[FFmpeg-trac] #1280(avfilter:open): Loss of alpha with yadif filter (bgra->yuv420 conv inserted instead of bgra->yuva444p) (was: Loss of alpha with yadif filter (bgra->yuv420 conv inserted instead of bgra->yuva420p))

[FFmpeg]

#1280: Loss of alpha with yadif filter (bgra->yuv420 conv inserted instead of
bgra->yuva444p)
------------------------------------+------------------------------------
             Reporter:  ronag       |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  avfilter
              Version:  git-master  |               Resolution:
             Keywords:  lavfi       |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |
------------------------------------+------------------------------------
Changes (by cehoyos):

 * status:  new => open
 * version:  unspecified => git-master
 * component:  undetermined => avfilter
 * reproduced:  0 => 1


Comment:

 I suspect this is also related to ticket #1080 (which is why -vf
 format=yuva444p,yadif without -pix_fmt is not sufficient).
 {{{
 $ ffmpeg -loop 1 -i out.png -vcodec qtrle -vf yadif=1:-1 -pix_fmt rgba
 -vframes 1 out.mov
 ffmpeg version N-40448-g16b9156 Copyright (c) 2000-2012 the FFmpeg
 developers
   built on May  7 2012 10:12:51 with gcc 4.3.2
   configuration: --cc=/usr/local/gcc-4.3.2/bin/gcc --enable-gpl --enable-
 libspeex --enable-libopenjpeg --extra-ldflags=-lm --enable-libmp3lame
 --enable-libvpx --enable-libxavs --enable-libtheora --enable-libvorbis
   libavutil      51. 49.100 / 51. 49.100
   libavcodec     54. 19.100 / 54. 19.100
   libavformat    54.  4.100 / 54.  4.100
   libavdevice    53.  4.100 / 53.  4.100
   libavfilter     2. 72.104 /  2. 72.104
   libswscale      2.  1.100 /  2.  1.100
   libswresample   0. 11.100 /  0. 11.100
   libpostproc    52.  0.100 / 52.  0.100
 Input #0, image2, from 'out.png':
   Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
     Stream #0:0: Video: png, rgba, 720x576, 25 fps, 25 tbr, 25 tbn, 25 tbc
 Incompatible pixel format 'rgba' for codec 'qtrle', auto-selecting format
 'argb'
 [buffer @ 0x8ff5960] w:720 h:576 pixfmt:rgba tb:1/1000000 sar:0/1
 sws_param:flags=2
 [yadif @ 0x8fee0e0] mode:1 parity:-1 auto_enable:0
 [buffersink @ 0x8fedc60] auto-inserting filter 'auto-inserted scale 0'
 between the filter 'Parsed_yadif_0' and the filter 'out'
 [yadif @ 0x8fee0e0] auto-inserting filter 'auto-inserted scale 1' between
 the filter 'src' and the filter 'Parsed_yadif_0'
 [scale @ 0x8fee000] w:720 h:576 fmt:rgba sar:0/1 -> w:720 h:576
 fmt:yuv420p sar:0/1 flags:0x4
 [swscaler @ 0x90442e0] No accelerated colorspace conversion found from
 yuv420p to argb.
 [swscaler @ 0x904cd80] No accelerated colorspace conversion found from
 yuv420p to argb.
 [swscaler @ 0x9055820] No accelerated colorspace conversion found from
 yuv420p to argb.
 [scale @ 0x8fee8a0] w:720 h:576 fmt:yuv420p sar:0/1 -> w:720 h:576
 fmt:argb sar:0/1 flags:0x4
 Output #0, mov, to 'out.mov':
   Metadata:
     encoder         : Lavf54.4.100
     Stream #0:0: Video: qtrle (rle  / 0x20656C72), argb, 720x576, q=2-31,
 200 kb/s, 25 tbn, 25 tbc
 Stream mapping:
   Stream #0:0 -> #0:0 (png -> qtrle)
 Press [q] to stop, [?] for help
 frame=    1 fps=0.0 q=0.0 Lsize=     952kB time=00:00:00.04
 bitrate=195027.4kbits/s dup=0 drop=1
 video:952kB audio:0kB global headers:0kB muxing overhead 0.073377%
 }}}
 Workaround is to use -vf format=yuva444p,yadif=1:-1 (and -pix_fmt).

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1280#comment:4>
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