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1@anchor{codec-options}
2@chapter Codec Options
3@c man begin CODEC OPTIONS
4
5libavcodec provides some generic global options, which can be set on
6all the encoders and decoders. In addition each codec may support
7so-called private options, which are specific for a given codec.
8
9Sometimes, a global option may only affect a specific kind of codec,
10and may be unsensical or ignored by another, so you need to be aware
11of the meaning of the specified options. Also some options are
12meant only for decoding or encoding.
13
14Options may be set by specifying -@var{option} @var{value} in the
15FFmpeg tools, or by setting the value explicitly in the
16@code{AVCodecContext} options or using the @file{libavutil/opt.h} API
17for programmatic use.
18
19The list of supported options follow:
20
21@table @option
22@item b @var{integer} (@emph{encoding,audio,video})
23Set bitrate in bits/s. Default value is 200K.
24
25@item ab @var{integer} (@emph{encoding,audio})
26Set audio bitrate (in bits/s). Default value is 128K.
27
28@item bt @var{integer} (@emph{encoding,video})
29Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate
30tolerance specifies how far ratecontrol is willing to deviate from the
31target average bitrate value. This is not related to min/max
32bitrate. Lowering tolerance too much has an adverse effect on quality.
33
34@item flags @var{flags} (@emph{decoding/encoding,audio,video,subtitles})
35Set generic flags.
36
37Possible values:
38@table @samp
39@item mv4
40Use four motion vector by macroblock (mpeg4).
41@item qpel
42Use 1/4 pel motion compensation.
43@item loop
44Use loop filter.
45@item qscale
46Use fixed qscale.
47@item gmc
48Use gmc.
49@item mv0
50Always try a mb with mv=<0,0>.
51@item input_preserved
52
53@item pass1
54Use internal 2pass ratecontrol in first pass mode.
55@item pass2
56Use internal 2pass ratecontrol in second pass mode.
57@item gray
58Only decode/encode grayscale.
59@item emu_edge
60Do not draw edges.
61@item psnr
62Set error[?] variables during encoding.
63@item truncated
64
65@item naq
66Normalize adaptive quantization.
67@item ildct
68Use interlaced DCT.
69@item low_delay
70Force low delay.
71@item global_header
72Place global headers in extradata instead of every keyframe.
73@item bitexact
74Use only bitexact stuff (except (I)DCT).
75@item aic
76Apply H263 advanced intra coding / mpeg4 ac prediction.
77@item cbp
78Deprecated, use mpegvideo private options instead.
79@item qprd
80Deprecated, use mpegvideo private options instead.
81@item ilme
82Apply interlaced motion estimation.
83@item cgop
84Use closed gop.
85@end table
86
87@item me_method @var{integer} (@emph{encoding,video})
88Set motion estimation method.
89
90Possible values:
91@table @samp
92@item zero
93zero motion estimation (fastest)
94@item full
95full motion estimation (slowest)
96@item epzs
97EPZS motion estimation (default)
98@item esa
99esa motion estimation (alias for full)
100@item tesa
101tesa motion estimation
102@item dia
103dia motion estimation (alias for epzs)
104@item log
105log motion estimation
106@item phods
107phods motion estimation
108@item x1
109X1 motion estimation
110@item hex
111hex motion estimation
112@item umh
113umh motion estimation
114@item iter
115iter motion estimation
116@end table
117
118@item extradata_size @var{integer}
119Set extradata size.
120
121@item time_base @var{rational number}
122Set codec time base.
123
124It is the fundamental unit of time (in seconds) in terms of which
125frame timestamps are represented. For fixed-fps content, timebase
126should be @code{1 / frame_rate} and timestamp increments should be
127identically 1.
128
129@item g @var{integer} (@emph{encoding,video})
130Set the group of picture size. Default value is 12.
131
132@item ar @var{integer} (@emph{decoding/encoding,audio})
133Set audio sampling rate (in Hz).
134
135@item ac @var{integer} (@emph{decoding/encoding,audio})
136Set number of audio channels.
137
138@item cutoff @var{integer} (@emph{encoding,audio})
139Set cutoff bandwidth.
140
141@item frame_size @var{integer} (@emph{encoding,audio})
142Set audio frame size.
143
144Each submitted frame except the last must contain exactly frame_size
145samples per channel. May be 0 when the codec has
146CODEC_CAP_VARIABLE_FRAME_SIZE set, in that case the frame size is not
147restricted. It is set by some decoders to indicate constant frame
148size.
