[FFmpeg-user] zimg colorspace yuv -> rgb possible?

[Andy Furniss]

Andy Furniss wrote:
Here's the assert - after seeing swscale in the first test I tried 
format=rgb24 ...

ffmpeg -loglevel debug -i snk-422i-flags.y4m -vf zscale,format=rgb24 
zimg-422.png
ffmpeg version N-78059-g2e31434 Copyright (c) 2000-2016 the FFmpeg 
developers
   built with gcc 5.3.0 (GCC)
   configuration: --prefix=/usr --disable-doc --enable-gpl 
--enable-libzimg --enable-libvpx --enable-libx265 --enable-libdcadec 
--enable-libmp3lame --enable-libx264
   libavutil      55. 15.100 / 55. 15.100
   libavcodec     57. 22.101 / 57. 22.101
   libavformat    57. 23.100 / 57. 23.100
   libavdevice    57.  0.100 / 57.  0.100
   libavfilter     6. 27.100 /  6. 27.100
   libswscale      4.  0.100 /  4.  0.100
   libswresample   2.  0.101 /  2.  0.101
   libpostproc    54.  0.100 / 54.  0.100
Splitting the commandline.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging 
level) with argument 'debug'.
Reading option '-i' ... matched as input file with argument 
'snk-422i-flags.y4m'.
Reading option '-vf' ... matched as option 'vf' (set video filters) with 
argument 'zscale,format=rgb24'.
Reading option 'zimg-422.png' ... matched as output file.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option loglevel (set logging level) with argument debug.
Successfully parsed a group of options.
Parsing a group of options: input file snk-422i-flags.y4m.
Successfully parsed a group of options.
Opening an input file: snk-422i-flags.y4m.
[yuv4mpegpipe @ 0x1fec0a0] Format yuv4mpegpipe probed with size=2048 and 
score=100
[yuv4mpegpipe @ 0x1fec0a0] Before avformat_find_stream_info() pos: 52 
bytes read:32768 seeks:0
[yuv4mpegpipe @ 0x1fec0a0] All info found
[yuv4mpegpipe @ 0x1fec0a0] After avformat_find_stream_info() pos: 829498 
bytes read:829498 seeks:0 frames:1
Input #0, yuv4mpegpipe, from 'snk-422i-flags.y4m':
   Duration: 00:00:00.04, start: 0.000000, bitrate: 165899 kb/s
     Stream #0:0, 1, 1/25: Video: rawvideo, 1 reference frame (Y42B / 
0x42323459), yuv422p, 720x576, 1/25, SAR 64:45 DAR 16:9, 25 fps, 25 tbr, 
25 tbn, 25 tbc
Successfully opened the file.
Parsing a group of options: output file zimg-422.png.
Applying option vf (set video filters) with argument zscale,format=rgb24.
Successfully parsed a group of options.
Opening an output file: zimg-422.png.
Successfully opened the file.
detected 4 logical cores
[Parsed_format_1 @ 0x1ff3ec0] compat: called with args=[rgb24]
[Parsed_format_1 @ 0x1ff3ec0] Setting 'pix_fmts' to value 'rgb24'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'video_size' to 
value '720x576'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'pix_fmt' to value '4'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'time_base' to value 
'1/25'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'pixel_aspect' to 
value '64/45'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'sws_param' to value 
'flags=2'
[graph 0 input from stream 0:0 @ 0x1ff3d40] Setting 'frame_rate' to 
value '25/1'
[graph 0 input from stream 0:0 @ 0x1ff3d40] w:720 h:576 pixfmt:yuv422p 
tb:1/25 fr:25/1 sar:64/45 sws_param:flags=2
[format @ 0x1ff4720] compat: called with 
args=[rgb24|rgba|rgb48be|rgba64be|pal8|gray|ya8|gray16be|ya16be|monob]
[format @ 0x1ff4720] Setting 'pix_fmts' to value 
'rgb24|rgba|rgb48be|rgba64be|pal8|gray|ya8|gray16be|ya16be|monob'
[auto-inserted scaler 0 @ 0x1ffdfc0] Setting 'flags' to value 'bicubic'
[auto-inserted scaler 0 @ 0x1ffdfc0] w:iw h:ih flags:'bicubic' interl:0
[Parsed_format_1 @ 0x1ff3ec0] auto-inserting filter 'auto-inserted 
scaler 0' between the filter 'Parsed_zscale_0' and the filter 
'Parsed_format_1'
[AVFilterGraph @ 0x1ff2d40] query_formats: 5 queried, 3 merged, 1 
already done, 0 delayed
[Parsed_zscale_0 @ 0x1ff3720] w:720 h:576 fmt:yuv422p sar:64/45 -> w:720 
h:576 fmt:yuv422p sar:64/45
[auto-inserted scaler 0 @ 0x1ffdfc0] w:720 h:576 fmt:yuv422p sar:64/45 
-> w:720 h:576 fmt:rgb24 sar:64/45 flags:0x4
Output #0, image2, to 'zimg-422.png':
   Metadata:
     encoder         : Lavf57.23.100
     Stream #0:0, 0, 1/25: Video: png, 1 reference frame, rgb24, 720x576 
[SAR 64:45 DAR 16:9], 1/25, q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
     Metadata:
       encoder         : Lavc57.22.101 png
Stream mapping:
   Stream #0:0 -> #0:0 (rawvideo (native) -> png (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per 
stream)
[Parsed_zscale_0 @ 0x1ff3720] w:720 h:576 fmt:yuv422p sar:64/45 -> w:720 
h:576 fmt:yuv422p sar:64/45
ffmpeg: src/zimg/api/zimg.cpp:485: zimg_error_code_e 
zimg_filter_graph_process(const zimg_filter_graph*, const 
zimg_image_buffer_const*, const zimg_image_buffer*, void*, 
zimg_filter_graph_callback, void*, zimg_filter_graph_callback, void*): 
Assertion `(!(src->plane[0].data) || 
reinterpret_cast<uintptr_t>(src->plane[0].data) % zimg::ALIGNMENT == 0) 
&& ("pointer not aligned")' failed.