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ffmpeg - Hardware transcoding using GPUs - AMD GPU

ffmpeg -i "input.mkv" -vaapi_device /dev/dri/renderD128 -vcodec hevc_vaapi -vf format='nv12|vaapi,hwupload' -map 0 -c:a copy -c:s copy -qp 23 "output.mkv"

NOTE:

-vaapi_device /dev/dri/renderD128, which is a shortcut to -init_hw_device vaapi=vaapi0:/dev/dri/renderD128 -filter_hw_device vaapi0, initializes a new hardware device of type vaapi.

-vf 'format=nv12,hwupload' creates the filtergraph and uses it to filter the stream.
- The encoders only accept input as VAAPI surfaces.
- If the input is in normal memory, it will need to be uploaded before giving the frames to the encoder; in the ffmpeg utility, the hwupload filter can be used for this.
- It will upload to a surface with the same layout as the software frame, so it may be necessary to add a format filter immediately before to get the input into the right format (hardware generally wants the nv12 layout).
- The hwupload filter also requires a device to upload to, which needs to be defined before the filter graph is created, which is done with -vaapi_device.

AMD GPUs

h264_amf
hevc_amf

Decoding

-hwaccel d3d11va

Encoding

For video resolution <= 4K

-c:v libx264
 
or
 
-c:v h264_amf

For video resolution > 4K

-c:v libx265 
 
or
 
-c:v hevc_amf

Examples

#1 - A corrupt 1920×1080 video:

ffmpeg -y -vsync 0 -i "input.mp4" -c:a copy -c:v h264_amf -pix_fmt yuv420p "output.mp4"

#2 - a 7680×3840 H.265 video with incompatible profile for VHT - a stutter playback 7260×3630 60fps 10bit video

ffmpeg -y -vsync 0 -i "input.mp4" -c:a copy -c:v hevc_amf -pix_fmt yuv420p "output.mp4"

#3 - a 7680×7680 video not hardware decoded because is H.264 encoded

ffmpeg -y -vsync 0 -i "input.mp4" -c:a copy -c:v hevc_amf -pix_fmt yuv420p "output.mp4"

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