./graphics/ljpeg, Lossless JPEG codec

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Branch: CURRENT, Version: 1.0, Package name: ljpg-1.0, Maintainer: pkgsrc-users

In 1992, a joint ISO/CCITT committee known as JPEG (Joint Photographic Experts
Group) established and published the first draft international standard (DIS)
for compressing continuous-tone still images, both grayscale and color. JPEG has
defined four mode of operations, summarized them as follows:
(1) Sequential encoding: each image component is encoded in a single
left-to-right, top-to-bottom scan;
(2) Progressive encoding: the image is encoded in multiple scans for
applications in which transmission time is long, and the viewer prefers to
watch the image build up in multiple coarse-to-clear passes;
(3) Lossless encoding: the images is encoded to guarantee exact recovery of
every source image sample value (even though the result is low compression
compared to the lossy modes);
(4) Hierarchical encoding: the image is encoded at multiple resolutions so that
lower-resolution versions may be accessed without first having to decompress
the image at its full resolution.
Our lossless JPEG encoding program has an automatic prediction selection value
(PSV) selector which selects the best PSV among a user provided or default set
of PSVs. This selector guarantees the best compression ratio for lossless JPEG.

The encoding program "pnmtoljpg" compresses a Portable Pixmap or Portable
Graymap image to a lossles JPEG (ljpg) image using the JPEG standard (DIS)
lossless mode of operation. The decoding program "ljpgtopnm" decodes a ljpg
image to either a Portable Pixmap or Portable Graymap image depending on the
number of color components stored in the ljpg image file.


Required to build:
[pkgtools/cwrappers]

Master sites:

Version history: (Expand)

CVS history: (Expand)


   2021-10-26 12:47:26 by Nia Alarie | Files touched by this commit (800) 
Log message:
graphics: Replace RMD160 checksums with BLAKE2s checksums

All checksums have been double-checked against existing RMD160 and
SHA512 hashes
   2021-10-07 16:13:27 by Nia Alarie | Files touched by this commit (800) 
Log message:
graphics: Remove SHA1 hashes for distfiles
   2021-04-21 17:30:41 by Thomas Klausner | Files touched by this commit (1) 
Log message:
ljpeg: remove dead download site.
   2015-11-03 22:34:36 by Alistair G. Crooks | Files touched by this commit (610) 
Log message:
Add SHA512 digests for distfiles for graphics category

Problems found with existing digests:
	Package fotoxx distfile fotoxx-14.03.1.tar.gz
	ac2033f87de2c23941261f7c50160cddf872c110 [recorded]
	118e98a8cc0414676b3c4d37b8df407c28a1407c [calculated]
	Package ploticus-examples distfile ploticus-2.00/plnode200.tar.gz
	34274a03d0c41fae5690633663e3d4114b9d7a6d [recorded]
	da39a3ee5e6b4b0d3255bfef95601890afd80709 [calculated]

Problems found locating distfiles:
	Package AfterShotPro: missing distfile AfterShotPro-1.1.0.30/AfterShotPro_i386.deb
	Package pgraf: missing distfile pgraf-20010131.tar.gz
	Package qvplay: missing distfile qvplay-0.95.tar.gz

Otherwise, existing SHA1 digests verified and found to be the same on
the machine holding the existing distfiles (morden).  All existing
SHA1 digests retained for now as an audit trail.
   2013-04-07 22:49:45 by Blue Rats | Files touched by this commit (91) 
Log message:
Edited DESCR in the case of:
 File too long (should be no more than 24 lines).
 Line too long (should be no more than 80 characters).
 Trailing empty lines.
 Trailing white-space.
Trucated the long files as best as possible while preserving the most info
contained in them.
   2012-10-06 16:11:27 by Aleksej Saushev | Files touched by this commit (427) 
Log message:
Drop superfluous PKG_DESTDIR_SUPPORT, "user-destdir" is default these days.
   2009-10-29 23:34:33 by Tobias Nygren | Files touched by this commit (3) 
Log message:
Support DESTDIR and PKGMANDIR
   2009-06-14 19:59:32 by Joerg Sonnenberger | Files touched by this commit (263) 
Log message:
Remove @dirrm entries from PLISTs