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       transcode - LINUX video stream processing tool


       transcode -i name [-o name] [-y vmod,amod]
                 [-w vbitrate [ ,vkeyframes [ ,vcrispness ] ]]
                 [-a atrack [ ,vtrack ]]
                 [-b abitrate [ ,is_vbr [ ,quality [ ,mode ] ] ]]
                 [-M demuxer_mode] [-F codec_string] [other options]


       transcode supports a huge range of options, as described in detail in
       further section. Only one option is mandatory: -i name, for supplying
       the input main (video) source. All other options are discretionary and
       they can be skipped. Most commonly needed options are -o, -y, -w, -a,
       -b, -M, -F and a fair number of transcode session needs a little more
       than those. See section below for full description of all transcode
       options. To inspect the properties of a module, such as their
       parameters or the help text, use the 'tcmodinfo' tool.


       transcode is a linux text-console utility for video stream processing,
       running on a platform that supports shared libraries and threads.

       It supports a huge range of options, as described in detail in further
       section. Only one option is mandatory: -i name, for supplying the input
       main (video) source. All other options are discretionary and they can
       be skipped. Most commonly needed options are -o, -y, -w, -a, -b, -M, -F
       and a fair number of transcode session needs a little more than those.
       See section below for full description of all transcode options.

       Decoding and encoding is done by loading modules that are responsible
       for feeding transcode with raw video/audio streams (import modules) and
       encoding the frames (export modules).

       It supports elementary video and audio frame transformations, including
       de-interlacing or fast resizing of video frames and loading of external

       A number of modules are included to enable import of DVDs on-the-fly,
       MPEG elementary (ES) or program streams (VOB), MPEG video, Digital
       Video (DV), YUV4MPEG streams, NuppelVideo file format, AVI based codecs
       and raw or compressed (pass-through) video frames and export modules
       for writing DivX;-), XviD, DivX 4.xx/5.xx or uncompressed AVI and raw
       files with MPEG, AC3 (pass-through) or PCM audio.

       Additional export modules to write single frames (PPM) or YUV4MPEG
       streams are available, as well as an interface import module to the
       avifile library.

       It's modular concept is intended to provide flexibility and easy user
       extensibility to include other video/audio codecs or filetypes. A set
       of tools is included to demux (tcdemux), extract (tcextract) and decode
       (tcdecode) the sources into raw video/audio streams for import, probing
       (tcprobe) and scanning (tcscan) your sources and to enable
       post-processing of AVI files, fixing AVI file header information
       (avifix), merging multiple files (avimerge), splitting large AVI files
       (avisplit) to fit on a CD and avisync to correct AV-offsyncs.


           use AC3 as internal audio codec [off]. Only pass-through supported.

       -B  n[,m[,M]]
           resize to height-n*M rows [,width-m*M] columns [off,32].  M must be
           one of 8, 16 or 32. It makes no difference which M you use. You
           might look at the fast flag of the -Z option if you don not want to
           calculate n and m yourself.

       -C  mode
           enable anti-aliasing mode (1-3) [off].

               de-interlace effects only

               resize effects only

               process full frame (slow)

       -D  num
           sync video start with audio frame num [0].

       -E  r[,b[,c]]
           audio output samplerate [Hz], bits per sample and channels [as
           input]. The option "-J resample" must be provided for export
           modules not capable of re-sampling. Samplerate and bits per sample
           can be specified as 0 to mean "same as input"; this allows
           converting from stereo to mono while leaving the other parameters
           alone (-E 0,0,1).

       -F  codec_string
           encoder parameter strings [module dependent]. The -F parameter has
           different meanings for different export modules. Those meanings are
           documented in transcode_export(1) manual page.

       -G  val
           Gamma correction (0.0-10.0) [off]. A value of 1.0 does not change
           anything. A value lower than 1.0 will make the picture "brighter",
           a value above 1.0 will make it "darker".

       -H  n
           auto-probe n MB of source (0=disable) default [1]. Use a higher
           value than the default to detect all subtitles in the VOB.

       -I  mode
           enable de-interlacing mode (1-5) [off].


               "interpolate scanlines" linear interpolation (takes the average
               of the surronding even rows to determine the odd rows), and
               copies the even rows as is.


               "handled by encoder" tells the encoding code to handle the fact
               that the frames are interlaced. Most codecs do not handle this.


               "zoom to full frame" drops to to half size, then zooms out.
               This can cause excessive blurring which is not always unwanted.
               On the other hand results are quite good.


