xvidenc (-xvidencopts)

      次のモードが利用可能です: 固定ビットレート (CBR), fixed quantiz-
      er and two pass.
      turbo (2パスのみ)
             Dramatically speeds up pass one using faster algorithms and dis-
             abling CPU-intensive options.  This will probably reduce  global
             PSNR  a  little  bit and change individual frame type and PSNR a
             little bit more.
      bitrate=<数値> (CBR or two pass mode)


             決定されます. (default: 687kbits/s).
             Switch to fixed quantizer mode and specify the quantizer  to  be
      zones=<zone0>[/<zone1>[/...]] (CBR or two pass mode)
             User  specified  quality  for  specific  parts (ending, credits,
             ...).  Each zone is  <start-frame>,<mode>,<value>  where  <mode>
             may be
                q    Constant quantizer override, where value=<2.0-31.0> rep-
                     resents the quantizer value.
                w    Ratecontrol  weight  override,  where  value=<0.01-2.00>
                     represents the quality correction in %.
                     Encodes all frames starting with frame 90000 at constant
                     quantizer 20.
                     Encode frames 0-10000  at  10%  bitrate,  encode  frames
                     90000 up to the end at constant quantizer 20.  Note that
                     the second zone is needed to delimit the first zone,  as
                     without  it everything up until frame 89999 would be en-
                     coded at 10% bitrate.
             動き予測の精度を意味します. 値が大きいほどほど精度が高まりますが

       CPUパワーも消費します。(標準では: 6). ですからリアルタイムエンコ        ードが必要な場合は値を低くするとよいでしょう.

             Encode the fields of interlaced video material.  Turn  this  op-
             tion on for interlaced content.
             NOTE: Should you rescale the video, you would need an interlace-
             aware   resizer,   which   you    can    activate    with    -vf
             Use  4  motion  vectors  per macroblock.  This might give better
             compression, but slows down encoding.
             WARNING: As of XviD-1.0.x, this option is  no  longer  available
             separately,  and its functionality is included in the me_quality
             option.  When me_quality > 4, 4mv is activated.
             This parameter controls the number of frames the CBR  rate  con-
             troller will wait before reacting to bitrate changes and compen-
             sating for them to obtain a constant bitrate over  an  averaging
             range of frames.
             Real  CBR  is hard to achieve.  Depending on the video material,
             bitrate can be variable, and hard to  predict.   Therefore  XviD
             uses  an averaging period for which it guarantees a given amount
             of bits (minus a small variation).  This settings expresses  the
             "number  of frames" for which XviD averages bitrate and tries to
             achieve CBR.
             size of the rate control buffer
             CBR mode: min & max quantizer for all frames (default: 2-31)
             two pass mode: min &  max  quantizer  for  I/P-frames  (default:
             WARNING:  As  of  XviD-1.0.x,  this  option  is  replaced by the
             [min|max]_[i|p|b]quant options.
      min_key_interval=<value> (two pass only)
             minimum interval between keyframes (default: 0)
             maximum interval between keyframes (default: 10*fps)
             Use MPEG quantizers instead of H.263.  For  high  bitrates,  you
             will find that MPEG quantization preserves more detail.  For low
             bitrates, the smoothing of H.263 will give you less block noise.
             When using custom matrices, MPEG must be used.
             WARNING:  As  of  XviD-1.0.x,  this  option  is  replaced by the
             quant_type option.
             Decide whether to use MPEG or H.263 quantizers  on  a  frame-by-
             frame basis (two pass mode only).
