fiasco(3) Fractal Image And Sequence COdec fiasco(3)NAME
fiasco_d_options_new, fiasco_d_options_set_magnification,
fiasco_d_options_delete, fiasco_d_options_set_smoothing
fiasco_d_options_set_4_2_0_format - define additional options of FIASCO
decoder
SYNOPSIS
#include <fiasco.h>
fiasco_d_options_t *
fiasco_d_options_new
(void);
void
fiasco_d_options_delete
(fiasco_d_options_t * options);
int
fiasco_d_options_set_4_2_0_format
(fiasco_d_options_t * options,
int format);
int
fiasco_d_options_set_magnification
(fiasco_d_options_t * options,
int level);
int
fiasco_d_options_set_smoothing
(fiasco_d_options_t * options,
unsigned smoothing);
DESCRIPTION
The fiasco_d_options_new() function allocates and initializes a FIASCO
options object which is used to control additional decompression param‐
eters.
Conversely, the function fiasco_d_options_delete() discards the given
FIASCO decoder options object.
Several member functions are available to modify the default behavior
of the FIASCO decoder.
fiasco_d_options_set_smoothing() sets the smoothing-percentage along
partitioning borders when the images are regenerated; default is 70.
fiasco_d_options_set_magnification() sets the magnification of the
regenerated image; default is 0, i.e., the image geometry is not
changed.
fiasco_d_options_set_4_2_0_format() defines whether the decoder should
use the default 4:4:4 format or the 4:2:0 format. The latter one sig‐
nificantly reduces the decoding time at the cost of some additional
blocking artefacts.
ARGUMENTS
options
This object encapsulates various decoding parameters.
smoothing
This percentage (range is 0 - i.e., no smoothing - to 100)
defines how much the regenerated image is smoothed along the
partitioning borders.
level This value gives the magnification of the decoded image with
respect to the original size. Positive values increase and nega‐
tive values decrease the width and height of the image by a fac‐
tor of 2^abs(level).
format If format is 0 then the 4:4:4 color image format is used, i.e.,
the chroma channel are of the same size as the luminance. Other‐
wise, the 4:2:0 format is used. Then, width and height of each
chroma channel is only one half of the width and height of the
luminance.
RETURN VALUES
The function fiasco_d_options_new() returns a pointer to the newly
allocated decoder option object. If an error has been catched, a NULL
pointer is returned.
All set functions return 1 on success and 0 if an error has been
catched.
In case of an error, use the function fiasco_get_error_message(3) to
get a string with the last error message of FIASCO.
SEE ALSOfiasco_decoder(3), fiasco_coder(3)
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 <hafner@bigfoot.de>
FIASCO April, 2000 fiasco(3)