               "drop field / half height" drop every other field and keep half


               "interpolate scanlines / blend frames" linear blend (similar to
               -vop pp=lb in mplayer) this, like linear blend calculates the
               odd rows as the average of the surrounding even rows, and also
               calculates the even rows as an average of the original even
               rows and also calculates the even rows as an average of the
               original odd rows and averages the calculated and original
               rows. Something like avg (avg(row1,row3), avg(row2, row4))

       -J  filter1[,filter2[,...]]
           apply external filter plugins [off]. The avalaible import modules
           and their options are documented into the transcode_filter(1)
           manual page.  Note: You can specify more than one -J argument. The
           order of filter arguments specify in which order the filters are
           applied. Note also, for transcode internally it makes no difference
           whether you do "-J filter1 -J filter2" or "-J filter1,filter2". Use
           'tcmodinfo -i NAME' to get more information about the filter_NAME.
           Not all filters support this but most of them do. Some of the
           filter plugins have additional documentation in the docs/

       -L  n
           seek to VOB stream offset nx2kB default [0]. This option is usually
           calculated automatically when giving --nav_seek and -c.

           enable black/white by removing colors mode (grayscale) [off].
           Please note this does not necessarily lead to a smaller image /
           better compression. For YUV mode, this is done by emptying the
           chroma planes, for RGB mode a weightend grayscale value is

       -M  mode
           demuxer PES AV sync modes (0-4) [1].

               The demuxer takes care that the right video frames go together
               with the right audio frame. This can sometimes be a complex
               task and transcode tries to aid you as much as possible.
               WARNING: It does make a difference if you (the user) specifies
               a demuxer to use or if transcode resp. tcprobe(1) chooses the
               one which it thinks is right for your material. This is done on
               purpose to avoid mystic side-effects. So think twice, wether
               you specify a demuxer or let transcode choose one or you might
               end up with an off-sync result.

               Pass-through. Do not mess with the stream, switch off any
               synchronization/demuxing process.

               PTS only (default). Synchronize video and audio by inspecting
               PTS/DTS time stamps of audio and video. Preferred mode for PAL
               VOB streams and DVDs.

               NTSC VOB stream synchronization feature. This mode generates
               synchronization information for transcode by analyzing the
               frame display time.

               (like -M 1): sync AV at initial PTS, but invokes
               "-D/--av_fine_ms" options internally based on "tcprobe" PTS
               analysis. PTS stands for Presentation Time Stamp.

               (like -M 2): initial PTS / enforce frame rate, with additional
               frame rate enforcement (for NTSC).

       -N  format
           select export format. Default is mp3 for audio, and
           module-dependant format for video. This option has two different
           behaviours and accepts two different set of options, as side-effect
           of ongoing export module transition. For old-style modules (current
           default, as found in 1.0.x series), argument is audio format ID has
           hexadecimal value: see below for a list of recognized IDs. Default
           id, so default format for audio exported track, is MP3 (0x55). If
           you are using, the transcode's the new-style encode/multiplex
           modules (still under development, see the encode and multiplex
           directories), argument is a comma-separated pair of export format
           names. Use tcmodinfo tool to check out what new-style export module
           support what formats.

           Available format for old-style behaviour are:

               PCM uncompressed audio

               MPEG layer-2 aka MP2

               MPEG layer-3 aka MP3. Also have a look at --lame_preset if you
               intend to do VBR audio.

               AC3 audio

               OGG/Vorbis audio

           skip flushing of buffers at encoder stop [off, do flushing at each

       -P  flag
           pass-through flag (0=off|1=V|2=A|3=A+V) [0]. Pass-through for flag
           != 1 is broken and not a trivial thing to fix.

           You can pass-through DV video, AVI files and MPEG2 video. When
           doing MPEG2 pass-through (together with the -y raw module), you can
           give a requantization factor by using -w (for example -w 1.5), this
           will make the MPEG2 stream smaller.

           The pass-through mode is useful for reconstruction of a broken
           index of an AVI file. The -x ffmpeg import-module analyzes the
           compressed bitstream and can detect a keyframe for DIV3, MPEG4
           (DivX, XviD, ..) and other formats. It then sets an internal flag
           which the export module will respect when writing the frame out.

       -Q  n[,m]
           encoding[,decoding] quality (0=fastest-5=best) [5,5].

       -R  n[,f1[,f2]]
           enable multi-pass encoding (0-3) [0,divx4.log,pcm.log].

           0 Constant bitrate (CBR) encoding. [default]
               The codec tries to achieve constant bitrate output. This means,
               each encoded frame is mostly the same size. This type of
               encoding can help in maintaining constant filling of hardware
               buffer on set top players or smooth streaming over networks. By
               the way, Constant bitrate is often obtained sacrifying quality
               during high motion scenes.

