[FFmpeg-devel] [PATCH V2] doc/encoders.texi: Add doc for qsv

Wenbin Chen wenbin.chen at intel.com
Thu Jan 6 05:00:40 EET 2022


Add doc for qsv decoder.
Add more option's introduction to qsv encoder.

Signed-off-by: Wenbin Chen <wenbin.chen at intel.com>
---
 doc/decoders.texi |  42 ++++++++
 doc/encoders.texi | 253 +++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 292 insertions(+), 3 deletions(-)

diff --git a/doc/decoders.texi b/doc/decoders.texi
index 49ab735dce..de2429abba 100644
--- a/doc/decoders.texi
+++ b/doc/decoders.texi
@@ -126,6 +126,48 @@ Set amount of frame threads to use during decoding. The default value is 0 (auto
 
 @end table
 
+ at section QSV Decoders
+
+The family of Intel QuickSync Video decoders (VC1, MPEG-2, H.264, HEVC,
+JPEG/MJPEG, VP8, VP9, AV1).
+
+ at subsection Common Options
+
+The following options are supported by all qsv decoders.
+
+ at table @option
+
+ at item @var{async_depth}
+Internal parallelization depth, the higher the value the higher the latency.
+
+ at item @var{gpu_copy}
+A GPU-accelerated copy between video and system memory
+ at table @samp
+ at item default
+ at item on
+ at item off
+ at end table
+
+ at end table
+
+ at subsection HEVC Options
+Extra options for hevc_qsv.
+
+ at table @option
+
+ at item @var{load_plugin}
+A user plugin to load in an internal session
+ at table @samp
+ at item none
+ at item hevc_sw
+ at item hevc_hw
+ at end table
+
+ at item @var{load_plugins}
+A :-separate list of hexadecimal plugin UIDs to load in an internal session
+
+ at end table
+
 @c man end VIDEO DECODERS
 
 @chapter Audio Decoders
diff --git a/doc/encoders.texi b/doc/encoders.texi
index e3b61de5a1..7cc8be1209 100644
--- a/doc/encoders.texi
+++ b/doc/encoders.texi
@@ -3123,12 +3123,13 @@ Setting a higher @option{bits_per_mb} limit will improve the speed.
 For the fastest encoding speed set the @option{qscale} parameter (4 is the
 recommended value) and do not set a size constraint.
 
- at section QSV encoders
+ at section QSV Encoders
 
-The family of Intel QuickSync Video encoders (MPEG-2, H.264, HEVC, JPEG/MJPEG and VP9)
+The family of Intel QuickSync Video encoders (MPEG-2, H.264, HEVC, JPEG/MJPEG
+and VP9)
 
+ at subsection Ratecontrol Method
 The ratecontrol method is selected as follows:
-
 @itemize @bullet
 @item
 When @option{global_quality} is specified, a quality-based mode is used.
@@ -3176,6 +3177,7 @@ Note that depending on your system, a different mode than the one you specified
 may be selected by the encoder. Set the verbosity level to @var{verbose} or
 higher to see the actual settings used by the QSV runtime.
 
+ at subsection Global Options -> MSDK Options
 Additional libavcodec global options are mapped to MSDK options as follows:
 
 @itemize
@@ -3212,6 +3214,251 @@ encoder use CAVLC instead of CABAC.
 
