[FFmpeg-user] Can I get hardware decode of WMV with qsv encode?

[Li, Zhong]

> From: ffmpeg-user [mailto:ffmpeg-user-bounces at ffmpeg.org] On Behalf Of
> Jason Coleman
> Sent: Thursday, July 19, 2018 2:54 AM
> To: ffmpeg-user at ffmpeg.org
> Subject: [FFmpeg-user] Can I get hardware decode of WMV with qsv
> encode?
> 
> Hello,
> 
> 
> I'm trying to figure out if I can use the QuickSync support to handle WMV
> files. QuickSync itself I believe can handle WMV, but I don't see a codec
> option I can invoke that appears to designate WMV decode using the qsv
> engine.

VC1 video codec is supported. Please try: "-hwaccel qsv -c:v vc1_qsv" is the WMV files have vc1 video clips.
 
> 
> If I can't use qsv directly to handle wmv3, is it possible for me to specify
> dxva2 for the decode(presumable using QuickSync via DirectX) part, but then
> have QuickSync handle the transform(resize) and encode stages? I think
> dxva2 would be fine for the transform as well, I don't think it will work on
> the encode stage for qsv based h.264/h.265, but if I'm wrong there, that's
> fine.  The goal here is to offload as much of my transcode operation as
> possible when transcoding from a wmv2/3 source to an h.264 or hevc
> target.
> 
> 
> Thank you!

You may want to try: ffmpeg -hwaccel dxva2 -hwaccel_output_format dxva2_vld -i input.mp4 -vf 'hwmap=derive_device=qsv,format=qsv' -c:v h264_qsv output.mp4
(Haven't verified this due to I don't care Windows very much)