This document describes how to use the Scalable Video Technology for AV1 Encoder (SVT-AV1). In particular, this user guide describes how to run the sample application with the respective dynamically linked library.
This section describes how to run the sample encoder application that uses the SVT-AV1 Encoder library. It describes the input video format, the command line input parameters and the resulting outputs.
The SVT-AV1 Encoder supports the following input formats:
8-bit yuv420p
10-bit yuv420p10le
In order to reduce the size of the input original YUV file, the SVT-AV1 Encoder uses a compressed 10-bit format allowing the software to achieve a higher speed and channel density levels. The conversion between the 10-bit yuv420p10le and the compressed 10-bit format is a lossless operation and is performed using the following steps.
This step consists of separating the 10 bit video samples into 8 bit and 2 bit planes so that each 10-bit picture will be represented as two separate pictures as shown in the figure below. As a result of the operation, the 2 least significant bits of the 10 bits will be written into a full byte.
10-bit yuv420p10le unpacked
The unpacking steps separates the 10bits into a group of 8 bits and a group of 2 bits, where the 2 bits are stored in a byte. In this step, every group of consecutive 4 bytes, each containing 2bits from the unpacking step, are compressed into one byte. As a result, each 10bit picture will be represented as two separate pictures as shown in the figure below.
10-bit yuv420p10le compressed
Now for a faster read of the samples, every 64x64 block of the 2 bit picture should be written into a one dimensional array. Therefore, the top left 64x64 sample block which is now written into a 16 bytes x 64 bytes after the compression of the 2bit samples, will be written into a 1024 bytes x 1 byte array as shown in the picture below.
64x64 block after 2 bit compression
64x64 block after unrolling
This section describes how to run the sample encoder application SvtAv1EncApp.exe (on Windows*) or SvtAv1EncApp (on Linux*) from the command line, including descriptions of the most commonly used input parameters and outputs.
The sample application typically takes the following command line parameters:
-c filename [Optional]
A text file that contains encoder parameters such as input file name, quantization parameter etc. Refer to the comments in the Config/Sample.cfg for specific details. The list of encoder parameters are also listed below. Note that command line parameters take precedence over the parameters included in the configuration file when there is a conflict.
-i filename [Required]
A YUV file (e.g. 8 bit 4:2:0 planar) containing the video sequence that will be encoded. The dimensions of each image are specified by -w and -h as indicated below.
-b filename [Optional]
The resulting encoded bit stream file in binary format. If none specified, no output bit stream will be produced by the encoder.
-w integer [Required]
The width of each input image in units of picture luma pixels, e.g. 1920
-h integer [Required]]
The height of each input image in units of picture luma pixels, e.g. 1080
-n integer [Optional]
The number of frames of the sequence to encode. e.g. 100. If the input frame count is larger than the number of frames in the input video, the encoder will loopback to the first frame when it is done.
--keyint integer [Optional]
The intra period defines the interval of frames after which you insert an Intra refresh. It is strongly recommended to use (multiple of 8) -1 the closest to 1 second (e.g. 55, 47, 31, 23 should be used for 60, 50, 30, (24 or 25) respectively). When using closed gop (-irefresh-type 2) add 1 to the value above (e.g. 56 instead of 55).
--rc integer [Optional]
This token sets the bitrate control encoding mode [1: Variable Bitrate, 0: Constant QP]. When --rc is set to 1, it is best to match the --lookahead (lookahead distance described in the next section) parameter to the --keyint. When --rc is set to 0, a qp value is expected with the use of the -q command line option otherwise a default value is assigned (25).
For example, the following command encodes 100 frames of the YUV video sequence into the bin bit stream file. The picture is 1920 luma pixels wide and 1080 pixels high using the Sample.cfg configuration. The QP equals 30 and the md5 checksum is not included in the bit stream.
SvtAv1EncApp.exe -c Sample.cfg -i CrowdRun_1920x1080.yuv -w 1920 -h 1080 -n 100 -q 30 --keyint 31 -b CrowdRun_1920x1080_qp30.bin
It should be noted that not all the encoder parameters present in the Sample.cfg can be changed using the command line.
Here are some sample encode command lines
SvtAv1EncApp -i input.yuv -w 1920 -h 1080 --fps 24 --rc 0 -q 30 --preset 8 -b output.ivf
SvtAv1EncApp -i input.yuv -w 1920 -h 1080 --fps 24 --rc 2 --tbr 10000 --preset 5 -b output.ivf
1 command line :
SvtAv1EncApp -i input.yuv -w 1920 -h 1080 --fps 24 --rc 0 -q 30 --preset 0 --irefresh-type 2 --passes 2 --stats stat_file.stat -b output.ivf
or
2 command lines :
SvtAv1EncApp -i input.yuv -w 1920 -h 1080 --fps 24 --rc 0 -q 30 --preset 8 --irefresh-type 2 --pass 1 --stats stat_file.stat
SvtAv1EncApp -i input.yuv -w 1920 -h 1080 --fps 24 --rc 0 -q 30 --preset 0 --irefresh-type 2 --pass 2 --stats stat_file.stat -b output.ivf
The encoder parameters present in the Sample.cfg file are listed in this table below along with their status of support, command line parameter and the range of values that the parameters can take.
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| InputFile | -i | any string | None | Input file path; "stdin" to take input from standard input stream |
| StreamFile | -b | any string | null | Output bitstream file path; "stdout" to emit output to standard output stream |
| ConfigFile | -c | any string | null | Configuration file path |
| ErrorFile | --errlog | any string | stderr | error log displaying configuration or encode errors |
| ReconFile | -o | any string | null | Recon file path. Optional output of recon. |
| StatFile | --stat-file | any string | Null | Path to statistics file if specified and StatReport is set to 1, per picture statistics are outputted in the file |
| Progress | --progress | [0,1,2] | 1 | Use --progress 0 to disable printing of frame processed when encoding, --progress 1 for default printing, and --progress 2 for aomenc style printing |
| NoProgress | --no-progress | [0,1] | 0 | --no-progress 1 is equivalent to --progress 0 and --no-progress 0 is equivalent to --progress 1 |
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| SourceWidth | -w | [64 - 4096] | None | Input source width |
| SourceHeight | -h | [0 - 2304] | None | Input source height |
| FrameToBeEncoded | -n | [0 - 2^64 -1] | 0 | Number of frames to be encoded, if number of frames is > number of frames in file, the encoder will loop to the beginning and continue the encode. Use -1 to not buffer. |
| BufferedInput | --nb | [-1, 1 to 2^31 -1] | -1 | number of frames to preload to the RAM before the start of the encode If --nb = 100 and -n 1000 -- > the encoder will encode the first 100 frames of the video 10 times |
| EncoderColorFormat | --color-format | [0-3] | 1 | Set encoder color format(EB_YUV400, EB_YUV420, EB_YUV422, EB_YUV444) |
| Profile | --profile | [0-2] | 0 | Bitstream profile number to use (0: main profile[default], 1: high profile, 2: professional profile) |
| FrameRate | --fps | [0 - 2^64 -1] | 25 | If the number is less than 1000, the input frame rate is an integer number between 1 and 60, else the input number is in Q16 format (shifted by 16 bits) [Max allowed is 240 fps] |
| FrameRateNumerator | --fps-num | [0 - 2^64 -1] | 0 | Frame rate numerator e.g. 6000 |
| FrameRateDenominator | --fps-denom | [0 - 2^64 -1] | 0 | Frame rate denominator e.g. 100 |
| EncoderBitDepth | --input-depth | [8 , 10] | 8 | specifies the bit depth of the input video |
| Encoder16BitPipeline | --16bit-pipeline | [0 , 1] | 0 | Bit depth for enc-dec(0: lbd[default], 1: hbd) |
| HierarchicalLevels | --hierarchical-levels | [0 - 5] | 4 | 0 : Flat4: 5-Level HierarchyMinigop Size = (2^HierarchicalLevels) (e.g. 0 == > 0B pyramid, 1 == > 1B pyramid, 2 == > 3B pyramid, 3 == > 7B pyramid, 4 == > 15B Pyramid) |
| PredStructure | --pred-struct | [0-2] | 2 | Set prediction structure( 0: low delay P, 1: low delay B, 2: random access [default]) |
| HighDynamicRangeInput | --enable-hdr | [0-1] | 0 | Enable high dynamic range(0: OFF[default], ON: 1) |
| Asm | --asm | [0 - 11] or [c, mmx, sse, sse2, sse3, ssse3, sse4_1, sse4_2, avx, avx2, avx512, max] | 11 or max | Limit assembly instruction set ("0" is equivalent to "c", "1" is "mmx" etc, max value is "11" or "max"), by default select highest assembly instruction that is supported by CPU |
| LogicalProcessorNumber | --lp | [0, total number of logical processor] | 0 | The number of logical processor which encoder threads run on.Refer to Appendix A.1 |
| UnpinExecution | --unpin | [0, 1] | 1 | Allows the execution to be pined/unpined to/from a specific number of cores.--unpin is overwritten to 0 when --ss is set to 0 or 1. 0=OFF, 1= ON |
| TargetSocket | --ss | [-1,1] | -1 | For dual socket systems, this can specify which socket the encoder runs on.Refer to Appendix A.1 |
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| RateControlMode | --rc | [0 - 2] | 0 | 0 = CQP , 1 = VBR , 2 = CVBR |
| QP | -q | [0 - 63] | 50 | Quantization parameter used when RateControl is set to 0 |
| TargetBitRate | --tbr | [1 - 4294967] | 7000 | Target bitrate in kilobits per second when RateControlMode is set to 1, or 2 |
| UseQpFile | --use-q-file | [0-1] | 0 | When set to 1, overwrite the picture qp assignment using qp values in QpFile |
| QpFile | --qpfile | any string | Null | Path to qp file |
| MaxQpAllowed | --max-qp | [0 - 63] | Null | Maximum (worst) quantizer[0-63] |
| MinQpAllowed | --min-qp | [0 - 63] | Null | Minimum (best) quantizer[0-63] |
| AdaptiveQuantization | --adaptive-quantization | [0 - 2] | 0 | 0 = OFF , 1 = variance base using segments , 2 = Deltaq pred efficiency (default) |
| VBVBufSize | --vbv-bufsize | [1 - 4294967] | 1 second TargetBitRate | VBV Buffer Size when RateControl is 2. |
| UseFixedQIndexOffsets | --use-fixed-qindex-offsets | [0 - 1] | 0 | 0 = OFF, 1 = enable fixed qindex offset based on temporal layer and frame type when rc mode is 0. qindex offsets are specified by the following arguments |
| QIndexOffsets | --qindex-offsets | [v0,v1,..,vn] | [0,0,..,0] | list of qindex offsets vi, enclosed in [], seperated by ,. vi is in the range of [-256,255]. this argument should be used after hierarchical-levels, the number of qindex offsets equals to hierarchical-levels + 1 |
| KeyFrameQIndexOffset | --key-frame-qindex-offset | [-256, 255] | 0 | qindex offset for Key frame |
| ChromaQIndexOffsets | --chroma-qindex-offsets | [v0,v1,..,vn] | [0,0,..,0] | list of qindex offset vi, enclosed in [], seperated by ,. vi is in the range of [-256, 255]. this argument should be used after hierarchical-levels, the number of qindex offsets equals to hierarchical-levels + 1 |
| KeyFrameChromaQIndexOffset | --key-frame-chroma-qindex-offset | [-256, 255] | 0 | chroma qindex offset for Key frame |
use-fixed-qindex-offsets and associtated arguments (hierarchical-levels, qindex-offsets, chroma-qindex-offsets, key-frame-qindex-offset, key-frame-chroma-qindex-offset) are used together to specify the qindex offsets based on frame type and temporal layer when rc mode = 0.
qp value specified by -q argument is assigned to the pictures at the highest temporal layer. it is first converted to qindex, then corresponding qindex offsets are added on top of it based on frame types (Key/Inter) and temporal layer id.
qindex offset can be negative. the final qindex value will be clamped in the valid min/max qindex range.
for chroma plane, after deciding the qindex for the luma plane, corresponding chroma qindex offsets are added on top of the luma plane qindex based on frame types and temporal layer id.
--qindex-offsets and --chroma-qindex-offsets have to be used after the --hierachical-levels parameter. number of qindex offsets should be hierachical levels plus 1.
an example command line is: "--rc 0 -q 42 --hierarchical-levels 3 --use-fixed-qindex-offsets 1 --qindex-offsets [-12,-8,-4,0] --key-frame-qindex-offset -20 --key-frame-chroma-qindex-offset -6 --chroma-qindex-offsets [-6,0,12,24]"
for this command line, corresponding qindex are:
| Frame Type | Luma qindex | Chroma qindex |
|---|---|---|
| Key Frame | 148 (42x4 - 20) | 142 (148 - 6) |
| Layer0 Frame | 156 (42x4 - 12) | 150 (156 - 6) |
| Layer1 Frame | 160 (42x4 - 8) | 160 (160 + 0) |
| Layer2 Frame | 164 (42x4 - 4) | 176 (164 + 12) |
| Layer3 Frame | 168 (42x4 + 0) | 192 (168 + 24) |
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| Passes | --passes | [1-2] | 1 | Number of passes (1: one pass encode, 2: two passes encode) |
| Pass | --pass | [1-2] | Null | Specify which pass the run is on (1=First Pass, 2=Second Pass) |
| Stats | --stats | any string | Null | Output stat file containing information from first pass |
| OutputStatFile | --output-stat-file | any string | Null | Output stat file for first pass |
| InputStatFile | --input-stat-file | any string | Null | Input stat file for second pass |
| VBRBiasPct | --bias-pct | [0 - 100] | 50 | 2pass CBR/VBR bias percent (0=CBR, 100=VBR) |
| MinSectionPct | --minsection-pct | [0 - ] | 0 | 2pass VBR GOP min bitrate (percent of target) |
| MaxSectionPct | --maxsection-pct | [0 - ] | 2000 | 2pass VBR GOP max bitrate (percent of target) |
| UnderShortPct | --undershoot-pct | [0 - 100] | 25 | Datarate undershoot (min) target (percent) |
| OverShortPct | --overshoot-pct | [0 - 100] | 25 | Datarate overshoot (max) target (percent) |
| RecodeLoop | --recode-loop | [0 - 3] | 2 | Recode loop levels for 2pass VBR (0=disable reencode, 1=reencode key frames, 2=reencode base layer frames, 3=reencode all frames) |
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| IntraPeriod | --keyint | [-2 - 2^31-2] | -2 | Intra period interval(frames) -2: default intra period , -1: No intra update or an integer >= 0. if RateControlMode >= 1 intra-period limited to [-2, 255] |
| IntraRefreshType | --irefresh-type | [1 - 2] | 2 | 1: CRA (Open GOP), 2: IDR (Closed GOP)[default] |
| Configuration file parameter | Command line | Range | Default | Description |
|---|---|---|---|---|
| EncoderMode | --preset | [0 - 8] | 8 | Encoder Preset [0,1,2,3,4,5,6,7,8] 0 = highest quality, 8 = highest speed |
| CompressedTenBitFormat | --compressed-ten-bit-format | [0-1] | 0 | Offline packing of the 2bits: requires two bits packed input (0: OFF, 1: ON) |
| TileRow | --tile-rows | [0-6] | 0 | log2 of tile rows |
| TileCol | --tile-columns | [0-6] | 0 | log2 of tile columns |
| LookAheadDistance | --lookahead | [0 - 120] | 33 | When RateControlMode is set to 1 or 2 it's strongly recommended to set this parameter to be equal to the Intra period value (such is the default set by the encoder). When RateControlMode is set to 0, it is recommended for this value to be set to a size of a minigop (e.g. 16 for --hierarchichal-levels 4) |
| LoopFilterDisable | --disable-dlf | [0-1] | 0 | Disable loop filter(0: loop filter enabled[default] ,1: loop filter disabled) |
| EnableTPLModel | --enable-tpl-la | [0-1] | 1 | RDO based on frame temporal dependency (0: off, 1: backward source based) |
| CDEFLevel | --cdef-level | [0-5] | -1 | CDEF Level, 0: OFF, 1-5: ON with 64,16,8,4,1 step refinement, -1: DEFAULT |
| RestorationFilter | --enable-restoration-filtering | [0-1] | -1 | Enable restoration filtering , 0 = OFF, 1 = ON, -1 = DEFAULT |
| SelfGuidedFilterMode | --sg-filter-mode | [0-4] | -1 | Self-guided filter mode (0:OFF, 1: step 0, 2: step 1, 3: step 4, 4: step 16, -1: DEFAULT) |
| WienerFilterMode | --wn-filter-mode | [0-3] | -1 | Wiener filter mode (0:OFF, 1: 3-Tap luma/ 3-Tap chroma, 2: 5-Tap luma/ 5-Tap chroma, 3: 7-Tap luma/ 7-Tap chroma, -1: DEFAULT) |
| Mfmv | --enable-mfmv | [0-1] | -1 | Enable motion field motion vector, 0 = OFF, 1 = ON, -1 = DEFAULT |
| RedundantBlock | --enable-redundant-blk | [0-1] | -1 | Enable redundant block skipping same neighbors non-square partitions, 0 = OFF, 1 = ON, -1 = DEFAULT |
| SpatialSSEfl | --enable-spatial-sse-full-loop-level | [0-1] | -1 | Enable spatial sse full loop, 0 = OFF, 1 = ON, -1 = DEFAULT |
| OverBoundryBlock | --enable-over-bndry-blk | [0-1] | -1 | Enable over boundary block mode, 0 = OFF, 1 = ON, -1 = DEFAULT |
| NewNearestCombInjection | --enable-new-nrst-near-comb | [0-1] | -1 | Enable new nearest near comb injection, 0 = OFF, 1 = ON, -1 = DEFAULT |
| NsqTable | --enable-nsq-table-use | [0-1] | -1 | Enable nsq table, 0 = OFF, 1 = ON, -1 = DEFAULT |
| FrameEndCdfUpdate | --enable-framend-cdf-upd-mode | [0-1] | -1 | Enable frame end cdf update mode, 0 = OFF, 1 = ON, -1 = DEFAULT |
| ChromaMode | --chroma-mode | [0-3] | -1 | Chroma Mode -1 = DEFAULT 0 = Full chroma search @ MD 1 = Fast chroma search @ MD 2 = Chroma blind @ MD + CFL @ EP 3 = Chroma blind @ MD + no CFL @ EP |
| DisableCfl | --disable-cfl | [0-1] | -1 | Disable chroma from luma (CFL), 0 = OFF (do not disable), 1 = ON (disable), -1 = DEFAULT |
| LocalWarpedMotion | --enable-local-warp | [0-1] | -1 | Enable warped motion use , 0 = OFF, 1 = ON, -1 DEFAULT |
| GlobalMotion | --enable-global-motion | [0-1] | 1 | Enable global motion (0: OFF, 1: ON [default]) |
| PicBasedRateEst | --enable-pic-based-rate-est | [0-1] | -1 | Enable picture based rate estimation. Only active with lp 1 (0: OFF, 1: ON, -1: DEFAULT) |
| IntraAngleDelta | --enable-intra-angle-delta | [0-1] | -1 | Enable intra angle delta filtering (0: OFF, 1: ON, -1 = DEFAULT |
| InterIntraCompound | --enable-interintra-comp | [0-1] | -1 | Enable inter intra compound, 0 = OFF, 1 = ON, -1 = DEFAULT |
| Paeth | --enable-paeth | [0-1] | -1 | Enable Intra Paeth pred, 0 = OFF, 1 = ON, -1 = DEFAULT |
| Smooth | --enable-smooth | [0-1] | -1 | Enable Intra Smooth pred, 0 = OFF, 1 = ON, -1 = DEFAULT |
| MultiReferencePictures | --mrp-level | [0-9] | -1 | Multi reference frame levels( 0: OFF, 1: FULL, 2: Level1 .. 9: Level8, -1: DEFAULT) |
| Obmc | --obmc-level | [0-3] | -1 | OBMC Level(0: OFF, 1: Fully ON, 2 and 3 are faster levels, -1: DEFAULT) |
| RDOQ | --rdoq-level | [0-1] | -1 | Enable RDOQ, 0 = OFF, 1 = ON, -1 = DEFAULT |
| FilterIntra | --filter-intra-level | [0-1] | -1 | Enable filter intra prediction mode (0: OFF, 1: ON [default]) |
| IntraEdgeFilter | --enable-intra-edge-filter | [0-1] | -1 | Enable intra edge filter (0: OFF, 1: ON, -1: DEFAULT) |
| PredMe | --pred-me | [0-5] | -1 | Closed loop motion search. Set predictive me level: -1 = DEFAULT 0 = OFF 1 = 7x5 full-pel search + sub-pel refinement off 2 = 7x5 full-pel search + (H + V) sub-pel refinement only = 4 half-pel + 4 quarter-pel = 8 positions + pred_me_distortion to pa_me_distortion deviation on 3 = 7x5 full-pel search + (H + V + D only ~ the best) sub-pel refinement = up to 6 half-pel + up to 6 quarter-pel = up to 12 positions + pred_me_distortion to pa_me_distortion deviation on 4 = 7x5 full-pel search + (H + V + D) sub-pel refinement = 8 half-pel + 8 quarter-pel = 16 positions + pred_me_distortion to pa_me_distortion deviation on 5 = 7x5 full-pel search + (H + V + D) sub-pel refinement = 8 half-pel + 8 quarter-pel = 16 positions + pred_me_distortion to pa_me_distortion deviation off |
| Bipred3x3 | --bipred-3x3 | [0-2] | -1 | Set bipred3x3 injection, 0 = OFF, 1 = ON FULL, 2 = Reduced set, -1 = DEFAULT |
| CompoundLevel | --compound | [0-2] | -1 | Set compound mode: -1 = DEFAULT 0 = OFF: No compond mode search : AVG only 1 = ON: compond mode search: AVG/DIST/DIFF 2 = ON: AVG/DIST/DIFF/WEDGE |
| UseDefaultMeHme | --use-default-me-hme | [0-1] | 1 | 0 : Overwrite Default ME HME parameters1 : Use default ME HME parameters, dependent on width and height |
| HME | --hme | [0-1] | 1 | Enable HME, 0 = OFF, 1 = ON |
| HMELevel0 | --hme-l0 | [0-1] | 1 | Enable HME Level 0 , 0 = OFF, 1 = ON |
| HMELevel1 | --hme-l1 | [0-1] | Depends on input resolution | Enable HME Level 1 , 0 = OFF, 1 = ON |
| HMELevel2 | --hme-l2 | [0-1] | Depends on input resolution | Enable HME Level 2 , 0 = OFF, 1 = ON |
| ExtBlockFlag | --ext-block | [0-1] | Depends on --preset | Enable the non-square block 0=OFF, 1= ON |
| SearchAreaWidth | --search-w | [1 - 480] | Depends on input resolution | Search Area in Width |
| SearchAreaHeight | --search-h | [1 - 480] | Depends on input resolution | Search Area in Height |
| ScreenContentMode | --scm | [0 - 2] | 0 | Enable Screen Content Optimization mode (0: OFF, 1: ON, 2: Content Based Detection) |
| IntraBCMode | --intrabc-mode | [-1 - 3]] | -1 | IntraBC mode (0 = OFF, 1 = ON slow, 1 = ON faster, 2 = ON fastest, -1 = DEFAULT) |
| HighBitDepthModeDecision | --hbd-md | [0-2] | 1 | Enable high bit depth mode decision(0: OFF, 1: ON partially[default],2: fully ON) |
| PaletteLevel | --palette-level | [-1 - 6] | -1 | Enable Palette mode (-1: DEFAULT (ON at level6 when SC is detected), 0: OFF 1: ON Level 1, ...6: ON Level6 ) |
| UnrestrictedMotionVector | --umv | [0-1] | 1 | Enables or disables unrestriced motion vectors, 0 = OFF(motion vectors are constrained within tile boundary), 1 = ON. For MCTS support, set --umv 0 |
| Injector | --inj | [0-1] | 0 | Inject pictures at defined frame rate(0: OFF[default],1: ON) |
| InjectorFrameRate | --inj-frm-rt | Null | Null | Set injector frame rate |
| SpeedControlFlag | --speed-ctrl | [0-1] | 0 | Enable speed control(0: OFF[default], 1: ON) |
| FilmGrain | --film-grain | [0-50] | 0 | Enable film grain(0: OFF[default], 1 - 50: Level of denoising for film grain) |
| AltRefLevel | --tf-level | [0-3] | -1 | Enable automatic alt reference frames(-1: Default; 0: OFF; 1: ON; 2 and 3: Faster levels) |
| AltRefStrength | --altref-strength | [0-6] | 5 | AltRef filter strength([0-6], default: 5) |
| AltRefNframes | --altref-nframes | [0-10] | 7 | AltRef max frames([0-10], default: 7) |
| EnableOverlays | --enable-overlays | [0-1] | 0 | Enable the insertion of an extra picture called overlayer picture which will be used as an extra reference frame for the base-layer picture(0: OFF[default], 1: ON) |
| SquareWeight | --sqw | 0 for off and any whole number percentage | 100 | Weighting applied to square/h/v shape costs when deciding if a and b shapes could be skipped. Set to 100 for neutral weighting, lesser than 100 for faster encode and BD-Rate loss, and greater than 100 for slower encode and BD-Rate gain |
| ChannelNumber | --nch | [1 - 6] | 1 | Number of encode instances |
| StatReport | --enable-stat-report | [0-1] | 0 | When set to 1, calculates and outputs average PSNR values |
the DEFAULT option would allow the encoder to choose adaptively any of the values in the range for that option whether on a preset, picture, or SB level.
LogicalProcessorNumber (--lp) and TargetSocket (--ss) parameters are used to management thread affinity on Windows and Ubuntu OS. These are some examples how you use them together.
If LogicalProcessorNumber and TargetSocket are not set, threads are managed by OS thread scheduler.
SvtAv1EncApp.exe -i in.yuv -w 3840 -h 2160 --lp 40
If only LogicalProcessorNumber is set, threads run on 40 logical processors. Threads may run on dual sockets if 40 is larger than logical processor number of a socket.
NOTE: On Windows, thread affinity can be set only by group on system with more than 64 logical processors. So, if 40 is larger than logical processor number of a single socket, threads run on all logical processors of both sockets.
SvtAv1EncApp.exe -i in.yuv -w 3840 -h 2160 --ss 1
If only TargetSocket is set, threads run on all the logical processors of socket 1.
SvtAv1EncApp.exe -i in.yuv -w 3840 -h 2160 --lp 20 --ss 0
If both LogicalProcessorNumber and TargetSocket are set, threads run on 20 logical processors of socket 0. Threads guaranteed to run only on socket 0 if 20 is larger than logical processor number of socket 0.
The (-unpin) option allows the user to pin/unpin the execution to/from a specific number of cores.
The combinational use of (-unpin) with (-lp) results in memory reduction while allowing the execution to work on any of the cores and not restrict it to specific cores.
This is an example on how to use them together.
so -lp 4 with -unpin 0 would restrict the encoder to work on cpu0-3 and reduce the resource allocation to only what's needed to using 4 cores. -lp 4 with -unpin 1, would reduce the allocation to what's needed for 4 cores but not restrict the encoder to run on cpu 0-3, in this case the encoder might end up using more than 4 cores due to the multi-threading nature of the encoder, but would at least allow for more multiple -lp4 encodes to run on the same machine without them being all restricted to run on cpu 0-3 or overflow the memory usage.
Example: 72 core machine:
72 jobs x --lp 1 --unpin 1 (In order to maximize the CPU utilization 72 jobs are run simultaneously with each job utilitizing 1 core without being pined to a specific core)
36 jobs x --lp 2 --unpin 1
18 jobs x --lp 4 --unpin 1
(-ss) and (-unpin 1) is not a valid combination.(-unpin) is overwritten to 0 when (-ss) is used.