ardecode2 Arithmetic decoding of a compressed fimage
ardecode2 [-i] [-r NRow] [-n NSymbol] [-c Cap_Histo] [-p Predic] [-h Fsignal] Cimage . Fimage
-i : Do not print info on decoding process
-r NRow : Number of rows in output Fimage
-n NSymbol : Number of different symbols in source
-c Cap_Histo : Capacity of histogram
-p Predic : 0 : no prediction, 1 : predictive encoding has been used, default : info is in header
-h Fsignal : Histogram model for input symbols (fsignal)
Cimage : Input string of symbols (cimage)
. (screen output) : Rate of output
Fimage : Output string of codewords (fimage)
void ardecode2 (Print , NRow , NSymb , Cap_Histo , Predic , Histo , Input , Rate , Output )
int *Print ;
int *NRow ;
int *NSymb ;
long *Cap_Histo ;
int *Predic ;
Fsignal Histo ;
Cimage Input ;
double *Rate ;
Fimage Output ;
This module gets back a list of symbols which have been arithmetically encoded with the arithm_encode2 module according to the algorithm described in [WNC87].
The -r option enables to specify the number of rows in the Output fimage. If it is not selected, then it is computed in order that the blank space after the list of symbols is as small as possible.
The -n option enables to specify the size of the output symbol alphabet. This option should be selected if the -H option was not activated at the encoding phase. Otherwise this information is included in the header.
The -c option has the same meaning as for arithm_encode2. It should be tuned in the same way as in the encoding phase.
The -p option tells wether predictive encoding has been used or not during the encoding phase. Predic equal to 0 (resp. 1) means that encoding was not (resp. was) predictive. If this option is not activated, then it means that the information is contained in the header and thus that the -H option has been activated during the encoding phase.
If the -h option is activated, this means that the histogram contained in the fsignal Histo has been used as the fixed source distribution histogram during the encoding phase. Thus it should be used again for decoding. This option should be tuned in the same way as in the encoding phase.
Last Modification date : Tue Jul 2 19:23:19 2002