Near lossless compression with pngquant command PNG image size reduced by about 70%

1. Installation

wget http://pngquant.org/pngquant-2.8.2-src.tar.gz

Tar-xzf pngquant-2.8.2-src.tar.gz

CD pngquant-2.8.2

Installation dependency: Yum install Libpng-devel

./configure

Make && make install

OK, the installation is complete.

Pngquant-h See if normal, if reported: Pngquant:error while loading shared libraries:liblcms2.so.2:cannot open shared object File:no su CH File or directory

Re-install LIBLCMS2, yum install http://pkgrepo.linuxtech.net/el6/release/x86_64/liblcms2-2.4-1.el6.x86_64.rpm solve

Options

See for full pngquant -h list of options.

--ext new.png

Set custom extension for output filename. By default -or8.png or is -fs8.png used.

--quality min-max

Instructs to use the pngquant least amount of colors required to meet or exceed the max quality. If conversion results in quality below min the quality the image won ' t is saved (if outputting to stdout, 24-bit Origina L'll be output) and would pngquant exit with status code 99.

min maxand is numbers in range 0 (worst) to [perfect], similar to JPEG.

pngquant --quality=65-80 image.png

--speed N, -sN

Speed/quality trade-off from 1 (brute-force) to ten (fastest). The default is 3. Speed ten have 5% lower quality, but is 8 times faster than the default.

--iebug

Workaround for IE6, which only displays fully opaque pixels. Would make pngquant almost-opaque pixels fully opaque and would avoid creating new transparent colors.

--version

Print version information to stdout.

-

Read image from stdin and send result to stdout.

--

Stops processing of arguments. This allows use of the file names that start with - . If you ' re using pngquant in a script, it's advisable to put the this before file names:

pngquant $OPTIONS -- "$FILE"

Near lossless compression with pngquant command PNG image size reduced by about 70%