[FFmpeg-user] 4K 60Hz Directshow Video Capture

[Andy Furniss]

Alex P wrote:
> Hi James,
> 
> ffmpeg -f dshow -video_size 3840x2160 -framerate 60000/1001 -rtbufsize 2100000000 -pixel_format bgr24 -i video="MZ0380 PCI, Analog 01 Capture" -c:v h264_nvenc -preset lossless -f null -
> Gives me the same error

Maybe it doesn't do rgb24 lossless - you should paste full output of 
ffmpeg and not top post on this list.

> ffmpeg -f dshow -video_size 3840x2160 -framerate 60000/1001 -rtbufsize 2100000000 -pixel_format bgr24 -i video="MZ0380 PCI, Analog 01 Capture" -c:v rawvideo -f null -
> Gets me nearly x1 performance when executing from a ram disk but
> 
> ffmpeg -f dshow -video_size 3840x2160 -framerate 60000/1001 -rtbufsize 2100000000 -pixel_format bgr24 -i video="MZ0380 PCI, Analog 01 Capture" -c:v rawvideo raw.nut
> Only gets me x0.5 and the buffer overflows.

The device that raw.nut is written to would need to take 1.5 
gigabytes/sec to get full speed.