[FFmpeg-devel] [PATCH v2 1/4] lavc/vaapi_encode_h265: Add P frame to GPB frame support for hevc_vaapi
Mark Thompson
sw at jkqxz.net
Mon Feb 21 14:06:36 EET 2022
On 21/02/2022 02:13, Fei Wang wrote:
> From: Linjie Fu <linjie.fu at intel.com>
>
> Use GPB frames to replace regular P frames if backend driver does not
> support it.
>
> - GPB:
> Generalized P and B picture. P frames replaced by B frames with
> forward-predict only, L0 == L1. Normal B frames still have 2
> different ref_lists and allow bi-prediction
>
> Signed-off-by: Linjie Fu <linjie.fu at intel.com>
> Signed-off-by: Fei Wang <fei.w.wang at intel.com>
> ---
> libavcodec/vaapi_encode.c | 33 +++++++++++++++++++++++++++++++--
> libavcodec/vaapi_encode.h | 1 +
> libavcodec/vaapi_encode_h265.c | 15 +++++++++++++++
> 3 files changed, 47 insertions(+), 2 deletions(-)
This always fails immediately on current iHD (7e357b4bea76b2fe2522e6af41ae02ea69cec49e):
$ ./ffmpeg_g -v 44 -y -hwaccel vaapi -hwaccel_output_format vaapi -i in.mp4 -an -c:v hevc_vaapi -low_power 1 out.mp4
...
[hevc_vaapi @ 0x560e81d45e80] Using input frames context (format vaapi) with hevc_vaapi encoder.
[hevc_vaapi @ 0x560e81d45e80] Input surface format is nv12.
[hevc_vaapi @ 0x560e81d45e80] Using VAAPI profile VAProfileHEVCMain (17).
[hevc_vaapi @ 0x560e81d45e80] Using VAAPI entrypoint VAEntrypointEncSliceLP (8).
[hevc_vaapi @ 0x560e81d45e80] Using VAAPI render target format YUV420 (0x1).
[hevc_vaapi @ 0x560e81d45e80] Using CTU size 64x64, min CB size 8x8.
[hevc_vaapi @ 0x560e81d45e80] No quality level set; using default (25).
[hevc_vaapi @ 0x560e81d45e80] RC mode: CQP.
[hevc_vaapi @ 0x560e81d45e80] RC quality: 25.
[hevc_vaapi @ 0x560e81d45e80] RC framerate: 30000/1001 (29.97 fps).
[hevc_vaapi @ 0x560e81d45e80] Use GPB B frames to replace regular P frames.
[hevc_vaapi @ 0x560e81d45e80] Using intra, GPB-B-frames and B-frames (supported references: 3 / 3).
[hevc_vaapi @ 0x560e81d45e80] All wanted packed headers available (wanted 0xd, found 0x1f).
[hevc_vaapi @ 0x560e81d45e80] Using level 4.
...
[hevc_vaapi @ 0x560e81d45e80] Failed to end picture encode issue: 24 (internal encoding error).
[hevc_vaapi @ 0x560e81d45e80] Encode failed: -5.
Video encoding failed
...
$ cat /proc/cpuinfo | grep 'model name' | head -1
model name : Intel(R) Core(TM) i7-1065G7 CPU @ 1.30GHz
$ uname -v
#1 SMP PREEMPT Debian 5.16.7-2 (2022-02-09)
Do you get this too, or is your setup different somehow?
> diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
> index 3bf379b1a0..95eca7c288 100644
> --- a/libavcodec/vaapi_encode.c
> +++ b/libavcodec/vaapi_encode.c
> @@ -1845,6 +1845,30 @@ static av_cold int vaapi_encode_init_gop_structure(AVCodecContext *avctx)
> ref_l1 = attr.value >> 16 & 0xffff;
> }
>
> + ctx->p_to_gpb = 0;
> +
> +#if VA_CHECK_VERSION(1, 9, 0)
> + attr = (VAConfigAttrib) { VAConfigAttribPredictionDirection };
> + vas = vaGetConfigAttributes(ctx->hwctx->display,
> + ctx->va_profile,
> + ctx->va_entrypoint,
> + &attr, 1);
This probably shouldn't be done at all if the user has selected a codec without B-frames or a configuration which is intra-only, because the log message is confusing:
[mjpeg_vaapi @ 0x55b90d72ee00] Driver does not report whether support GPB, use regular P frames.
[mjpeg_vaapi @ 0x55b90d72ee00] Using intra frames only.
> + if (vas != VA_STATUS_SUCCESS) {
> + av_log(avctx, AV_LOG_WARNING, "Failed to query prediction direction "
> + "attribute: %d (%s).\n", vas, vaErrorStr(vas));
And fail?
> + } else if (attr.value == VA_ATTRIB_NOT_SUPPORTED) {
> + av_log(avctx, AV_LOG_VERBOSE, "Driver does not report whether "
> + "support GPB, use regular P frames.\n");
"support GPB" is a strange thing to say. It's a constraint - any driver which supports B-frames will let you have the same thing in both RefPicLists, but some require it because they don't support P-frames.
