.\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.49.2.
.TH AOMENC "1" "September 2022" "aomenc 3.5.0" "User Commands"
.SH NAME
aomenc \- manual page for aomenc 3.5.0
.SH SYNOPSIS
.B aomenc
\fI\,<options> -o dst_filename src_filename\/\fR
.SH OPTIONS
.TP
\fB\-\-help\fR
Show usage options and exit
.TP
\fB\-c\fR <arg>, \fB\-\-cfg=\fR<arg>
Config file to use
.TP
\fB\-D\fR,       \fB\-\-debug\fR
Debug mode (makes output deterministic)
.TP
\fB\-o\fR <arg>, \fB\-\-output=\fR<arg>
Output filename
.TP
\fB\-\-codec=\fR<arg>
Codec to use
.TP
\fB\-p\fR <arg>, \fB\-\-passes=\fR<arg>
Number of passes (1/2/3)
.TP
\fB\-\-pass=\fR<arg>
Pass to execute (1/2/3)
.TP
\fB\-\-fpf=\fR<arg>
First pass statistics file name
.TP
\fB\-\-limit=\fR<arg>
Stop encoding after n input frames
.TP
\fB\-\-skip=\fR<arg>
Skip the first n input frames
.TP
\fB\-\-good\fR
Use Good Quality Deadline
.TP
\fB\-\-rt\fR
Use Realtime Quality Deadline
.TP
\fB\-\-allintra\fR
Use all intra mode
.TP
\fB\-q\fR,       \fB\-\-quiet\fR
Do not print encode progress
.TP
\fB\-v\fR,       \fB\-\-verbose\fR
Show encoder parameters
.TP
\fB\-\-psnr=\fR<arg>
Show PSNR in status line (0: Disable PSNR status line display, 1: PSNR calculated using input bit\-depth (default), 2: PSNR calculated using stream bit\-depth); takes default option when arguments are not specified
.TP
\fB\-\-webm\fR
Output WebM (default when WebM IO is enabled)
.TP
\fB\-\-ivf\fR
Output IVF
.TP
\fB\-\-obu\fR
Output OBU
.TP
\fB\-\-q\-hist=\fR<arg>
Show quantizer histogram (n\-buckets)
.TP
\fB\-\-rate\-hist=\fR<arg>
Show rate histogram (n\-buckets)
.TP
\fB\-\-disable\-warnings\fR
Disable warnings about potentially incorrect encode settings
.TP
\fB\-y\fR,       \fB\-\-disable\-warning\-prompt\fR
Display warnings, but do not prompt user to continue
.TP
\fB\-\-test\-decode=\fR<arg>
Test encode/decode mismatch
.IP
off, fatal, warn
.SS "Encoder Global Options:"
.TP
\fB\-\-nv12\fR
Input file is NV12
.TP
\fB\-\-yv12\fR
Input file is YV12
.TP
\fB\-\-i420\fR
Input file is I420 (default)
.TP
\fB\-\-i422\fR
Input file is I422
.TP
\fB\-\-i444\fR
Input file is I444
.TP
\fB\-u\fR <arg>, \fB\-\-usage=\fR<arg>
Usage profile number to use (0: good, 1: rt, 2: allintra)
.TP
\fB\-t\fR <arg>, \fB\-\-threads=\fR<arg>
Max number of threads to use
.TP
\fB\-\-profile=\fR<arg>
Bitstream profile number to use
.TP
\fB\-w\fR <arg>, \fB\-\-width=\fR<arg>
Frame width
.TP
\fB\-h\fR <arg>, \fB\-\-height=\fR<arg>
Frame height
.TP
\fB\-\-forced_max_frame_width=\fR<arg>
Maximum frame width value to force
.TP
\fB\-\-forced_max_frame_height=\fR<arg>
Maximum frame height value to force
.TP
\fB\-\-stereo\-mode=\fR<arg>
Stereo 3D video format
.IP
mono, left\-right, bottom\-top, top\-bottom, right\-left
.TP
\fB\-\-timebase=\fR<arg>
Output timestamp precision (fractional seconds)
.TP
\fB\-\-fps=\fR<arg>
Stream frame rate (rate/scale)
.TP
\fB\-\-global\-error\-resilient=\fR<arg>
Enable global error resiliency features
.TP
\fB\-b\fR <arg>, \fB\-\-bit\-depth=\fR<arg>
Bit depth for codec
8, 10, 12
.TP
\fB\-\-input\-bit\-depth=\fR<arg>
Bit depth of input
.TP
\fB\-\-lag\-in\-frames=\fR<arg>
Max number of frames to lag
.TP
\fB\-\-large\-scale\-tile=\fR<arg>
Large scale tile coding (0: off (default), 1: on (ivf output only))
.TP
\fB\-\-monochrome\fR
Monochrome video (no chroma planes)
.TP
\fB\-\-full\-still\-picture\-hdr\fR
Use full header for still picture
.TP
\fB\-\-use\-16bit\-internal\fR
Force use of 16\-bit pipeline
.TP
\fB\-\-annexb=\fR<arg>
Save as Annex\-B
.SS "Rate Control Options:"
.TP
\fB\-\-drop\-frame=\fR<arg>
Temporal resampling threshold (buf %)
.TP
\fB\-\-resize\-mode=\fR<arg>
Frame resize mode
.TP
\fB\-\-resize\-denominator=\fR<arg>
Frame resize denominator
.TP
\fB\-\-resize\-kf\-denominator=\fR<arg>
Frame resize keyframe denominator
.TP
\fB\-\-superres\-mode=\fR<arg>
Frame super\-resolution mode
.TP
\fB\-\-superres\-denominator=\fR<arg>
Frame super\-resolution denominator
.TP
\fB\-\-superres\-kf\-denominator=\fR<arg>
Frame super\-resolution keyframe denominator
.TP
\fB\-\-superres\-qthresh=\fR<arg>
Frame super\-resolution qindex threshold
.IP
\fB\-\-superres\-kf\-qthresh=\fR<arg> Frame super\-resolution keyframe qindex threshold
\fB\-\-end\-usage=\fR<arg>           Rate control mode
.IP
vbr, cbr, cq, q
.TP
\fB\-\-target\-bitrate=\fR<arg>
Bitrate (kbps)
.TP
\fB\-\-min\-q=\fR<arg>
Minimum (best) quantizer
.TP
\fB\-\-max\-q=\fR<arg>
Maximum (worst) quantizer
.TP
\fB\-\-undershoot\-pct=\fR<arg>
Datarate undershoot (min) target (%)
.TP
\fB\-\-overshoot\-pct=\fR<arg>
Datarate overshoot (max) target (%)
.TP
\fB\-\-buf\-sz=\fR<arg>
Client buffer size (ms)
.TP
\fB\-\-buf\-initial\-sz=\fR<arg>
Client initial buffer size (ms)
.TP
\fB\-\-buf\-optimal\-sz=\fR<arg>
Client optimal buffer size (ms)
.TP
\fB\-\-bias\-pct=\fR<arg>
CBR/VBR bias (0=CBR, 100=VBR)
.TP
\fB\-\-minsection\-pct=\fR<arg>
GOP min bitrate (% of target)
.TP
\fB\-\-maxsection\-pct=\fR<arg>
GOP max bitrate (% of target)
.SS "Keyframe Placement Options:"
.TP
\fB\-\-enable\-fwd\-kf=\fR<arg>
Enable forward reference keyframes
.TP
\fB\-\-kf\-min\-dist=\fR<arg>
Minimum keyframe interval (frames)
.TP
\fB\-\-kf\-max\-dist=\fR<arg>
Maximum keyframe interval (frames)
.TP
\fB\-\-disable\-kf\fR
Disable keyframe placement
.TP
\fB\-\-sframe\-dist=\fR<arg>
S\-Frame interval (frames)
.TP
\fB\-\-sframe\-mode=\fR<arg>
S\-Frame insertion mode (1..2)
.SS "AV1 Specific Options:"
.TP
\fB\-\-cpu\-used=\fR<arg>
Speed setting (0..6 in good mode, 5..10 in realtime mode, 0..9 in all intra mode)
.TP
\fB\-\-auto\-alt\-ref=\fR<arg>
Enable automatic alt reference frames
.TP
\fB\-\-sharpness=\fR<arg>
Bias towards block sharpness in rate\-distortion optimization of transform coefficients (0..7), default is 0
.TP
\fB\-\-static\-thresh=\fR<arg>
Motion detection threshold
.TP
\fB\-\-row\-mt=\fR<arg>
Enable row based multi\-threading (0: off, 1: on (default))
.TP
\fB\-\-fp\-mt=\fR<arg>
Enable frame parallel multi\-threading (0: off (default), 1: on)
.TP
\fB\-\-tile\-columns=\fR<arg>
Number of tile columns to use, log2
.TP
\fB\-\-tile\-rows=\fR<arg>
Number of tile rows to use, log2
.TP
\fB\-\-enable\-tpl\-model=\fR<arg>
RDO based on frame temporal dependency (0: off, 1: backward source based); required for deltaq mode
.TP
\fB\-\-enable\-keyframe\-filtering=\fR<arg>
Apply temporal filtering on key frame (0: no filter, 1: filter without overlay (default), 2: filter with overlay \- experimental, may break random access in players)
.TP
\fB\-\-arnr\-maxframes=\fR<arg>
AltRef max frames (0..15)
.TP
\fB\-\-arnr\-strength=\fR<arg>
AltRef filter strength (0..6)
.TP
\fB\-\-tune=\fR<arg>
Distortion metric tuned with
.IP
psnr, ssim, vmaf_with_preprocessing, vmaf_without_preprocessing, vmaf, vmaf_neg, butteraugli
.TP
\fB\-\-cq\-level=\fR<arg>
Constant/Constrained Quality level
.TP
\fB\-\-max\-intra\-rate=\fR<arg>
Max I\-frame bitrate (pct)
.TP
\fB\-\-max\-inter\-rate=\fR<arg>
Max P\-frame bitrate (pct)
.TP
\fB\-\-gf\-cbr\-boost=\fR<arg>
Boost for Golden Frame in CBR mode (pct)
.TP
\fB\-\-lossless=\fR<arg>
Lossless mode (0: false (default), 1: true)
.TP
\fB\-\-enable\-cdef=\fR<arg>
Enable the constrained directional enhancement filter (0: false, 1: true (default), 2: disable for non\-reference frames)
.TP
\fB\-\-enable\-restoration=\fR<arg>
Enable the loop restoration filter (0: false (default in realtime mode), 1: true (default in non\-realtime mode))
.TP
\fB\-\-enable\-rect\-partitions=\fR<arg>
Enable rectangular partitions (0: false, 1: true (default))
.TP
\fB\-\-enable\-ab\-partitions=\fR<arg>
Enable ab partitions (0: false, 1: true (default))
.TP
\fB\-\-enable\-1to4\-partitions=\fR<arg>
Enable 1:4 and 4:1 partitions (0: false, 1: true (default))
.TP
\fB\-\-min\-partition\-size=\fR<arg>
Set min partition size (4:4x4, 8:8x8, 16:16x16, 32:32x32, 64:64x64, 128:128x128); with 4k+ resolutions or higher speed settings, min partition size will have a minimum of 8
.TP
\fB\-\-max\-partition\-size=\fR<arg>
Set max partition size (4:4x4, 8:8x8, 16:16x16, 32:32x32, 64:64x64, 128:128x128)
.TP
\fB\-\-enable\-dual\-filter=\fR<arg>
Enable dual filter (0: false, 1: true (default))
.TP
\fB\-\-enable\-chroma\-deltaq=\fR<arg>
Enable chroma delta quant (0: false (default), 1: true)
.TP
\fB\-\-enable\-intra\-edge\-filter=\fR<arg>
Enable intra edge filtering (0: false, 1: true (default))
.TP
\fB\-\-enable\-order\-hint=\fR<arg>
Enable order hint (0: false, 1: true (default))
.TP
\fB\-\-enable\-tx64=\fR<arg>
Enable 64\-pt transform (0: false, 1: true (default))
.TP
\fB\-\-enable\-flip\-idtx=\fR<arg>
Enable extended transform type (0: false, 1: true (default)) including FLIPADST_DCT, DCT_FLIPADST, FLIPADST_FLIPADST, ADST_FLIPADST, FLIPADST_ADST, IDTX, V_DCT, H_DCT, V_ADST, H_ADST, V_FLIPADST, H_FLIPADST
.TP
\fB\-\-enable\-rect\-tx=\fR<arg>
Enable rectangular transform (0: false, 1: true (default))
.TP
\fB\-\-enable\-dist\-wtd\-comp=\fR<arg>
Enable distance\-weighted compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-masked\-comp=\fR<arg>
Enable masked (wedge/diff\-wtd) compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-onesided\-comp=\fR<arg>
Enable one sided compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-interintra\-comp=\fR<arg>
Enable interintra compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-smooth\-interintra=\fR<arg>
Enable smooth interintra mode (0: false, 1: true (default))
.TP
\fB\-\-enable\-diff\-wtd\-comp=\fR<arg>
Enable difference\-weighted compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-interinter\-wedge=\fR<arg>
Enable interinter wedge compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-interintra\-wedge=\fR<arg>
Enable interintra wedge compound (0: false, 1: true (default))
.TP
\fB\-\-enable\-global\-motion=\fR<arg>
Enable global motion (0: false, 1: true (default))
.TP
\fB\-\-enable\-warped\-motion=\fR<arg>
Enable local warped motion (0: false, 1: true (default))
.IP
\fB\-\-enable\-filter\-intra=\fR<arg> Enable filter intra prediction mode (0: false, 1: true (default))
\fB\-\-enable\-smooth\-intra=\fR<arg> Enable smooth intra prediction modes (0: false, 1: true (default))
\fB\-\-enable\-paeth\-intra=\fR<arg>  Enable Paeth intra prediction mode (0: false, 1: true (default))
\fB\-\-enable\-cfl\-intra=\fR<arg>    Enable chroma from luma intra prediction mode (0: false, 1: true (default))
\fB\-\-enable\-diagonal\-intra=\fR<arg>
.IP
Enable diagonal (D45 to D203) intra prediction modes, which are a subset of directional modes; has no effect if enable\-directional\-intra is 0 (0: false, 1: true (default))
.TP
\fB\-\-force\-video\-mode=\fR<arg>
Force video mode (0: false, 1: true (default))
.TP
\fB\-\-enable\-obmc=\fR<arg>
Enable OBMC (0: false, 1: true (default))
.TP
\fB\-\-enable\-overlay=\fR<arg>
Enable coding overlay frames (0: false, 1: true (default))
.TP
\fB\-\-enable\-palette=\fR<arg>
Enable palette prediction mode (0: false, 1: true (default))
.TP
\fB\-\-enable\-intrabc=\fR<arg>
Enable intra block copy prediction mode (0: false, 1: true (default))
.TP
\fB\-\-enable\-angle\-delta=\fR<arg>
Enable intra angle delta (0: false, 1: true (default))
.TP
\fB\-\-disable\-trellis\-quant=\fR<arg>
Disable trellis optimization of quantized coefficients (0: false 1: true  2: true for rd search 3: true for estimate yrd search (default))
.TP
\fB\-\-enable\-qm=\fR<arg>
Enable quantisation matrices (0: false (default), 1: true)
.TP
\fB\-\-qm\-min=\fR<arg>
Min quant matrix flatness (0..15), default is 8
.TP
\fB\-\-qm\-max=\fR<arg>
Max quant matrix flatness (0..15), default is 15
.IP
\fB\-\-reduced\-tx\-type\-set=\fR<arg> Use reduced set of transform types
\fB\-\-use\-intra\-dct\-only=\fR<arg>  Use DCT only for INTRA modes
\fB\-\-use\-inter\-dct\-only=\fR<arg>  Use DCT only for INTER modes
\fB\-\-use\-intra\-default\-tx\-only=\fR<arg>
.IP
Use Default\-transform only for INTRA modes
.TP
\fB\-\-quant\-b\-adapt=\fR<arg>
Use adaptive quantize_b
.IP
\fB\-\-coeff\-cost\-upd\-freq=\fR<arg> Update freq for coeff costs. 0: SB, 1: SB Row per Tile, 2: Tile, 3: Off
\fB\-\-mode\-cost\-upd\-freq=\fR<arg>  Update freq for mode costs. 0: SB, 1: SB Row per Tile, 2: Tile, 3: Off
\fB\-\-mv\-cost\-upd\-freq=\fR<arg>    Update freq for mv costs. 0: SB, 1: SB Row per Tile, 2: Tile, 3: Off
\fB\-\-frame\-parallel=\fR<arg>      Enable frame parallel decodability features (0: false (default), 1: true)
\fB\-\-error\-resilient=\fR<arg>     Enable error resilient features (0: false (default), 1: true)
\fB\-\-aq\-mode=\fR<arg>             Adaptive quantization mode (0: off (default), 1: variance 2: complexity, 3: cyclic refresh)
\fB\-\-deltaq\-mode=\fR<arg>         Delta qindex mode (0: off, 1: deltaq objective (default), 2: deltaq placeholder, 3: key frame visual quality, 4: user rating based visual quality optimization); requires \fB\-\-enable\-tpl\-model\fR=\fI\,1\/\fR
\fB\-\-deltaq\-strength=\fR<arg>     Deltaq strength for \fB\-\-deltaq\-mode\fR=\fI\,4\/\fR (%)
\fB\-\-delta\-lf\-mode=\fR<arg>       Enable delta\-lf\-mode (0: off (default), 1: on)
