dmconvert(1)                                                      dmconvert(1)


NAME
     dmconvert - digital media file conversion utility

SYNOPSIS
     dmconvert [options] infile1 [... infileN] [outfile]

DESCRIPTION
     dmconvert converts between different digital media files.  Input files
     are combined, converted, and written to an output file of a selected
     format.  dmconvert may also be used to describe input files without
     converting to an output file.

     Supported files include the following audio, image, and movie formats.
     The output file format is specified with the -f option, and may be any of
     the formats except those marked describe-only or read-only.

              Format   Description

     Audio    aifc     Audio Interchange File Format w/ compression
              aiff     Audio Interchange File Format
              avr      Audio Visual Research
              bicsf    Berkeley/IRCAM/CARL Sound File Format
              iff      Amiga IFF/8SVX
            d midi     Musical Instrument Digital Interface
              mpeg1a   MPEG-1 audio bitstream
              next     NeXT/Sun audio
              rawaudio Raw audio data
              sd2      Sound Designer II
              sf2      Creative Labs SoundFont2 Compatible
              smp      SampleVision
              voc      Creative Labs VOC
              wave     WAVE audio

     Image    bmp      Microsoft Windows Bit Map
              cur      Microsoft Windows Cursor
            w eps      Encapsulated PostScript
              fit      File Format for Image Tiling
              gif      Graphics Image File
              hdf      Hierarchical Data Format
              ico      Microsoft Windows Icon
              icon     Sun Icon and Cursor
              jfif     JPEG File Interchange Format
              mpnt     Apple Macintosh MacPaint
              pbm      Portable Bit Map
            r pcd      Kodak PhotoCD
              pgm      Portable Grayscale Map
              pic      PIXAR Picture
              pict     Apple Macintosh QuickDraw/PICT
              pix      Alias Pixel
              pnm      Portable Any Map
              ppm      Portable Pixel Map
            w ps       PostScript


              ras      Sun Raster
            w rawrgb   Raw pixels packed as rgb
              rgb      SGI RGB image
              rgbA     SGI RGB image with generated alpha
              rgba     SGI RGB image with alpha
              rla      Wavefront Raster
              rle      Utah Runlength-encoded
              rpbm     Raw Portable Bit Map
              rpgm     Raw Portable Grayscale Map
              rpnm     Raw Portable Any Map
              rppm     Raw Portable Pixel Map
            r soft     SoftImage PIC
              synu     SDSC Synu
              tga      Truevision Targa
              tiff     Tagged Image File Format
              viff     Khoros Visualization Image File Format
              x        Stardent AVS X
              xbm      X11 Bit Map
              xwd      X Window Dump

     Movie    avi      AVI movie
              mpeg1s   MPEG-1 systems bitstream
              mpeg1v   MPEG-1 video bitstream
              qt       QuickTime
              sgimv    SGI movie
            r difdv    DIF/DV bitstream

     (d = describe-only, r = read-only, w = write-only)

     At most one audio track and one video track is converted for each file.
     Input QuickTime files with multiple tracks are rendered as a single
     combined audio track and a single combined video track.

     The audio track in the output is obtained by concatenating audio tracks
     from the inputs, and likewise for the video track.  Tracks to be written
     out may be selected and converted with the -p option.

     Sequences of image files may be specified in place of regular filename
     arguments by using special template strings.  These template names
     contain a '#' character, and are defined using the -n option.

     If dmconvert is stopped with SIGINT (<Ctrl C>), a valid output file is
     written with whatever data has been processed.  The signal SIGTERM also
     stops the program, but causes the output to be deleted.


CONTENTS
     The next six sections discuss the many features that are supported.  At
     the end of each section, several examples are provided to illustrate
     program usage.

     Options


     File Suboptions

     Audio Suboptions

     Video Suboptions

     Template Suboptions

     Conversions with Cosmo Movies


OPTIONS
     -h
          Display help.  No output file is generated.

     -D
          Describe the contents of the files.  No output file is generated.

