Section: User Commands (1)
Updated: July 12, 2000
pnmtofiasco - Convert a portable anymap to FIASCO compressed file
pnmtofiasco [option]... [filename]...
pnmtofiasco compresses the named pbm, pgm, or ppm image files, or Standard Input if no file is named, and produces a FIASCO file on Standard Output.
All option names may be abbreviated; for example, --optimize may be written --optim or --opt. For most options a one letter short option is provided. Mandatory or optional arguments to long options are mandatory or optional for short options, too. Both short and long options are case sensitive.
The basic options are:
Templates are useful when compressing video streams: e.g., if you specify the template img0[12-01-2].pgm, then pnmtofiasco compresses the images img012.pgm, img010.pgm, ..., img002.pgm.
If name is a relative path, pnmtofiasco searches for the image files in the current directory and in the (colon-separated) list of directories given by the environment variable FIASCO_IMAGES.
If name is a relative path and the environment variable FIASCO_DATA is a (colon-separated) list of directories, then pnmtofiasco writes the output file to the first (writable) directory of this list. Otherwise, pnmtofiasco write it to the current directory.
0: no progress meter
1: RPM style progress bar using 50 hash marks
2: percentage meter
1) Global ressource file /etc/system.fiascorc
3) command line
:-h, --info <DD CLASS="c1|Print brief help, then exit.:
:-H, --help <DD CLASS="c1|Print detailed help, then exit.:
:-P, --prediction <DD CLASS="c1|Use additional predictive coding. If this optimization is enabled then the image is compressed in two steps. In the first step, a coarse approximation of the image is computed using large unichrome blocks. Finally, the delta image is computed and the prediction error is approximated using the standard FIASCO algorithm.:
desc-variance: Tiles with small variances are processed first.
asc-variance: Tiles with large variances are processed first.
desc-spiral: Tiles are process in spiral order starting in the middle.
asc-spiral: Tiles are process in spiral order starting at the border.
:-2, --half-pixel <DD CLASS="c1|Use half pixel precise motion compensation.:
I: intra frame, i.e., no motion compensated prediction is used at all.
P: predicted frame, i.e., a previously encoded frame is used for prediction (forward prediction).
B: bidirectional predicted frame, i.e., not only a previously shown frame but also a frame of the future is used for prediction (forward, backward or interpolated prediction).
:--cross-B-search <DD CLASS="c1|Instead of using exhaustive search the "Cross-B-Search" algorithm is used to find the best interpolated prediction of B-frames.:
:--B-as-past-ref <DD CLASS="c1|Also use previously encoded B-frames when prediction the current frame. If this option is not set, only I- and P-frames are used to predict the current frame.:
Ullrich Hafner, Juergen Albert, Stefan Frank, and Michael Unger. Weighted Finite Automata for Video Compression, IEEE Journal on Selected Areas In Communications, January 1998
Ullrich Hafner. Low Bit-Rate Image and Video Coding with Weighted Finite Automata, Ph.D. thesis, Mensch & Buch Verlag, ISBN 3-89820-002-7, October 1999.
Ullrich Hafner <[email protected]>
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