           1 Variable bitrate encoding: First pass.
               In this mode, the codec analyses the complete sequence in order
               to collect data that can improve the distribution of bits in a
               second VBR pass. The collected data is written to second sub
               argument (default: divx4.log). This data is codec dependant and
               cannot be used across codecs. It is strongly advised to use the
               same codec settings for the VBR analysis pass and the VBR
               encoding pass if you want predictable results.

               The video output of the first pass is not of much use and can
               grow very large. It's a good idea to not save the video output
               to a file but directly to /dev/null. Usually the bitrate is
               ignored during first pass.

               Disabling audio export makes sense too, so use -y codec,null.
               It is not recommended to disable the audio import because
               transcode might drop video frames to keep audio and video in
               sync. This is not possible when the audio import is disabled.
               It may lead to the fact that the codec will see a different
               sequence of frames which effectively renders the log file

           2 Variable bitrate encoding: Second pass.
               The first pass allowed the codec collecting data about the
               complete sequence. During the second pass, the codec will use
               that data in order to find an efficient bit distribution that
               respects both the desired bitrate and the natural bitrate curve
               shape. This ensures a good compromise between quality and
               desired bitrate.

               Make sure you activate both sound and video encoding during
               this pass.

           3 Constant quantizer encoding.
               The quantizer is the "compression level" of the picture. The
               lower the quantizer is, the higher is the quality of the
               picture. This mode can help in making sure the sequence is
               encoded at constant quality, but no prediction can be made on
               the final bitrate. When using this mode, the -w option changes
               its meaning, it now takes the quantizer ranging from 1 to 31.
               Note that constant quantizer encoding is not supported with
               some codecs (notably mpeg1/2/4 with -y ffmpeg).

       -S  unit[,s1-s2]
           process program stream unit[,s1-s2] sequences [0,all]. This option
           is a bit redundant to --psu*. This option lets you specify which
           units you want to have decoded or skipped. At a program stream unit
           boundary, all (internal) mpeg timers are reset to 0. tcprobe will
           tell you how many units are in one file.

       -T  t[,c[,a]]
           select DVD title[,chapter[,angle]] [1,1,1]. Only a single chapter
           is transcoded. Use -T 1,-1 to trancode all chapters in a row. You
           can even specify chapter ranges.

       -U  base
           process DVD in chapter mode to base-ch%02d.avi [off].

       -V  format
           select video layout / colour space for internal processing.
           Possible values for this options are: yuv420p (default), yuv422p,

           yuv420p is default because it is most codecs' internal format so
           there is no need for conversions. Some modules may not support it
           though: use rgb in that case.

           rgb24 is the old (pre-0.6.13) transcode internal format. Most
           codecs do not support this format natively and have to convert it
           to/from YUV first, so only use this option if you're really sure or
           you want to use a module that doesn't support YUV.

           yuv422p is an experimental feature and a developers playground. Not
           many import, export and filter modules support this colorspace. A
           4:2:2 colorspace offers much more quality than the consumer
           oriented 4:2:0 colorspaces like I420/YV12. Most equipment in film
           and video post-production uses YUV422. YUV422 doubles the precision
           for chroma (color difference) information in the image.

           All internal transformations are supported in YUV422 mode
           (clipping, flipping, zooming, etc).

       -W  n,m[,nav_file]
           autosplit and process part n of m (VOB only) [off]

       -X  n[,m,[M]]
           resize to height+n*M rows [,width+m*M] columns [off,32]. M must be
           one of 8, 16 or 32. It makes no difference which M you use. You
           might look at the fast flag of the -Z option if you do not want to
           calculate n and m yourself.

       -Y  top[,left[,bottom[,right]]]
           select (encoder) frame region by clipping border. Negative values
           add a border [off].

       -Z  widthxheight[,fast|interlaced]
           resize to width columns, height rows with filtering
           [off,notfast,notinterlaced]. If fast is given, transcode will
           calculate the parameters for -X and/or -B. The file fast can only
           be used when the import and export geometry of an image is a
           multiple of 8.

           In fast mode, a faster but less precise resizing algorithm will be
           used resulting in a slightly less good quality. Beside this (small)
           drawback, it is worth a try.

           If interlaced is given, transcode will assume the frame is
           interlaced when resizing, and resize each field independently. This
           will give better results on interlaced video, but is incompatible
           with fast mode. Also, the height (both old and new) must be a
           multiple of 4.

           It is also possible to omit width OR height. In this case,
           transcode will calculate the missing value using the import aspect
           ratio. The new value will be aligned to be a multiple of 8. Using
           an additional fast or interlaced is also possible.

