[vlc-devel] problem trying to use vda acceleration on a mac - VDA requires extradata.

[Rafaël Carré]

Le 06/08/2013 18:10, Peter Martin a écrit :
> Hi,
> 
> I'm testing both the latest 2.1 nightly and 2.2 nightly on a mac and I 
> have started seeing this message when run with --avcodec-hw=vda:
> 
> [0x7fdc738348b0] avcodec decoder debug: available hardware decoder 
> output format 61 (dxva2_vld)
> [0x7fdc738348b0] avcodec decoder debug: available hardware decoder 
> output format 53 (vaapi_vld)
> [0x7fdc738348b0] avcodec decoder debug: available hardware decoder 
> output format 81 (vda_vld)
> [0x7fdc738348b0] avcodec decoder debug: available software decoder 
> output format 0 (yuv420p)
> [0x7fdc7217cae0] main generic debug: looking for hw decoder module 
> matching "vda": 1 candidates
> [0x7fdc7217cae0] vda generic debug: opening VDA module
> [0x7fdc7217cae0] vda generic warning: VDA requires extradata.
> [0x7fdc7217cae0] main generic debug: no hw decoder modules matched
> 
> This is using a multicast udp transport stream with an hd bbc feed which 
> is an h.264 1080i stream
> 
> This happens on several versions including those from 5th August and 
> building from source using the 2.1.git and trunk vlc.git.
> 
> Is this a known problem or maybe a regression?
> Have I missed something important?
> Has vda ever actually worked?
> 
> I do recall, but can't nail the date down when the vda module complained 
> about not enough extradata - I think it fund 6 but expected 7. Sorry I 
> don't have any notes on this.

Just a wild guess: could be 3 bytes start code versus 4 bytes start code
expected by the module.