     -d
          Describe files as they are converted.

     -s
          Use short format for describing files.

     -l
          Use long format for describing files.  Currently, this provides
          additional information only for some audio files.

     -q
          Quiet errors.  Do not print error messages.

     -v
          Verbose progress.  Print percentage completed during conversion.

     -f file_format[,suboptions]
          Output file specification.  File_format may be any of the digital
          media formats except those that are read-only.  Some file
          characteristics may be set with the suboptions described in the
          File Suboptions section.

     -p path[,suboptions]
          Enable the specified path to the output file.  Path is a track type
          and may be "audio" or "video".  Data conversion operations on enabled
          paths may be characterized by using the suboptions described in the
          Audio and Video Suboptions sections.

          If this option is not used, all tracks are enabled by default.  If
          this option is used, each track to be written out must be explicitly
          enabled.

     -n template_name[,suboptions]
          Image sequence templates.  Each filename may be in the form of a


          template that specifies a sequence of image files.  This option
          defines a template_name that may be used subsequently in place
          of any of the arguments infile1, ..., infileN, or outfile.

          template_name is a string with '#' characters designating integer
          indices to be filled in.  The number of '#' characters indicates
          the minimum field length for each index; left padding with zeros
          is performed as needed in order to meet this minimum.  By default,
          indices start at 0 and increment by 1 until either no more files
          exist (for inputs) or no more files need to be written (for outputs).
          A template may be customized using the suboptions described in the
          Template Suboptions section.

          If this option is not used, a filename with '#' characters is
          automatically interpreted as a template if the filename does not
          already exist as a regular file and, for outputs, if the selected
          file format is an image format.

     ------------
     * EXAMPLES *
     ------------

     Print help information.
     dmconvert -h

     Describe the input files.
     dmconvert -D -l in.aiff in.rgb in.movie in.mps

     Describe the digital media files in the current directory.
     dmconvert -D -s -q *

     Make an MPEG-1 audio bitstream from an AIFF audio file.
     dmconvert -f mpeg1a -p audio in.aiff out.mpa

     Make an audio/video SGI movie from an AIFF-C audio file and a
     video-only SGI movie.
     dmconvert -f sgimv -p audio -p video in.aifc in.movie out.movie

     Make a video-only QuickTime movie from an audio/video SGI movie.
     dmconvert -f qt -p video in.movie out.mov

     Make a sequence of SGI rgb files from the video track of an SGI movie.
     The output files will be named out00.rgb, out01.rgb, ...
     sh/csh: dmconvert -f rgb -p video -n out##.rgb in.movie out##.rgb
        ksh: dmconvert -f rgb -p video -n out####.rgb in.movie out####.rgb
     Please note that some shells such as ksh require escaping the # character.

     Make an AIFF audio file from a NeXT file and a WAVE file.  Also
     describe the files and print progress information.
     dmconvert -f aiff -p audio -d -v in.next in.wave out.aiff


FILE SUBOPTIONS
     The file suboptions are specified as a comma-separated list of
     subopt=value pairs.  These provide additional information about the
     output file.  The available suboptions are

     brate
          overall bitrate of the output file.  Supported for files
          that use MPEG-1, Cinepak, or Cosmo JPEG compression.  For
          files that contain only one track, this sets the bitrate
          of that track.

     loop
          default looping mode of the output movie during playback
          ("once", "loop", or "swing").  Supported for SGI movies.

     interleave
          granularity in seconds of audio and video interleaving.
          For example, to write audio and video in alternating chunks
          of duration 0.5 seconds each, use an interleave value of 0.5.
          Supported for SGI/QuickTime movies.

     paramfile
          parameter file for customizing outputs.  Supported for MPEG-1
          audio, video, and systems bitstreams.  For an example, see
          /usr/lib/dmconvert/mpeg1.par.