           Examples (assume input is a 16:9 coded file at 720x576):

                                       -Z 576x328           uses filtered zoom.
                                       -Z 576x328,fast      uses fast zoom.
                                       -Z 576x,fast         guess 328 and do fast zoom.
                                       -Z x328,interlaced   guess 576 and do interlaced zoom.

           If you also set --export_prof, you can use just "fast" to indicate
           that fast resizing is wanted (likewise with "interlaced").

       -a  ach[,vch]
           extract audio[,video] track for encoding.

       -b  b[,v,[q,[m]]]
           audio encoder bitrate kBits/s[,vbr[,quality[,mode]]] [128,0,5,0]

           The mode parameter specifies which modus lame should use for
           encoding. Available modes are:

               Joint Stereo (default)

               Full stereo


       -c  f1-f2[,f3-f4[, ... ] ]
           encode only frames f1-f2 [and f3-f4]. Default is to encode all
           available frames. Use this and you'll get statistics about
           remaining encoding time. The f[N] parameters may also be timecodes
           in the HH:MM:SS.FRAME format. Example:

                                       -c 500-0:5:01,:10:20-1:18:02.1

           Will encode only from frame 500 to 5 minutes and 1 second and from
           10 min, 20 sec to 1 hour, 18 min, 2 sec and one frame.

           Note that transcode starts counting frames at 0 and excludes the
           last frame specified. That means that "-c 0-100" will encoded 100
           frames starting at frame 0 up to frame 99

           swap bytes in audio stream [off]. In most cases, DVD PCM audio
           tracks require swapping of audio bytes

       -e  r[,b[,c]]
           PCM audio stream parameter. Sample rate [Hz], bits per sample and
           number of channels [48000,16,2]. Normally this is autodetected.

       -f  rate[,frc]
           import video frame rate[,frc] [25.000,0]. If frc (frame rate code)
           is specified, transcode will calculate the precise frames per
           second internally. Valid values for frc are:

               23.976 (24000/1001.0)



               29.970 (30000/1001.0)



               59.940 (2 * 29.970)







       -g  WidthxHeight
           video stream frame size [720x576].

           print out usage information.

       -i  name
           input file/directory/device/mountpoint/host name, default is

       -j  top[,left[,bottom[,right]]]
           select frame region by clipping border. Negative values add a
           border [off].

           swap red/blue (Cb/Cr) in video frame [off]. Use if people have blue

           mirror video frame [off].

       -m  file
           write audio stream to separate file [off].

       -n  0xnn
           import audio format id [0x2000]. Normally, this is autodetected.

       -o  file
           output file name, default is [/dev/null].

       -p  file
           read audio stream from separate file [off].

       -q  debuglevel
           possible values for debuglevel:











       -r  n[,m]
           reduce video height/width by n[,m] [off]. Example: -r 2 will
           rescale the framesize of a 720x576 file to 360x288.

       -s  gain,[center,[front,[rear]]]
           increase volume of audio stream by gain,[center,front,rear] default

       -t  n,base
           split output to base%03d.avi with n frames [off].

       -u  m[,n]
           use m framebuffer[,n threads] for AV processing [10,1].

           print version.

       -w  b[,k[,c]]
           encoder bitrate[,keyframes[,crispness]] [(6000 for MPEG 1/2, 1800
           for others),250,100].

       --video_max_bitrate  b
           Use b as maximal bitrate (kbps) when encoding variable bitrate

       -x  vmod[,amod]
           video[,audio] import modules [auto,auto]. If omitted, transcode
           will probefor appropriate import modules. The avalaible import
           modules and their options are documented into the
           transcode_import(1) manual page.

       -y  vmod[,amod[,mmod]]
           video[,audio[,multiplex]] export modules [null]. If omitted,
           transcode will encode to the null module. If a multiplex module is
           given, transcode will use the new-style encode/multiplex modules
           (still under development, see the encode and multiplex
           directories); if no multiplex module is given, the traditional
           export modules will be used. The avalaible export, encoder and
           multiplexor modules and their options are documented into the
           transcode_export(1) manual page.

       --accel  type
           enforce experimental IA32 acceleration for type [autodetect].  type
           may be one of

               No acceleration

               plain x86 assembly

               MMX instruction set

               3DNow! instruction set

               SSE instruction set

               SSE2 instruction set

       --avi_limit N
           split/rotate output AVI file after N MB [2048].

       --avi_comments  F
           Read AVI header comments from file F [off]. The AVI file format
           supports so-called tomb-stone data. It can be used to write
           annotations into the AVI file.

