#5874: tiff LZW compression does not compress enough ------------------------------------+----------------------------------- Reporter: jsteinkamp | Owner: Type: defect | Status: open Priority: normal | Component: avcodec Version: git-master | Resolution: Keywords: tif | Blocked By: Blocking: | Reproduced by developer: 1 Analyzed by developer: 0 | ------------------------------------+-----------------------------------
Comment (by jsteinkamp): jsteinkamp Replying to [ticket:5874 jsteinkamp]: HI, I tested this bug again. The LZW compression for TIFF is still larger than photoshop. photoshop file 716 KB, ffmpeg file 884KB The file was 32 bit 1024x768 included an alpha channel ffmpeg version: N-91024-g293a6e8332 built with gcc 7.3.0 (GCC) configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable- bzlib --e nable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable- libblur ay --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable- libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enab le-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-li bvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable- libx265 --en able-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable- libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enabl e-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enabl e-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enab le-dxva2 --enable-avisynth libavutil 56. 18.100 / 56. 18.100 libavcodec 58. 19.101 / 58. 19.101 libavformat 58. 13.102 / 58. 13.102 libavdevice 58. 4.100 / 58. 4.100 libavfilter 7. 21.100 / 7. 21.100 libswscale 5. 2.100 / 5. 2.100 libswresample 3. 2.100 / 3. 2.100 libpostproc 55. 2.100 / 55. 2.100 Input #0, tiff_pipe, from 'hibiscus1.0001.tif': Duration: N/A, bitrate: N/A Stream #0:0: Video: tiff, rgba, 1024x768 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc Stream mapping: Stream #0:0 -> #0:0 (tiff (native) -> tiff (native)) Press [q] to stop, [?] for help Output #0, image2, to 'hibiscus1.0001.tif': Metadata: encoder : Lavf58.13.102 Stream #0:0: Video: tiff, rgba, 1024x768 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s , 25 fps, 25 tbn, 25 tbc Metadata: encoder : Lavc58.19.101 tiff frame= 1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A speed=0.526x video:883kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing o verhead: unknown > Summary of the bug:tiff LZW compression might not compress enough > How to reproduce: > ffmpeg -y -i b.tif -pix_fmt rgb24 -vcodec tiff -compression_algo lzw test_24.tif > The file made in ffmepg is 59.2 MB, if I resave the file in photoshop it is 39.8 MB > ffmpeg version > N-78598-g98a0053 > Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker. -- Ticket URL: <https://trac.ffmpeg.org/ticket/5874#comment:5> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker _______________________________________________ FFmpeg-trac mailing list FFmpeg-trac@avcodec.org http://ffmpeg.org/mailman/listinfo/ffmpeg-trac