ref: 310af750eb5726b4143a43208f2bc03677c6f5db
dir: /silk/SKP_Silk_array_maxabs.c/
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/* *
* SKP_Silk_int16_array_maxabs.c *
* *
* Function that returns the maximum absolut value of *
* the input vector *
* *
* Copyright 2006 (c), Skype Limited *
* Date: 060221 *
* */
#include "SKP_Silk_SigProc_FIX.h"
/* Function that returns the maximum absolut value of the input vector */
SKP_int16 SKP_Silk_int16_array_maxabs( /* O Maximum absolute value, max: 2^15-1 */
const SKP_int16 *vec, /* I Input vector [len] */
const SKP_int32 len /* I Length of input vector */
)
{
SKP_int32 max = 0, i, lvl = 0, ind;
if( len == 0 ) return 0;
ind = len - 1;
max = SKP_SMULBB( vec[ ind ], vec[ ind ] );
for( i = len - 2; i >= 0; i-- ) {
lvl = SKP_SMULBB( vec[ i ], vec[ i ] );
if( lvl > max ) {
max = lvl;
ind = i;
}
}
/* Do not return 32768, as it will not fit in an int16 so may lead to problems later on */
if( max >= 1073676289 ) { // (2^15-1)^2 = 1073676289
return( SKP_int16_MAX );
} else {
if( vec[ ind ] < 0 ) {
return( -vec[ ind ] );
} else {
return( vec[ ind ] );
}
}
}