[FFmpeg-devel] [PATCH,v4] lavc/qsvenc: add VDENC support for H264

[Linjie Fu]

Add VDENC(lowpower mode) support for QSV H264

It's an experimental function(like lowpower in vaapi) with
some limitations:
- CBR/VBR require HuC which should be explicitly loaded via i915
module parameter(i915.enable_guc=2 for linux kernel version >= 4.16)

Use option "-low_power 1" to enable VDENC.
Add in dump_video_param() to show the status of VDENC in runtime log.

Signed-off-by: Linjie Fu <linjie.fu at intel.com>
---
[v2]: modified the commit message and option comments, use AV_OPT_TYPE_BOOL
to replace AV_OPT_TYPE_INT.
[v3]: enable H264 VDENC separately.
[v4]: Add in dump_video_param to show the status of VDENC in runtime
log.

 libavcodec/qsvenc.c      | 11 +++++++++++
 libavcodec/qsvenc.h      |  2 ++
 libavcodec/qsvenc_h264.c |  3 +++
 3 files changed, 16 insertions(+)

diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index 948751daf4..42804e68af 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -226,6 +226,14 @@ static void dump_video_param(AVCodecContext *avctx, QSVEncContext *q,
     av_log(avctx, AV_LOG_VERBOSE, "\n");
 #endif
 
+#if QSV_HAVE_VDENC
+    av_log(avctx, AV_LOG_VERBOSE, "VDENC: ");
+    if (info->LowPower == MFX_CODINGOPTION_ON)
+        av_log(avctx, AV_LOG_VERBOSE, "ON\n");
+    else
+        av_log(avctx, AV_LOG_VERBOSE, "OFF\n");
+#endif
+
 #if QSV_VERSION_ATLEAST(1, 8)
     av_log(avctx, AV_LOG_VERBOSE,
            "RepeatPPS: %s; NumMbPerSlice: %"PRIu16"; LookAheadDS: ",
@@ -464,6 +472,9 @@ static int init_video_param(AVCodecContext *avctx, QSVEncContext *q)
         }
     }
 
+#if QSV_HAVE_VDENC
+    q->param.mfx.LowPower           = q->low_power ? MFX_CODINGOPTION_ON:MFX_CODINGOPTION_OFF;
+#endif
     q->param.mfx.CodecProfile       = q->profile;
     q->param.mfx.TargetUsage        = avctx->compression_level;
     q->param.mfx.GopPicSize         = FFMAX(0, avctx->gop_size);
diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h
index 50cc4267e7..a396aa7d3f 100644
--- a/libavcodec/qsvenc.h
+++ b/libavcodec/qsvenc.h
@@ -44,6 +44,7 @@
 #define QSV_HAVE_LA     QSV_VERSION_ATLEAST(1, 7)
 #define QSV_HAVE_LA_DS  QSV_VERSION_ATLEAST(1, 8)
 #define QSV_HAVE_LA_HRD QSV_VERSION_ATLEAST(1, 11)
+#define QSV_HAVE_VDENC  QSV_VERSION_ATLEAST(1, 15)
 
 #if defined(_WIN32) || defined(__CYGWIN__)
 #define QSV_HAVE_AVBR   QSV_VERSION_ATLEAST(1, 3)
@@ -162,6 +163,7 @@ typedef struct QSVEncContext {
     int recovery_point_sei;
 
     int a53_cc;
+    int low_power;
 
 #if QSV_HAVE_MF
     int mfmode;
diff --git a/libavcodec/qsvenc_h264.c b/libavcodec/qsvenc_h264.c
index 07c9d64e6b..40071d805a 100644
--- a/libavcodec/qsvenc_h264.c
+++ b/libavcodec/qsvenc_h264.c
@@ -153,6 +153,9 @@ static const AVOption options[] = {
     { "off"    , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = MFX_MF_DISABLED }, INT_MIN, INT_MAX,     VE, "mfmode" },
     { "auto"   , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = MFX_MF_AUTO     }, INT_MIN, INT_MAX,     VE, "mfmode" },
 #endif
+#if QSV_HAVE_VDENC
+    { "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},
+#endif
 
     { NULL },
 };
-- 
2.17.1