     ------------
     * EXAMPLES *
     ------------

     Make an MPEG-1 video bitstream at 1.5 Mbps.
     dmconvert -f mpeg1v,brate=1500000 in.movie out.mpv

     Make an SGI movie with a specific looping mode and interleave.
     dmconvert -f sgimv,loop=swing,interleave=0.1 in.movie out.movie

     Make an MPEG-1 systems bitstream using a parameter customization file.
     dmconvert -f mpeg1s,paramfile=mpeg1.par in.movie out.mps


AUDIO SUBOPTIONS
     The audio suboptions are specified as a comma-separated list of
     subopt=value pairs.  These are used to configure the processing of audio
     data from input to output.  Processing consists of a pipeline of
     individual conversion operations.  Suboptions may be specified in any
     order, but the actual order of operations is given by

       byteord->rate->channels->pcmmap/format/width->compression

     The available suboptions are

     rate


          frame rate of the output audio track.  If the input track
          has a different rate, automatic rate conversion is performed.
          For conversions between the standard rates, 8000, 11025, 16000,
          22050, 32000, 44100, and 48000 Hz, high quality filters are used.
          For conversions with other rates, simple algorithms of lower
          quality are used.

          In the special case of converting from 8012.8210513 Hz audio
          (common in NeXT files) to a rate other than 8000 Hz, the input
          samples are automatically interpreted as 8000 Hz so that the
          high quality filters are used.  To avoid this small pitch shift,
          first convert to an 8000 Hz sound track (the simple algorithm
          should be acceptable), then to the desired rate.

     stopatten
          stopband attenuation of the rate conversion filter (78.0, 96.0,
          or 120.0 dB); applies only to conversions between the standard
          rates.  Higher values produce better quality but require more
          computation.

     transw
          transition bandwidth of the rate conversion filter (1.0, 10.0,
          or 20.0 percent); applies only to conversions between the stand-
          ard rates.  Lower values produce better quality but require more
          computation.

     chan
          number of channels in the output audio track (1, 2, or 4).

     pcmmap
          PCM mapping of the output audio track.  Value may take the form
          "slope/intercept/minclip/maxclip" or just "slope", which is
          equivalent to "slope/0/0/0".  This maps output sample
          values to the range [intercept-slope,intercept+slope].  If
          minclip<maxclip, clipping to these limits is performed as well.

     format
          sample format in the output audio track ("2scomp", "unsigned",
          "float", or "double").

     width
          sample width in the output audio track (1-32 bits).  Not
          relevant for float or double sample formats.

     comp
          compression scheme to apply to the output audio track ("none",
          "g711a", "g711u", "g722", "g726", "g728", "gsm", "dvi", "mpeg1",
          or "multirate").  Supported for AIFF-C, NeXT/Sun, VOC, and WAVE
          files.  Not every compression scheme is supported by each of
          these.

     brate


          bitrate to use for the output audio track.  Supported for
          MPEG-1 compression.  If the output file has only one track
          and the file bitrate suboption is also specified, the file
          bitrate takes precedence.

     layer
          encoding layer to use for MPEG-1 compression (1, 2).

     chanmode
          channel mode to use for MPEG-1 or Multirate compression
          ("stereo", "joint", or "dual").  Related channels should be
          encoded as "stereo" or "joint".  The latter exploits inter-
          channel redundancy for better compression.  Independent
          channels should be encoded as "dual".

     bratepol
          bitrate policy to use for MPEG-1 or Multirate compression
          ("fixed", "constqual", or "lossless").  MPEG-1 encoding may
          operate at either a fixed bitrate or constant quality.
          Multirate encoding may operate at either constant quality
          or in lossless mode.

     nmr
          noise-to-mask-ratio to use for constant quality MPEG-1
          compression (-13.0 to 13.0 dB).  Zero yields a theoretically
          imperceptible noise level.  Positive values provide more
          compression but more noise, and negative values, vice versa.

     byteord
          byte ordering of the output audio track ("big" or "little"
          endian).  Supported for uncompressed raw audio output.

