Lincomatic e3krstrip

Canon EOS-300D/Kiss/Digital Rebel Preview Image Stripper for Microsoft® Windows®

The JPEG files output by the Canon EOS-300D contain an extra 1536x1024 image which is essentially useless, because it is only used in-camera for preview purposes. The preview image allows the camera to instantly playback the images, unlike the EOS-10D which first displays a coarse preview, and then refines it. This extra preview image not only wastes space in-camera, so you get fit less photos on your storage card than otherwise would be possible, but it also wastes space after you copy the images to your PC.  Although nothing can be done about the wasted space in-camera, we can at least save storage space after the image is downloaded into a computer.

Here are the contents of a sample image file, taken in large JPEG mode:

Original File Size: 3161798 bytes

As we can see from the example, 14% of the space is wasted! e3krstrip reclaims the wasted space by stripping the preview image from the files.   The algorithm is completely LOSSLESS. All remaining original data are preserved.

If the target file contains no preview image, then it is left untouched. For safety, if a preview image is found, it first writes a temporary file, and only overwrites the original after it determines that no errors were encountered. The creation time/date of the original is preserved.  While I have put as much reasonable checking into the program as possible, it might be wise for you to copy your files, run e3krstrip on the copies, and check them before overwriting the originals.  The program ignores all .JPG files which don't contain a valid model string for the EOS-300D in the EXIF data, so you don't have to worry about corrupting any .JPG files which were created by other programs or cameras..

This program is free, but it's copyrighted.  It comes with NO WARRANTY, EXPRESS OR IMPLIED.  Use at your own risk.

Usage: e3krstrip targetdirectory

Example:  e3krstrip c:\photos
recurses through all subdirectories of C:\photos and strips the previews from all the .JPG files that it encounters.

Download Lincomatic e3krstrip V1.02 (stable):  e3krstrip.zip

Download V1.02b: e3krstrip10b.zip
WARNING: V1.20b is experimental and HAS NOT BEEN TESTED THOROUGHLY.   I have run it through my entire 4GB archive of images and so far it works ok.  This version uses jpegtran to automatically LOSS-LESSLY rotate the main images (the thumbnail is not rotated).  Strangely, Canon Fileviewer seems to ignore the Orientation parameter in the EXIF data, because after rotation, it displays the wrong orientation.  So far, WinXP, IrfanView, and ACDSee all display the correct orientation after rotation.

Please send any feedback to:  lincomatic AT yahoo.com

ChangeLog:

V1.02b: 20031221

- added experimental automatic loss-less rotation via jpegtran

V1.02: 20031220

- fixed compatibility problem w/ European and Japanese cameras.
- changed marker parsing algorithm because old one didn't work on all files

V1.01: 20031219

- fixed compatbility problem with Win9x/Me - couldn't overwrite original file
- changed temporary filename from .tmp to .stripped

V1.0 : 20031218

- Initial Release

Copyright © 2003 Sam C. Lin