\fB\-\-frame\-boost=\fR<arg>         Enable frame periodic boost (0: off (default), 1: on)
\fB\-\-noise\-sensitivity=\fR<arg>   Noise sensitivity (frames to blur)
\fB\-\-tune\-content=\fR<arg>        Tune content type
.IP
default, screen, film
.TP
\fB\-\-cdf\-update\-mode=\fR<arg>
CDF update mode for entropy coding (0: no CDF update, 1: update CDF on all frames (default), 2: selectively update CDF on some frames)
.TP
\fB\-\-color\-primaries=\fR<arg>
Color primaries (CICP) of input content:
.IP
bt709, unspecified, bt601, bt470m, bt470bg, smpte240, film, bt2020, xyz, smpte431, smpte432, ebu3213
.TP
\fB\-\-transfer\-characteristics=\fR<arg>
Transfer characteristics (CICP) of input content:
.IP
unspecified, bt709, bt470m, bt470bg, bt601, smpte240, lin, log100, log100sq10, iec61966, bt1361, srgb, bt2020\-10bit, bt2020\-12bit, smpte2084, hlg, smpte428
.TP
\fB\-\-matrix\-coefficients=\fR<arg> Matrix coefficients (CICP) of input content:
identity, bt709, unspecified, fcc73, bt470bg, bt601, smpte240, ycgco, bt2020ncl, bt2020cl, smpte2085, chromncl, chromcl, ictcp
.TP
\fB\-\-chroma\-sample\-position=\fR<arg>
The chroma sample position when chroma 4:2:0 is signaled:
.IP
unknown, vertical, colocated
.TP
\fB\-\-min\-gf\-interval=\fR<arg>
Min gf/arf frame interval (default 0, indicating in\-built behavior)
.TP
\fB\-\-max\-gf\-interval=\fR<arg>
Max gf/arf frame interval (default 0, indicating in\-built behavior)
.TP
\fB\-\-gf\-min\-pyr\-height=\fR<arg>
Min height for GF group pyramid structure (0 (default) to 5)
.TP
\fB\-\-gf\-max\-pyr\-height=\fR<arg>
Maximum height for GF group pyramid structure (0 to 5 (default))
.TP
\fB\-\-sb\-size=\fR<arg>
Superblock size to use
.IP
dynamic, 64, 128
.TP
\fB\-\-num\-tile\-groups=\fR<arg>
Maximum number of tile groups, default is 1
.TP
\fB\-\-mtu\-size=\fR<arg>
MTU size for a tile group, default is 0 (no MTU targeting), overrides maximum number of tile groups
.TP
\fB\-\-timing\-info=\fR<arg>
Signal timing info in the bitstream (model only works for no hidden frames, no super\-res yet):
.IP
unspecified, constant, model
.TP
\fB\-\-film\-grain\-test=\fR<arg>
Film grain test vectors (0: none (default), 1: test\-1  2: test\-2, ... 16: test\-16)
.TP
\fB\-\-film\-grain\-table=\fR<arg>
Path to file containing film grain parameters
.IP
\fB\-\-denoise\-noise\-level=\fR<arg> Amount of noise (from 0 = don't denoise, to 50)
\fB\-\-denoise\-block\-size=\fR<arg>  Denoise block size (default = 32)
\fB\-\-enable\-dnl\-denoising=\fR<arg>
.IP
Apply denoising to the frame being encoded when denoise\-noise\-level is enabled (0: false, 1: true (default))
.TP
\fB\-\-max\-reference\-frames=\fR<arg>
Maximum number of reference frames allowed per frame (3 to 7 (default))
.TP
\fB\-\-reduced\-reference\-set=\fR<arg>
Use reduced set of single and compound references (0: off (default), 1: on)
.TP
\fB\-\-enable\-ref\-frame\-mvs=\fR<arg>
Enable temporal mv prediction (default is 1)
.TP
\fB\-\-target\-seq\-level\-idx=\fR<arg>
Target sequence level index. Possible values are in the form of "ABxy". AB: Operating point (OP) index, xy: Target level index for the OP. E.g. "0" means target level index 0 (2.0) for the 0th OP, "1019" means target level index 19 (6.3) for the 10th OP.
