Nvidia h264_nvenc doesn't accept rgb0 input in 18.04

[bmegli]

Same workflow works in 20.04

[bmegli]

ffmpeg -encoders | grep h264

 V..... libx264              libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (codec h264)
 V..... libx264rgb           libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 RGB (codec h264)
 V..... h264_nvenc           NVIDIA NVENC H.264 encoder (codec h264)
 V..... h264_omx             OpenMAX IL H.264 video encoder (codec h264)
 V..... h264_v4l2m2m         V4L2 mem2mem H.264 encoder wrapper (codec h264)
 V..... h264_vaapi           H.264/AVC (VAAPI) (codec h264)
 V..... nvenc                NVIDIA NVENC H.264 encoder (codec h264)
 V..... nvenc_h264           NVIDIA NVENC H.264 encoder (codec h264)

ffmpeg -h encoder=h264_nvenc

Encoder h264_nvenc [NVIDIA NVENC H.264 encoder]:
    General capabilities: delay 
    Threading capabilities: none
    Supported pixel formats: yuv420p nv12 p010le yuv444p yuv444p16le bgr0 rgb0 cuda

# other options follow

So in theory it should support bgr0 input.

Maybe it depends on context

• like working with 4:4:4 chroma subsampling
• but same workflow works well in 20.04

[bmegli]

Workarounds

• upload data in nv12
• switch to Ubuntu 20.04 or newer

[bmegli]

Possibly related:

• pixel format not correctly determined for cuda (NVENC/NVDEC) #39

So maybe it was already fixed, needs retesting