So maybe something like "Driver does not report any additional prediction constraints, using P-frames."?
> + } else {
> + if (attr.value & VA_PREDICTION_DIRECTION_BI_NOT_EMPTY) {
> + ctx->p_to_gpb = 1;
> + av_log(avctx, AV_LOG_VERBOSE, "Use GPB B frames to replace "
> + "regular P frames.\n");
Maybe "Driver does not support P-frames, replacing them with B-frames."?
> + } else
> + av_log(avctx, AV_LOG_VERBOSE, "Use regular P frames.\n");
> + }
> +#endif
> +
> if (ctx->codec->flags & FLAG_INTRA_ONLY ||
> avctx->gop_size <= 1) {
> av_log(avctx, AV_LOG_VERBOSE, "Using intra frames only.\n");
> @@ -1861,8 +1885,13 @@ static av_cold int vaapi_encode_init_gop_structure(AVCodecContext *avctx)
> ctx->p_per_i = INT_MAX;
> ctx->b_per_p = 0;
> } else {
> - av_log(avctx, AV_LOG_VERBOSE, "Using intra, P- and B-frames "
> - "(supported references: %d / %d).\n", ref_l0, ref_l1);
> + if (ctx->p_to_gpb)
> + av_log(avctx, AV_LOG_VERBOSE, "Using intra, GPB-B-frames and "
> + "B-frames (supported references: %d / %d).\n",
> + ref_l0, ref_l1);
Seems easier to just say intra and B-frames (though this isn't really adding anything to the message above - it's still effectively a P-frame referring to one previous frame, just using B-slices to do it in a strange way).
> + else
> + av_log(avctx, AV_LOG_VERBOSE, "Using intra, P- and B-frames "
> + "(supported references: %d / %d).\n", ref_l0, ref_l1);
> ctx->gop_size = avctx->gop_size;
> ctx->p_per_i = INT_MAX;
> ctx->b_per_p = avctx->max_b_frames;
> diff --git a/libavcodec/vaapi_encode.h b/libavcodec/vaapi_encode.h
> index b41604a883..61c5615eb8 100644
> --- a/libavcodec/vaapi_encode.h
> +++ b/libavcodec/vaapi_encode.h
> @@ -328,6 +328,7 @@ typedef struct VAAPIEncodeContext {
> int idr_counter;
> int gop_counter;
> int end_of_stream;
> + int p_to_gpb;
>
> // Whether the driver supports ROI at all.
> int roi_allowed;
> diff --git a/libavcodec/vaapi_encode_h265.c b/libavcodec/vaapi_encode_h265.c
> index e1dc53dfa9..ea45893508 100644
> --- a/libavcodec/vaapi_encode_h265.c
> +++ b/libavcodec/vaapi_encode_h265.c
> @@ -886,6 +886,7 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
> VAAPIEncodePicture *pic,
> VAAPIEncodeSlice *slice)
> {
> + VAAPIEncodeContext *ctx = avctx->priv_data;
> VAAPIEncodeH265Context *priv = avctx->priv_data;
> VAAPIEncodeH265Picture *hpic = pic->priv_data;
> const H265RawSPS *sps = &priv->raw_sps;
> @@ -908,6 +909,9 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
>
> sh->slice_type = hpic->slice_type;
>
> + if (sh->slice_type == HEVC_SLICE_P && ctx->p_to_gpb)
> + sh->slice_type = HEVC_SLICE_B;
> +
> sh->slice_pic_order_cnt_lsb = hpic->pic_order_cnt &
> (1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1;
>
> @@ -1066,6 +1070,9 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
> av_assert0(pic->type == PICTURE_TYPE_P ||
> pic->type == PICTURE_TYPE_B);
> vslice->ref_pic_list0[0] = vpic->reference_frames[0];
> + if (ctx->p_to_gpb && pic->type == PICTURE_TYPE_P)
> + // Reference for GPB B-frame, L0 == L1
> + vslice->ref_pic_list1[0] = vpic->reference_frames[0];
> }
> if (pic->nb_refs >= 2) {
> // Forward reference for B-frame.
> @@ -1073,6 +1080,14 @@ static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
> vslice->ref_pic_list1[0] = vpic->reference_frames[1];
> }
>
> + if (pic->type == PICTURE_TYPE_P && ctx->p_to_gpb) {
> + vslice->slice_type = HEVC_SLICE_B;
> + for (i = 0; i < FF_ARRAY_ELEMS(vslice->ref_pic_list0); i++) {
> + vslice->ref_pic_list1[i].picture_id = vslice->ref_pic_list0[i].picture_id;
> + vslice->ref_pic_list1[i].flags = vslice->ref_pic_list0[i].flags;
> + }
> + }
Is it sensible to implement this properly in the generic code rather than having special ad-hoc code here?
(Is there any chance this will also be a thing for e.g. H.264 or H.266 in future?)
> +
> return 0;
> }
>
- Mark
More information about the ffmpeg-devel
mailing list