     The following suboptions describe the input.

     inraw
          indicates whether the input files consist of raw audio data
          ("true" or "false").  If true, no other input file formats
          are recognized.

     indataoff,inframecnt
          the data offset in bytes from the beginning of file, and the
          total number of audio frames.  Relevant only for raw audio
          inputs.

     inrate,inchan,informat,inwidth,incomp,inbyteord
          frame rate, channels, sample format, sample width, compression,
          and byte ordering of the input.  Relevant only for raw audio
          inputs.

     inpcmmap
          the PCM mapping that describes the input sample range.  Value
          is given in the same form as the output PCM mapping.  Input


          clipping will be performed before main conversions such as
          frame rate, channels, etc.


     ------------
     * EXAMPLES *
     ------------

     Make a 32 KHz AIFF file from an 8KHz input using the highest quality
     rate conversion.
     dmconvert -f aiff -p audio,rate=32000,stopatten=120.0,transw=1.0
     in.aiff out.aiff

     Make a two-channel AIFF file from a mono input.
     dmconvert -f aiff -p audio,chan=2 in.aiff out.aiff

     Make a NeXT file that has float samples.  Scale the samples to the range
     [-5.0,5.0] and also clip values less than -4.5 and greater than 4.5.
     dmconvert -f next -p audio,format=float,pcmmap=5.0/0.0/-4.5/4.5
     in.aiff out.next

     Make an AIFF file that has 8-bit twos-complement samples.
     dmconvert -f aiff -p audio,format=2scomp,width=8 in.aiff out.aiff

     Make an AIFF-C file that uses Layer II MPEG-1 compression at 192 Kbps,
     with the channels encoded under "joint" mode.
     dmconvert -f aifc -p audio,comp=mpeg1,brate=192000,layer=2,chanmode=joint
     in.aiff out.aifc

     Make an AIFF-C MPEG-1 file using constant quality encoding and a low
     noise-to-mask ratio.
     dmconvert -f aifc -p audio,comp=mpeg1,bratepol=constqual,nmr=-10.0
     in.aiff out.aifc

     Make a file of raw audio samples that are written as little-endian.
     dmconvert -f rawaudio -p audio,format=2scomp,width=16,byteord=little
     in.aiff out.raw

     Make a WAVE audio file from raw input samples.  The samples are extracted
     from the middle of the input file, and their characteristics are fully
     described.
     dmconvert -f wave -p audio,inraw=true,indataoff=100,inframecnt=4000,
     inrate=44100,inchan=2,informat=2scomp,inwidth=16,incomp=none,
     inbyteord=big,inpcmmap=30000 in.raw out.wave


VIDEO SUBOPTIONS
     The video suboptions are specified as a comma-separated list of
     subopt=value pairs.  These are used to configure the processing of video
     data from input to output.  Processing consists of a pipeline of
     individual conversion operations.  Suboptions may be specified in any


     order, but the actual order of operations is given by

       rate->interlace->layout/orientation->crop->filter->size->compression

     The available suboptions are

     rate
          frame rate of the output video track.  If the input track has a
          different rate, automatic rate conversion is performed.

     ratecvt
          type of rate conversion to use ("rptdrp" or "inv32").  Repeat-drop
          is the simpler scheme.  Inverse 3:2 pulldown may be used to convert
          30 to 24 fps, or 29.97 to 23.976 fps.

     il
          interlacing of the output video track.  May be "none" (non-
          interlaced), "even" (even lines temporally first), or "odd"
          (odd lines temporally first).

     ilcvt
          type of interlace conversion to use.  Supported types are

          "pn_interfield" (odd/even parity to non-interlaced)
               A non-linear filter is applied between the fields for
               high quality de-interlacing.

          "pn_combine" (odd/even parity to non-interlaced)
               The fields are temporally combined without modification.

          "np_separate" (non-interlaced to odd/even parity)
               The fields are temporally separated without modification.

          "pp_swap" (odd to even parity, or vice versa)
               The fields are temporally swapped without modification.

     fl
          frame layout of the output video track.  May be "full" (full
          frame) or "split" (split fields).  The frame layout indicates
          how video lines are stored, and is not the same as interlacing,
          which indicates how the lines are temporally sampled.  For
          example, interlaced video may be stored as full frames or split
          fields, whereas non-interlaced video is usually stored as full
          frames only.

          This suboption is supported for image files.  For SGI movies,
          the frame layout is currently restricted to split fields for
          interlaced data and full frames for non-interlaced data, so the
          interlacing suboption also serves to specify the output frame
          layout.

     or


          orientation of images in output video track.  May be "b2t"
          (bottom-to-top) or "t2b" (top-to-bottom).  Supported for making
          SGI movies.

     cropl,cropr,cropt,cropb
          number of pixels to crop from left, right, top, and bottom
          borders of input images.  For interlaced material, top and
          bottom cropping should be even numbers.

     filt
          filter to apply during conversion.  The following values
          are recognized.

          "vblur"
               blur images with vertical 1-2-1 convolution, where the
               center tap corresponds to the field opposite to that of
               the outer taps.  Useful for reducing flicker if output
               images are played back through video.  Supported for
               making image files and SGI/QuickTime movies.

          "soft", "softmax"
               soften images with normal or maximum settings.  Useful
               as a preprocessing step before compression.  Supported
               for MPEG-1 movies.

     sx,sy,size
          size of output image in pixels.  Supported for making image
          files and movies.  sx and sy are used to specify individual
          dimensions.  size is used to specify both dimensions, where
          the value is expressed as WxH (e.g. 640x480) or one of the
          strings "orig" or "sif".  For interlaced material, the height
          should be an even number.

     lbox
          letterboxing flag ("true" or "false").  If false, the input
          images are scaled as needed to fill the output size, which
          may require different scale factors in each dimension.  If
          true, a common scale factor is used and any remaining space
          is filled with black.  Supported for making image files and
          SGI/QuickTime movies.

     comp
          compression scheme to apply to the output video track ("none",
          "jpeg", "mvc1", "mvc2", "qt_anim", "qt_video", "qt_cvid",
          "qt_mjpega", "rle", "rle24" or "huffyuv").  The Compact Video
          scheme, "qt_cvid", is also known as Cinepak.  The "qt_mjpega"
          represents Quicktime's Motion JPEG Format A.  Supported for
          SGI/QuickTime movies. SGI movies cannot use scheme's with the
          "qt_" prefix.

     engine
          engine used during the conversion ("cosmo" or "sw").  Supported for


          JPEG compression or decompression.

     brate
          bitrate to use for the output video track.  Supported for MPEG-1,
          Cinepak, and Cosmo JPEG compression.  If the output file has only
          one track and the file bitrate suboption is also specified, the
          file bitrate takes precedence.

     squal
          spatial quality factor used in compression (0.0 - 1.0).  Supported
          for SGI/QuickTime movies.  This is useful for setting the spatial
          quality of video tracks compressed with JPEG or a QuickTime scheme.

     tqual
          temporal quality factor used in compression (0.0 - 1.0).  Supported
          for QuickTime movies.  This is useful for setting the temporal
          quality of tracks compressed with a QuickTime scheme.

     kdist
          distance between key frames.  Supported for QuickTime and MPEG-1
          video compression schemes.  For MPEG-1 this is equivalent to the
          N parameter, which gives the distance between I frames.

     rdist
          distance between reference frames.  Supported for MPEG-1 video
          compression.  This is equivalent to the M parameter, which gives
          the distance between I or P frames.  For example, the pattern
          IBBPBBI (M=3,N=6), would be specified by rdist=3 and kdist=6.

     The following suboptions describe the input, and are useful for adding
     information about image files.

     inrate,inil,infl
          frame rate, interlacing, and frame layout of input images.

     inpixasp
          pixel aspect ratio of input images.  This is a float defined as
          the vertical extent of a pixel divided by its horizontal extent.
          It may also be specified as one of the following strings - "sq"
          (square pixels), "c525" (CCIR601 525), or "c625" (CCIR601 625).
          Used in making SGI movies or MPEG-1 movies.

