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I am following a tutorial on how to work with cinelerra-cv, in the very beginning it was said, that the very first step in working with cinelerra, is to convert whatever video clip one has into the dnxhd format. It was just said, not explained how to do it.

After some research, I came across ffmpeg, but I have no idea how to use it with regard to dnxhd, with the little knowledge I gathered about ffmpeg, my guess how to do it would be:

ffmpeg -i <video-clip> -vcodec dnxhd <video-clip-in-dnxhd>

however, this does not work, and the examples I have seen on converting into dnxhd with ffmpeg I do not understand, they seemed each time having some different tags without explaining why to use them.

  • 1
    deb-indus.org/tuto/ffmpeg-howto.htm#Encoding_VC-3 would suggest ffmpeg -i <input_file> -vcodec dnxhd -b <bitrate> -an output.mov – Rinzwind Apr 21 '17 at 13:44
  • thanks, I ve seen this one before and I was like: Do I have to specify a bitrate and does it have to have no sound (-an)? ....i mean can one only work in cinelerra with dnxhd videoclips which have no sound? – sharkant Apr 21 '17 at 13:50
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    -b <int> : Set video bitrate in bit/s ( default = 200k ). so I would assume you must add a bitrate since 200k is not a valid option. But the -an I would drop :) – Rinzwind Apr 21 '17 at 13:59
  • does the bitrate depend on the source file or the file into which one wants to convert? ....i mean if i just try using 200 could it work? – sharkant Apr 21 '17 at 14:03
  • No. You need to specify the bitrate for this particular encoder. – llogan Apr 21 '17 at 19:22
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This is a picky encoder so you have to choose proper parameters including:

  • frame rate
  • pixel format / color space
  • width x height / resolution / frame size
  • bitrate

See the Valid DNxHD parameters below for accepted values.


DNxHD example

This example will scale to 1280x720, choose a frame rate of 30000/1001 (aka "29.97"), and a pixel format of YUV 4:2:2 planar.

ffmpeg -i input -c:v dnxhd -vf "scale=1280:720,fps=30000/1001,format=yuv422p" -b:v 110M -c:a pcm_s16le output.mov
  • If your input file already conforms to some of the accepted parameters then you don't have to manually declare them.

  • Output format container for DNxHD is typically MXF or MOV.


DNxHR example

DNxHR is for resolutions bigger than 1080p such as 2K, 4K, and 8K.

Example for DNxHR HQX, 10-bit 4:2:2, 4K (4096x2160), 24 fps:

ffmpeg -i input -c:v dnxhd -vf "scale=4096:2160,fps=24,format=yuv422p10le" -profile:v dnxhr_hqx -b:v 746M -c:a pcm_s16le output.mov

The -profile:v output option is required to select the DNxHR profile, such as -profile:v dnxhr_hq.

Accepted values for -profile:v are: dnxhd, dnxhr_444, dnxhr_hqx, dnxhr_hq, dnxhr_sq, dnxhr_lb.

  • DNxHR LB: dnxhr_lb - Low Bandwidth. 8-bit 4:2:2 (yuv422p). Offline Quality.
  • DNxHR SQ: dnxhr_sq - Standard Quality. 8-bit 4:2:2 (yuv422p). Suitable for delivery format.
  • DNxHR HQ: dnxhr_hq - High Quality. 8-bit 4:2:2 (yuv422p).
  • DNxHR HQX: dnxhr_hqx - High Quality. 10-bit 4:2:2 (yuv422p10le). UHD/4K Broadcast-quality delivery.
  • DNxHR 444: dnxhr_444 - Finishing Quality. 10-bit 4:4:4 (yuv444p10le). Cinema-quality delivery.

The above list was adapted from DNxHR codec.


Valid DNxHD parameters

ffmpeg will fail if you provide incorrect values, but it can provide a list of what is accepted. (For DNxHR, scroll down to Valid DNxHR parameters section below.)

You can show the list with the following "dummy" command:

$ ffmpeg -loglevel error -f lavfi -i testsrc2 -c:v dnxhd -f null -
Frame size: 1920x1080p; bitrate: 175Mbps; pixel format: yuv422p10
Frame size: 1920x1080p; bitrate: 185Mbps; pixel format: yuv422p10
Frame size: 1920x1080p; bitrate: 365Mbps; pixel format: yuv422p10
Frame size: 1920x1080p; bitrate: 440Mbps; pixel format: yuv422p10
Frame size: 1920x1080p; bitrate: 115Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 120Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 145Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 240Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 290Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 175Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 185Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 220Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 365Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 440Mbps; pixel format: yuv422p
Frame size: 1920x1080i; bitrate: 185Mbps; pixel format: yuv422p10
Frame size: 1920x1080i; bitrate: 220Mbps; pixel format: yuv422p10
Frame size: 1920x1080i; bitrate: 120Mbps; pixel format: yuv422p
Frame size: 1920x1080i; bitrate: 145Mbps; pixel format: yuv422p
Frame size: 1920x1080i; bitrate: 185Mbps; pixel format: yuv422p
Frame size: 1920x1080i; bitrate: 220Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 120Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 145Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 90Mbps; pixel format: yuv422p10
Frame size: 1280x720p; bitrate: 180Mbps; pixel format: yuv422p10
Frame size: 1280x720p; bitrate: 220Mbps; pixel format: yuv422p10
Frame size: 1280x720p; bitrate: 90Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 110Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 180Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 220Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 60Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 75Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 120Mbps; pixel format: yuv422p
Frame size: 1280x720p; bitrate: 145Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 36Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 45Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 75Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 90Mbps; pixel format: yuv422p
Frame size: 1920x1080p; bitrate: 350Mbps; pixel format: yuv444p10, gbrp10
Frame size: 1920x1080p; bitrate: 390Mbps; pixel format: yuv444p10, gbrp10
Frame size: 1920x1080p; bitrate: 440Mbps; pixel format: yuv444p10, gbrp10
Frame size: 1920x1080p; bitrate: 730Mbps; pixel format: yuv444p10, gbrp10
Frame size: 1920x1080p; bitrate: 880Mbps; pixel format: yuv444p10, gbrp10
Frame size: 960x720p; bitrate: 42Mbps; pixel format: yuv422p
Frame size: 960x720p; bitrate: 60Mbps; pixel format: yuv422p
Frame size: 960x720p; bitrate: 75Mbps; pixel format: yuv422p
Frame size: 960x720p; bitrate: 115Mbps; pixel format: yuv422p
Frame size: 1440x1080p; bitrate: 63Mbps; pixel format: yuv422p
Frame size: 1440x1080p; bitrate: 84Mbps; pixel format: yuv422p
Frame size: 1440x1080p; bitrate: 100Mbps; pixel format: yuv422p
Frame size: 1440x1080p; bitrate: 110Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 80Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 90Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 100Mbps; pixel format: yuv422p
Frame size: 1440x1080i; bitrate: 110Mbps; pixel format: yuv422p

Valid DNxHR parameters

See pages 111-112 of Avid High-Resolution Workflows Guide.


Important Notes about Frame Rate

  • Frame rate is missing from the list that is generated from this command. ffmpeg will blindly accept any frame rate for this encoder, and Avid software will reportedly accept it (unconfirmed), but the DNxHD bitrate is supposed to be matched to specific frame rates only. For maximum compatibility I recommended only using the proper bitrate/frame rate combination. So use the command above to get the proper bitrates and pixel formats accepted by ffmpeg, and cross reference with the List of Avid DNxHD resolutions or the DNxHD White Paper (page 9) for the proper frame rates.

  • The frame rates listed in the links above are using inaccurate rounded approximations. The proper values are listed below; the incorrect alias is to the left and the proper value is to the right.

     Wrong     Correct  
     29.97     30000/1001
     59.94     60000/1001
     23.967    24000/1001
    

    So instead of fps=29.97 use fps=30000/1001, or instead of -r 29.97 use -r 30000/1001.


More options

For additional encoder specific options, and a list of supported pixel formats, refer to:

ffmpeg -h encoder=dnxhd

Alpha / transparency

The FFmpeg DNxHD/DNxHR encoder does not support alpha.


Errors

ff_frame_thread_encoder_init failed
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Conversion failed!

This means that your frame rate, width, height, pixel format, and/or bitrate are incorrect. Refer to Valid DNxHD parameters above for accepted values.

pixel format is incompatible with DNxHD profile

Choose a proper pixel format using the format filter. See the DNxHD example above.

| improve this answer | |
  • I don't understand. why does this work : ffmpeg -i input.mkv -c:v dnxhd -vf "scale=1280:720,fps=60000/1001,format=yuv422p" -b:v 110M -c:a pcm_s16le output.mov but this doesn't : ffmpeg -i input.mkv -c:v dnxhd -vf "scale=1920:1080,fps=60000/1001,format=yuv422p" -b:v 110M -c:a pcm_s16le output.mov?? Not putting the scale argument doesn't work. not putting fps doesn't either. I have 1080p 60fps footage. I'm not interested in scaling it down or reducing the framerate I just want to shove it into davinci resolve's mouth so I can edit and upload to youtube and get on with my life. – tatsu Jul 29 at 20:58
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    ok so increasing the bitrate to 185M (-b:v 185M) did the trick. this might help people – tatsu Jul 29 at 21:06
  • so a shorter version of the command is this : ffmpeg -i input.mkv -c:v dnxhd -b:v 185M -c:a pcm_s16le output.mov – tatsu Jul 29 at 21:11
  • 1
    @tatsu Good to see you figured it out. It's a picky format, so it will only accept certain combinations. The example in the answer is a "worse case scenario" just to show how to change the resolution, fps, pixel format, and bitrate. I should add some simpler examples. – llogan Aug 1 at 19:18

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