JPEG, Graphics, Library supporting the JPEG format Installation The best way to build the Jpeg library is currently to execute the modified DCL procedure make_vms.com from this server. This procedure will examine the system environment, create a suitable jconfig.h file and use the available tools (MMS/MMK, C compiler) to rebuild the sources. Make_vms.com currently accepts the following options in arbitrary order: DEBUG Build the library with debug information and without optimization. lopts= Options to pass to the link command e.g. lopts=/tracback ccopt= Options to pass to the C compiler e.g. ccopt=/float=ieee LINK Do not compile, just link Jpeg example programs and shareable image CC= Force usage of the given C compiler over the intrinsic selection (which is DEC C, VAX C, and finally GNU C). An object library of the Jpeg code will be generated in any case, on OpenVMS Alpha additionally a shareable image will be created. It also ensures a working copy of testimgp.jpg is available for testing. Test problems with progressive Jpeg file In case you do experience problems with the check for the progressive Jpeg test image (i.e. Backup /Compare/Log testimgp.jpg. testoutp.jpg.) you most probably packed the original file testimgp.jpg directly with Zip. This causes an extra byte to turn up at the end of the file after unpacking. I suspect this is a bug and have reported this to the Zip/UnZip developers. To circumvent this the archive from this server contains a backup saveset with this specific image. Package contents The main result of the compilation is the object library libjpeg.olb (OpenVMS Alpha: jpegshr.exe), which other applications need to link against. Additionally five small executable programs are created: CJPEG Compress an image file to a JPEG file. Supported input formats: PPM (PBMPLUS color format), PGM (PBMPLUS gray-scale format), BMP, Targa DJPEG Decompress a JPEG file to an image file. Supported output formats: PBMPLUS (PPM/PGM), BMP, GIF, Targa JPEGTRAN Jpegtran translates JPEG files from one variant of JPEG to another, for example from baseline JPEG to progressive JPEG. RDJPGCOM Display text comments from a JPEG file WRJPGCOM Insert text comments into a JPEG file The latest version of the OpenVMS port of the JPEG library should always be accessible via http://www.decus.de:8080/www/vms/sw/jpeg.htmlx