[FFmpeg-trac] #2158(avfilter:new): overlay filter does not work with pal8 transparency

[FFmpeg]

#2158: overlay filter does not work with pal8 transparency
-------------------------------------+-------------------------------------
               Reporter:  cehoyos    |                  Owner:
                   Type:  defect     |                 Status:  new
               Priority:  normal     |              Component:  avfilter
                Version:  git-       |               Keywords:  overlay
  master                             |  alpha
             Blocked By:             |               Blocking:
Reproduced by developer:  0          |  Analyzed by developer:  0
-------------------------------------+-------------------------------------
 http://thread.gmane.org/gmane.comp.video.ffmpeg.user/43291
 I will attach a pal8 png sample that contains transparency, the overlay
 filter assumes an opaque image.
 {{{
 $ ffmpeg -i tests/lena.pnm -i pal8_alpha.png -filter_complex overlay
 out.png
 ffmpeg version N-49026-g96d1b7f Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Jan 19 2013 09:39:02 with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl --disable-indev=jack --enable-libx264
   libavutil      52. 15.100 / 52. 15.100
   libavcodec     54. 89.100 / 54. 89.100
   libavformat    54. 61.101 / 54. 61.101
   libavdevice    54.  3.102 / 54.  3.102
   libavfilter     3. 32.101 /  3. 32.101
   libswscale      2.  1.103 /  2.  1.103
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  2.100 / 52.  2.100
 Input #0, image2, from 'tests/lena.pnm':
   Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
     Stream #0:0: Video: ppm, rgb24, 256x256, 25 tbr, 25 tbn, 25 tbc
 Input #1, image2, from 'pal8_alpha.png':
   Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
     Stream #1:0: Video: png, pal8, 174x98, 25 tbr, 25 tbn, 25 tbc
 Output #0, image2, to 'out.png':
   Metadata:
     encoder         : Lavf54.61.101
     Stream #0:0: Video: png, rgba, 256x256, q=2-31, 200 kb/s, 90k tbn, 25
 tbc
 Stream mapping:
   Stream #0:0 (ppm) -> overlay:main
   Stream #1:0 (png) -> overlay:overlay
   overlay -> Stream #0:0 (png)
 Press [q] to stop, [?] for help
 frame=    1 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A
 video:134kB audio:0kB subtitle:0 global headers:0kB muxing overhead
 -100.016078%
 }}}
 The following works as expected:
 {{{
 $ ffmpeg -i pal8_alpha.png -pix_fmt rgba rgba_alpha.png
 $ ffmpeg -i tests/lena.pnm -i rgba_alpha.png -filter_complex overlay
 out.png
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2158>
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