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

[Mark Thompson]

On 15/06/18 05:22, Xiang, Haihao wrote:
> 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/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. 

The user should be able to specify an arbitrary value explicitly.  As for H.264 I'll add a check that this fits in the 8-bit field, though.

>> +    } 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"

Thanks,

- Mark