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- MPEG(1) USER COMMANDS MPEG(1)
-
- NAME
- mpeg - MPEG compression and decompression
-
- SYNOPSIS
- mpeg [-d] [-NTSC] [-CIF] [-QCIF] [-PF] [-NPS] [-MBPS mbps]
- [-UTC]
- [-a StartNumber] [-b EndNumber]
- [-h HorizontalSize] [-v VerticalSize]
- [-f FrameInterval] [-g GroupInterval]
- [-4] [-c] [-i MCSearchLimit] [-o] [-p PictureRate]
- [-q Quantization] [-r Target Rate]
- [-s StreamFile] [-x Target Filesize] [-y]
- [-z ComponentFileSuffix i]
- ComponentFilePrefix1 [ComponentFilePrefix2 Com-
- ponentFilePrefix3]
-
- DESCRIPTION
- mpeg is a multimedia image sequence
- compression/decompression program that performs MPEG encod-
- ing and decoding.
-
- OPTIONS
- -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.
- -CIF indicates that the source frame size for the Luminance
- component is 352x288 and for the Chrominance components
- is 176x144.
- -QCIF
- indicates that the source frame size for the Luminance
- component is 176x144 and for the Chrominance components
- is 88x72.
- -PF indicates that the component sizes specified by -h and
- -v are not multiples of 16 and furthermore that the
- input files (or output files) should be exactly that
- specified by the component size -h and -v (or as read
- from the compressed stream). Otherwise the input and
- output files will be the component size rounded up to a
- multiple of 16 in each dimension.
- -NPS The NPS option allows the encoder to encode without
- having the restriction that the last macroblock in a
- slice cannot be skipped. For coding purposes, the
- first macroblock in a slice must be coded, although the
- decoder will probably handle that case as well.
- -MBPS
- This specifies the macroblocks per slice. If left
-
- AT&T Bell Laboratories Last change: 24 February 1993 1
-
-
- MPEG(1) USER COMMANDS MPEG(1)
-
- unspecified then the number of macroblocks per slice is
- the number of macroblocks on one row of the image.
- -UTC Forces the frame number of the image to match the
- Group-of-Pictures time code. Only useful for the
- decoder.
- -a denotes the following value to be the start of the
- filename index [inclusive]. Defaults to 0.
- -b denotes the following value to be the end of the
- filename index [inclusive]. Defaults to 0.
- -d enables the decoder. The only options useful for the
- decoder are the filename specifications and the -NPS,
- -UTC commmands; the rest of the command-line informa-
- tion is used for encoding.
- -h is the horizontal size of the picture in terms of the
- luminance component, used for a non -NTSC, -CIF, -QCIF
- filesize. See the preceding note about -PF about the
- dimensions of the file relative to that of the com-
- ponent.
- -v is the vertical size of the picture in terms of the
- luminance component, used for a non -NTSC, -CIF, -QCIF
- filesize. See the preceding note about -PF about the
- dimensions of the file relative to that of the com-
- ponent.
- -f is the number of interpolated frames between each
- intra/predicted frame. FrameInterval-1 is the number
- of interpolated frames within each frame interval.
- -g is the number of frame intervals per group-of-pictures.
- With a group interval of 1 then there are no predicted
- frames. The value GroupInterval-1 is the number of
- predicted frames in each group of pictures.
- -4 is used to DC Intraframe mode where only the DC com-
- ponents of each picture block is coded.
- -i is the diameter of the motion estimation search. The
- diameter must be inclusively between 1 and 15, desig-
- nating a region from interframe only (0,0) search, to
- full search (+- 7.5, +- 7.5). The motion estimation is
- telescopic for frame distances greater than 1 (thus
- having a greater effective range).
- -o signals that the program interpreter will read the con-
- trol algorithms from the standard input.
-
- AT&T Bell Laboratories Last change: 24 February 1993 2
-
-
- MPEG(1) USER COMMANDS MPEG(1)
-
- -p specifies the picture rate by a code directly placed
- into the stream. It must be a number between 0 and 8.
- (default 5=30Hz).
- -q gives a value for the quantization not in the presence
- of rate control (rate control automatically changes the
- quantization values). If rate control is specified,
- this parameter gives a value for the initial quantiza-
- tion of the first frame (which the program usually
- takes an educated guess at).
- -r specified a rate for the coded stream. If this is
- enabled, a buffer model is used to limit the size of
- the coding stream. Note this is given in bits per
- second.
- -s specifies the filename to store the coded image. If
- unspecified it defaults to ComponentFilePrefix0.mpg.
- -v designates that quantization decisions are to be writ-
- ten to standard output. This is the verbose mode.
- -x gives a target filesize for the compressed stream. This
- overrides the rate option -r, if specified. This is
- specified in bits. The actual implementation of this
- technique is through calculating the equivalent bit-
- rate. Since the buffer usually has some contents at the
- end of coding, the final filesize is larger than actu-
- ally designated.
- -y enables the double-precision floating point Reference
- DCT. The default is the Chen DCT.
- -z denotes the component file suffixes in sequential
- order. For example
- -z .y.clr -z .u.clr -z .v.clr indicates that the lumi-
- nance and the two chrominance files end with a suffix
- of .y.clr, .u.clr, and .v.clr, in that order. If
- unspecified, the suffixes default to .Y, U, and .V.
- ComponentFilePrefixn
- must be specified. In general, the other component
- files share the same prefix and will default to Com-
- ponentFilePrefix1 if not explicitly specified. However,
- in some cases the prefix is what changes in the file
- and we can specify this individually.
-
- EXAMPLES
- To encode a set of raw raster scan YUV files with dimension
- 352x240 Y, 176x120 U,V, with labels, hello0.Y hello0.U
- hello0.V, hello1.Y hello1.U hello1.V, ..., hello12.Y
- hello12.U hello12.V through the mpeg encoder, type
-
- AT&T Bell Laboratories Last change: 24 February 1993 3
-
-
- MPEG(1) USER COMMANDS MPEG(1)
-
- mpeg -a 0 -b 12 hello -s hello.mpg
- This creates the output file hello.mpg. In order to decode
- such a file into a sequence of image files with prefix good-
- bye, type
- mpeg -d -s hello.mpg goodbye
- The output will be placed in the files goodbye0.Y goodbye0.U
- goodbye0.V, goodbye1.Y goodbye1.U goodbye1.V, ...,
- goodbye12.Y goodbye12.U goodbye12.V. These image sequences
- can be displayed by the cv program available by anonymous
- ftp from havefun.stanford.edu:pub/cv/CVv1.1.tar.Z. There are
- more options within an internal program interpreter. Please
- see the accompanying documentation in doc.ps for more
- details.
-
- FTP
- mpeg is available by anonymous ftp from
- havefun.stanford.edu:pub/mpeg/MPEGv1.1.tar.Z.
-
- BUGS
- Somewhat slower than many commercial implementations.
- Please inform the author at achung@cs.stanford.edu if any
- bugs are found.
-
- AUTHOR
- Andy Hung
-
- AT&T Bell Laboratories Last change: 24 February 1993 4
-