     ------------
     * EXAMPLES *
     ------------

     Make a 23.976 fps MPEG-1 video bitstream from a 29.97 fps SGI movie
     using inverse 3:2 pulldown.
     dmconvert -f mpeg1v -p video,rate=23.976,ratecvt=inv32 in.movie out.mpv

     Make a non-interlaced SGI movie from an even-interlaced SGI movie
     using interfield filtering.


     dmconvert -f sgimv -p video,il=none,ilcvt=pn_interfield in.movie out.movie

     Make a sequence of split field image files, out0.rgb, out1.rgb, ...,
     from an odd-interlaced SGI movie.
     dmconvert -f rgb -p video,fl=split -n out#.rgb in.movie out#.rgb

     Make a top-to-bottom SGI movie.
     dmconvert -f sgimv -p video,or=t2b in.movie out.movie

     Make an SGI movie by cropping, blurring, and resizing the input video.
     Use letterboxing during the resize.
     dmconvert -f sgimv -p video,cropl=10,cropr=10,filt=vblur,size=320x240,
     lbox=true in.movie out.movie

     Make an SGI movie with JPEG video at 10.0 Mbps, and use Cosmo to assist
     in the compression.
     dmconvert -f sgimv -p video,comp=jpeg,engine=cosmo,brate=10000000
     in.movie out.movie

     Make a QuickTime Cinepak movie at specific spatial and temporal qualities.
     dmconvert -f qt -p video,comp=qt_cvid,squal=0.9,tqual=0.5 in.movie out.mov

     Make a QuickTime Motion JPEG Format A movie which has odd interlaced
     fields.  This is a good format for cross-platform field based movies.
     dmconvert -f qt -p audio -p video,comp=qt_mjpega,il=odd movie out.mov

     Make an MPEG-1 systems bitstream with a video frame pattern IBBPBBI.
     The audio track is also written out.
     dmconvert -f mpeg1s -p audio -p video,kdist=6,rdist=3 in.movie out.mps

     Make an MPEG-1 video bitstream from the input image files in0.rgb,
     in1.rgb, ..., and provide information about the input data.
     dmconvert -f mpeg1v -p video,inrate=15.0,inil=even,infl=split,
     inpixasp=c525 -n in#.rgb in#.rgb out.mpv


TEMPLATE SUBOPTIONS
     The template suboptions are specified as a comma-separated list of
     subopt=value pairs.  These customize how the template name is expanded
     when it is used in place of a regular filename.

     The available suboptions are

     start
          starting index for the sequence of image files.

     end
          ending index for the sequence of image files.

     step
          increment to apply to the construction of indices.


     ------------
     * EXAMPLES *
     ------------

     Make an SGI movie from the images in.rgb.9, in.rgb.10, and in.rgb.11.
     dmconvert -f sgimv -n in.rgb.#,start=9,end=11,step=1 -p video
     in.rgb.# out.movie

     Make a sequence of ten SGI images from an input movie, and name them
     out01.rgb, out03.rgb, out05.rgb, ..., out19.rgb.
     dmconvert -f rgb -n out##.rgb,start=1,end=19,step=2 -p video
     in.movie out##.rgb


CONVERSIONS WITH COSMO MOVIES
     dmconvert may be used to convert from movies recorded with the Cosmo
     Compress option board (cl_cosmo(3dm)), or to produce movies that are
     playable by Cosmo.

     Cosmo movies are just SGI movies with particular video characteristics.
     No special treatment is necessary to use these movies as input files, but
     certain settings are required for creating movies playable by Cosmo.  The
     output video track should be constructed with comp=jpeg and or=t2b.
     Further, the dimensions, interlacing, and frame rate should match one of
     the following modes.

                        width     height       interlacing   frame rate
                        -----     ------       -----------   ----------
         NTSC           640       480 or 496   odd           29.97
         CCIR601-525    720       480 or 496   odd           29.97
         PAL            768       576          even          25
         CCIR601-625    720       576          even          25

     Half-widths and half-heights are also accepted in each mode.