149
150@item frame_number @var{integer}
151Set the frame number.
152
153@item delay @var{integer}
154
155@item qcomp @var{float} (@emph{encoding,video})
156Set video quantizer scale compression (VBR). It is used as a constant
157in the ratecontrol equation. Recommended range for default rc_eq:
1580.0-1.0.
159
160@item qblur @var{float} (@emph{encoding,video})
161Set video quantizer scale blur (VBR).
162
163@item qmin @var{integer} (@emph{encoding,video})
164Set min video quantizer scale (VBR). Must be included between -1 and
16569, default value is 2.
166
167@item qmax @var{integer} (@emph{encoding,video})
168Set max video quantizer scale (VBR). Must be included between -1 and
1691024, default value is 31.
170
171@item qdiff @var{integer} (@emph{encoding,video})
172Set max difference between the quantizer scale (VBR).
173
174@item bf @var{integer} (@emph{encoding,video})
175Set max number of B frames between non-B-frames.
176
177Must be an integer between -1 and 16. 0 means that B-frames are
178disabled. If a value of -1 is used, it will choose an automatic value
179depending on the encoder.
180
181Default value is 0.
182
183@item b_qfactor @var{float} (@emph{encoding,video})
184Set qp factor between P and B frames.
185
186@item rc_strategy @var{integer} (@emph{encoding,video})
187Set ratecontrol method.
188
189@item b_strategy @var{integer} (@emph{encoding,video})
190Set strategy to choose between I/P/B-frames.
191
192@item ps @var{integer} (@emph{encoding,video})
193Set RTP payload size in bytes.
194
195@item mv_bits @var{integer}
196@item header_bits @var{integer}
197@item i_tex_bits @var{integer}
198@item p_tex_bits @var{integer}
199@item i_count @var{integer}
200@item p_count @var{integer}
201@item skip_count @var{integer}
202@item misc_bits @var{integer}
203@item frame_bits @var{integer}
204@item codec_tag @var{integer}
205@item bug @var{flags} (@emph{decoding,video})
206Workaround not auto detected encoder bugs.
207
208Possible values:
209@table @samp
210@item autodetect
211
212@item old_msmpeg4
213some old lavc generated msmpeg4v3 files (no autodetection)
214@item xvid_ilace
215Xvid interlacing bug (autodetected if fourcc==XVIX)
216@item ump4
217(autodetected if fourcc==UMP4)
218@item no_padding
219padding bug (autodetected)
220@item amv
221
222@item ac_vlc
223illegal vlc bug (autodetected per fourcc)
224@item qpel_chroma
225
226@item std_qpel
227old standard qpel (autodetected per fourcc/version)
228@item qpel_chroma2
229
230@item direct_blocksize
231direct-qpel-blocksize bug (autodetected per fourcc/version)
232@item edge
233edge padding bug (autodetected per fourcc/version)
234@item hpel_chroma
235
236@item dc_clip
237
238@item ms
239Workaround various bugs in microsoft broken decoders.
240@item trunc
241trancated frames
242@end table
243
244@item lelim @var{integer} (@emph{encoding,video})
245Set single coefficient elimination threshold for luminance (negative
246values also consider DC coefficient).
247
248@item celim @var{integer} (@emph{encoding,video})
249Set single coefficient elimination threshold for chrominance (negative
250values also consider dc coefficient)
251
252@item strict @var{integer} (@emph{decoding/encoding,audio,video})
253Specify how strictly to follow the standards.
254
255Possible values:
256@table @samp
257@item very
258strictly conform to a older more strict version of the spec or reference software
259@item strict
260strictly conform to all the things in the spec no matter what consequences
261@item normal
262
263@item unofficial
264allow unofficial extensions
265@item experimental
266allow non standardized experimental things, experimental
267(unfinished/work in progress/not well tested) decoders and encoders.
268Note: experimental decoders can pose a security risk, do not use this for
269decoding untrusted input.
270@end table
271
272@item b_qoffset @var{float} (@emph{encoding,video})
273Set QP offset between P and B frames.
274
275@item err_detect @var{flags} (@emph{decoding,audio,video})
276Set error detection flags.
277
278Possible values:
279@table @samp
280@item crccheck
281verify embedded CRCs
282@item bitstream
283detect bitstream specification deviations
284@item buffer
285detect improper bitstream length
286@item explode
287abort decoding on minor error detection
288@item careful
289consider things that violate the spec and have not been seen in the wild as errors
290@item compliant
291consider all spec non compliancies as errors
292@item aggressive
293consider things that a sane encoder should not do as an error
294@end table
295
296@item has_b_frames @var{integer}
297
298@item block_align @var{integer}
299
300@item mpeg_quant @var{integer} (@emph{encoding,video})
301Use MPEG quantizers instead of H.263.
302
303@item qsquish @var{float} (@emph{encoding,video})
304How to keep quantizer between qmin and qmax (0 = clip, 1 = use
305differentiable function).
306
307@item rc_qmod_amp @var{float} (@emph{encoding,video})
308Set experimental quantizer modulation.
309
310@item rc_qmod_freq @var{integer} (@emph{encoding,video})
311Set experimental quantizer modulation.
312
313@item rc_override_count @var{integer}
314
315@item rc_eq @var{string} (@emph{encoding,video})
316Set rate control equation. When computing the expression, besides the
317standard functions defined in the section 'Expression Evaluation', the
318following functions are available: bits2qp(bits), qp2bits(qp). Also
319the following constants are available: iTex pTex tex mv fCode iCount
320mcVar var isI isP isB avgQP qComp avgIITex avgPITex avgPPTex avgBPTex
321avgTex.
322
323@item maxrate @var{integer} (@emph{encoding,audio,video})
324Set max bitrate tolerance (in bits/s). Requires bufsize to be set.
325
326@item minrate @var{integer} (@emph{encoding,audio,video})
327Set min bitrate tolerance (in bits/s). Most useful in setting up a CBR
328encode. It is of little use elsewise.
329
330@item bufsize @var{integer} (@emph{encoding,audio,video})
331Set ratecontrol buffer size (in bits).
332
333@item rc_buf_aggressivity @var{float} (@emph{encoding,video})
334Currently useless.
335
336@item i_qfactor @var{float} (@emph{encoding,video})
337Set QP factor between P and I frames.
338
339@item i_qoffset @var{float} (@emph{encoding,video})
340Set QP offset between P and I frames.
341
342@item rc_init_cplx @var{float} (@emph{encoding,video})
343Set initial complexity for 1-pass encoding.
344
345@item dct @var{integer} (@emph{encoding,video})
346Set DCT algorithm.
347
348Possible values:
349@table @samp
350@item auto
351autoselect a good one (default)
352@item fastint
353fast integer
354@item int
355accurate integer
356@item mmx
357
358@item altivec
359
360@item faan
361floating point AAN DCT
362@end table
363
364@item lumi_mask @var{float} (@emph{encoding,video})
365Compress bright areas stronger than medium ones.
366
367@item tcplx_mask @var{float} (@emph{encoding,video})
368Set temporal complexity masking.
369
370@item scplx_mask @var{float} (@emph{encoding,video})
371Set spatial complexity masking.
372
373@item p_mask @var{float} (@emph{encoding,video})
374Set inter masking.
375
376@item dark_mask @var{float} (@emph{encoding,video})
377Compress dark areas stronger than medium ones.
378
379@item idct @var{integer} (@emph{decoding/encoding,video})
380Select IDCT implementation.
381
382Possible values:
383@table @samp
384@item auto
385
386@item int
387
388@item simple
389
390@item simplemmx
391
392@item arm
393
394@item altivec
395
396@item sh4
397
398@item simplearm
399
400@item simplearmv5te
401
402@item simplearmv6
403
404@item simpleneon
405
406@item simplealpha
407
408@item ipp
409
410@item xvidmmx
411
412@item faani
413floating point AAN IDCT
414@end table
415
416@item slice_count @var{integer}
417
418@item ec @var{flags} (@emph{decoding,video})
419Set error concealment strategy.
420
421Possible values:
422@table @samp
423@item guess_mvs
424iterative motion vector (MV) search (slow)
425@item deblock
426use strong deblock filter for damaged MBs
427@end table
428
429@item bits_per_coded_sample @var{integer}
430
431@item pred @var{integer} (@emph{encoding,video})
432Set prediction method.
433
434Possible values:
435@table @samp
436@item left
437
438@item plane
439
440@item median
441
442@end table
443
444@item aspect @var{rational number} (@emph{encoding,video})
445Set sample aspect ratio.
446
447@item debug @var{flags} (@emph{decoding/encoding,audio,video,subtitles})
448Print specific debug info.
449
450Possible values:
451@table @samp
452@item pict
453picture info
454@item rc
455rate control
456@item bitstream
457
458@item mb_type
459macroblock (MB) type
460@item qp
461per-block quantization parameter (QP)
462@item mv
463motion vector
464@item dct_coeff
465
466@item skip
467
468@item startcode
469
470@item pts
471
472@item er
473error recognition
474@item mmco
475memory management control operations (H.264)
476@item bugs
477
478@item vis_qp
479visualize quantization parameter (QP), lower QP are tinted greener
480@item vis_mb_type
481visualize block types
482@item buffers
483picture buffer allocations
484@item thread_ops
485threading operations
486@end table
487
488@item vismv @var{integer} (@emph{decoding,video})
489Visualize motion vectors (MVs).
490
491Possible values:
492@table @samp
493@item pf
494forward predicted MVs of P-frames
495@item bf
496forward predicted MVs of B-frames
497@item bb
498backward predicted MVs of B-frames
499@end table
500
501@item cmp @var{integer} (@emph{encoding,video})
502Set full pel me compare function.
503
504Possible values:
505@table @samp
506@item sad
507sum of absolute differences, fast (default)
508@item sse
509sum of squared errors
510@item satd
511sum of absolute Hadamard transformed differences
512@item dct
513sum of absolute DCT transformed differences
514@item psnr
515sum of squared quantization errors (avoid, low quality)
516@item bit
517number of bits needed for the block
518@item rd
519rate distortion optimal, slow
520@item zero
5210
522@item vsad
523sum of absolute vertical differences
524@item vsse
525sum of squared vertical differences
526@item nsse
527noise preserving sum of squared differences
528@item w53
5295/3 wavelet, only used in snow
530@item w97
5319/7 wavelet, only used in snow
532@item dctmax
533
534@item chroma
535
536@end table
537
538@item subcmp @var{integer} (@emph{encoding,video})
539Set sub pel me compare function.
540
541Possible values:
542@table @samp
543@item sad
544sum of absolute differences, fast (default)
545@item sse
546sum of squared errors
547@item satd
548sum of absolute Hadamard transformed differences
549@item dct
550sum of absolute DCT transformed differences
551@item psnr
552sum of squared quantization errors (avoid, low quality)
553@item bit
554number of bits needed for the block
555@item rd
556rate distortion optimal, slow
557@item zero
5580
559@item vsad
560sum of absolute vertical differences
561@item vsse
562sum of squared vertical differences
563@item nsse
564noise preserving sum of squared differences
565@item w53
5665/3 wavelet, only used in snow
567@item w97
5689/7 wavelet, only used in snow
569@item dctmax
570
571@item chroma
572
573@end table
574
575@item mbcmp @var{integer} (@emph{encoding,video})
576Set macroblock compare function.
577
578Possible values:
579@table @samp
580@item sad
581sum of absolute differences, fast (default)
582@item sse
583sum of squared errors
584@item satd
585sum of absolute Hadamard transformed differences
586@item dct
587sum of absolute DCT transformed differences
588@item psnr
589sum of squared quantization errors (avoid, low quality)
590@item bit
591number of bits needed for the block
592@item rd
593rate distortion optimal, slow
594@item zero
5950
596@item vsad
597sum of absolute vertical differences
598@item vsse
599sum of squared vertical differences
600@item nsse
601noise preserving sum of squared differences
602@item w53
6035/3 wavelet, only used in snow
604@item w97
6059/7 wavelet, only used in snow
606@item dctmax
607
608@item chroma
609
610@end table
611
612@item ildctcmp @var{integer} (@emph{encoding,video})
613Set interlaced dct compare function.
614
615Possible values:
616@table @samp
617@item sad
618sum of absolute differences, fast (default)
619@item sse
620sum of squared errors
621@item satd
622sum of absolute Hadamard transformed differences
623@item dct
624sum of absolute DCT transformed differences
625@item psnr
626sum of squared quantization errors (avoid, low quality)
627@item bit
628number of bits needed for the block
629@item rd
630rate distortion optimal, slow
631@item zero
6320
633@item vsad
634sum of absolute vertical differences
635@item vsse
636sum of squared vertical differences
637@item nsse
638noise preserving sum of squared differences
639@item w53
6405/3 wavelet, only used in snow
641@item w97
6429/7 wavelet, only used in snow
643@item dctmax
644
645@item chroma
646
647@end table
648
649@item dia_size @var{integer} (@emph{encoding,video})
650Set diamond type & size for motion estimation.
