[FFmpeg-devel] [PATCH, v2] lavc/vaapi_encode: add support for AVC Trellis
Fu, Linjie
linjie.fu at intel.com
Thu Jun 13 05:02:33 EEST 2019
> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Mark Thompson
> Sent: Thursday, June 13, 2019 06:37
> To: ffmpeg-devel at ffmpeg.org
> Subject: Re: [FFmpeg-devel] [PATCH, v2] lavc/vaapi_encode: add support for
> AVC Trellis
>
> On 12/06/2019 16:28, Linjie Fu wrote:
> > Add support for VAAPI AVC Trellis Quantization with limitation:
> > - VA-API version >= (1, 0, 0)
> >
> > Use option "-trellis off/I/P/B" to disable or enable Trellis
> > quantization for I/P/B frames.
> >
> > Signed-off-by: Linjie Fu <linjie.fu at intel.com>
> > ---
> > [v2]: Since nonstandard struct for VAEncMiscParameterQuantization is
> > fixed: https://github.com/intel/libva/issues/265
>
> Should the version check be for the first release this fix is in rather than for
> libva 2.0, then?
I've been thinking about the concerns before, too.
Since the nonstandard structure is supported more robustly, uint32_t data[]
in misc now can be point to the uint64_t quantization and make this feature
valid.
The remaining concern is that using a uint32_t pointer to point a uint64_t one (should be uint32_t) which
is not functional.
So I choose to check the version libva 2.0 which supported Trellis for the first time to support
more libva version.
Will update the version check to libva 2.5 to eliminate all concerns if it's more acceptable.
>
> > update patch based on:
> >
> http://git.ffmpeg.org/gitweb/ffmpeg.git/commit/2880a32c668023bfee47450
> 95c885450d547ae45
> > libavcodec/vaapi_encode.c | 48
> ++++++++++++++++++++++++++++++++++
> > libavcodec/vaapi_encode.h | 9 +++++--
> > libavcodec/vaapi_encode_h264.c | 9 +++++++
> > 3 files changed, 64 insertions(+), 2 deletions(-)
> >
> > diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c
> > index dd2a24de04..fbfbe78c6b 100644
> > --- a/libavcodec/vaapi_encode.c
> > +++ b/libavcodec/vaapi_encode.c
> > @@ -1671,6 +1671,48 @@ rc_mode_found:
> > return 0;
> > }
> >
> > +static av_cold int vaapi_encode_init_quantization(AVCodecContext
> *avctx)
> > +{
> > +#if VA_CHECK_VERSION(1, 0, 0)
> > + VAAPIEncodeContext *ctx = avctx->priv_data;
> > + VAStatus vas;
> > + VAConfigAttrib attr = { VAConfigAttribEncQuantization };
> > + int trellis = ctx->trellis;
>
> This variable isn't really doing anything.
Yep, trying to match the behavior with quality but since this variable is not frequently
used, ctx->trellis seems to be enough.
>
> > +
> > + vas = vaGetConfigAttributes(ctx->hwctx->display,
> > + ctx->va_profile,
> > + ctx->va_entrypoint,
> > + &attr, 1);
> > + if (vas != VA_STATUS_SUCCESS) {
> > + av_log(avctx, AV_LOG_ERROR, "Failed to query quantization "
> > + "config attribute: %d (%s).\n", vas, vaErrorStr(vas));
> > + return AVERROR_EXTERNAL;
> > + }
> > +
> > + if (attr.value == VA_ATTRIB_NOT_SUPPORTED ||
> > + attr.value == VA_ENC_QUANTIZATION_NONE) {
> > + av_log(avctx, AV_LOG_WARNING, "Special Quantization attribute is
> not "
> > + "supported: will use default quantization.\n");
> > + } else if (attr.value == VA_ENC_QUANTIZATION_TRELLIS_SUPPORTED){
> > + av_log(avctx, AV_LOG_VERBOSE, "Quantization Trellis supported.\n");
> > +
> > + ctx->quantization_params = (VAEncMiscParameterQuantization) {
> > + .quantization_flags.value = trellis,
> > + };
> > +
> > + vaapi_encode_add_global_param(avctx,
> > + VAEncMiscParameterTypeQuantization,
> > + &ctx->quantization_params,
> > + sizeof(ctx->quantization_params));
> > + }
> > +#else
> > + av_log(avctx, AV_LOG_WARNING, "The encode quantization option
> (Trellis) is "
> > + "not supported with this VAAPI version.\n");
> > +#endif
> > +
> > + return 0;
> > +}
> > +
> > static av_cold int vaapi_encode_init_gop_structure(AVCodecContext
> *avctx)
> > {
> > VAAPIEncodeContext *ctx = avctx->priv_data;
> > @@ -2132,6 +2174,12 @@ av_cold int
> ff_vaapi_encode_init(AVCodecContext *avctx)
> > if (err < 0)
> > goto fail;
> >
> > + if (ctx->trellis) {
> > + err = vaapi_encode_init_quantization(avctx);
> > + if (err < 0)
> > + goto fail;
> > + }
> > +
> > if (avctx->compression_level >= 0) {
> > err = vaapi_encode_init_quality(avctx);
> > if (err < 0)
> > diff --git a/libavcodec/vaapi_encode.h b/libavcodec/vaapi_encode.h
> > index eeec06036b..b24735da59 100644
> > --- a/libavcodec/vaapi_encode.h
> > +++ b/libavcodec/vaapi_encode.h
> > @@ -37,7 +37,7 @@ struct VAAPIEncodePicture;
> >
> > enum {
> > MAX_CONFIG_ATTRIBUTES = 4,
> > - MAX_GLOBAL_PARAMS = 4,
> > + MAX_GLOBAL_PARAMS = 5,
> > MAX_DPB_SIZE = 16,
> > MAX_PICTURE_REFERENCES = 2,
> > MAX_REORDER_DELAY = 16,
> > @@ -220,6 +220,9 @@ typedef struct VAAPIEncodeContext {
> > // Packed headers which will actually be sent.
