#4444: Transparency gets lost when scaling pal8 --------------------------------------+------------------------------------ Reporter: cehoyos | Owner: Type: defect | Status: new Priority: normal | Component: swscale Version: git-master | Keywords: pal8 alpha Blocked By: | Blocking: Reproduced by developer: 0 | Analyzed by developer: 0 --------------------------------------+------------------------------------ {{{ $ ffmpeg -i alpha.png -s 168x168 out.png ffmpeg version N-71320-gc4b2017 Copyright (c) 2000-2015 the FFmpeg developers built with gcc 4.7 (SUSE Linux) configuration: --enable-gpl libavutil 54. 22.100 / 54. 22.100 libavcodec 56. 34.100 / 56. 34.100 libavformat 56. 29.100 / 56. 29.100 libavdevice 56. 4.100 / 56. 4.100 libavfilter 5. 13.101 / 5. 13.101 libswscale 3. 1.101 / 3. 1.101 libswresample 1. 1.100 / 1. 1.100 libpostproc 53. 3.100 / 53. 3.100 Input #0, png_pipe, from 'alpha.png': Duration: N/A, bitrate: N/A Stream #0:0: Video: png, pal8, 21x21 [SAR 5:6 DAR 5:6], 25 tbr, 25 tbn, 25 tbc Output #0, apng, to 'out.png': Metadata: encoder : Lavf56.29.100 Stream #0:0: Video: apng, pal8, 168x168 [SAR 5:6 DAR 5:6], q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc Metadata: encoder : Lavc56.34.100 apng Stream mapping: Stream #0:0 -> #0:0 (png (native) -> apng (native)) Press [q] to stop, [?] for help [apng @ 0x36fd040] Only a single frame so saving as a normal PNG. frame= 1 fps=0.0 q=0.0 Lsize= 4kB time=00:00:00.04 bitrate= 823.4kbits/s video:3kB audio:0kB subtitle:0kB other streams:0kB global headers:1kB muxing overhead: 24.418253% }}} The output file is opaque. -- Ticket URL: <https://trac.ffmpeg.org/ticket/4444> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker