[FFmpeg-devel] [PATCH] hwcontext_vdpau: implement av_hwdevice_get_hwframe_constraints()

Mark Thompson sw at jkqxz.net
Mon Jan 15 13:17:39 EET 2018


On 13/01/18 06:06, wm4 wrote:
> In addition, this does not allow creating frames contexts with sw_format
> for which no known transfer formats exist. In theory, we should check
> whether the chroma format (i.e. the sw_format) is supported at all by
> the vdpau driver, but checking for transfer formats has the same effect.
> 
> Note that the pre-existing code adds 1 to priv->nb_pix_fmts[i] for
> unknown reason, and some checks need to account for that to check for
> empty lists. They are not off-by-one errors.
> ---
>  libavutil/hwcontext_vdpau.c | 55 ++++++++++++++++++++++++++++++++-------------
>  1 file changed, 39 insertions(+), 16 deletions(-)
> 
> diff --git a/libavutil/hwcontext_vdpau.c b/libavutil/hwcontext_vdpau.c
> index 9b8f839647..c11c3cfdab 100644
> --- a/libavutil/hwcontext_vdpau.c
> +++ b/libavutil/hwcontext_vdpau.c
> @@ -79,11 +79,12 @@ static const VDPAUPixFmtMap pix_fmts_444[] = {
>  
>  static const struct {
>      VdpChromaType chroma_type;
> +    enum AVPixelFormat frames_sw_format;
>      const VDPAUPixFmtMap *map;
>  } vdpau_pix_fmts[] = {
> -    { VDP_CHROMA_TYPE_420, pix_fmts_420 },
> -    { VDP_CHROMA_TYPE_422, pix_fmts_422 },
> -    { VDP_CHROMA_TYPE_444, pix_fmts_444 },
> +    { VDP_CHROMA_TYPE_420, AV_PIX_FMT_YUV420P, pix_fmts_420 },
> +    { VDP_CHROMA_TYPE_422, AV_PIX_FMT_YUV422P, pix_fmts_422 },
> +    { VDP_CHROMA_TYPE_444, AV_PIX_FMT_YUV444P, pix_fmts_444 },
>  };
>  
>  static int count_pixfmts(const VDPAUPixFmtMap *map)
> @@ -170,6 +171,35 @@ static void vdpau_device_uninit(AVHWDeviceContext *ctx)
>          av_freep(&priv->pix_fmts[i]);
>  }
>  
> +static int vdpau_frames_get_constraints(AVHWDeviceContext *ctx,
> +                                        const void *hwconfig,
> +                                        AVHWFramesConstraints *constraints)
> +{
> +    VDPAUDeviceContext   *priv  = ctx->internal->priv;
> +    int nb_sw_formats = 0;
> +    int i;
> +
> +    constraints->valid_sw_formats = av_malloc_array(FF_ARRAY_ELEMS(vdpau_pix_fmts) + 1,
> +                                                    sizeof(*constraints->valid_sw_formats));
> +    if (!constraints->valid_sw_formats)
> +        return AVERROR(ENOMEM);
> +
> +    for (i = 0; i < FF_ARRAY_ELEMS(vdpau_pix_fmts); i++) {
> +        if (priv->nb_pix_fmts[i] > 1)
> +            constraints->valid_sw_formats[nb_sw_formats++] = vdpau_pix_fmts[i].frames_sw_format;
> +    }
> +    constraints->valid_sw_formats[nb_sw_formats] = AV_PIX_FMT_NONE;
> +
> +    constraints->valid_hw_formats = av_malloc_array(2, sizeof(*constraints->valid_hw_formats));
> +    if (!constraints->valid_hw_formats)
> +        return AVERROR(ENOMEM);
> +
> +    constraints->valid_hw_formats[0] = AV_PIX_FMT_VDPAU;
> +    constraints->valid_hw_formats[1] = AV_PIX_FMT_NONE;
> +
> +    return 0;
> +}
> +
>  static void vdpau_buffer_free(void *opaque, uint8_t *data)
>  {
>      AVHWFramesContext          *ctx = opaque;
> @@ -214,26 +244,18 @@ static int vdpau_frames_init(AVHWFramesContext *ctx)
>  
>      int i;
>  
> -    switch (ctx->sw_format) {
> -    case AV_PIX_FMT_YUV420P: priv->chroma_type = VDP_CHROMA_TYPE_420; break;
> -    case AV_PIX_FMT_YUV422P: priv->chroma_type = VDP_CHROMA_TYPE_422; break;
> -    case AV_PIX_FMT_YUV444P: priv->chroma_type = VDP_CHROMA_TYPE_444; break;
> -    default:
> -        av_log(ctx, AV_LOG_ERROR, "Unsupported data layout: %s\n",
> -               av_get_pix_fmt_name(ctx->sw_format));
> -        return AVERROR(ENOSYS);
> -    }
> -
>      for (i = 0; i < FF_ARRAY_ELEMS(vdpau_pix_fmts); i++) {
> -        if (vdpau_pix_fmts[i].chroma_type == priv->chroma_type) {
> +        if (vdpau_pix_fmts[i].frames_sw_format == ctx->sw_format) {
> +            priv->chroma_type = vdpau_pix_fmts[i].chroma_type;
>              priv->chroma_idx  = i;
>              priv->pix_fmts    = device_priv->pix_fmts[i];
>              priv->nb_pix_fmts = device_priv->nb_pix_fmts[i];
>              break;
>          }
>      }
> -    if (!priv->pix_fmts) {
> -        av_log(ctx, AV_LOG_ERROR, "Unsupported chroma type: %d\n", priv->chroma_type);
> +    if (priv->nb_pix_fmts < 2) {

I think keeping the (equivalent) older check of !priv->pix_fmts would look slightly clearer?

> +        av_log(ctx, AV_LOG_ERROR, "Unsupported sw format: %s\n",
> +               av_get_pix_fmt_name(ctx->sw_format));
>          return AVERROR(ENOSYS);
>      }
>  
> @@ -468,6 +490,7 @@ const HWContextType ff_hwcontext_type_vdpau = {
>  #endif
>      .device_init          = vdpau_device_init,
>      .device_uninit        = vdpau_device_uninit,
> +    .frames_get_constraints = vdpau_frames_get_constraints,
>      .frames_init          = vdpau_frames_init,
>      .frames_get_buffer    = vdpau_get_buffer,
>      .transfer_get_formats = vdpau_transfer_get_formats,
> 

LGTM in any case.

(Yeah, the nb_pix_fmts thing is very confusing.  I had to read that several times...)

- Mark


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