     ------------
     * EXAMPLES *
     ------------

     Make an MPEG-1 movie from a Cosmo movie.
     dmconvert -vf mpeg1s -p audio -p video,sx=320,sy=240 cosmo.movie out.mps

     Make a QuickTime Cinepak movie from a Cosmo movie.
     dmconvert -vf qt -p audio -p video,comp=qt_cvid,sx=320,sy=240,rate=15.0
     cosmo.movie out.mov

     Make a Cosmo movie from another SGI movie.
     dmconvert -vf sgimv -p audio -p video,comp=jpeg,or=t2b,sx=640,sy=480,
     il=odd,rate=29.97 in.movie cosmo.movie


NOTES
     In order for some image files to be recognized, the filename should have
     an extension that matches the file format.  For example, if a Targa file
     "foo" is not recognized, then rename it as "foo.tga".

     MacPaint image files are always written as 576x720.

     Alpha channel is supported only for SGI images and SoftImage PIC files.
     The "rgbA" output file format computes alpha based on pixel luminance.

     Some command-line syntax changes have been made since previous releases.

         o the "sgirgb" file format is still supported, but the new
             equivalent is "rgba".
         o the "-p all" option should no longer be used.  This
             functionality is available from the "-f file_format",
             "-p audio", and "-p video" options.
         o the MPEG-1 "file" suboption is now called "paramfile".

     When reading TIFF images with 16 bits/component, the upper 8 bits are no
     longer ignored.  Its possible to revert to the old behaviour by setting
     the environment variable DMCONVERT_DISABLE_SCALE.

     This version does not support writing DIF/DV files.  A workaround is to
     generate a quicktime file and then convert that to DIF using a separate
     utility (such as the DVlink application included with the DVlink 1394
     card).

     For MPEG-1 movies, the video size defaults to "sif" (320x240) if no other
     size param is specified.


CAVEATS
     dmconvert relies on ImageVision for certain functionality.  Prior to IRIX
     6.5.25, dmconvert used the ImageVision 2.5 libraries, which rely on the
     DISPLAY environment variable.

     If the DISPLAY environment variable is set to a system that is down,
     dmconvert can hang for a long time prior to doing the conversion.

     A workaround for this is to set the DISPLAY environment variable to the
     local system, so that a connection can be made.  This can be done as
     follows:

     sh    : DISPLAY="0:0"; export DISPLAY

     csh   : setenv DISPLAY 0:0

     Note that versions of dmconvert shipped with IRIX 6.5.25 or later do not
     have this problem.


MPEG CAVEATS
     When converting to MPEG-1 systems streams, conversion of large amounts of
     data (typically over 1 GB) stops with the following message:

     dmconvert: SGI Compression Library error.  mux: buffer underflow; use
     higher systems bitrate

     Increasing the systems bitrate may or may not cause the problem to go
     away. If possible, breaking up the data into chunks and encoding them
     separately should work.


AUTHOR
     Silicon Graphics Computer Systems.  Portions developed at the San Diego
     Supercomputer Center.

     dmconvert uses the SGI Audio File, Compression, ImageVision, and Movie
     Libraries to access digital media data.

     Many of the image file formats are supported through the San Diego
     Supercomputer Center's image library (libim, libsdsc).  This library is
     available from anonymous ftp at sdsc.edu in the
     /pub/sdsc/graphics/imtools/ directory.  For more information, contact
     info@sdsc.edu.


FILES
     /usr/lib/dmconvert/mpeg1.par -- sample mpeg1 parameter file


SEE ALSO
     dminfo(1), dmplay(1), dmrecord(1),
     soundplayer(1), soundeditor(1),
     imgcopy(1), imginfo(1), imgview(1), imgworks(1),
     mediaconvert(1), movieplayer(1), capture(1), moviemaker(1),
     AFintro(3dm), CLintro(3dm), cl_cosmo(3dm), IL(3il), mvIntro(3dm), mpeg(4)


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