gstreamer/gst/dvbsubenc/libimagequant/CHANGELOG

version 2.4
-----------
 - fixed remapping of bright colors when dithering
 - added libimagequant API to add fixed preset colors to the palette

version 2.3
-----------
 - added ./configure script for better support of Intel C compiler and dependencies [thanks to pdknsk]
 - tweaked quality metric to better estimate quality of images with large solid backgrounds [thanks to Rolf Timmermans]
 - atomic file saves and fixed --skip-if-larger
 - avoid applying quality setting to images that use palette already
 - preserving standard PNG chunks (requires libpng 1.6)
 - deprecated libpng 1.2 support

version 2.2
-----------
 - preserving of unknown PNG chunks (enables optimized Android 9-patch images)
 - improved color profile support: cHRM & gAMA as alternative to ICC profiles, OpenMP acceleration
 - improved support for Intel C Compiler, speedup in 32-bit GCC, and some workarounds for Visual Studio's incomplete C support

version 2.1
-----------
 - option to save files only if they're compressed better than the original
 - option to generate posterized output (for use with 16-bit textures)
 - support for ICC profiles via Little CMS library

version 2.0
-----------
 - refactored codebase into pngquant and standalone libimagequant
 - reduced memory usage by further 30% (and more for very large images)
 - less precise remapping improving speed by 25% in higher speed settings
 - --output option for writing converted file under the given path
 - light dithering with --floyd=0.5
 - fixed regression in dithering of alpha channel

version 1.8
-----------
 - min/max quality option (number of colors is automatically adjusted for desired quality level)
 - switched option parsing to getopt_long (syntax such as -s1 and --ext=ext is supported)
 - significantly improved performance thanks to custom partial sorting
 - optional Cocoa (Mac OS X) image reader for color profile support
 - reduced memory usage by 20%
 - remapping improved for very low number of colors

version 1.7
-----------
 - new, accurate RGBA color similarity algorithm
 - change of optional SSE3 code to SSE2 that is always enabled on x86-64
 - optional OpenMP-based parallelisation of remapping
 - changed long options to use double hyphen (-force to --force) [thanks to Jari Aalto]

version 1.6
-----------
 - novel dithering algorithm that doesn't add noise unless necessary
 - perceptual weighting of colors taking into account edges and noise
 - much faster remapping
 - improved portability, makefiles and man page

version 1.5
-----------
 - palettes postprocessed with Voronoi iteration
 - better RGBA color similarity algorithm and Floyd-Steinberg remapping
 - SSE optimisations

version 1.4
-----------
 - median cut is applied many times in a feedback loop
 - speed/quality trade-off option
 - faster remap of transparent areas

version 1.3
-----------
 - significant changes to the algorithm: use of variance
   to find largest dimensioin and to split most varying boxes
 - use of premultiplied alpha for color blending
 - conversion of output to gamma 2.2

version 1.2
-----------
 - color computation done in floating point
 - gamma correction applied
 - dropped support for very old systems & compilers

version 1.1
-----------
 - alpha-sensitive color reduction and dithering
 - support -- and - arguments in command line
 - number of colors optional (defaults to 256)
 - increased maximum number of colors in histogram

version 1.0
-----------
 - cleaned up Makefile.unx (better gcc optimizations, "clean" target)
 - recompiled binaries with zlib 1.1.4

version 0.95
------------
 - fixed Win32 filter bug (binary mode for stdin/stdout)
 - fixed cosmetic "choosing colors" verbosity buglet
 - fixed palette-size bug when number of colors in image < number requested
 - fixed sample-depth bug (png_set_packing() not retroactively smart)

version 0.91
------------
 - fixed some verbose/non-verbose oopers
 - fixed Win32 (MSVC) portability issues (getpid(), random(), srandom())
 - added Makefile.w32 for MSVC (tested with 5.0)

version 0.90
------------
 - added support for multiple files on command line
 - changed stdin support to write PNG stream to stdout (not "stdin-fs8.png")

version 0.75
------------
 - added support for any type of input file [Glenn Randers-Pehrson]
 - fixed palette-(re)scaling bug
 - added -verbose and -quiet options (default now is -quiet)
 - added palette-remapping to minimize size of tRNS chunk
 - made Floyd-Steinberg dithering default
 - changed output naming scheme to -fs8.png and -or8.png (FS or ordered dither)

version 0.70
------------
 - first public release
dvbsubenc: Add DVB Subtitle encoder Add an element that converts AYUV video frames to a DVB subpicture stream. It's fairly simple for now. Later it would be good to support input via a stream that contains only GstVideoOverlayComposition meta. The element searches each input video frame for the largest sub-region containing non-transparent pixels and encodes that as a single DVB subpicture region. It can also do palette reduction of the input frames using code taken from libimagequant. There are various FIXME for potential improvements for now, but it works. Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1227> 2020-04-07 11:47:22 +00:00			`version 2.4`
			`-----------`
			`- fixed remapping of bright colors when dithering`
			`- added libimagequant API to add fixed preset colors to the palette`

