[FFmpeg-user] Convert images to DNXHD 444

[Gonzalo Garramuño]

El 10/04/18 a las 07:37, Carl Eugen Hoyos escribió:
> 2018-04-09 23:08 GMT+02:00, Wayne Poll <WPoll at nhnz.tv>:
>
>> It is possible but the 440 profile isn't valid for 23.98fps material - you
>> should be using DNxHD 350x for 10-bit 4:4:4 RGB @ 23.98fps. The DNxHD 440
>> (8-bit) and DNxHD 440x (10-bit) are only valid at higher frame rates, such
>> as 29.97p, 59.94p and 60p
> How can I reproduce this?
$ ffmpeg -i explosion_FG_040_persp.%04d.exr -r 24000/1001 -codec:v dnxhd 
-profile:v dnxhd -bit_rate 120Mbps -pix_fmt yuv422p10 -bit_rate 90Mbps 
-y test.mov

ffmpeg version N-90206-g8aa3007 Copyright (c) 2000-2018 the FFmpeg 
developers
   built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.9) 20160609
   configuration: --enable-gpl --enable-shared --enable-gray 
--enable-runtime-cpudetect --enable-bzlib --enable-libfreetype 
--enable-libmp3lame --enable-libtheora --enable-libvorbis 
--enable-libass --enable-libvpx --enable-libx264 --enable-libx265
   libavutil      56.  7.101 / 56.  7.101
   libavcodec     58. 13.100 / 58. 13.100
   libavformat    58. 10.100 / 58. 10.100
   libavdevice    58.  2.100 / 58.  2.100
   libavfilter     7. 12.100 /  7. 12.100
   libswscale      5.  0.101 /  5.  0.101
   libswresample   3.  0.101 /  3.  0.101
   libpostproc    55.  0.100 / 55.  0.100
Input #0, image2, from 'explosion_FG_040_persp.%04d.exr':
   Duration: 00:00:02.84, start: 0.000000, bitrate: N/A
     Stream #0:0: Video: exr, rgb48le, 1280x720 [SAR 1:1 DAR 16:9], 25 
tbr, 25 tbn, 25 tbc
Stream mapping:
   Stream #0:0 -> #0:0 (exr (native) -> dnxhd (native))
Press [q] to stop, [?] for help

[dnxhd @ 0x2183c40] video parameters incompatible with DNxHD. Valid 
DNxHD profiles:
[dnxhd @ 0x2183c40] Frame size: 1920x1080p; bit_depth=10; bitrate: 
175Mbps; pixel format: yuv422p10
...etc...
[dnxhd @ 0x2183c40] Frame size: 1280x720p; bit_depth=10; bitrate: 
90Mbps; pixel format: yuv422p10
...etc...

Assuming a resolution of 1280x720, the video parameters are okay, but 
the bit rate gets passed as 200000 always and that makes the check for 
resolution and yuv not run.  I modified the code to print the bit rate 
and that's how I found out.  I am hunting where the avctx->bit_rate gets 
set to 200000.  Maybe you can help, Carl?

-- 
Gonzalo Garramuño