           See the file docs/avi_comments.txt for a sample input file with all
           tags. When the file is read, empty lines and lines starting with
           '#' are ignored. The syntax is: "TAG<space>STRING". The order of
           the tags does not matter. If a tag has no string following it, it
           is ignored. That means, you can use the file docs/avi_comments.txt
           as input and only fill out the fields you want.

           A very simple example is:

                                       INAM My 1st Birthday
                                       ISBJ My first steps!
                                       IART My proud family

           Keep in mind that there is no endless space in the AVI header, most
           likely its around 1000 bytes.

       --zoom_filter  string
           use filter string for video resampling -Z [Lanczos3] The following
           filters are available:



           Lanczos3 (default)





           use percentage mode for cluster encoding -W> [off]

       --cluster_chunks  a-b
           process chunk range instead of selected chunk [off]

       --export_asr  C
           set export aspect ratio code C [as input] Valid codes for C are:





       --export_prof  S
           WARNING: this option will be renamed as --export_profile in future

           Select an export profile {vcd, svcd, xvcd, dvd}
           [-pal|-ntsc|-secam]. Default is no profile.

           If you set this meta option to one of the values below, transcode
           will adjust some internal paramaters as well as geometry and
           clipping. If no export modules are specified, mpeg2enc for video
           and mp2enc for audio are used when compiled with mjpegtools

           Valid values for S are e.g. vcd, vcd-pal, vcd-ntsc, svcd, svcd-pal,

           xvcd profile is equal to svcd except that it allows for up to 9000
           Kbps video bitrate (default is 5000) and arbitrary audio

           When one of the above is used, transcode will calculate the needed
           clipping and resizing values for you based on the import and export
           aspect ratio. This is especially handy if you want to encode a 16:9
           DVD into a 4:3 SVCD for example. Transcode internally then sets
           --pre_clip to add the black bars ("letterboxing").

           If you use "vcd" instead of "vcd-pal" or "vcd-ntsc", transcode will
           make an educated guess if PAL or NTSC vcd is wanted. The same is
           true for the other profiles. When the input file has no aspect
           ratio information at all, transcode guesses it based on the import
           frame sizes. You can set the import aspect ratio by giving
           --import_asr CODE.

           Examples (assume input is a 16:9 coded file at 720x576 (PAL)):

                                       --export_prof svcd      clip top/bot -96; resizes to 480x576
                                       --export_prof vcd-ntsc  clip top/bot -96; resizes to 352x240

           This enables simpilified commandlines where transcode tries to set
           sensible values for mpeg export. When you don't specify an export
           module with -y, mpeg2enc will be used.

                                       transcode -i vob/ --export_prof svcd -Z fast -o test

           The ffmpeg export module `-y ffmpeg' does support profiles as well.
           The module tries to be smart and sets internal ffmpeg parameters
           which are otherwise quite tricky to find out. Usage is similar to
           the above.

                                       transcode -i vob/ --export_prof dvd -y ffmpeg -o test -m test.ac3
                                       tcmplex -m d -i test.m2v -p test.ac3 -o test.mpg

       --export_par  C[,N]
           set export pixel aspect ratio to C[,N]. To encode anamorphic
           material, transcode can encode the target pixel aspect ratio into
           the file. This is NOT the actual aspect ratio of the image, but
           only the amount by which every single pixel is stretched when
           played with an aspect ratio aware application, like mplayer.

           To encode at non standard aspect ratios, set both C and N. E.g. to
           make every pixel twice as high as it's wide (e.g. to scale back to
           normal size after deinterlacing by dropping every second line).

           If C and N are specified, the value set for C does give the pixel
           aspect ratio of the width and N the one for the height. If only C
           is specified, the table below applies.

           Valid codes for C are

               1:1 No stretching

               12:11 5:4 image to 4:3 (ex: 720x576 -> 768x576)

               10:11 3:2 image to 4:3 (ex: 720x480 -> 640x480)

               16:11 5:4 image to 16:9 (ex: 720x576 -> 1024x576)

               40:33 3:2 image to 16:9 (ex: 720x480 -> 872x480)

       --import_asr  C
           set import aspect ratio code C [autoprobed]

           Valid codes for C are





           try to keep aspect ratio (only with -Z) [off]

           The --keep_asr options changes the meaning of -Z. It tries to fit
           the video into a framesize specified by -Z by keeping the original
           aspect ratio.

                                       +----------------+                            +---480-----+
                                       |                |                            | black     |
                                       |720x306 = 2.35:1| -> -Z 480x480 --keep_asr ->|-----------4
                                       |                |                            | 480x204   8
                                       +----------------+                            |-----------0
                                       | black     |

           Consider --keep_asr a wrapper for calculating -Y options and -Z

           use external mplayer binary to probe stream, reset default import
           modules as mplayer ones [off]. Default is to use internal probing
           code. Using this option without mplayer import modules (-x mplayer)
           can lead to unpredictable and possibly wrong results.