			`version 2.3`
			`-----------`
			`- added ./configure script for better support of Intel C compiler and dependencies [thanks to pdknsk]`
			`- tweaked quality metric to better estimate quality of images with large solid backgrounds [thanks to Rolf Timmermans]`
			`- atomic file saves and fixed --skip-if-larger`
			`- avoid applying quality setting to images that use palette already`
			`- preserving standard PNG chunks (requires libpng 1.6)`
			`- deprecated libpng 1.2 support`

			`version 2.2`
			`-----------`
			`- preserving of unknown PNG chunks (enables optimized Android 9-patch images)`
			`- improved color profile support: cHRM & gAMA as alternative to ICC profiles, OpenMP acceleration`
			`- improved support for Intel C Compiler, speedup in 32-bit GCC, and some workarounds for Visual Studio's incomplete C support`

			`version 2.1`
			`-----------`
			`- option to save files only if they're compressed better than the original`
			`- option to generate posterized output (for use with 16-bit textures)`
			`- support for ICC profiles via Little CMS library`

			`version 2.0`
			`-----------`
			`- refactored codebase into pngquant and standalone libimagequant`
			`- reduced memory usage by further 30% (and more for very large images)`
			`- less precise remapping improving speed by 25% in higher speed settings`
			`- --output option for writing converted file under the given path`
			`- light dithering with --floyd=0.5`
			`- fixed regression in dithering of alpha channel`

			`version 1.8`
			`-----------`
			`- min/max quality option (number of colors is automatically adjusted for desired quality level)`
			`- switched option parsing to getopt_long (syntax such as -s1 and --ext=ext is supported)`
			`- significantly improved performance thanks to custom partial sorting`
			`- optional Cocoa (Mac OS X) image reader for color profile support`
			`- reduced memory usage by 20%`
			`- remapping improved for very low number of colors`

			`version 1.7`
			`-----------`
			`- new, accurate RGBA color similarity algorithm`
			`- change of optional SSE3 code to SSE2 that is always enabled on x86-64`
			`- optional OpenMP-based parallelisation of remapping`
			`- changed long options to use double hyphen (-force to --force) [thanks to Jari Aalto]`

			`version 1.6`
			`-----------`
			`- novel dithering algorithm that doesn't add noise unless necessary`
			`- perceptual weighting of colors taking into account edges and noise`
			`- much faster remapping`
			`- improved portability, makefiles and man page`

			`version 1.5`
			`-----------`
			`- palettes postprocessed with Voronoi iteration`
			`- better RGBA color similarity algorithm and Floyd-Steinberg remapping`
			`- SSE optimisations`

			`version 1.4`
			`-----------`
			`- median cut is applied many times in a feedback loop`
			`- speed/quality trade-off option`
			`- faster remap of transparent areas`

			`version 1.3`
			`-----------`
			`- significant changes to the algorithm: use of variance`
			`to find largest dimensioin and to split most varying boxes`
			`- use of premultiplied alpha for color blending`
			`- conversion of output to gamma 2.2`

			`version 1.2`
			`-----------`
			`- color computation done in floating point`
			`- gamma correction applied`
			`- dropped support for very old systems & compilers`

			`version 1.1`
			`-----------`
			`- alpha-sensitive color reduction and dithering`
			`- support -- and - arguments in command line`
			`- number of colors optional (defaults to 256)`
			`- increased maximum number of colors in histogram`

			`version 1.0`
			`-----------`
			`- cleaned up Makefile.unx (better gcc optimizations, "clean" target)`
			`- recompiled binaries with zlib 1.1.4`

			`version 0.95`
			`------------`
			`- fixed Win32 filter bug (binary mode for stdin/stdout)`
			`- fixed cosmetic "choosing colors" verbosity buglet`
			`- fixed palette-size bug when number of colors in image < number requested`
			`- fixed sample-depth bug (png_set_packing() not retroactively smart)`

			`version 0.91`
			`------------`
			`- fixed some verbose/non-verbose oopers`
			`- fixed Win32 (MSVC) portability issues (getpid(), random(), srandom())`
			`- added Makefile.w32 for MSVC (tested with 5.0)`

			`version 0.90`
			`------------`
			`- added support for multiple files on command line`
			`- changed stdin support to write PNG stream to stdout (not "stdin-fs8.png")`

			`version 0.75`
			`------------`
			`- added support for any type of input file [Glenn Randers-Pehrson]`
			`- fixed palette-(re)scaling bug`
			`- added -verbose and -quiet options (default now is -quiet)`
			`- added palette-remapping to minimize size of tRNS chunk`
			`- made Floyd-Steinberg dithering default`
			`- changed output naming scheme to -fs8.png and -or8.png (FS or ordered dither)`

			`version 0.70`
			`------------`
			`- first public release`