[FFmpeg-devel] [PATCH V3] libavcodec/qsvenc: add low latency P-pyramid support for qsv

[wenbin.chen at intel.com]

From: Wenbinc-Bin <wenbin.chen at intel.com>

Add low latency P-pyramid support for qsv, and it relates to a new
command line parameter "-p_strategy". To enable this flag, user also
need to set "-bf" to 0.
P-strategy has two modes "simple" and "pyramid". The details of these
model refers to https://github.com/Intel-Media-SDK/MediaSDK/blob/master/doc/mediasdk-man.md#PRefType

Signed-off-by Wenbin Chen <wenbin.chen at intel.com>
---
 libavcodec/qsvenc.c | 32 ++++++++++++++++++++++++++++++++
 libavcodec/qsvenc.h |  2 ++
 2 files changed, 34 insertions(+)

diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index 2bd2a56227..3b75a83432 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -268,6 +268,15 @@ static void dump_video_param(AVCodecContext *avctx, QSVEncContext *q,
     case MFX_B_REF_PYRAMID: av_log(avctx, AV_LOG_VERBOSE, "pyramid");   break;
     default:                av_log(avctx, AV_LOG_VERBOSE, "auto");      break;
     }
+
+    av_log(avctx, AV_LOG_VERBOSE, "; PRefType: ");
+    switch(co3->PRefType){
+    case MFX_P_REF_DEFAULT: av_log(avctx, AV_LOG_VERBOSE, "default");   break;
+    case MFX_P_REF_SIMPLE:  av_log(avctx, AV_LOG_VERBOSE, "simple");    break;
+    case MFX_P_REF_PYRAMID: av_log(avctx, AV_LOG_VERBOSE, "pyramid");   break;
+    default:                av_log(avctx, AV_LOG_VERBOSE, "unknown");   break;
+    }
+
     av_log(avctx, AV_LOG_VERBOSE, "\n");
 #endif
 
@@ -777,6 +786,29 @@ FF_ENABLE_DEPRECATION_WARNINGS
 #if QSV_HAVE_CO3
         q->extco3.Header.BufferId      = MFX_EXTBUFF_CODING_OPTION3;
         q->extco3.Header.BufferSz      = sizeof(q->extco3);
+
+        switch(q->p_strategy){
+        case 0:
+            q->extco3.PRefType = MFX_P_REF_DEFAULT;
+            break;
+        case 1:
+            q->extco3.PRefType = MFX_P_REF_SIMPLE;
+            break;
+        case 2:
+            q->extco3.PRefType = MFX_P_REF_PYRAMID;
+            break;
+        default:
+            q->extco3.PRefType = MFX_P_REF_DEFAULT;
+            av_log(avctx, AV_LOG_WARNING, "invalid p_strategy, set to default\n");
+            break;
+        } 
+        if((q->extco3.PRefType == MFX_P_REF_SIMPLE ||
+            q->extco3.PRefType == MFX_P_REF_PYRAMID) && 
+            avctx->max_b_frames != 0){
+            av_log(avctx, AV_LOG_WARNING, "Please set max_b_frames(-bf) to 0 to enable P-pyramid\n");
+        }
+
+
 #if QSV_HAVE_GPB
         if (avctx->codec_id == AV_CODEC_ID_HEVC)
             q->extco3.GPB              = q->gpb ? MFX_CODINGOPTION_ON : MFX_CODINGOPTION_OFF;
diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h
index 6d305f87dd..1b6149cccf 100644
--- a/libavcodec/qsvenc.h
+++ b/libavcodec/qsvenc.h
@@ -95,6 +95,7 @@
 { "adaptive_i",     "Adaptive I-frame placement",             OFFSET(qsv.adaptive_i),     AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE },                         \
 { "adaptive_b",     "Adaptive B-frame placement",             OFFSET(qsv.adaptive_b),     AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE },                         \
 { "b_strategy",     "Strategy to choose between I/P/B-frames", OFFSET(qsv.b_strategy),    AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE },                         \
+{ "p_strategy",     "enable P-pyramid 0-default 1-simple 2-pyramid",    OFFSET(qsv.p_strategy), AV_OPT_TYPE_INT,    { .i64 = 0}, 0,    2, VE },                         \
 { "forced_idr",     "Forcing I frames as IDR frames",         OFFSET(qsv.forced_idr),     AV_OPT_TYPE_BOOL,{ .i64 = 0  },  0,          1, VE },                         \
 { "low_power", "enable low power mode(experimental: many limitations by mfx version, BRC modes, etc.)", OFFSET(qsv.low_power), AV_OPT_TYPE_BOOL, { .i64 = 0}, 0, 1, VE},\
 
@@ -181,6 +182,7 @@ typedef struct QSVEncContext {
     int extbrc;
     int adaptive_i;
     int adaptive_b;
+    int p_strategy;
     int b_strategy;
     int cavlc;
 
-- 
2.25.1