[FFmpeg-devel] [PATCH V1 1/2] lavfi/vf_scale_vaapi: add scaling mode setting support.

[Mark Thompson]

On 06/12/2018 10:39, Jun Zhao wrote:
> before this change, scale_vaapi hard coding the scaling mode, add a
> new option "mode" to setting the scaling mode, it can be use to change
> scaling algorithm for performance/quality trade off.
> 
> Signed-off-by: Jun Zhao <mypopydev at gmail.com>
> ---
>  libavfilter/vf_scale_vaapi.c |   33 ++++++++++++++++++++++++++++++---
>  1 files changed, 30 insertions(+), 3 deletions(-)
> 
> diff --git a/libavfilter/vf_scale_vaapi.c b/libavfilter/vf_scale_vaapi.c
> index d6529d5..ad222e6 100644
> --- a/libavfilter/vf_scale_vaapi.c
> +++ b/libavfilter/vf_scale_vaapi.c
> @@ -35,10 +35,26 @@ typedef struct ScaleVAAPIContext {
>  
>      char *output_format_string;
>  
> +    int   mode;
> +
>      char *w_expr;      // width expression string
>      char *h_expr;      // height expression string
>  } ScaleVAAPIContext;
>  
> +static const char *scale_vaapi_mode_name(int mode)
> +{
> +    switch (mode) {
> +#define D(name) case VA_FILTER_SCALING_ ## name: return #name
> +        D(DEFAULT);
> +        D(FAST);
> +        D(HQ);
> +#undef D
> +    default:
> +        return "Invalid";
> +    }
> +}
> +
> +
>  static int scale_vaapi_config_output(AVFilterLink *outlink)
>  {
>      AVFilterLink *inlink     = outlink->src->inputs[0];
> @@ -70,6 +86,7 @@ static int scale_vaapi_filter_frame(AVFilterLink *inlink, AVFrame *input_frame)
>      AVFilterContext *avctx   = inlink->dst;
>      AVFilterLink *outlink    = avctx->outputs[0];
>      VAAPIVPPContext *vpp_ctx = avctx->priv;
> +    ScaleVAAPIContext *ctx   = avctx->priv;
>      AVFrame *output_frame    = NULL;
>      VASurfaceID input_surface, output_surface;
>      VAProcPipelineParameterBuffer params;
> @@ -119,7 +136,7 @@ static int scale_vaapi_filter_frame(AVFilterLink *inlink, AVFrame *input_frame)
>      params.output_color_standard = params.surface_color_standard;
>  
>      params.pipeline_flags = 0;
> -    params.filter_flags = VA_FILTER_SCALING_HQ;
> +    params.filter_flags |= ctx->mode;

"=" would feel safer - "|=" implies something else might have been setting it as well.

>  
>      err = ff_vaapi_vpp_render_picture(avctx, &params, output_surface);
>      if (err < 0)
> @@ -131,9 +148,10 @@ static int scale_vaapi_filter_frame(AVFilterLink *inlink, AVFrame *input_frame)
>  
>      av_frame_free(&input_frame);
>  
> -    av_log(avctx, AV_LOG_DEBUG, "Filter output: %s, %ux%u (%"PRId64").\n",
> +    av_log(avctx, AV_LOG_DEBUG, "Filter output: %s, %ux%u (%"PRId64"), mode: %s.\n",
>             av_get_pix_fmt_name(output_frame->format),
> -           output_frame->width, output_frame->height, output_frame->pts);
> +           output_frame->width, output_frame->height, output_frame->pts,
> +           scale_vaapi_mode_name(ctx->mode));
>  
>      return ff_filter_frame(outlink, output_frame);
>  
> @@ -174,6 +192,15 @@ static const AVOption scale_vaapi_options[] = {
>        OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, .flags = FLAGS },
>      { "format", "Output video format (software format of hardware frames)",
>        OFFSET(output_format_string), AV_OPT_TYPE_STRING, .flags = FLAGS },
> +    { "mode", "Scaling mode",
> +      OFFSET(mode), AV_OPT_TYPE_INT, { .i64 = VA_FILTER_SCALING_HQ },
> +      0, VA_FILTER_SCALING_NL_ANAMORPHIC, FLAGS, "mode" },

NL_ANAMORPHIC mentioned in this limit but not offered as an option?

> +    { "default", "Use the default (depend on the driver) scaling algorithm",
> +      0, AV_OPT_TYPE_CONST, { .i64 = VA_FILTER_SCALING_DEFAULT }, 0, 0, FLAGS, "mode" },
> +    { "fast", "Use fast scaling algorithm",
> +      0, AV_OPT_TYPE_CONST, { .i64 = VA_FILTER_SCALING_FAST }, 0, 0, FLAGS, "mode" },
> +    { "hq", "Use high quality scaling algorithm",
> +      0, AV_OPT_TYPE_CONST, { .i64 = VA_FILTER_SCALING_HQ }, 0, 0, FLAGS,  "mode" },
>      { NULL },
>  };
>  
> 

LGTM in any case.

(Ack on keeping the HQ default - IIRC the reason for choosing HQ as the mode when this was written was that the default/fast mode was not faster and had much worse quality on some of the older Intel platforms (I would guess Bay Trail based on what I probably had available at the time).  Might be worth investigating further if you have such machines available to test.)

Thanks,

- Mark