651
652@item last_pred @var{integer} (@emph{encoding,video})
653Set amount of motion predictors from the previous frame.
654
655@item preme @var{integer} (@emph{encoding,video})
656Set pre motion estimation.
657
658@item precmp @var{integer} (@emph{encoding,video})
659Set pre motion estimation compare function.
660
661Possible values:
662@table @samp
663@item sad
664sum of absolute differences, fast (default)
665@item sse
666sum of squared errors
667@item satd
668sum of absolute Hadamard transformed differences
669@item dct
670sum of absolute DCT transformed differences
671@item psnr
672sum of squared quantization errors (avoid, low quality)
673@item bit
674number of bits needed for the block
675@item rd
676rate distortion optimal, slow
677@item zero
6780
679@item vsad
680sum of absolute vertical differences
681@item vsse
682sum of squared vertical differences
683@item nsse
684noise preserving sum of squared differences
685@item w53
6865/3 wavelet, only used in snow
687@item w97
6889/7 wavelet, only used in snow
689@item dctmax
690
691@item chroma
692
693@end table
694
695@item pre_dia_size @var{integer} (@emph{encoding,video})
696Set diamond type & size for motion estimation pre-pass.
697
698@item subq @var{integer} (@emph{encoding,video})
699Set sub pel motion estimation quality.
700
701@item dtg_active_format @var{integer}
702
703@item me_range @var{integer} (@emph{encoding,video})
704Set limit motion vectors range (1023 for DivX player).
705
706@item ibias @var{integer} (@emph{encoding,video})
707Set intra quant bias.
708
709@item pbias @var{integer} (@emph{encoding,video})
710Set inter quant bias.
711
712@item color_table_id @var{integer}
713
714@item global_quality @var{integer} (@emph{encoding,audio,video})
715
716@item coder @var{integer} (@emph{encoding,video})
717
718Possible values:
719@table @samp
720@item vlc
721variable length coder / huffman coder
722@item ac
723arithmetic coder
724@item raw
725raw (no encoding)
726@item rle
727run-length coder
728@item deflate
729deflate-based coder
730@end table
731
732@item context @var{integer} (@emph{encoding,video})
733Set context model.
734
735@item slice_flags @var{integer}
736
737@item xvmc_acceleration @var{integer}
738
739@item mbd @var{integer} (@emph{encoding,video})
740Set macroblock decision algorithm (high quality mode).
741
742Possible values:
743@table @samp
744@item simple
745use mbcmp (default)
746@item bits
747use fewest bits
748@item rd
749use best rate distortion
750@end table
751
752@item stream_codec_tag @var{integer}
753
754@item sc_threshold @var{integer} (@emph{encoding,video})
755Set scene change threshold.
756
757@item lmin @var{integer} (@emph{encoding,video})
758Set min lagrange factor (VBR).
759
760@item lmax @var{integer} (@emph{encoding,video})
761Set max lagrange factor (VBR).
762
763@item nr @var{integer} (@emph{encoding,video})
764Set noise reduction.
765
766@item rc_init_occupancy @var{integer} (@emph{encoding,video})
767Set number of bits which should be loaded into the rc buffer before
768decoding starts.
769
770@item flags2 @var{flags} (@emph{decoding/encoding,audio,video})
771
772Possible values:
773@table @samp
774@item fast
775Allow non spec compliant speedup tricks.
776@item sgop
777Deprecated, use mpegvideo private options instead.
778@item noout
779Skip bitstream encoding.
780@item ignorecrop
781Ignore cropping information from sps.
782@item local_header
783Place global headers at every keyframe instead of in extradata.
784@item chunks
785Frame data might be split into multiple chunks.
786@item showall
787Show all frames before the first keyframe.
788@item skiprd
789Deprecated, use mpegvideo private options instead.
790@end table
791
792@item error @var{integer} (@emph{encoding,video})
793
794@item qns @var{integer} (@emph{encoding,video})
795Deprecated, use mpegvideo private options instead.
796
797@item threads @var{integer} (@emph{decoding/encoding,video})
798
799Possible values:
800@table @samp
801@item auto
802detect a good number of threads
803@end table
804
805@item me_threshold @var{integer} (@emph{encoding,video})
806Set motion estimation threshold.
807
808@item mb_threshold @var{integer} (@emph{encoding,video})
809Set macroblock threshold.
810
811@item dc @var{integer} (@emph{encoding,video})
812Set intra_dc_precision.
813
814@item nssew @var{integer} (@emph{encoding,video})
815Set nsse weight.
816
817@item skip_top @var{integer} (@emph{decoding,video})
818Set number of macroblock rows at the top which are skipped.
819
820@item skip_bottom @var{integer} (@emph{decoding,video})
821Set number of macroblock rows at the bottom which are skipped.
822
823@item profile @var{integer} (@emph{encoding,audio,video})
824
825Possible values:
826@table @samp
827@item unknown
828
829@item aac_main
830
831@item aac_low
832
833@item aac_ssr
834
835@item aac_ltp
836
837@item aac_he
838
839@item aac_he_v2
840
841@item aac_ld
842
843@item aac_eld
844
845@item mpeg2_aac_low
846
847@item mpeg2_aac_he
848
849@item dts
850
851@item dts_es
852
853@item dts_96_24
854
855@item dts_hd_hra
856
857@item dts_hd_ma
858
859@end table
860
861@item level @var{integer} (@emph{encoding,audio,video})
862
863Possible values:
864@table @samp
865@item unknown
866
867@end table
868
869@item lowres @var{integer} (@emph{decoding,audio,video})
870Decode at 1= 1/2, 2=1/4, 3=1/8 resolutions.
871
872@item skip_threshold @var{integer} (@emph{encoding,video})
873Set frame skip threshold.
874
875@item skip_factor @var{integer} (@emph{encoding,video})
876Set frame skip factor.
877
878@item skip_exp @var{integer} (@emph{encoding,video})
879Set frame skip exponent.
880
881@item skipcmp @var{integer} (@emph{encoding,video})
882Set frame skip compare function.
883
884Possible values:
885@table @samp
886@item sad
887sum of absolute differences, fast (default)
888@item sse
889sum of squared errors
890@item satd
891sum of absolute Hadamard transformed differences
892@item dct
893sum of absolute DCT transformed differences
894@item psnr
895sum of squared quantization errors (avoid, low quality)
896@item bit
897number of bits needed for the block
898@item rd
899rate distortion optimal, slow
900@item zero
9010
902@item vsad
903sum of absolute vertical differences
904@item vsse
905sum of squared vertical differences
906@item nsse
907noise preserving sum of squared differences
908@item w53
9095/3 wavelet, only used in snow
910@item w97
9119/7 wavelet, only used in snow
912@item dctmax
913
914@item chroma
915
916@end table
917
918@item border_mask @var{float} (@emph{encoding,video})
919Increase the quantizer for macroblocks close to borders.
920
921@item mblmin @var{integer} (@emph{encoding,video})
922Set min macroblock lagrange factor (VBR).
923
924@item mblmax @var{integer} (@emph{encoding,video})
925Set max macroblock lagrange factor (VBR).
926
927@item mepc @var{integer} (@emph{encoding,video})
928Set motion estimation bitrate penalty compensation (1.0 = 256).
929
930@item skip_loop_filter @var{integer} (@emph{decoding,video})
931@item skip_idct @var{integer} (@emph{decoding,video})
932@item skip_frame @var{integer} (@emph{decoding,video})
933
934Make decoder discard processing depending on the frame type selected
935by the option value.
936
937@option{skip_loop_filter} skips frame loop filtering, @option{skip_idct}
938skips frame IDCT/dequantization, @option{skip_frame} skips decoding.
939
940Possible values:
941@table @samp
942@item none
943Discard no frame.
944
945@item default
946Discard useless frames like 0-sized frames.
947
948@item noref
949Discard all non-reference frames.
950
951@item bidir
952Discard all bidirectional frames.
953
954@item nokey
955Discard all frames excepts keyframes.
956
957@item all
958Discard all frames.
959@end table
960
961Default value is @samp{default}.
962
963@item bidir_refine @var{integer} (@emph{encoding,video})
964Refine the two motion vectors used in bidirectional macroblocks.
965
966@item brd_scale @var{integer} (@emph{encoding,video})
967Downscale frames for dynamic B-frame decision.