.TP
\fB\-\-set\-tier\-mask=\fR<arg>
Set bit mask to specify which tier each of the 32 possible operating points conforms to. Bit value 0 (default): Main Tier, 1: High Tier.
.TP
\fB\-\-min\-cr=\fR<arg>
Set minimum compression ratio. Take integer values. Default is 0. If non\-zero, encoder will try to keep the compression ratio of each frame to be higher than the given value divided by 100.
.TP
\fB\-\-vbr\-corpus\-complexity\-lap=\fR<arg>
Set average corpus complexity per mb for single pass VBR using lap. (0..10000), default is 0
.TP
\fB\-\-input\-chroma\-subsampling\-x=\fR<arg>
Chroma subsampling x value
.TP
\fB\-\-input\-chroma\-subsampling\-y=\fR<arg>
Chroma subsampling y value
.TP
\fB\-\-dv\-cost\-upd\-freq=\fR<arg>
Update freq for dv costs. 0: SB, 1: SB Row per Tile, 2: Tile, 3: Off
.IP
\fB\-\-partition\-info\-path=\fR<arg> Partition information read and write path
\fB\-\-enable\-directional\-intra=\fR<arg>
.IP
Enable directional intra prediction modes (0: false, 1: true (default))
.TP
\fB\-\-enable\-tx\-size\-search=\fR<arg>
Enable transform size search to find the best size for each block. If false, transforms always have the largest possible size (0: false, 1: true (default)). Ignored in non rd pick mode in real\-time coding.
.TP
\fB\-\-loopfilter\-control=\fR<arg>
Control loop filtering (0: Loopfilter disabled for all frames, 1: Enable loopfilter for all frames (default), 2: Disable loopfilter for non\-reference frames, 3: Disable loopfilter for frames with low motion)
.TP
\fB\-\-auto\-intra\-tools\-off=\fR<arg>
Automatically turn off several intra coding tools for allintra mode; only in effect if \fB\-\-deltaq\-mode\fR=\fI\,3\/\fR
.TP
\fB\-p\fR <arg>, \fB\-\-passes=\fR<arg>
Number of passes (1/2/3)
.TP
\fB\-\-two\-pass\-output=\fR<arg>
The output file for the first two passes for three\-pass encoding
.TP
\fB\-spf\fR <arg>, \fB\-\-second\-pass\-log=\fR<arg>
Log file from second pass
.TP
\fB\-\-fwd\-kf\-dist=\fR<arg>
Set distance between forward keyframes. A value of \fB\-1\fR (default) means no repetitive forward keyframes.
.TP
\fB\-\-strict\-level\-conformance=\fR<arg>
When set to 1, exit the encoder when it fails to encode to a given target level
.TP
\fB\-\-dist\-metric=\fR<arg>
Distortion metric to use for in\-block optimization
.IP
psnr, qm\-psnr
.SS "Stream timebase (--timebase):"
.IP
The desired precision of timestamps in the output, expressed
in fractional seconds. Default is 1/1000.
.PP
Included encoders:
.TP
av1
\- AOMedia Project AV1 Encoder v3.5.0 (default)
.IP
Use \fB\-\-codec\fR to switch to a non\-default encoder.