             WARNING: This will generate an illegal bitstream, and most like-
             ly not be decodable by any MPEG-4 decoder besides libavcodec  or
             WARNING: As of XviD-1.0.x, this option is no longer available.
      keyframe_boost=<0-1000> (two pass mode only)
             Shift  some  bits  from  the pool for other frame types to intra
             frames, thus improving keyframe quality.  This amount is an  ex-
             tra  percentage,  so  a value of 10 will give your keyframes 10%
             more bits than normal (default: 0).
      kfthreshold=<value> (two pass mode only)
             Works together with kfreduction.  Determines  the  minimum  dis-
             tance  below  which  you consider that two frames are considered
             consecutive and treated  differently  according  to  kfreduction
             (default: 10).
      kfreduction=<0-100> (two pass mode only)
             The  above  two  settings  can  be  used  to  adjust the size of
             keyframes that you consider too close to the first (in  a  row).
             kfthreshold  sets  the range in which keyframes are reduced, and
             kfreduction determines the bitrate reduction they get.  The last
             I-frame will get treated normally (default: 30).
             Generate DivX5 compatible B-frames (default: on).  This seems to
             be mandatory only for old versions of DivX's decoder.
             WARNING: As of  XviD-1.0.x,  this  option  is  replaced  by  the
             closed_gop option.
             Make  XviD  discard  chroma  planes  so  the  encoded  video  is
             greyscale only.  Note that this does not speed up  encoding,  it
             just  prevents  chroma data from being written in the last stage
             of encoding.
             Save per-frame statistics in ./xvid.dbg. (This is  not  the  two
             pass control file.)
      The following options are only available with the latest stable releas-
      es of XviD 1.0.x (api4).
             This option is meant to solve frame-order issues  when  encoding
             to container formats like AVI that cannot cope with out-of-order
             frames.  In practice, most decoders (both software and hardware)
             are  able  to deal with frame-order themselves, and may get con-
             fused when this option is turned on, so you can safely leave  if
             off, unless you really know what you are doing.
             WARNING:  This  will generate an illegal bitstream, and will not
             be decodable by ISO-MPEG-4 decoders except DivX/libavcodec/XviD.
             WARNING: This will also store a fake DivX version in the file so
             the bug autodetection of some decoders might be confused.
             Maximum number of B-frames to put between  I/P-frames  (default:
             quantizer  ratio between B- and non-B-frames, 150=1.50 (default:
             quantizer offset between B- and non-B-frames, 100=1.00 (default:
             This setting allows you to specify what priority to place on the
             use of B-frames.  The higher the value, the higher the probabil-
             ity  of B-frames being used (default: 0).  Do not forget that B-
             frames usually have a higher quantizer, and therefore aggressive
             production of B-frames may cause worse visual quality.
             This  option  tells  XviD  to close every GOP (Group Of Pictures
             bounded by two I-frames), which makes GOPs independent from each
             other.   This just implies that the last frame of the GOP is ei-
             ther a P-frame or a N-frame but not a B-frame.  It is usually  a
             good idea to turn this option on (default: on).
      frame_drop_ratio=<0-100> (max_bframes=0 only)
             This  setting  allows  the  creation of variable framerate video
             streams.  The value of the setting specifies a  threshold  under
             which,  if the difference of the following frame to the previous
             frame is below or equal to this threshold, a frame gets not cod-
             ed  (a  so  called n-vop is placed in the stream).  On playback,
             when reaching an n-vop the previous frame will be displayed.
             WARNING: Playing with this setting may result in a jerky  video,
             so use it at your own risks!
             MPEG-4  uses a half pixel precision for its motion search by de-
             fault.  The standard proposes a mode where encoders are  allowed
             to  use quarter pixel precision.  This option usually results in
             a sharper image.  Unfortunately it has a great impact on bitrate
             and sometimes the higher bitrate use will prevent it from giving
             a better image quality at a fixed bitrate.  It is better to test
             with  and  without this option and see whether it is worth acti-
             Enable Global Motion Compensation,  which  makes  XviD  generate
             special  frames (GMC-frames) which are well suited for Pan/Zoom/
             Rotating images.  Whether or not the use  of  this  option  will
             save bits is highly dependent on the source material.
             Trellis  Quantization  is a kind of adaptive quantization method
             that saves bits by modifying quantized coefficients to make them
             more compressible by the entropy encoder.  Its impact on quality
             is good, and if VHQ uses too much CPU for you, this setting  can
             be  a  good  alternative to save a few bits (and gain quality at
             fixed bitrate) at a lesser cost than with VHQ (default: on).
