[Cin] HEVC hw encoding on AMD Polaris cards

[Andrew Randrianasulu]

В сообщении от Wednesday 15 May 2019 02:28:57 Phyllis Smith написал(а):
> @spitsyn.andrey
> 
> @GG how can I use custom script for proxy files creation inside
> > Cinelerra? Or use ffmpeg's scale_vaapi filter if vaapi used.
> >
> > Proxies can not be run easily by remote control or from a shell script.
> GG does not understand why you would not just use the Settings->Proxy
> Settings?   However, there is nothing special about the actual proxy files
> -- you can just create the scaled down size with an ffmpeg command line and
> give it the name which would have been generated by Cinelerra if you had
> created them that way.  For example, test.mp4 would just be
> test.proxy2-mp4.mpeg if you chose mpeg as the format file type (with mpeg
> becoming the extension) at 1/2 scale (the 1/2 scale shows as the 2 in
> "proxy2" of the new file name).  VERY IMPORTANT - you must use the ffmpeg
> binary in Cinelerra's thirdparty directory.  Example using mp4:
> 
> ./ffmpeg -i /root/media/tutorial.mp4 -s 720x540
> /root/media/tutorial.proxy2-mp4.mp4
> 
> Now when you load the tutorial.mp4 video, and then do Settings->Proxy
> Settings, the proxy file is already created and will load.
> -------------------------------------------------------------------------------------------------------------------------------------------
> We tried a couple of examples of using scale_vaapi  from the ffmpeg command
> line and it always failed for us on a Intel laptop with Broadwell graphics
> board.  For example, something like the following:
> 
> ffmpeg -hwaccel vaapi -hwaccel_output_format vaapi -i input.mp4 -vf
> 'scale_vaapi=1280:720'.. out.mp4

It seems correct line (at least for intel) include a bit more than just scale_vaapi:

https://xtechbiz.com/intel-vaapi-encoding-ubuntu-17-10/

Using the vaapi_scaler in the video filters : It is possible to use Intel’s QuickSync hardware via VAAPI for resize and scaling (when up-or downscaling the input source to a higher or lower resolution), using a filter snippet such as the one shown below: 
-vf 'format=nv12,hwupload,scale_vaapi=w=1920:h=1080'
You may specify a different resolution by changing the dimensions in =w= and :h= to suit your needs.

> 
> and another line from Cinelerra's thirdparty/ffmpeg directory
> documentation.  We also tried using a .opts file
> 
> for the import.  For example, for test.mp4, we created a test.opts
> file containing:
> 
>    video_filter=scale_vaapi=1280:720
> 
> and that gave us more error messages.
> 
> Question gg has - can you give us a good working ffmpeg command line
> using scale_vaapi (again you must
> use the ffmpeg binary in Cinelerra's thirdparty directory) so we can
> 
> see it that works for us?  Also, why rescale using vaapi instead of
> using a plugin?  Is it faster?
>