[FFmpeg-devel] [PATCH v2 35/36] vaapi_encode_h265: Set level based on stream if not set by user

[Xiang, Haihao]

On Fri, 2018-06-08 at 00:43 +0100, Mark Thompson wrote:
> Sets the level based on the stream properties if it is not explicitly
> set by the user.  Also add a tier option to set general_tier_flag, since
> that affects the level choice.
> ---
>  doc/encoders.texi              |  4 ++++
>  libavcodec/vaapi_encode_h265.c | 34 +++++++++++++++++++++++++++++++---
>  2 files changed, 35 insertions(+), 3 deletions(-)
> 
> diff --git a/doc/encoders.texi b/doc/encoders.texi
> index ceddfdda64..d61a1cc4bc 100644
> --- a/doc/encoders.texi
> +++ b/doc/encoders.texi
> @@ -2659,6 +2659,10 @@ Include recovery points where appropriate
> (@emph{recovery_point} messages).
>  @item aud
>  Include access unit delimiters in the stream (not included by default).
>  
> + at item tier
> +Set @emph{general_tier_flag}.  This may affect the level chosen for the
> stream
> +if it is not explicitly specified.
> +
>  @end table
>  
>  @item mjpeg_vaapi
> diff --git a/libavcodec/vaapi_encode_h265.c b/libavcodec/vaapi_encode_h265.c
> index 2cee19be68..100f8338d7 100644
> --- a/libavcodec/vaapi_encode_h265.c
> +++ b/libavcodec/vaapi_encode_h265.c
> @@ -30,6 +30,7 @@
>  #include "avcodec.h"
>  #include "cbs.h"
>  #include "cbs_h265.h"
> +#include "h265_profile_level.h"
>  #include "hevc.h"
>  #include "hevc_sei.h"
>  #include "internal.h"
> @@ -48,6 +49,7 @@ typedef struct VAAPIEncodeH265Context {
>      int qp;
>      int aud;
>      int profile;
> +    int tier;
>      int level;
>      int sei;
>  
> @@ -315,7 +317,7 @@ static int
> vaapi_encode_h265_init_sequence_params(AVCodecContext *avctx)
>      ptl->general_profile_space = 0;
>      ptl->general_profile_space = 0;
>      ptl->general_profile_idc   = avctx->profile;
> -    ptl->general_tier_flag     = 0;
> +    ptl->general_tier_flag     = priv->tier;
>  
>      if (chroma_format == 1) {
>          ptl->general_profile_compatibility_flag[1] = bit_depth ==  8;
> @@ -340,7 +342,25 @@ static int
> vaapi_encode_h265_init_sequence_params(AVCodecContext *avctx)
>  
>      ptl->general_lower_bit_rate_constraint_flag = 1;
>  
> -    ptl->general_level_idc = avctx->level;
> +    if (avctx->level != FF_LEVEL_UNKNOWN) {
> +        ptl->general_level_idc = avctx->level;

Fist check whether the level idc is legal? User may set a level which can not 
be found in h265_levels. 

> +    } else {
> +        const H265LevelDescriptor *level;
> +
> +        level = ff_h265_guess_level(ptl, avctx->bit_rate,
> +                                    ctx->surface_width, ctx->surface_height,
> +                                    1, 1, 1, (ctx->b_per_p > 0) + 1);
> +        if (level) {
> +            av_log(avctx, AV_LOG_VERBOSE, "Using level %s.\n", level->name);
> +            ptl->general_level_idc = level->level_idc;
> +        } else {
> +            av_log(avctx, AV_LOG_VERBOSE, "Stream will not conform to "
> +                   "any normal level; using level 8.5.\n");
> +            ptl->general_level_idc = 255;
> +            // The tier flag must be set in level 8.5.
> +            ptl->general_tier_flag = 1;
> +        }
> +    }
>  
>      vps->vps_sub_layer_ordering_info_present_flag = 0;
>      vps->vps_max_dec_pic_buffering_minus1[0]      = (ctx->b_per_p > 0) + 1;
> @@ -1146,9 +1166,17 @@ static const AVOption vaapi_encode_h265_options[] = {
>      { PROFILE("rext",               FF_PROFILE_HEVC_REXT) },
>  #undef PROFILE
>  
> +    { "tier", "Set tier (general_tier_flag)",
> +      OFFSET(tier), AV_OPT_TYPE_INT,
> +      { .i64 = 0 }, 0, 1, FLAGS, "tier" },
> +    { "main", NULL, 0, AV_OPT_TYPE_CONST,
> +      { .i64 = 0 }, 0, 0, FLAGS, "tier" },
> +    { "high", NULL, 0, AV_OPT_TYPE_CONST,
> +      { .i64 = 1 }, 0, 0, FLAGS, "tier" },
> +
>      { "level", "Set level (general_level_idc)",
>        OFFSET(level), AV_OPT_TYPE_INT,
> -      { .i64 = 153 }, 0x00, 0xff, FLAGS, "level" },
> +      { .i64 = FF_LEVEL_UNKNOWN }, FF_LEVEL_UNKNOWN, 0xff, FLAGS, "level" },
>  
>  #define LEVEL(name, value) name, NULL, 0, AV_OPT_TYPE_CONST, \
>        { .i64 = value }, 0, 0, FLAGS, "level"