Independent JPEG Group's free JPEG software ------------------------------------------- This package contains C software to implement JPEG image compression and decompression. JPEG is a standardized compression method for full-color and gray-scale images. JPEG is intended for "real-world" scenes; cartoons and other non-realistic images are not its strong suit. JPEG is lossy, meaning that the output image is not identical to the input image. The user can trade off output image quality against compressed file size by adjusting a compression parameter. The distributed programs provide conversion between JPEG "JFIF" format and image files in PBMPLUS PPM/PGM, GIF, BMP, and Targa file formats. The core compression and decompression library can easily be reused in other programs, such as image viewers. The package is highly portable C code; we have tested it on many machines ranging from PCs to Crays. We are releasing this software for both noncommercial and commercial use. Companies are welcome to use it as the basis for JPEG-related products. We do not ask a royalty, although we do ask for an acknowledgement in product literature (see the README file in the distribution for details). We hope to make this software industrial-quality --- although, as with anything that's free, we offer no warranty and accept no liability. For more information, contact jpeg-info@uunet.uu.net. Contents of this directory -------------------------- jpegsrc.vN.tar.gz contains source code, documentation, and test files for release N. jpegaltui.vN.tar.gz contains source code for an alternate user interface for cjpeg/djpeg. wallace.ps.gz is a PostScript file of Greg Wallace's introductory article about JPEG. This is an update of the article that appeared in the April 1991 Communications of the ACM. jpeg.documents.gz tells where to obtain the JPEG standard and documents about JPEG-related file formats. jfif.ps.gz is a PostScript file of the JFIF (JPEG File Interchange Format) format specification. jfif.txt.gz is a plain text transcription of the JFIF specification; it's missing a figure, so use the PostScript version if you can. TIFFTechNote2.txt.gz is a draft of the proposed revisions to TIFF 6.0's JPEG support. pm.errata.gz is the errata list for the first printing of the textbook "JPEG Still Image Data Compression Standard" by Pennebaker and Mitchell. jdosaobj.zip contains pre-assembled object files for JMEMDOSA.ASM. If you want to compile the IJG code for MS-DOS, but don't have an assembler, these files may be helpful. All files are compressed with gzip (GNU zip), except jdosaobj.zip which is compressed with Info-Zip's zip (compatible with PKUNZIP). If you don't have gzip, uunet's FTP server can decompress the files for you on-the-fly. Just fetch the given file name minus ".gz".