[FFmpeg-devel] [PATCH] lavu: Add DRM hwcontext

[Jorge Ramirez]

On 09/01/2017 05:44 PM, LongChair . wrote:
> + * @file
> + * API-specific header for AV_HWDEVICE_TYPE_DRM.
> + *
> + * Internal frame allocation is not currently supported - all frames
> + * must be allocated by the user.  Thus AVHWFramesContext is always
> + * NULL, though this may change if support for frame allocation is
> + * added in future.
> + */
> +
> +enum {
> +    /**
> +     * The maximum number of layers/planes in a DRM frame.
> +     */
> +    AV_DRM_MAX_PLANES = 4
> +};

why this limit?

dont you have to call drmModeGetPlaneResources(fd) then use 
planes->count_planes?