 @end itemize
 
+ at subsection Common Options
+Following options are used by all qsv encoders.
+
+ at table @option
+ at item @var{async_depth}
+Specifies how many asynchronous operations an application performs
+before the application explicitly synchronizes the result. If zero,
+the value is not specified.
+
+ at item @var{avbr_accuracy}
+Accuracy of the AVBR ratecontrol (unit of tenth of percent).
+
+ at item @var{avbr_convergence}
+Convergence of the AVBR ratecontrol (unit of 100 frames)
+
+The parameters @var{avbr_accuracy} and @var{avbr_convergence} are for the
+average variable bitrate control (AVBR) algorithm.
+The algorithm focuses on overall encoding quality while meeting the specified
+bitrate, @var{target_bitrate}, within the accuracy range @var{avbr_accuracy},
+after a @var{avbr_Convergence} period. This method does not follow HRD and the
+instant bitrate is not capped or padded.
+
+ at item @var{preset}
+This option itemizes a range of choices from veryfast (best speed) to veryslow
+(best quality).
+ at table @samp
+ at item veryfast
+ at item faster
+ at item fast
+ at item medium
+ at item slow
+ at item slower
+ at item veryslow
+ at end table
+
+ at item @var{forced_idr}
+Forcing I frames as IDR frames.
+
+ at item @var{low_power}
+For encoders set this flag to ON to reduce power consumption and GPU usage.
+ at end table
+
+ at subsection H264 options
+These options are used by h264_qsv
+
+ at table @option
+ at item @var{extbrc}
+Extended bitrate control.
+
+ at item @var{recovery_point_sei}
+Set this flag to insert the recovery point SEI message at the beginning of every
+intra refresh cycle.
+
+ at item @var{rdo}
+Enable rate distortion optimization.
+
+ at item @var{max_frame_size}
+Maximum encoded frame size in bytes.
+
+ at item @var{max_slice_size}
+Maximum encoded slice size in bytes.
+
+ at item @var{bitrate_limit}
+Toggle bitrate limitations.
+Modifies bitrate to be in the range imposed by the QSV encoder. Setting this
+flag off may lead to violation of HRD conformance. Mind that specifying bitrate
+below the QSV encoder range might significantly affect quality. If on this
+option takes effect in non CQP modes: if bitrate is not in the range imposed
+by the QSV encoder, it will be changed to be in the range.
+
+ at item @var{mbbrc}
+Setting this flag enables macroblock level bitrate control that generally
+improves subjective visual quality. Enabling this flag may have negative impact
+on performance and objective visual quality metric.
+
+ at item @var{adaptive_i}
+This flag controls insertion of I frames by the QSV encoder. Turn ON this flag
+to allow changing of frame type from P and B to I.
+
+ at item @var{adaptive_b}
+This flag controls changing of frame type from B to P.
+
+ at item @var{b_strategy}
+This option controls usage of B frames as reference.
+
+ at item @var{cavlc}
+If set, CAVLC is used; if unset, CABAC is used for encoding.
+
+ at item @var{vcm}
+Video conferencing mode, please see ratecontrol method.
+
+ at item @var{idr_interval}
+Distance (in I-frames) between IDR frames.
+
+ at item @var{pic_timing_sei}
+Insert picture timing SEI with pic_struct_syntax element.
+
+ at item @var{single_sei_nal_unit}
+Put all the SEI messages into one NALU.
+
+ at item @var{max_dec_frame_buffering}
+Maximum number of frames buffered in the DPB.
+
+ at item @var{look_ahead}
+Use VBR algorithm with look ahead.
+
+ at item @var{look_ahead_depth}
+Depth of look ahead in number frames.
+
+ at item @var{look_ahead_downsampling}
+Downscaling factor for the frames saved for the lookahead analysis.
+ at table @samp
+ at item unknown
+ at item auto
+ at item off
+ at item 2x
+ at item 4x
+ at end table
+
+ at item @var{int_ref_type}
+Specifies intra refresh type. The major goal of intra refresh is improvement of
+error resilience without significant impact on encoded bitstream size caused by
+I frames. The SDK encoder achieves this by encoding part of each frame in
+refresh cycle using intra MBs. @var{none} means no refresh. @var{vertical} means
+vertical refresh, by column of MBs.
+
+ at item @var{int_ref_cycle_size}
+Specifies number of pictures within refresh cycle starting from 2. 0 and 1 are
+invalid values.
+
+ at item @var{int_ref_qp_delta}
+Specifies QP difference for inserted intra MBs. This is signed value in
+[-51, 51] range if target encoding bit-depth for luma samples is 8 and this
+range is [-63, 63] for 10 bit-depth or [-75, 75] for 12 bit-depth respectively.
+
+ at item @var{profile}
+ at table @samp
+ at item unknown
+ at item baseline
+ at item main
+ at item high
+ at end table
+
+ at item @var{a53cc}
+Use A53 Closed Captions (if available).
+
+ at item @var{aud}
+Insert the Access Unit Delimiter NAL.
+
+ at item @var{mfmode}
+Multi-Frame Mode.
+ at table @samp
+ at item off
+ at item auto
+ at end table
+
+ at item @var{repeat_pps}
+Repeat pps for every frame.
+ at end table
+
+ at subsection HEVC Options
+These options are used by hevc_qsv
+
+ at table @option
+ at item @var{extbrc}
+Extended bitrate control.
+
+ at item @var{recovery_point_sei}
+Set this flag to insert the recovery point SEI message at the beginning of every
+intra refresh cycle.
+
+ at item @var{rdo}
+Enable rate distortion optimization.
+
+ at item @var{idr_interval}
+Distance (in I-frames) between IDR frames.
+ at table @samp
+ at item begin_only
+Output an IDR-frame only at the beginning of the stream.
+ at end table
+
+ at item @var{load_plugin}
+A user plugin to load in an internal session.
+ at table @samp
+ at item none
+ at item hevc_sw
+ at item hevc_hw
+ at end table
+
+ at item @var{load_plugins}
+A :-separate list of hexadecimal plugin UIDs to load in
+an internal session.
+
+ at item @var{look_ahead_depth}
+Depth of look ahead in number frames, available when extbrc option is enabled.
+
+ at item @var{profile}
+ at table @samp
+ at item unknown
+ at item main
+ at item main10
+ at item mainsp
+ at item rext
+ at end table
+
+ at item @var{gpb}
+1: GPB (generalized P/B frame)
+
+0: regular P frame.
+
+ at item @var{tile_cols}
+Number of columns for tiled encoding.
+
+ at item @var{tile_rows}
+Number of rows for tiled encoding.
+
+ at item @var{aud}
+Insert the Access Unit Delimiter NAL.
+ at end table
+
+ at subsection MPEG2 Options
+These options are used by mpeg2_qsv
+ at table @option
+ at item @var{profile}
+ at table @samp
+ at item unknown
+ at item simple
+ at item main
+ at item high
+ at end table
+ at end table
+
+ at subsection VP9 Options
+These options are used by vp9_qsv
+ at table @option
+ at item @var{profile}
+ at table @samp
+ at item unknown
+ at item profile0
+ at item profile1
+ at item profile2
+ at item profile3
+ at end table
+ at end table
+
 @section snow
 
 @subsection Options
-- 
2.25.1



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