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Wordsmith GIF limitations in cjpeg.1/djpeg.1
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dcommander committed Feb 18, 2016
1 parent aefd8b7 commit 83aeb7b
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6 changes: 3 additions & 3 deletions cjpeg.1
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.TH CJPEG 1 "17 December 2015"
.TH CJPEG 1 "17 February 2016"
.SH NAME
cjpeg \- compress an image file to a JPEG file
.SH SYNOPSIS
Expand Down Expand Up @@ -337,11 +337,11 @@ Independent JPEG Group
This file was modified by The libjpeg-turbo Project to include only information
relevant to libjpeg-turbo, to wordsmith certain sections, and to describe
features not present in libjpeg.
.SH BUGS
.SH ISSUES
Support for GIF input files was removed in cjpeg v6b due to concerns over
the Unisys LZW patent. Although this patent expired in 2006, cjpeg still
lacks GIF support, for these historical reasons. (Conversion of GIF files to
JPEG is usually a bad idea anyway.)
JPEG is usually a bad idea anyway, since GIF is a 256-color format.)
.PP
Not all variants of BMP and Targa file formats are supported.
.PP
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14 changes: 8 additions & 6 deletions djpeg.1
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.TH DJPEG 1 "26 June 2015"
.TH DJPEG 1 "17 February 2016"
.SH NAME
djpeg \- decompress a JPEG file to an image file
.SH SYNOPSIS
Expand Down Expand Up @@ -281,8 +281,10 @@ Independent JPEG Group
This file was modified by The libjpeg-turbo Project to include only information
relevant to libjpeg-turbo, to wordsmith certain sections, and to describe
features not present in libjpeg.
.SH BUGS
To avoid the Unisys LZW patent,
.B djpeg
produces uncompressed GIF files. These are larger than they should be, but
are readable by standard GIF decoders.
.SH ISSUES
Support for compressed GIF output files was removed in djpeg v6b due to
concerns over the Unisys LZW patent. Although this patent expired in 2006,
djpeg still lacks compressed GIF support, for these historical reasons.
(Conversion of JPEG files to GIF is usually a bad idea anyway, since GIF is a
256-color format.) The uncompressed GIF files that djpeg generates are larger
than they should be, but they are readable by standard GIF decoders.

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