I have just upgraded to FFmpeg 7.1.1 on Windows. The help file for the hevc_qsv encoder lists the new qualifier qsv_params, which is supposed to pass encoding parameter’s directly to the codec.
The documentation at ffmpeg.org also describes this. Several web sites also mention it, but all of them, and the documentation, only give a theoretical example, such as this in the help message:
“Set QSV encoder parameters as key1=value1:key2=value2:…”
and this in the ffmpeg documentation:
ffmpeg -i input.mp4 -c:v h264_qsv -qsv_params "CodingOption1=1:CodingOption2=2" output.mp4
So I took a working procedure in a batch file and changed:
-rdo 1
To:
-qsv_params "rdo=1"
And I get the error message:
[hevc_qsv @ 0000029637b182c0] Failed to set parameter: rdo
I’m sure the rdo parameter exists, I have been using it for years and it’s in the help page and ffmpeg documentation. The command procedure works fine with -rdo 1 as a separate parameter.
I have also tried -qsv_params "preset=veryslow:global_quality=28" and it’s also rejected
Has anyone actually used qsv_paramters successfully, and can you give an example that has been tested and works?
I know it’s not urgent, but if there is a new feature that doesn’t work, it’s important in the long run to document and correct it.
