[vlc-devel] [PATCH] [RFC] decoder: add more decoder device types

Steve Lhomme robux4 at ycbcr.xyz
Mon Jun 24 08:47:48 CEST 2019


On 2019-06-24 7:31, Steve Lhomme wrote:
> These are types needed to move the decoder pools that exist in various display
> modules closer to the decoder.
> 
> That means we need to make the decision early on which flavor of OpenGL will be
> used before the OpenGL display module is created. Depending on the platform
> used it could be VAAPI, VDPAU, DXVA2, OpenGL PBO (persistent and non-persistent).
> 
> And to do that we need to create the "decoder device" using the es_format_t
> that will be decoded (so we can pick a hardware decoder or a software one),
> which contains the codec, profile and dimensions. When any of these change we
> will need to create a new decoder device (or check the one we have is
> compatible).

That would be the fmt_in of the decoder, whearas right now we only get 
the fmt_out.video in the display module. This is quite a stretch from 
what we have now.

In the case of the hardware decoder pick we don't really need it. In 
automatic mode we can already pick the best candidate. If it doesn't 
work we fallback to software decoding. On Windows it's not an issue, we 
don't do a zero copy rendering in that case.

In OpenGL (not automatically select on Windows) it's trickier as the 
fallback to software decoding can still use zero copy as done in 
converter_sw.c. The pool that is created there should be moved to the 
decoder. To do that we need the same vlc_gl_t that is used by the 
display module. But if DXVA2 (or VAAPI or VDPAU on other platforms) was 
"best picked" we don't have this information.

We need a way to retry to create the decoder device (and display module) 
if the selected decoder device didn't work.

> ---
>   include/vlc_codec.h | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/include/vlc_codec.h b/include/vlc_codec.h
> index 71f3e8439f..ec5d7e32af 100644
> --- a/include/vlc_codec.h
> +++ b/include/vlc_codec.h
> @@ -491,6 +491,9 @@ enum vlc_decoder_device_type
>       VLC_DECODER_DEVICE_DXVA2,
>       VLC_DECODER_DEVICE_D3D11VA,
>       VLC_DECODER_DEVICE_AWINDOW,
> +    VLC_DECODER_DEVICE_VULKAN,
> +    VLC_DECODER_DEVICE_PBO,
> +    VLC_DECODER_DEVICE_MMAL,
>   };
>   
>   /**
> @@ -514,6 +517,12 @@ typedef struct vlc_decoder_device
>        * The type of pointer will depend of the type:
>        * VAAPI: VADisplay
>        * VDPAU: vdp_t *
> +     * DXVA2: IDirect3DDevice9*
> +     * D3D11VA: ID3D11DeviceContext*
> +     * AWindow: android AWindowHandler*
> +     * Vulkan: vlc_vk_t*
> +     * OpenGL PBO: vlc_gl_t*
> +     * MMAL: MMAL_PORT_T*
>        */
>       void *opaque;
>   } vlc_decoder_device;
> -- 
> 2.17.1
> 
> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel
> 


More information about the vlc-devel mailing list