968
969@item keyint_min @var{integer} (@emph{encoding,video})
970Set minimum interval between IDR-frames.
971
972@item refs @var{integer} (@emph{encoding,video})
973Set reference frames to consider for motion compensation.
974
975@item chromaoffset @var{integer} (@emph{encoding,video})
976Set chroma qp offset from luma.
977
978@item trellis @var{integer} (@emph{encoding,audio,video})
979Set rate-distortion optimal quantization.
980
981@item sc_factor @var{integer} (@emph{encoding,video})
982Set value multiplied by qscale for each frame and added to
983scene_change_score.
984
985@item mv0_threshold @var{integer} (@emph{encoding,video})
986@item b_sensitivity @var{integer} (@emph{encoding,video})
987Adjust sensitivity of b_frame_strategy 1.
988
989@item compression_level @var{integer} (@emph{encoding,audio,video})
990@item min_prediction_order @var{integer} (@emph{encoding,audio})
991@item max_prediction_order @var{integer} (@emph{encoding,audio})
992@item timecode_frame_start @var{integer} (@emph{encoding,video})
993Set GOP timecode frame start number, in non drop frame format.
994
995@item request_channels @var{integer} (@emph{decoding,audio})
996Set desired number of audio channels.
997
998@item bits_per_raw_sample @var{integer}
999@item channel_layout @var{integer} (@emph{decoding/encoding,audio})
1000
1001Possible values:
1002@table @samp
1003@end table
1004@item request_channel_layout @var{integer} (@emph{decoding,audio})
1005
1006Possible values:
1007@table @samp
1008@end table
1009@item rc_max_vbv_use @var{float} (@emph{encoding,video})
1010@item rc_min_vbv_use @var{float} (@emph{encoding,video})
1011@item ticks_per_frame @var{integer} (@emph{decoding/encoding,audio,video})
1012@item color_primaries @var{integer} (@emph{decoding/encoding,video})
1013@item color_trc @var{integer} (@emph{decoding/encoding,video})
1014@item colorspace @var{integer} (@emph{decoding/encoding,video})
1015@item color_range @var{integer} (@emph{decoding/encoding,video})
1016@item chroma_sample_location @var{integer} (@emph{decoding/encoding,video})
1017
1018@item log_level_offset @var{integer}
1019Set the log level offset.
1020
1021@item slices @var{integer} (@emph{encoding,video})
1022Number of slices, used in parallelized encoding.
1023
1024@item thread_type @var{flags} (@emph{decoding/encoding,video})
1025Select multithreading type.
1026
1027Possible values:
1028@table @samp
1029@item slice
1030
1031@item frame
1032
1033@end table
1034@item audio_service_type @var{integer} (@emph{encoding,audio})
1035Set audio service type.
1036
1037Possible values:
1038@table @samp
1039@item ma
1040Main Audio Service
1041@item ef
1042Effects
1043@item vi
1044Visually Impaired
1045@item hi
1046Hearing Impaired
1047@item di
1048Dialogue
1049@item co
1050Commentary
1051@item em
1052Emergency
1053@item vo
1054Voice Over
1055@item ka
1056Karaoke
1057@end table
1058
1059@item request_sample_fmt @var{sample_fmt} (@emph{decoding,audio})
1060Set sample format audio decoders should prefer. Default value is
1061@code{none}.
1062
1063@item pkt_timebase @var{rational number}
1064
1065@item sub_charenc @var{encoding} (@emph{decoding,subtitles})
1066Set the input subtitles character encoding.
1067
1068@item field_order @var{field_order} (@emph{video})
1069Set/override the field order of the video.
1070Possible values:
1071@table @samp
1072@item progressive
1073Progressive video
1074@item tt
1075Interlaced video, top field coded and displayed first
1076@item bb
1077Interlaced video, bottom field coded and displayed first
1078@item tb
1079Interlaced video, top coded first, bottom displayed first
1080@item bt
1081Interlaced video, bottom coded first, top displayed first
1082@end table
1083
1084@item skip_alpha @var{integer} (@emph{decoding,video})
1085Set to 1 to disable processing alpha (transparency). This works like the
1086@samp{gray} flag in the @option{flags} option which skips chroma information
1087instead of alpha. Default is 0.
1088@end table
1089
1090@c man end CODEC OPTIONS
1091
1092@include decoders.texi
1093@include encoders.texi
1094
generated by cgit at 2024-05-17 03:37:36 (GMT)