[FFmpeg-devel] [PATCH] lavc/qsvenc: update the selection of bitrate control method
Xiang, Haihao
haihao.xiang at intel.com
Thu Feb 8 09:39:36 EET 2024
From: Haihao Xiang <haihao.xiang at intel.com>
The default method is changed to CQP
Signed-off-by: Haihao Xiang <haihao.xiang at intel.com>
---
Changelog | 1 +
doc/encoders.texi | 7 +++--
libavcodec/qsvenc.c | 59 +++++++++++++++++++++++++++------------
libavcodec/qsvenc_av1.c | 2 +-
libavcodec/qsvenc_h264.c | 2 +-
libavcodec/qsvenc_hevc.c | 2 +-
libavcodec/qsvenc_mpeg2.c | 2 +-
libavcodec/qsvenc_vp9.c | 2 +-
8 files changed, 52 insertions(+), 25 deletions(-)
diff --git a/Changelog b/Changelog
index c5fb21d198..b9e4536233 100644
--- a/Changelog
+++ b/Changelog
@@ -24,6 +24,7 @@ version <next>:
- ffmpeg CLI options may now be used as -/opt <path>, which is equivalent
to -opt <contents of file <path>>
- showinfo bitstream filter
+- Change the default bitrate control method from VBR to CQP for QSV encoders.
version 6.1:
- libaribcaption decoder
diff --git a/doc/encoders.texi b/doc/encoders.texi
index c9fe6d6143..d1363c2174 100644
--- a/doc/encoders.texi
+++ b/doc/encoders.texi
@@ -3332,8 +3332,8 @@ quality range is 1 to 51, with 1 being the best quality.
@end itemize
@item
-Otherwise, a bitrate-based mode is used. For all of those, you should specify at
-least the desired average bitrate with the @option{b} option.
+Otherwise when the desired average bitrate is specified with the @option{b}
+option, a bitrate-based mode is used.
@itemize @minus
@item
@var{LA} - VBR with lookahead, when the @option{look_ahead} option is specified.
@@ -3354,6 +3354,9 @@ than the average bitrate.
@option{avbr_accuracy} and @option{avbr_convergence} are set to non-zero. This
mode is available for H264 and HEVC on Windows.
@end itemize
+
+ at item
+Otherwise the default ratecontrol method @var{CQP} is used.
@end itemize
Note that depending on your system, a different mode than the one you specified
diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index c63b72e384..8c6414f8ca 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -597,6 +597,12 @@ static int select_rc_mode(AVCodecContext *avctx, QSVEncContext *q)
else if (want_vcm) {
rc_mode = MFX_RATECONTROL_VCM;
rc_desc = "video conferencing mode (VCM)";
+
+ if (!avctx->bit_rate) {
+ av_log(avctx, AV_LOG_ERROR, "Using the %s ratecontrol method. Please "
+ "use the b option to set the desired bitrate.\n", rc_desc);
+ return AVERROR(EINVAL);
+ }
}
#endif
else if (want_la) {
@@ -606,32 +612,49 @@ static int select_rc_mode(AVCodecContext *avctx, QSVEncContext *q)
if (avctx->global_quality > 0) {
rc_mode = MFX_RATECONTROL_LA_ICQ;
rc_desc = "intelligent constant quality with lookahead (LA_ICQ)";
+ } else if (!avctx->bit_rate) {
+ av_log(avctx, AV_LOG_ERROR, "Using the %s ratecontrol method. Please "
+ "use the b option to set the desired bitrate.\n", rc_desc);
+ return AVERROR(EINVAL);
}
}
else if (avctx->global_quality > 0 && !avctx->rc_max_rate) {
rc_mode = MFX_RATECONTROL_ICQ;
rc_desc = "intelligent constant quality (ICQ)";
}
- else if (avctx->rc_max_rate == avctx->bit_rate) {
- rc_mode = MFX_RATECONTROL_CBR;
- rc_desc = "constant bitrate (CBR)";
- }
+ else if (avctx->bit_rate) {
+ if (avctx->rc_max_rate == avctx->bit_rate) {
+ rc_mode = MFX_RATECONTROL_CBR;
+ rc_desc = "constant bitrate (CBR)";
+ }
#if QSV_HAVE_AVBR
