pkgsrc/graphics/ljpeg
wiz 82b911b3a0 Initial import of ljpeg-1.0 (from pkgsrc-wip):
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.
2003-12-21 21:30:14 +00:00
..
patches Initial import of ljpeg-1.0 (from pkgsrc-wip): 2003-12-21 21:30:14 +00:00
DESCR Initial import of ljpeg-1.0 (from pkgsrc-wip): 2003-12-21 21:30:14 +00:00
distinfo Initial import of ljpeg-1.0 (from pkgsrc-wip): 2003-12-21 21:30:14 +00:00
Makefile Initial import of ljpeg-1.0 (from pkgsrc-wip): 2003-12-21 21:30:14 +00:00
PLIST Initial import of ljpeg-1.0 (from pkgsrc-wip): 2003-12-21 21:30:14 +00:00