             Activate this if your encoded sequence is an anime/cartoon.   It
             modifies  some XviD internal thresholds so XviD takes better de-
             cisions on frame types and motion vectors for flat looking  car-
             Sets  the type of quantizer to use.  For high bitrates, you will
             find that MPEG quantization preserves more detail.  For low  bi-
             trates,  the  smoothing of H.263 will give you less block noise.
             When using custom matrices, MPEG quantization must be used.
             The usual motion estimation algorithm uses  only  the  luminance
             information  to  find  the best motion vector.  However for some
             video material, using the chroma planes  can  help  find  better
             vectors.   This setting toggles the use of chroma planes for mo-
             tion estimation (default: on).
             Enable a chroma optimizer prefilter.  It will do some extra mag-
             ic on color information to minimize the stepped-stairs effect on
             edges.  It will improve quality at the cost of  encoding  speed.
             It  reduces PSNR by nature, as the mathematical deviation to the
             original picture will get bigger, but the subjective image qual-
             ity  will  raise.   Since  it  works with color information, you
             might want to turn it off when encoding in greyscale.
             Activates high-quality prediction of AC coefficients  for  intra
             frames from neighbor blocks (default: on).
             The  motion  search  algorithm is based on a search in the usual
             color domain and tries to find a motion  vector  that  minimizes
             the  difference  between  the  reference  frame  and the encoded
             frame.  With this setting activated, XviD will also use the fre-
             quency domain (DCT) to search for a motion vector that minimizes
             not only the spatial difference but also the encoding length  of
             the block.  Fastest to slowest:
                0    off
                1    mode decision (inter/intra MB) (default)
                2    limited search
                3    medium search
                4    wide search
             Adaptive  quantization  allows the macroblock quantizers to vary
             inside each frame.  This is a 'psychosensory'  setting  that  is
             supposed to make use of the fact that the human eye tends to no-
             tice fewer details in very bright and very  dark  parts  of  the
             picture.   It  compresses  those areas more strongly than medium
             ones, which will save bits that can  be  spent  again  on  other
             frames, raising overall subjective quality and possibly reducing
             minimum I-frame quantizer (default: 2)
             maximum I-frame quantizer (default: 31)
             minimum P-frame quantizer (default: 2)
             maximum P-frame quantizer (default: 31)
             minimum B-frame quantizer (default: 2)
             maximum B-frame quantizer (default: 31)
             Load a custom intra matrix file.  You can build such a file with
             xvid4conf's matrix editor.
             Load a custom inter matrix file.  You can build such a file with
             xvid4conf's matrix editor.
             This setting allows XviD to take a certain  percentage  of  bits
             away  from  high  bitrate  scenes  and give them back to the bit
             reservoir.  You could also use this if you have a clip  with  so
             many  bits allocated to high-bitrate scenes that the low(er)-bi-
             trate scenes start to look bad (default: 0).
             This setting allows XviD to give a certain percentage  of  extra
             bits  to  the low bitrate scenes, taking a few bits from the en-
             tire clip.  This might come in handy if you have a  few  low-bi-
             trate scenes that are still blocky (default: 0).
             During  pass one of two pass encoding, a scaled bitrate curve is
             computed.  The difference between that expected  curve  and  the
             result  obtained during encoding is called overflow.  Obviously,
             the two pass rate controller tries to compensate for that  over-
             flow,  distributing  it over the next frames.  This setting con-
             trols how much of the overflow is distributed every  time  there
             is  a  new  frame.   Low values allow lazy overflow control, big
             rate bursts are compensated for more slowly (could lead to  lack
             of  precision for small clips).  Higher values will make changes
             in bit redistribution more abrupt, possibly too  abrupt  if  you
             set it too high, creating artifacts (default: 5).
             NOTE:  This setting impacts quality a lot, play with it careful-
             During the frame bit allocation, overflow control  may  increase
             the frame size.  This parameter specifies the maximum percentage
             by which the overflow control is allowed to increase  the  frame
             size, compared to the ideal curve allocation (default: 5).