       --quantizers  min,max
           set encoder min/max quantizer. This is meaningfull only for video
           codecs of MPEG family. For other kind of codecs, this options is
           harmless. [2,31]

       --divx_rc  p,rp,rr
           divx encoder rate control parameter [2000,10,20]

       --divx_vbv_prof  N
           divx5 encoder VBV profile (0=free-5=hiqhq) [3]. Sets a predefined
           profile for the Video Bitrate Verifier. If N is set to zero, no
           profile is applied and the user specified values from --divx_vbv
           are used.

           Valid profiles

               Free/No profile ( Use supplied values )

               Handheld ( 320, 16, 3072 )

               Portable ( 1920, 64, 12288 )

               Home Theatre ( 10000, 192, 36864 )

               High Definition ( 20000, 384, 73728 )

       --divx_vbv  br,sz,oc
           divx5 encoder VBV params (bitrate,size,occup.) [10000,192,36864]
           These parameters are normally set through the profile parameter
           --divx_vbv_prof. Do not mess with theses value unless you are
           absolutely sure of what you are doing. Transcode internally
           multiplicates vbv_bitrate with 400, vbv_size with 16384 and
           vbv_occupancy with 64 to ensure the supplied values are multiples
           of what the encoder library wants.

       --export_fps  rate[,frc]
           set export frame rate (and code) [as input].Valid values for frc

           frc rate

               23.976 (24000/1001.0)



               29.970 (30000/1001.0)



               59.940 (2 * 29.970)







       --export_frc  F
           set export frame rate code F [as input].  Obsolete, use
           --export_fps 0,F

           disable smooth dropping (for variable fps clips) [off]. See
           /docs/framerate.txt for more information.

           set MPEG 3:2 pulldown flags on export [off]

       --antialias_para  w,b
           center pixel weight, xy-bias [0.333,0.500]

           disable internal audio frame sample adjustment [off]

           disable lame bitreservoir for MP3 encoding [off]

       --config_dir  dir
           Assume config files are in this dir. This only affects the -y
           ffmpeg and -y xvid4 modules. It gives the path where the modules
           search for their configuration.

       --lame_preset  name[,fast]
           use lame preset with name [off]. Lame features some built-in
           presets. Those presets are designed to provide the highest possible
           quality. They have for the most part been subject to and tuned via
           rigorous listening tests to verify and achieve this objective.
           These are continually updated to coincide with the latest
           developments that occur and as a result should provide you with
           nearly the best quality currently possible from LAME. Any of those
           VBR presets can also be used in fast mode, using the new vbr
           algorithm. This mode is faster, but its quality could be a little
           lower. To enable the fast mode, append ",fast"

           <N kbps>
               Using this preset will usually give you good quality at a
               specified bitrate. Depending on the bitrate entered, this
               preset will determine the optimal settings for that particular
               situation. While this approach works, it is not nearly as
               flexible as VBR, and usually will not reach the same quality
               level as VBR at higher bitrates. ABR.

               This preset should provide near transparency to most people on
               most music. The resulting bitrate should be in the 150-180kbps
               range, according to music complexity. VBR.

               This preset should generally be transparent to most people on
               most music and is already quite high in quality. The resulting
               bitrate should be in the 170-210kbps range, according to music
               complexity. VBR.

               If you have extremely good hearing and similar equipment, this
               preset will provide slightly higher quality than the "standard"
               mode. The resulting bitrate should be in the 200-240kbps range,
               according to music complexity. VBR.

               This preset will usually be overkill for most people and most
               situations, but if you must have the absolute highest quality
               with no regard to filesize, this is the way to go. This preset
               is the highest preset quality available. 320kbps CBR.

           (taken from[1]

       --av_fine_ms  t
           AV fine-tuning shift t in millisecs [autodetect] also see -D.

       --nav_seek  file
           use VOB or AVI navigation file [off]. Generate a nav file with
           tcdemux -W >nav_log for VOB files or with aviindex(1) for AVI

           process VOB in PSU, -o is a filemask incl. %d [off]. PSU means
           Program Stream Unit and this mode is useful for (mostly) NTSC DVDs
           which have several program stream units.

       --psu_chunks  a-b
           process only selected units a-b for PSU mode [all]

           encode to single file in chapter/psu/directory mode [off]. If you
           don't give this option, you'll end up with several files in one of
           the above mentioned modes. It is still possible to merge them with


           (EXPERIMENTAL) enable multiple input mode: intelligently join input
           files in import. The inputs can be expressed using standard POSIX
           globbing. While theorically all input modules are supported, it is
           safe to use this only when dealing with constant-sized audio (PCM)
           and intra-frame only video codecs (es: MJPEG). To be safe, use this
           mode with im, ffmpeg and raw import modules.

