| Name | Description | Required | Value | Default |
| id | the codec id for the target format.
| Yes | VideoCodecs | none |
| b | set bitrate (in bits/s) | Yes | int | 0 |
| bt | set video bitrate tolerance (in bits/s) | No | int | 0 |
| mv4 | use four motion vector by macroblock | No | Bool | false |
| obmc | use overlapped block motion compensation (h263+) | No | Bool | false |
| qpel | use 1/4 pel motion compensation | No | Bool | false |
| loop | use loop filter | No | Bool | false |
| gmc | use gmc | No | Bool | false |
| mv0 | always try a mb with mv=<0,0> | No | Bool | false |
| part | use data partitioning | No | Bool | false |
| gray | only decode/encode grayscale | No | Bool | false |
| naq | normalize adaptive quantization | No | Bool | false |
| ildct | use interlaced dct | No | Bool | false |
| low_delay | force low delay | No | Bool | false |
| alt | enable alternate scantable (mpeg2/mpeg4) | No | Bool | false |
| global_header | place global headers in extradata instead of every keyframe | No | Bool | false |
| bitexact | use only bitexact stuff (except (i)dct) | No | Bool | false |
| aic | h263 advanced intra coding / mpeg4 ac prediction | No | Bool | false |
| umv | use unlimited motion vectors | No | Bool | false |
| cbp | use rate distortion optimization for cbp | No | Bool | false |
| qprd | use rate distortion optimization for qp selection | No | Bool | false |
| aiv | h263 alternative inter vlc | No | Bool | false |
| slice | | No | Bool | false |
| ilme | interlaced motion estimation | No | Bool | false |
| scan_offset | will reserve space for svcd scan offset user data | No | Bool | false |
| cgop | closed gop | No | Bool | false |
| me_method | set motion estimation method | No | MeMethod | epzs |
| g | set the group of picture size | | | |
| cutoff | set cutoff bandwidth | | | |
| frame_size | | | | |
| qcomp | video quantizer scale compression (VBR) | | | |
| qblur | video quantizer scale blur (VBR) | | | |
| qmin | min video quantizer scale (VBR) | | | |
| qmax | max video quantizer scale (VBR) | | | |
| qdiff | max difference between the quantizer scale (VBR) | | | |
| bf | use 'frames' B frames | | | |
| b_qfactor | qp factor between p and b frames | | | |
| rc_strategy | ratecontrol method | | | |
| b_strategy | strategy to choose between I/P/B-frames | | | |
| wpredp | weighted prediction analysis method | | | |
| ps | rtp payload size in bytes | | | |
| lelim | single coefficient elimination threshold for luminance (negative values also consider dc coefficient) | | | |
| celim | single coefficient elimination threshold for chrominance (negative values also consider dc coefficient) | | | |
| strict | how strictly to follow the standards | | Strict | |
| b_qoffset | qp offset between P and B frames | | | |
| mpeg_quant | use MPEG quantizers instead of H.263 | | | |
| qsquish | how to keep quantizer between qmin and qmax (0 = clip, 1 = use differentiable function) | | | |
| rc_qmod_amp | experimental quantizer modulation | | | |
| rc_qmod_freq | experimental quantizer modulation | | | |
| rc_eq | set rate control equation | | | |
| maxrate | set max video bitrate tolerance (in bits/s) | | | |
| minrate | set min video bitrate tolerance (in bits/s) | | | |
| bufsize | set ratecontrol buffer size (in bits) | | | |
| rc_buf_aggressivity | currently useless | | | |
| i_qfactor | qp factor between P and I frames | | | |
| i_qoffset | qp offset between P and I frames | | | |
| rc_init_cplx | initial complexity for 1-pass encoding | | | |
| dct | DCT algorithm | | Dct | |
| lumi_mask | compresses bright areas stronger than medium ones | | | |
| tcplx_mask | temporal complexity masking | | | |
| scplx_mask | spatial complexity masking | | | |
| p_mask | inter masking | | | |
| dark_mask | compresses dark areas stronger than medium ones | | | |
| idct | select IDCT implementation | | IDct | |
| pred | prediction method | | Pred | |
| aspect | sample aspect ratio | | Rational | |
| cmp | full pel me compare function | | CmpFunctions | |
| subcmp | sub pel me compare function | | CmpFunctions | |
| mbcmp | macroblock compare function | | CmpFunctions | |
| ildctcmp | interlaced dct compare function | | CmpFunctions | |
| dia_size | diamond type & size for motion estimation | | | |
| last_pred | amount of motion predictors from the previous frame | | | |
| preme | pre motion estimation | | | |
| precmp | pre motion estimation compare function | | CmpFunctions | |