             During  the  frame bit allocation, overflow control may decrease
             the frame size.  This parameter specifies the maximum percentage
             by  which  the overflow control is allowed to decrease the frame
             size, compared to the ideal curve allocation (default: 5).
             Specifies a frame average overhead per frame, in bytes.  Most of
             the time users express their target bitrate for video w/o taking
             care of the video container overhead.  This small  but  (mostly)
             constant overhead can cause the target file size to be exceeded.
             XviD allows users to set the amount of overhead  per  frame  the
             container  generates  (give only an average per frame).  0 has a
             special meaning, it lets XviD use its own  default  values  (de-
             fault: 24 - AVI average overhead).
             Restricts options and VBV (peak bitrate over a short period) ac-
             cording to the Simple, Advanced Simple and DivX  profiles.   The
             resulting videos should be playable on standalone players adher-
             ing to these profile specifications.
                     no restrictions (default)
                     simple profile at level 0
                     simple profile at level 1
                     simple profile at level 2
                     simple profile at level 3
                     advanced simple profile at level 0
                     advanced simple profile at level 1
                     advanced simple profile at level 2
                     advanced simple profile at level 3
                     advanced simple profile at level 4
                     advanced simple profile at level 5
                     DXN handheld profile
                     DXN portable NTSC profile
                     DXN portable PAL profile
                     DXN home theater NTSC profile
                     DXN home theater PAL profile
                     DXN HDTV profile
             NOTE: These profiles should be used in conjunction with  an  ap-
             propriate -ffourcc.  Generally DX50 is applicable, as some play-
             ers do not recognize XviD but most recognize DivX.
             Specifies the Pixel Aspect Ratio mode (not to be  confused  with
             DAR,  the  Display Aspect Ratio).  PAR is the ratio of the width
             and height of a single pixel.  So both are  related  like  this:
             DAR = PAR * (width/height).
             MPEG-4  defines 5 pixel aspect ratios and one extended one, giv-
             ing the opportunity to specify a specific pixel aspect ratio.  5
             standard modes can be specified:
                     It is the usual PAR for PC content.  Pixels are a square
                     PAL standard 4:3 PAR.  Pixels are rectangles.
                     same as above
                     same as above
                     same as above (Do not forget to give the exact ratio.)
                     Allows you to specify your own pixel aspect  ratio  with
                     par_width and par_height.
             NOTE:  In  general,  setting  aspect  and  autoaspect options is
      par_width=<1-255> (par=ext only)
             Specifies the width of the custom pixel aspect ratio.
      par_height=<1-255> (par=ext only)
             Specifies the height of the custom pixel aspect ratio.
      aspect=<x/y | f (float value)>
             Store movie aspect internally, just like MPEG files.  Much nicer
             solution  than  rescaling,  because  quality  is  not decreased.
             MPlayer and a few others players will play these files  correct-
             ly,  others will display them with the wrong aspect.  The aspect
             parameter can be given as a ratio or a floating point number.
             Same as the aspect option, but  automatically  computes  aspect,
             taking into account all the adjustments (crop/expand/scale/etc.)
             made in the filter chain.
             Print the PSNR (peak signal to noise ratio) for the whole  video
             after  encoding  and  store  the per frame PSNR in a file with a
             name like 'psnr_hhmmss.log' in the current directory.   Returned
             values are in dB (decibel), the higher the better.
      The following option is only available in XviD 1.1.x.
             This  setting  allows  vector candidates for B-frames to be used
             for the encoding chosen using a rate distortion optimized opera-
             tor, which is what is done for P-frames by the vhq option.  This
             produces nicer-looking B-frames while incurring almost  no  per-
             formance penalty (default: 1).
      The following option is only available in the CVS version of XviD.
             Create n threads to run the motion estimation (default: 0).  The
             maximum number of threads that can be used is the picture height
             divided by 16.

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Last-modified: 2008-03-20 (木) 01:42:59 (5932d)