       --pre_clip  t[,l[,b[,r]]]
           select initial frame region by clipping border [off]

       --post_clip  t[,l[,b[,r]]]
           select final frame region by clipping border [off]

           disable liba52 dynamic range compression [enabled]. If you dont
           specify this option, liba52 will provide the default behaviour,
           which is to apply the full dynamic range compression as specified
           in the A/52 stream. This basically makes the loud sounds softer,
           and the soft sounds louder, so you can more easily listen to the
           stream in a noisy environment without disturbing anyone.

           If you let it enabled this this will totally disable the dynamic
           range compression and provide a playback more adapted to a movie
           theater or a listening room.

           demux AC3/A52 to separate channels [off]

           disable liba52 dolby surround [enabled]. Selects whether the output
           is plain stereo (if the option is set) or if it is Dolby Pro Logic
           - also called Dolby surround or 3:1 - downmix (if the option is not

           disable colored log messages. By default transcode use colors in
           log messages in order to easily distinguish message classes. That
           behaviour can be problematic if output of transcode is a file or a
           pipe, so this option came handful.

       --dir_mode  base
           process directory contents to base-%03d.avi [off]

       --frame_interval  N
           select only every Nth frame to be exported [1]

       --encode_fields  C
           enable field based encoding (if supported) [off]. This option takes
           an argument if given to denote the order of fields. If the option
           is not given, it defaults to progressive (do not assume the picture
           is interlaced)

           Valid codes for C are:

               progressive (default)

               top-field first

               bottom-field first

       --dv_yuy2_mode, --dv_yv12_mode
           Indicates that libdv decodes Digital Video frames in YUY2 (packed)
           or YV12 (planar) mode, respectively. Normally transcode figures out
           the correct mode automatically, but if you try to transcode PAL DV
           files and the results look strange, try one of these options.

       --write_pid  file
           write pid of signal thread to file [off]. Enables you to terminate
           transcode cleanly by sending a SIGINT (2) to the pid in file.
           Please note file will be overwritten. Usage example

                                       $ transcode ... --write_pid /tmp/ &
                                       $ kill -2 `cat /tmp/`

       --nice  N
           set niceness to N [off]. The option --nice which renices transcode
           to the given positive or negative value. -10 sets a high priority;
           +10 a low priority. This might be useful for cluster mode.

       --progress_meter  N
           select type of progress meter [1]. Selects the type of progress
           message printed by transcode:

               no progress meter

               standard progress meter

               raw progress data (written to standard output)

           Scripts that need progress data should use type 2, since the format
           of type 1 is subject to change without notice.

       --progress_rate  N
           print progress every N frames [1]. Controls how frequently the
           status message is printed (every N frames).

       --socket  FILE
           Open a socket to accept commands while running. See tcmodinfo(1)
           and /docs/filter-socket.txt for more information about the


           if set, forces the colored logging off for all the tools of
           transcode suite.


           Most source material parameter are auto-detected.

           Clipping region options are expanded symmetrically. Examples:

           -j 80 will be expanded to -j 80,0,80,0

           -j 80,8 will be expanded to -j 80,8,80,8

           -j 80,8,10 will be expanded to -j 80,8,10,8

           maximum image size is 1920x1088.

           The video frame operations ordering is fixed: "-j -I -X -B -Z -Y -r
           -z -l -k -K -G -C" (executed from left to right).

           Shrinking the image with '-B' is not possible if the image
           width/height is not a multiple of 8, 16 or 32.

           Expanding the image with '-X' is not possible if the image
           width/height is not a multiple of 8, 16 or 32.

           The final frame width/height should be a multiple of 8. (to avoid
           encoding problems with some codecs)

               Reducing the video height/width by 2,4,8 Option '-r factor' can
               be used to shrink the video image by a constant factor, this
               factor can be 2,4 or 8.

               Clipping and changing the aspect ratio transcode uses 3 steps
               to produce the input image for the export modules

                   Clipping of the input image.

                   Changing the aspect ratio of the 1) output.

                   Clipping of the 2) output.


           Bits per pixel (bits/pixel) is a value transcode calculates and
           prints when starting up. It is mainly useful when encoding to MPEG4
           (xvid, divx, etc). You'll see line like

           [transcode] V: bits/pixel | 0.237

           Simplified said, bits/pixel quantifies how good an encode will be.
           Although this value depends heavily on the used input material, as
           a general rule of thump it can be said that values greater or close
           to 0.2 will result in good encodes, encodes with values less than
           0.15 will have noticeable artifacts.