> > unsigned int va_packed_headers;
> >
> > + // Quantization mode
> > + int trellis;
>
> Put this field further up, above the "set before calling
> ff_vaapi_encode_init()" line.
Will follow, thanks.
>
> > +
> > // Configuration attributes to use when creating va_config.
> > VAConfigAttrib config_attributes[MAX_CONFIG_ATTRIBUTES];
> > int nb_config_attributes;
> > @@ -256,7 +259,9 @@ typedef struct VAAPIEncodeContext {
> > #if VA_CHECK_VERSION(0, 36, 0)
> > VAEncMiscParameterBufferQualityLevel quality_params;
> > #endif
> > -
> > +#if VA_CHECK_VERSION(1, 0, 0)
> > + VAEncMiscParameterQuantization quantization_params;
> > +#endif
> > // Per-sequence parameter structure
> (VAEncSequenceParameterBuffer*).
> > void *codec_sequence_params;
> >
> > diff --git a/libavcodec/vaapi_encode_h264.c
> b/libavcodec/vaapi_encode_h264.c
> > index d1427112ea..427fb6320e 100644
> > --- a/libavcodec/vaapi_encode_h264.c
> > +++ b/libavcodec/vaapi_encode_h264.c
> > @@ -72,6 +72,7 @@ typedef struct VAAPIEncodeH264Context {
> > int sei;
> > int profile;
> > int level;
> > + int trellis;
> >
> > // Derived settings.
> > int mb_width;
> > @@ -1233,6 +1234,8 @@ static av_cold int
> vaapi_encode_h264_init(AVCodecContext *avctx)
> > if (priv->qp > 0)
> > ctx->explicit_qp = priv->qp;
> >
> > + ctx->trellis = priv->trellis;
> > +
> > return ff_vaapi_encode_init(avctx);
> > }
> >
> > @@ -1263,6 +1266,12 @@ static const AVOption
> vaapi_encode_h264_options[] = {
> > { "cabac", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN,
> INT_MAX, FLAGS, "coder" },
> > { "vlc", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN,
> INT_MAX, FLAGS, "coder" },
> > { "ac", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN,
> INT_MAX, FLAGS, "coder" },
> > + { "trellis", "Trellis Quantization",
> > + OFFSET(trellis), AV_OPT_TYPE_FLAGS, { .i64 = 0}, 0, INT_MAX, FLAGS,
> "trellis"},
> > + { "off", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN,
> INT_MAX, FLAGS, "trellis"},
> > + { "I", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN,
> INT_MAX, FLAGS, "trellis"},
> > + { "P", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 4 }, INT_MIN,
> INT_MAX, FLAGS, "trellis"},
> > + { "B", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 8 }, INT_MIN,
> INT_MAX, FLAGS, "trellis"},
> >
> > { "aud", "Include AUD",
> > OFFSET(aud), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
> >
>
> Can you add a bit more explanation about what the option does and when
> someone might want to set it? (Ideally in a documentation patch...)
Yes, will add docs as Jun has advised, too.
> I don't think it should be specific to H.264, either - the technique can apply in
> any codec feeding sets of block coefficients into an entropy coder. The check
> above does the right thing for any driver which doesn't support it for a given
> codec.
Trellis is not supported in HEVC currently:
https://github.com/intel/media-driver/issues/574
That's one of the reasons to keep it private for AVC.
However since the query/check is available , it would be better to take it as a
common option for all codec.
Thanks a lot,
- Linjie
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