis code, so a port should be relatively easy.

 

Reader's Comments:

Please leave your comments or suggestions below!
2013-03-13be.jpeg
 Could you please update the sourceforge code to the newest version. Preferably also in a zip (outside of the SVN rep). Thanks!
 Hi -- for sure. I had migrated to a new computer (what improvement an SSD makes!) but overlooked re-instantiating the SVN linkage. I will aim to get the repository caught up soon. Thanks for the reminder! [UPDATE 2013/05/14]: The SVN repository is now current.
2013-01-11anitha.ko
 very useful information....if anybody has matlab code for jpeg compression....pls help me out....
2013-01-05Hoogo
 Wonderful tool :)

Faststone can create Jpgs with different color spaces than YCbCr, like RGB or YCbCrK. I don't know if a RGB-Jpg is still standard, at least all other programs I checked so far can display it correctly.

*** Marker: SOF2 (Progressive DCT) (xFFC2) ***
Number of Img components = 3
Component[1]: ID=0x52, Samp Fac=0x11 (Subsamp 1 x 1), Quant Tbl Sel=0x00 (?]
Component[2]: ID=0x47, Samp Fac=0x11 (Subsamp 1 x 1), Quant Tbl Sel=0x00 (?]
Component[3]: ID=0x42, Samp Fac=0x11 (Subsamp 1 x 1), Quant Tbl Sel=0x00 (?]
 Thanks Hoogo -- The tool doesn't detect or handle other color spaces at the moment (other than YCC). I have only rarely ever come across a file other than YCC (or possibly CMYK for printing), but it is on the feature request list. I think it should be relatively easy to extend to support RGB at least. thanks
2012-10-24dan
 Great code, very useful. The signature repository in Signatures.inl in svn is getting a little old. Any chance you could update it with any new ones you've collected? Or a link to a page that generates them from the mysql database? Thanks a lot for all your hard work!
 Hi Dan -- thanks for the feedback! Yes, I have slowed down on my signature updates mainly because my newborn baby has taken up the majority of my spare time :) I think your suggestion of opening up the database might be a good idea. The database currently has almost 28,000 [unverified] entries.

What I would need to decide is: how to provide access (web rendered output, signature file format or DB queries), how to manage server load, and what filtering should be done (if any). If anyone has any ideas, please let me know. Just producing a "JPEGsnoop_db.dat" file to download wouldn't work since it wouldn't have undergone any filtering.
2012-10-05mastana
 brilliant page.
2011-11-13Anto
 Hi, I think I've find a bug in this program.
If I create a new file and rename it (changing the extension) and then make changes with paint, the final image does not recognize in JPEGsnoop.
"JPEGsnoop 1.5.2 by Calvin Hass
http://www.impulseadventure.com/photo/
-------------------------------------

Filename: [C: / Users / Antonio / Desktop / $ RUDWR80.jpg]
Filesize: [1414710] Bytes

Start Offset: 0x00000000
NOTE: File with JPEG markers did not start. Consider using [Tools-> Img Search Fwd] to locate embedded JPEG. "
 Hi Anto -- I can't seem to recreate the issue you noted here. Could you give me more specifics on what the file renaming changed (ie. before and after, including extension)? Thanks
2010-11-06Adrien
 Yeah Sourceforge guys... or Google Code.
 I've posted it to SourceForge now! I'll be posting links to everything shortly.
2010-10-27Jim
 1. You might want to mention somewhere that the source code cannot be compiled with Visual Studio Express Edition, because it requires MFC libraries (which included only in VS Standard Edition and above).

2. You're not supposed to commit executable files to source control (Release/JPEGsnoop.exe). The common practice is to tell SVN to ignore 'Release' and 'Debug' folders (if you're using TortoiseSVN, right click on those folders, TSVN -> add to ignore list -> the name of the folder). You can also do this for other auto-generated files such as *.ncb etc.
 Great points!! I am new to this process, so I'll fix the second one soon. As for the first item, I'll see if I can find some place to put intro text for the source (didn't see any in SourceForge), so I'll probably just put it in a README within the vault.

Thanks!

UPDATE: I have now corrected the repository to remove binaries.
2010-10-17borisk
 If you are open sourcing it then I would recommend Google Code as your repository. I have had better experience using it than Sourceforge. I hope you do eventually decide to open source, as it will be fascinating to examine how your program works!
 Thanks! In the end I went with Sourceforge -- and am in the process of tidying up the codebase. I am happy to give others an opportunity to enhance what I have put together. Hopefully others will take advantage of this and introduce new capabilities.
 
2010-10-14Yaroslav
 I would like to encourage you to move forward.