           Bits per pixel depends on the resolution, bitrate and frames per
           second. If you have a low value ( < 0.15), you might want to raise
           the bitrate or encode at a lower resolution. The exact formula is

                                       bpp =  ------------------


           AC3 / Multiple channels

           When you do import an audio stream which has more then two audio
           channels - this is usually the case for AC3 audio - transcode will
           automagically downmix to two channels (stereo). You'll see line

           [transcode] A: downmix | 5 channels -> 2 channels

           This is done, because most encoders and audio filters can not
           handle more than 2 channels correctly. The PCM internal
           representation does not support more than two channels, audio will
           be downmixed to stereo No downmix will happen, if you use AC3 as
           the internal audio codec or use audio pass-through.


       The following command will read it's input from the DVD drive (I assume
       /dev/dvd is a symbolic link to the actual DVD device) and produce a
       splitted divx4 movie according to the chapter information on the DVD
       medium. The output files will be named my_movie-ch00.avi,
       my_movie-ch01.avi ...

                           transcode -i /dev/dvd/ -x dvd -j 16,0 -B 5,0 -Y 40,8 -s 4.47 -U my_movie -y xvid -w 1618


       -j 16,0
       will be expanded to
       -j 16,0,16,0
       and results in 16 rows from the top and the bottom of the image to be cut off. This may be usefull if the source consists of black top and bottom bars.

       -B 5,0
       to shrink the resulting image by 5*32=160 rows in height.

       -Y 40,8
       will be expanded to
       -Y 40,8,40,8
       and tells
       to ...

       -s 4.47
       to increase audio volume by a factor 4.47.

       -U my_movie
       to operate in chapter mode and produce output to files named
       my_movie-ch01.avi.... You can either merge the files afterwards with avimerge or add the option --no_split to the command line.

       -y xvid
       to use the export module which in turn uses the XviD encoder to encode the video.

       -w 1618
       to set the encoder bitrate to 1618 which is lower than the default of 1800 and results in smaller files with the loss of visual quality.

       Lets assume that you have an NTSC DVD (720x480) and you want to make an NTSC-SVCD
           The frame size of the DVD movie is 720x480 @ 16:9. For the purpose of frame resizing, the width 720 is not relavant (that is, it will not be used in the following reasoning). It is not needed because the original frame size is really defined by the frame height and aspect ratio. The _final result_ should be 640x480, encoded as 480x480 @ 4:3 (the height 480 multiplied by the aspect ratio 4:3 gives the width 640). This same frame size (640x480) can also be encoded as 640x360 @ 16:9 (the height 360 by the aspect ratio 16:9 gives the width 640).

           As the _original video_ has aspect ratio 16:9, first we resize to 640x360, keeping that aspect ratio. But the aspect ratio has to be changed to 4:3. To find the frame size in the new aspect ratio the height 360 is multiplied by the new aspect ratio, giving the width 480. This is accomplished with the transcode options "--export_asr
           2 -Z 480x360,fast".

           To avoid stretching the video height in this change (because the new aspect ratio is less than the original), black borders should be added at the top and bottom of the video, bringing the frame to the desired 480x480 @ 4:3 size. The transcode option for this is "-Y -60,0,-60,0".

           If for some reason (maybe a subtitle filter) the black borders (of height 60 each) should be added before resizing the frame and changing the aspect ratio to 4:3. One reason for that would be the need of running a _pre_ filter after adding the black borders. Then the options "-j" or "--pre_clip" can be used instead of "-Y". In this case the black border height has to be recalculated by applying the aspect ratio 4:3 to the value alreadyfound: 60 * (4/3) = 80. The transcode options "-j -80,0,-80,0" or "--pre_clip -80,0,-80,0" are then used instead of "-Y -60,0,-60,0", and "-Z 480x360,fast" is replaced by "-Z 480x480,fast".


       Written by Thomas Oestreich
       <>, Tilmann Bitterberg and the

       See the AUTHORS file for details.


       transcode_export(1) , transcode_filter(1) , transcode_import(1) ,
       avifix(1) , avisync(1) , avimerge(1) , avisplit(1) , tcprobe(1) ,
       tcscan(1) , tccat(1) , tcdemux(1) , tcextract(1) , tcdecode(1) ,
       tcmodinfo(1) , tcxmlcheck(1) , transcode(1)


       Frequently asked questions (FAQ) at [1] Example
       transcode sessions at [1]


       Yes, there are bugs in transcode! Do your part and report them

       For details, see [1]