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authorTrevor Johnson <trevor@FreeBSD.org>2004-04-10 17:11:02 +0000
committerTrevor Johnson <trevor@FreeBSD.org>2004-04-10 17:11:02 +0000
commitf844f89eae41ff16153dc2b25c0706c6dffbd205 (patch)
tree5c623b2396dd5d45381df003d7c24921239c9eaa /graphics/pngquant
parentAdd kino. (diff)
Cram into 80 columns by 24 rows.
Notes
Notes: svn path=/head/; revision=106669
Diffstat (limited to 'graphics/pngquant')
-rw-r--r--graphics/pngquant/pkg-descr30
1 files changed, 7 insertions, 23 deletions
diff --git a/graphics/pngquant/pkg-descr b/graphics/pngquant/pkg-descr
index 47d9294728a1..5733a80fe1fb 100644
--- a/graphics/pngquant/pkg-descr
+++ b/graphics/pngquant/pkg-descr
@@ -1,40 +1,24 @@
-pngquant is a simple tool with one purpose: convert 32-bit RGBA PNGs into
-8-bit RGBA-palette PNGs (or fewer than 8 bits, if you want), via quantization
-and either ordered or diffusion (Floyd-Steinberg) dithering. The fact that
-you can also use it on RGB or even palette images (e.g., to further color-
-reduce them to 16 colors or whatever) is just a nice little bonus.
-
-The current version is fully functional in the sense that it can do:
-
+The pngquant utility converts 32-bit RGBA PNGs to 8-bit RGBA-palette PNGs (or
+fewer than 8 bits, if you want), via quantization and ordered or diffusion
+(Floyd-Steinberg) dithering. You can also use it on RGB or even palette images
+(for example, to further color-reduce them to 16 colors). It does:
- nice reduction of all PNG image types to 256-color (or smaller) palette
- automatic optimization of tRNS chunks
- batch conversion of multiple files (e.g., "pngquant 256 *.png")
- Unix-style command-line filtering (e.g., "... | pngquant 16 | ...")
-
-...on at least Unix and Win32. It should be pretty easy to port to almost
-any other platform with a command-line interface and unstructured (stream-
-oriented) files, including VMS but probably not VM or MVS.
-
It does still lack a few features:
-
- no ancillary chunk preservation (except gAMA)
- no preservation of significant-bits info after rescaling (sBIT chunk)
- no mapfile support
- no "native" handling of 16-bit-per-sample files or gray+alpha files
- (i.e., all samples are truncated to 8 bits and all images are promoted
+ (all samples are truncated to 8 bits and all images are promoted
to RGBA before quantization)
-
-These issues will be addressed in a post-1.0 release.
-
By the way, be sure to check "before" and "after" file sizes, preferably with
pngcrush (http://pmt.sourceforge.net/pngcrush/); dithered palette images may
-be four times smaller to begin with, but they don't compress nearly as well
+be four times smaller to begin with, but they do not compress nearly as well
as grayscale and truecolor images. Some images, such as Henri Sivonen's alpha
button (http://www.pp.htv.fi/hsivone1/css-test/bitmapstyle.html), can be made
smaller as full 32-bit RGBA images (4076 bytes in this case) than as either
FS-dithered palette (4550 bytes) or ordered-dither palette (4482 bytes) images.
-
WWW: http://www.libpng.org/pub/png/apps/pngquant.html
-
-Greg Roelofs
-newt@pobox.com
+Greg Roelofs <newt@pobox.com>