Sometimes I need advanced parsing visualization and picture pixels zoom. This capabilities could be added in future by enthusiasts, probably I'll do it.

I believe, that port to Linux is required as well.
I would advise to merge Image debugger to JPEGSnoop
http://www.billbaxter.com/projects/imdebug/

As far as it is built with wxWidgets - it could be a choice of graphic library to use.

See you in repository ;)
 Thanks Yaroslav...
2010-09-15Michael Soegtrop
 Dear Calvin,

JPEGSnoop is pretty good as it is, but I would definitly add some features here and there as I need them when you release it to open source. I might e.g. think about adding support for progressive JPEGs. I would prefer LGPL because it might give the code a broader user base, but GPL would also be fine. I would prefer sourceforge because it is not commercial like google, but I don't have a strong opinion on this either.

Best regards,

Michael
 Thanks Michael for the suggestions!
2010-09-13Olga
 hi man, how can i get sources of JPEGSnoop?
 Source code is currently in the process of being made available.... stay tuned!
2010-08-18lifan
 very good!
2010-08-09Vincent
 Great news. I am willing to see jpegsnoop run on linux.
2010-05-30Thomas
 Hi

Somebody highlight me this wikipedia entry (it may help you) :

http://en.wikipedia.org/wiki/Comparison_of_open_source_software_hosting_facilities
 Thanks, that's really useful!
2010-04-24mark cox
 I would consider the LGPL to be a good compromise because it would allow code to be factored out into a library that could then have multiple frontends or application users. Also, i prefer googlecode over sourceforge. i find it so much simpler to use.
 Thanks Mark!
2010-04-13Jim
 I also recommend Sourceforge.
2010-04-11Thomas
 Hello

Great news, releasing such software is great for people trying to understand jpeg standard as i am at the moment :)

License and depot host site depend of what you want to do now!
If you still want to manage yourself patch, bug and keep source a depot impulseadventure is the best solution. But you will have to install yourself all the web stuff, and you will probably never want to share this management with someone else that you probably will never meet.

If you want at the end that somebody else handle all this software life. Depot on remote server is probably the best. They provide bugzilla database for bug tracking and feature request, mailing list services, forum ... You are free to use it. There is some permission management too this allow to share project management : commit, release, forum moderation ...
Which of google code, sourceforge, freahmeat ... Well ...
Google "Don't be evil" (http://en.wikipedia.org/wiki/Don%27t_be_evil) Some people think they are ...
Sourceforge i read a day the same about them.

Once you publish your code the only thing that protect you and your work is the licence.
If you don't care about what people will do with it, BSD licence is great. Eventually somebody will make money with it :)
If you choose a more restrictive licence (ie GPL ), you force people who use your work to share with the community their personnal work.

So it really depend of which project future you want to go.
 Thanks Thomas. Given the number of people that have downloaded and use JPEGsnoop, it is difficult for me to keep up with the magnitude of development feature requests & support. Some features, such as the signature matching / database, could use some collaborative input into how it can be made more useful / accurate. I also recognize my limitations in user interface development, which again reinforces the benefit of opening it up for others.

I am inclined to migrate the hosting off-site (eg. to sourceforge) so that I can leverage the bugzilla, CVS, support forums and greater visibility. I don't have any problem with others taking control over the direction of the program, though I am still keen to keep involved in the development & ideas for the future.

Regarding the licensing, my personal preference is to help increase the sharing & learning with others, which seems more in line with a GPL-type license. I will need to spend some time looking at this in greater detail, but that's the direction I'm currently leaning.
2010-04-10Rez
 Lessee, the other question, about opensource licensing. There are a variety available, some better than others. I'm sure you're aware of them, but here's my opinion:

If you want to enforce a future of opensource, then GPL2 is probably a good choice and is pretty well known and understood by now.

If you want to make it as free as possible for the world to use (including closed-source projects), while retaining acknowledgment of its origins, then the BSD lic. works.

Personally I would *not* go with the GPL3 lic. as it gets into political motivations that are, IMO, quite at odds with the whole philosophy of shared source.
 Great input... I am relatively new to the licensing terms, so I will need to dig into this carefully.
2010-04-10Rez
 Sourceforge is probably the best known and most accessable distribution point for opensource stuff. Most likely to show up in a search for a particular type of program, too. So it is what I'd recommend, at least from userland.

I'd be glad to see it happen as one of my small ongoing fears is that source will be lost forever for unique programs (it has happened before), which are then frozen in time. So thank you for considering this method of assuring JpegSnoop's ongoing future.
 Thanks Rez! I would love to see the program continue development as I have a huge list of interesting features that people have requested but only a limited amount of time available.

 

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