pnmtofiasco Man page

pnmmtofiasco(1) General Commands Manual pnmmtofiasco(1)

NAME

pnmtofiasco – Convert a portable anymap to FIASCO compressed file

SYNOPSIS

pnmtofiasco [option]… [filename]…

DESCRIPTION

pnmtofiasco compresses the named pbm, pgm, or ppm image files, or Stan‐
dard Input if no file is named, and produces a FIASCO file on Standard
Output.

OPTIONS

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 manda‐
tory or optional for short options, too. Both short and long options
are case sensitive.

The basic options are:

-i name, –input-name=name
Compress the named images, not Standard Input. If name is -,
read Standard Input. name has to be either an image filename or
a template of the form:

prefix[start-end{+,-}step]suffix

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.

-o output-file, –output-name=name
Write FIASCO output to the named file, not to Standard Output.

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.

-q N, –quality=N
Set quality of compression to N. Quality is 1 (worst) to 100
(best); default is 20.

-v, –version
Print pnmtofiasco version number, then exit.

-V N, –verbose N
Set level of verbosity to N. Level is 0 (no output at all), 1
(show progress meter), or 2 (show detailed compression statis‐
tics); default is 1.

-B N, –progress-meter N
Set type of progress-meter to N. The following types are avail‐
able; default is 1:

0: no progress meter

1: RPM style progress bar using 50 hash marks

2: percentage meter

-f name, –config=name
Load parameter file name to initialize the options of pnmtofi‐
asco. See file system.fiascorc for an example of the syntax.
Options of pnmtofiasco are set by any of the following methods
(in the specified order):

1) Global ressource file /etc/system.fiascorc

2) $HOME/.fiascorc

3) command line

4) –config=name

-h, –info
Print brief help, then exit.

-H, –help
Print detailed help, then exit.

The options for advanced users are:

-b name, –basis-name=name
Preload compression basis name into FIASCO. The basis name pro‐
vides the initial compression dictionary. Either use one of the
files “small.fco”, “medium.fco”, or “large.fco” that come with
pnmtofiasco or create a new ASCII basis file.

-z N, –optimize=N Set optimization level to
N. Level is 0 (fastes) to 3 (slowest); default is 1. Be warned,
the encoding time dramatically increased when N=2 or N=3 while
the compression performance only slightly improves.

-P, –prediction
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.

-D N, –dictionary-size=N
Set size of dictionary that is used when coding the luminance
band to N; default is 10000, i.e., the dictionary is not
restricted.

-C N, –chroma-dictionary=N
Set size of dictionary that is used when coding chroma bands to
N; default is 40.

-Q N, –chroma-qfactor=N
Reduce the quality of chroma band compression N-times with
respect to the user defined quality q of the luminance band com‐
pression (–quality=q); default is 2.

-t N, –tiling-exponent=N
Subdivide the image into 2^N tiles prior coding; default is 4,
i.e. the image is subdivided into 16 tiles. The processing order
of the individual tiles is defined by the option –tiling-
method=name.

-T name, –tiling-method=name
Order the individual image tiles (the image is subdivided into;
see option –tiling-exponent=N) by method name; default is
“desc-variance”.

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.

–rpf-mantissa=N
Use N mantissa bits for quantized coefficients.

–dc-rpf-mantissa=N
Use N mantissa bits for quantized DC coefficients.

–rpf-range=N
Coefficients outside the quantization interval [-N,+N] are set
to zero.

–dc-rpf-range=N
DC coefficients outside the quantization interval [-N,+N] are
set to zero.

Additional options for video compression are:

-s N, –smooth=N
Smooth decompressed reference frames along the partitioning bor‐
ders by the given amount N. N is 0 (no smoothing) to 100;
default is 70. This factor is stored in the FIASCO file.

-m N, –min-level=N
Start prediction (motion compensated prediction or additional
prediction) on block level N; default is level 6. I.e., motion
compensation is applied to all image blocks of at least 8×8 pix‐
els (binary tree level N=6), 16×8 (N=7), 16×16 (N=8), etc.

-M N, –max-level=N
Stop prediction (motion compensated prediction or additional
prediction) on block level N; default is level 10. I.e., motion
compensation is applied to all image blocks of at most 16×16
pixels (N=8), 32×16 (N=9), 32×32 (N=10), etc.

-2, –half-pixel
Use half pixel precise motion compensation.

-F N, –fps=N
Set number of frames per second to N. This value is stored in
the FIASCO output file and is used in the decoder dfiasco(1) to
control the framerate.

-p type, –pattern=type
Defines the type of inter frame compression which should be
applied to individual frames of a video stream. type is a
sequence of characters; default is “IPPPPPPPPP”. Element N
defines the type of predicting which should be used for frame N;
the frame type pattern is periodically extended. Valid charac‐
ters are:

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 predic‐
tion (forward, backward or interpolated prediction).

–cross-B-search
Instead of using exhaustive search the “Cross-B-Search” algo‐
rithm is used to find the best interpolated prediction of B-
frames.

–B-as-past-ref
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.

EXAMPLES
pnmtofiasco < foo.ppm >foo.wfa
Compress the still image “foo.ppm” to the FIASCO file “foo.wfa”
using the default options.

pnmtofiasco -2 -p “IBBPBBPBB” -fps 15 -o video.wfa foo0*.ppm
Compress the video frames “foo0*.ppm” to the FIASCO file
“video.wfa” using half pixel precise motion compensation at a
frame rate of 15 frames per second. Intra frame 1 is used to
predict P-frame 4, frames 1 and 4 are used to predict B-frames 2
and 3, and so on. Frame 10 is again an intra-frame.

FILES
/etc/system.fiascorc
The systemwide initialization file.
$HOME/.fiascorc
The personal initialization file.

ENVIRONMENT
FIASCO_IMAGES
Search path for image files. Default is “./”.
FIASCO_DATA
Search and save path for FIASCO files. Default is “./”.

SEE ALSO

fiascotopnm, ppmtojpeg, pnmtojbig(1), ppmtogif, pnm(5)

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.

AUTHOR

Ullrich Hafner

July 12, 2000 pnmmtofiasco(1)

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