- else if (!avctx->rc_max_rate &&
- (avctx->codec_id == AV_CODEC_ID_H264 || avctx->codec_id == AV_CODEC_ID_HEVC) &&
- q->avbr_accuracy &&
- q->avbr_convergence) {
- rc_mode = MFX_RATECONTROL_AVBR;
- rc_desc = "average variable bitrate (AVBR)";
- }
+ else if (!avctx->rc_max_rate &&
+ (avctx->codec_id == AV_CODEC_ID_H264 || avctx->codec_id == AV_CODEC_ID_HEVC) &&
+ q->avbr_accuracy &&
+ q->avbr_convergence) {
+ rc_mode = MFX_RATECONTROL_AVBR;
+ rc_desc = "average variable bitrate (AVBR)";
+ }
#endif
- else if (avctx->global_quality > 0) {
- rc_mode = MFX_RATECONTROL_QVBR;
- rc_desc = "constant quality with VBR algorithm (QVBR)";
- }
- else {
- rc_mode = MFX_RATECONTROL_VBR;
- rc_desc = "variable bitrate (VBR)";
+ else if (avctx->global_quality > 0) {
+ rc_mode = MFX_RATECONTROL_QVBR;
+ rc_desc = "constant quality with VBR algorithm (QVBR)";
+ } else {
+ rc_mode = MFX_RATECONTROL_VBR;
+ rc_desc = "variable bitrate (VBR)";
+ }
+ } else {
+ rc_mode = MFX_RATECONTROL_CQP;
+ rc_desc = "constant quantization parameter (CQP)";
+ if (avctx->codec_id == AV_CODEC_ID_AV1)
+ avctx->global_quality = FF_QP2LAMBDA * 128;
+ else
+ avctx->global_quality = FF_QP2LAMBDA * 26;
+ av_log(avctx, AV_LOG_WARNING, "Using the constant quantization "
+ "parameter (CQP) by default. Please use the global_quality "
+ "option and other options for a quality-based mode or the b "
+ "option and other options for a bitrate-based mode if the "
+ "default is not the desired choice.\n");
}
q->param.mfx.RateControlMethod = rc_mode;
diff --git a/libavcodec/qsvenc_av1.c b/libavcodec/qsvenc_av1.c
index c697845d7b..c298eeb61c 100644
--- a/libavcodec/qsvenc_av1.c
+++ b/libavcodec/qsvenc_av1.c
@@ -129,7 +129,7 @@ static const AVClass class = {
};
static const FFCodecDefault qsv_enc_defaults[] = {
- { "b", "1M" },
+ { "b", "0" },
{ "g", "-1" },
{ "bf", "-1" },
{ "refs", "0" },
diff --git a/libavcodec/qsvenc_h264.c b/libavcodec/qsvenc_h264.c
index 071a9a79e9..004ed8076a 100644
--- a/libavcodec/qsvenc_h264.c
+++ b/libavcodec/qsvenc_h264.c
@@ -178,7 +178,7 @@ static const AVClass class = {
};
static const FFCodecDefault qsv_enc_defaults[] = {
- { "b", "1M" },
+ { "b", "0" },
{ "refs", "0" },
{ "g", "-1" },
{ "bf", "-1" },
diff --git a/libavcodec/qsvenc_hevc.c b/libavcodec/qsvenc_hevc.c
index c5b7ac7cc4..c94855e99a 100644
--- a/libavcodec/qsvenc_hevc.c
+++ b/libavcodec/qsvenc_hevc.c
@@ -374,7 +374,7 @@ static const AVClass class = {
};
static const FFCodecDefault qsv_enc_defaults[] = {
- { "b", "1M" },
+ { "b", "0" },
{ "refs", "0" },
{ "g", "248" },
{ "bf", "-1" },
diff --git a/libavcodec/qsvenc_mpeg2.c b/libavcodec/qsvenc_mpeg2.c
index 22f1ff7c0d..c2fb6fd8ff 100644
--- a/libavcodec/qsvenc_mpeg2.c
+++ b/libavcodec/qsvenc_mpeg2.c
@@ -82,7 +82,7 @@ static const AVClass class = {
};
static const FFCodecDefault qsv_enc_defaults[] = {
- { "b", "1M" },
+ { "b", "0" },
{ "refs", "0" },
// same as the x264 default
{ "g", "250" },
diff --git a/libavcodec/qsvenc_vp9.c b/libavcodec/qsvenc_vp9.c
index d0340ef94b..8d26ec529c 100644
--- a/libavcodec/qsvenc_vp9.c
+++ b/libavcodec/qsvenc_vp9.c
@@ -93,7 +93,7 @@ static const AVClass class = {
};
static const FFCodecDefault qsv_enc_defaults[] = {
- { "b", "1M" },
+ { "b", "0" },
{ "refs", "0" },
{ "g", "250" },
{ "trellis", "-1" },
--
2.34.1
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