[FFmpeg-devel] [PATCH] lavc/vaapi_encode_h264: add support for maxframesize

Linjie Fu linjie.fu at intel.com
Tue Apr 23 06:29:17 EEST 2019


Add support for max frame size:
    - max_frame_size (bytes) to indicate the allowed max frame size.
    - pass_num to indicate number of passes.
    - delta_qp to indicate adjust qp value.

Currently only AVC encoder can support this settings in multiple pass case.
If the frame size exceeds, the encoder will do more pak passes to adjust the
QP value to control the frame size.

Set Default num_passes to 4 (1~4), set delta_qp[4] = {1, 1, 1, 1}, use
new_qp for encoder if frame size exceeds the limitation:
    new_qp = base_qp + delta_qp[0] + delta_qp[1] + ...

ffmpeg -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -f rawvideo \
        -v verbose -s:v 352x288 -i ./input.yuv -vf format=nv12,hwupload \
        -c:v h264_vaapi -profile:v main -g 30 -bf 3 -max_frame_size 40000 \
        -pass_num 2 -delta_qp 2 -vframes 100 -y ./max_frame_size.h264

Signed-off-by: Linjie Fu <linjie.fu at intel.com>
---
 libavcodec/vaapi_encode.c      | 46 ++++++++++++++++++++++++++++++++++
 libavcodec/vaapi_encode.h      | 11 ++++++++
 libavcodec/vaapi_encode_h264.c | 15 +++++++++++
 3 files changed, 72 insertions(+)

diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
index 2dda451882..762c42ef13 100644
--- a/libavcodec/vaapi_encode.c
+++ b/libavcodec/vaapi_encode.c
@@ -236,6 +236,14 @@ static int vaapi_encode_issue(AVCodecContext *avctx,
             goto fail;
     }
 
+    if (ctx->max_frame_size) {
+        err = vaapi_encode_make_param_buffer(avctx, pic, VAEncMiscParameterBufferType,
+                                            (char*) &ctx->mfs_params.misc,
+                                            sizeof(ctx->mfs_params));
+        if (err < 0)
+            goto fail;
+    }
+
     if (pic->type == PICTURE_TYPE_IDR) {
         if (ctx->va_packed_headers & VA_ENC_PACKED_HEADER_SEQUENCE &&
             ctx->codec->write_sequence_header) {
@@ -1630,6 +1638,38 @@ rc_mode_found:
     return 0;
 }
 
+static av_cold int vaapi_encode_init_max_frame_size(AVCodecContext *avctx)
+{
+    VAAPIEncodeContext *ctx = avctx->priv_data;
+
+    uint32_t max_frame_size = ctx->max_frame_size;
+    uint8_t num_passes = ctx->pass_num;
+    uint8_t *delta_qp = av_mallocz_array(num_passes, sizeof(uint8_t));
+    int err = 0;
+    int i = 0;
+
+    if (!delta_qp) {
+        err = AVERROR(ENOMEM);
+        return err;
+    }
+    for (i = 0; i <num_passes; i++){
+        delta_qp[i] = ctx->delta_qp;
+    }
+
+
+    ctx->mfs_params.misc.type = VAEncMiscParameterTypeMultiPassFrameSize;
+    ctx->mfs_params.mfs.type = VAEncMiscParameterTypeMultiPassFrameSize;
+    ctx->mfs_params.mfs.max_frame_size = max_frame_size;
+    ctx->mfs_params.mfs.num_passes = num_passes;
+    ctx->mfs_params.mfs.delta_qp = delta_qp;
+
+    av_log(avctx, AV_LOG_VERBOSE, "Max Frame Size: %d bytes, "
+                                  "num_passes: %d, delta_qp = %d.\n",
+                                    ctx->max_frame_size, num_passes, ctx->delta_qp);
+
+    return 0;
+}
+
 static av_cold int vaapi_encode_init_gop_structure(AVCodecContext *avctx)
 {
     VAAPIEncodeContext *ctx = avctx->priv_data;
@@ -2095,6 +2135,12 @@ av_cold int ff_vaapi_encode_init(AVCodecContext *avctx)
             goto fail;
     }
 
+    if (ctx->max_frame_size) {
+        err = vaapi_encode_init_max_frame_size(avctx);
+        if (err < 0)
+            goto fail;
+    }
+
     vas = vaCreateConfig(ctx->hwctx->display,
                          ctx->va_profile, ctx->va_entrypoint,
                          ctx->config_attributes, ctx->nb_config_attributes,
diff --git a/libavcodec/vaapi_encode.h b/libavcodec/vaapi_encode.h
index 44a8db566e..557476d226 100644
--- a/libavcodec/vaapi_encode.h
+++ b/libavcodec/vaapi_encode.h
@@ -176,6 +176,13 @@ typedef struct VAAPIEncodeContext {
     // Desired B frame reference depth.
     int             desired_b_depth;
 
+    // Max Frame Size
+    int             max_frame_size;
+    // Number Of Passes
+    int             pass_num;
+    // Delta_qp For Each Pass
+    int             delta_qp;
+
     // Explicitly set RC mode (otherwise attempt to pick from
     // available modes).
     int             explicit_rc_mode;
@@ -268,6 +275,10 @@ typedef struct VAAPIEncodeContext {
     } quality_params;
 #endif
 
+    struct {
+        VAEncMiscParameterBuffer misc;
+        VAEncMiscParameterBufferMultiPassFrameSize mfs;
+    } __attribute__((packed)) mfs_params;
     // Per-sequence parameter structure (VAEncSequenceParameterBuffer*).
     void           *codec_sequence_params;
 
diff --git a/libavcodec/vaapi_encode_h264.c b/libavcodec/vaapi_encode_h264.c
index 4cf99d7c78..4d55dc2bac 100644
--- a/libavcodec/vaapi_encode_h264.c
+++ b/libavcodec/vaapi_encode_h264.c
@@ -72,6 +72,9 @@ typedef struct VAAPIEncodeH264Context {
     int sei;
     int profile;
     int level;
+    int max_frame_size;
+    int pass_num;
+    int delta_qp;
 
     // Derived settings.
     int mb_width;
@@ -1233,6 +1236,12 @@ static av_cold int vaapi_encode_h264_init(AVCodecContext *avctx)
     if (priv->qp > 0)
         ctx->explicit_qp = priv->qp;
 
+    if (priv->max_frame_size > 0) {
+        ctx->max_frame_size = priv->max_frame_size;
+        ctx->pass_num       = priv->pass_num;
+        ctx->delta_qp       = priv->delta_qp;
+    }
+
     return ff_vaapi_encode_init(avctx);
 }
 
@@ -1266,6 +1275,12 @@ static const AVOption vaapi_encode_h264_options[] = {
 
     { "aud", "Include AUD",
       OFFSET(aud), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
+    { "max_frame_size", "Maximum frame size (in bytes)",
+      OFFSET(max_frame_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
+    { "pass_num", "number of passes, every pass can have different QP, currently can support up to 4 passes",
+      OFFSET(pass_num), AV_OPT_TYPE_INT, { .i64 = 4 }, 0, 4, FLAGS },
+    { "delta_qp", "delta QP for every pass",
+      OFFSET(delta_qp), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 51, FLAGS },
 
     { "sei", "Set SEI to include",
       OFFSET(sei), AV_OPT_TYPE_FLAGS,
-- 
2.17.1



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