Open Mash Cross Reference
mash/codec/p64/p64.1

   .TH P64 1 "14 June 1993"
   .UC 4
   .SH NAME
   p64 \- P64 compression and decompression
   .SH SYNOPSIS
   .B
   p64  [-d [-c]] [-NTSC] [-CIF] [-QCIF]
   .B
        [-a StartNumber] [-b EndNumber]
  .B
       [-f FrameRate] [-k FrameskipNumber] [-o] [-p]
  .B
       [-i MCSearchLimit] [-q Quantization] [-v] [-y]
  .B
       [-r Target Rate] [-x Target Filesize]
  .B
       [-s StreamFile] [-z ComponentFileSuffix i]
  .B
       ComponentFilePrefix1 [ComponentFilePrefix2 ComponentFilePrefix3]
  .br
  .SH DESCRIPTION
  .I p64
  is a telecommunication image sequence compression/decompression
  program that performs CCITT H.261 encoding and decoding.
  .PP
  .SH OPTIONS
  .TP
  .B -NTSC
  indicates that the source frame size for the Luminance component is
  352x240 and for the Chrominance components is 176x120. This is the
  default size.
  .TP
  .B -CIF
  indicates that the source frame size for the Luminance component is
  352x288 and for the Chrominance components is 176x144.
  .TP
  .B -QCIF
  indicates that the source frame size for the Luminance component is
  176x144 and for the Chrominance components is 88x72.
  .TP
  .B -a
  denotes the following value to be the start of the filename index
  [inclusive]. Defaults to 0.
  .TP
  .B -b
  denotes the following value to be the end of the filename index
  [inclusive]. Defaults to 0.
  .TP
  .B -c
  for the decoder, it indicates to save to a CIF style file.  Always
  compatible with QCIF or NTSC modes.
  .TP
  .B -d
  enables the decoder.
  The only options useful for the decoder are the filename specifications;
  the rest of the information is used for encoding.
  .TP
  .B -f
  is the FrameRate, or the number of frames per second. The default
  number is 30 (frames/second), regardless of
  .B -PAL
  or
  .B -NTSC
  mode.
  .TP
  .B -i
  is the diameter of the motion estimation search. The diameter must be
  inclusively between 1 and 31, designating a region from interframe
  only (0,0) search, to full search (+- 15, +- 15).  (Default 15).
  .TP
  .B -k
  is the FrameSkip index, representing the spacing between each frame.
  A value of 1 indicates that every frame is to be transmitted. A value
  of 2 indicates every other frame is to be transmitted. In general, the
  number of transmitted frames per second is the FrameRate divided by
  FrameSkip.
  .TP
  .B -o
  signals that the program interpreter will read the control algorithms
  from the standard input.
  .TP
  .B -p
  enables parity checking for the frames.
  (Disabled under normal compilation for 1992
  CCITT specifications.) This checks the validity of
  the reference frame stores on the decoder end. While the parity is
  correct for this system's encoder and decoder, some parity errors (on
  the least significant bits) can occur in
  .I normal
  operation because of unmatched inverse DCT's between arbitrary encoders and
  decoders.
  .TP
  .B -q
  gives a value for the quantization
  not in the presence of rate control,
  which automatically changes the quantization values.
  If rate control is specified, this parameter gives a value for the
  initial quantization of the first frame (which the program usually
  takes an educated guess at).
 .TP
 .B -r
 specified a rate for the coded stream in bits per second. If this is
 enabled, a buffer model is used to limit the size of the coding
 stream.
 .TP
 .B -s
 specifies the filename to store the coded image. If unspecified it
 defaults to
 .B ComponentFilePrefix0.p64.
 .TP
 .B -v
 designates that quantization decisions are to be written to standard
 output.
 .TP
 .B -x
 gives a target filesize for the compressed stream. This overrides the
 rate option
 .B -r
 , if specified.  Note that the filesize will
 generally be larger than the target filesize because of remaining bits
 in the buffer.
 .TP
 .B -y
 enables the double-precision floating point Reference DCT. The default
 is the Chen DCT.
 .TP
 .B -z
 denotes the component file suffixes in sequential order. For example
 .B
  -z .y.clr -z .u.clr -z .v.clr
 indicates that the luminance and the two chrominance files
 end with a suffix of
 .B
 \&.y.clr, \&.u.clr,
 and
 .B \&.v.clr,
 in that order. If unspecified, the suffixes
 default to
 .B
 \&.Y, \*.U,\fR
 and
 .B \&.V.
 .TP
 .B ComponentFilePrefix\fIn\fR
 must be specified. In general, the other component files share the
 same prefix and will default to
 .B ComponentFilePrefix1
 if not explicitly specified. However, in some cases the prefix is what
 changes in the file and we can specify this individually.
 .PP
 .SH EXAMPLES
 To encode a set of raw raster scan YCbCr (also known as digital YUV) files with
 dimension 352x240 Y, 176x120 U,V,
 with labels,
 .B
 hello0.Y hello0.U hello0.V,
 .B
 hello1.Y hello1.U hello1.V,
 .B
 \&...,
 .B
 hello12.Y hello12.U hello12.V
 through the p64 encoder, type
 
 .br
 .B
 p64 -a 0 -b 12 hello -s hello.p64
 .br
 
 This creates the output file
 .B hello.p64.
 In order to decode such a file into a sequence of image files with
 prefix
 .B goodbye,
 type
 
 .br
 .B
 p64 -d -s hello.p64 goodbye
 .br
 
 The output will be placed in the files
 .B
 goodbye0.Y goodbye0.U goodbye0.V,
 .B
 goodbye1.Y goodbye1.U goodbye1.V,
 .B
 \&...,
 .B
 goodbye12.Y goodbye12.U goodbye12.V.
 These image sequences can be displayed by the
 .I cv
 program.
 The image sequences can also be converted to ppm and back through
 the programs
 .I cyuv2ppm
 and
 .I ppm2cyuv
 Those utility programs available by anonymous ftp from
 .I havefun.stanford.edu:pub/cv/CVv1.2.1.tar.Z.
 There are more options within an internal program interpreter.
 Please see the accompanying documentation in
 .I doc.ps
 for more details.
 .PP
 .SH FTP
 .I p64
 is available by anonymous ftp from
 .I havefun.stanford.edu:pub/p64/P64v1.2.tar.Z.
 .PP
 .SH BUGS
 Somewhat slower than many commercial implementations.
 Please inform the author at achung@cs.stanford.edu if you have
 such a sequence available or if any bugs are found.
 .PP
 .SH AUTHOR
 .PP
 Andy Hung