| pre_dia_size | diamond type & size for motion estimation pre-pass | | | |
| subq | sub pel motion estimation quality | | | |
| me_range | limit motion vectors range (1023 for DivX player) | | | |
| ibias | intra quant bias | | | |
| pbias | inter quant bias | | | |
| coder | | | Coder | |
| context | context model | | | |
| mbd | macroblock decision algorithm (high quality mode) | | MBD | |
| sc_threshold | scene change threshold | | | |
| lmin | min lagrange factor (VBR) | | | |
| lmax | max lagrange factor (VBR) | | | |
| nr | noise reduction | | | |
| rc_init_occupancy | number of bits which should be loaded into the rc buffer before decoding starts | | | |
| inter_threshold | | | | |
| fast | allow non spec compliant speedup tricks | | Bool | |
| sgop | strictly enforce gop size | | Bool | |
| noout | skip bitstream encoding | | Bool | |
| local_header | place global headers at every keyframe instead of in extradata | | Bool | |
| bpyramid | allows B-frames to be used as references for predicting | | Bool | |
| wpred | weighted biprediction for b-frames (H.264) | | Bool | |
| mixed_refs | one reference per partition, as opposed to one reference per macroblock | | Bool | |
| dct8x8 | high profile 8x8 transform (H.264) | | Bool | |
| fastpskip | fast pskip (H.264) | | Bool | |
| aud | access unit delimiters (H.264) | | Bool | |
| skiprd | RD optimal MB level residual skipping | | Bool | |
| ivlc | intra vlc table | | Bool | |
| drop_frame_timecode | | | Bool | |
| non_linear_q | use non linear quantizer | | Bool | |
| reservoir | use bit reservoir | | Bool | |
| mbtree | use macroblock tree ratecontrol (x264 only) | | Bool | |
| psy | use psycho visual optimization | | Bool | |
| intra_refresh | use periodic insertion of intra blocks instead of keyframes | | Bool | |
| error | | | | |
| qns | quantizer noise shaping | | | |
| mb_threshold | macroblock threshold | | | |
| dc | intra_dc_precision | | | |
| nssew | nsse weight | | | |
| profile | | | | |
| level | | | | |
| skip_threshold | frame skip threshold | | | |
| skip_factor | frame skip factor | | | |
| skip_exp | frame skip exponent | | | |
| skipcmp | frame skip compare function | | CmpFunctions | |
| border_mask | increases the quantizer for macroblocks close to borders | | | |
| mblmin | min macroblock lagrange factor (VBR) | | | |
| mblmax | max macroblock lagrange factor (VBR) | | | |
| mepc | motion estimation bitrate penalty compensation (1.0 = 256) | | | |
| bidir_refine | refine the two motion vectors used in bidirectional macroblocks | | | |
| brd_scale | downscales frames for dynamic B-frame decision | | | |
| crf | enables constant quality mode, and selects the quality (x264/VP8) | | | |
| cqp | constant quantization parameter rate control method | | | |
| keyint_min | minimum interval between IDR-frames | | | |
| refs | reference frames to consider for motion compensation | | | |
| chromaoffset | chroma qp offset from luma | | | |
| bframebias | influences how often B-frames are used | | | |
| trellis | rate-distortion optimal quantization | | | |
| directpred | direct mv prediction mode - 0 (none), 1 (spatial), 2 (temporal), 3 (auto) | | | |
| complexityblur | reduce fluctuations in qp (before curve compression) | | | |
| deblockalpha | in-loop deblocking filter alphac0 parameter | | | |
| deblockbeta | in-loop deblocking filter beta parameter | | | |
| partitions | macroblock subpartition sizes to consider | | Partitions | |
| sc_factor | multiplied by qscale for each frame and added to scene_change_score | | | |
| mv0_threshold | | | | |
| b_sensitivity | adjusts sensitivity of b_frame_strategy 1 | | | |
| compression_level | | | | |
| timecode_frame_start | GOP timecode frame start number, in non drop frame format | | | |
| rc_max_vbv_use | | | | |
| rc_min_vbv_use | | | | |
| ticks_per_frame | | | | |
| color_primaries | | | | |
| color_trc | | | | |
| colorspace | | | | |
| color_range | | | | |
| chroma_sample_location | | | | |
| psy_rd | specify psycho visual strength | | | |
| psy_trellis | specify psycho visual trellis | | | |
| aq_mode | specify aq method | | | |
| aq_strength | specify aq strength | | | |
| rc_lookahead | specify number of frames to look ahead for frametype | | | |
| crf_max | in crf mode, prevents vbv from lowering quality beyond this point | | | |
| nitris_compat | encode with Avid Nitris compatibility | | | |
| resize_fnct | scaler/cpu flags | | ResizeFunctions | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |