mirror of https://git.ffmpeg.org/ffmpeg.git
Small simplifications to subband coefficient handling and use av_random().
Patch by Ian Braithwaite ian .. braithwaite ... dk Originally committed as revision 8456 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Ian Braithwaite
Benjamin Larsson
parent
0ec4bc6a27
commit
058ee0cf95
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@ -52,6 +52,7 @@
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#include "dsputil.h"
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#include "common.h"
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#include "bytestream.h"
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#include "random.h"
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#include "cookdata.h"
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@ -87,7 +88,7 @@ typedef struct {
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int bits_per_subpacket;
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int cookversion;
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/* states */
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int random_state;
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AVRandomState random_state;
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/* transform data */
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MDCTContext mdct_ctx;
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@ -373,22 +374,6 @@ static void decode_envelope(COOKContext *q, int* quant_index_table) {
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}
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}
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/**
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* Create the quant value table.
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*
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* @param q pointer to the COOKContext
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* @param quant_value_table pointer to the array
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*/
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static void inline dequant_envelope(COOKContext *q, int* quant_index_table,
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float* quant_value_table){
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int i;
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for(i=0 ; i < q->total_subbands ; i++){
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quant_value_table[i] = q->rootpow2tab[quant_index_table[i]+63];
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}
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}
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/**
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* Calculate the category and category_index vector.
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*
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@ -536,33 +521,28 @@ static void inline expand_category(COOKContext *q, int* category,
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*
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* @param q pointer to the COOKContext
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* @param index index
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* @param band current subband
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* @param quant_value_table pointer to the array
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* @param quant_index quantisation index
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* @param subband_coef_index array of indexes to quant_centroid_tab
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* @param subband_coef_sign signs of coefficients
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* @param mlt_buffer pointer to the mlt buffer
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* @param mlt_p pointer into the mlt buffer
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*/
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static void scalar_dequant(COOKContext *q, int index, int band,
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float* quant_value_table, int* subband_coef_index,
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int* subband_coef_sign, float* mlt_buffer){
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static void scalar_dequant(COOKContext *q, int index, int quant_index,
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int* subband_coef_index, int* subband_coef_sign,
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float* mlt_p){
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int i;
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float f1;
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for(i=0 ; i<SUBBAND_SIZE ; i++) {
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if (subband_coef_index[i]) {
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if (subband_coef_sign[i]) {
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f1 = -quant_centroid_tab[index][subband_coef_index[i]];
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} else {
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f1 = quant_centroid_tab[index][subband_coef_index[i]];
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}
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f1 = quant_centroid_tab[index][subband_coef_index[i]];
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if (subband_coef_sign[i]) f1 = -f1;
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} else {
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/* noise coding if subband_coef_index[i] == 0 */
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q->random_state = q->random_state * 214013 + 2531011; //typical RNG numbers
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f1 = randsign[(q->random_state/0x1000000)&1] * dither_tab[index]; //>>31
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f1 = dither_tab[index];
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if (av_random(&q->random_state) < 0x80000000) f1 = -f1;
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}
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mlt_buffer[band*20+ i] = f1 * quant_value_table[band];
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mlt_p[i] = f1 * q->rootpow2tab[quant_index+63];
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}
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}
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/**
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@ -618,13 +598,13 @@ static int unpack_SQVH(COOKContext *q, int category, int* subband_coef_index,
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*
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* @param q pointer to the COOKContext
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* @param category pointer to the category array
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* @param quant_value_table pointer to the array
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* @param quant_index_table pointer to the array
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* @param mlt_buffer pointer to mlt coefficients
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*/
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static void decode_vectors(COOKContext* q, int* category,
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float* quant_value_table, float* mlt_buffer){
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int *quant_index_table, float* mlt_buffer){
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/* A zero in this table means that the subband coefficient is
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random noise coded. */
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int subband_coef_index[SUBBAND_SIZE];
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@ -646,8 +626,9 @@ static void decode_vectors(COOKContext* q, int* category,
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memset(subband_coef_index, 0, sizeof(subband_coef_index));
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memset(subband_coef_sign, 0, sizeof(subband_coef_sign));
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}
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scalar_dequant(q, index, band, quant_value_table, subband_coef_index,
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subband_coef_sign, mlt_buffer);
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scalar_dequant(q, index, quant_index_table[band],
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subband_coef_index, subband_coef_sign,
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&mlt_buffer[band * 20]);
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}
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if(q->total_subbands*SUBBAND_SIZE >= q->samples_per_channel){
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@ -667,20 +648,17 @@ static void decode_vectors(COOKContext* q, int* category,
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static void mono_decode(COOKContext *q, float* mlt_buffer) {
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int category_index[128];
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float quant_value_table[102];
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int quant_index_table[102];
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int category[128];
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memset(&category, 0, 128*sizeof(int));
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memset(&quant_value_table, 0, 102*sizeof(int));
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memset(&category_index, 0, 128*sizeof(int));
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decode_envelope(q, quant_index_table);
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q->num_vectors = get_bits(&q->gb,q->log2_numvector_size);
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dequant_envelope(q, quant_index_table, quant_value_table);
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categorize(q, quant_index_table, category, category_index);
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expand_category(q, category, category_index);
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decode_vectors(q, category, quant_value_table, mlt_buffer);
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decode_vectors(q, category, quant_index_table, mlt_buffer);
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}
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@ -1035,8 +1013,8 @@ static int cook_decode_init(AVCodecContext *avctx)
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q->nb_channels = avctx->channels;
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q->bit_rate = avctx->bit_rate;
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/* Initialize state. */
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q->random_state = 1;
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/* Initialize RNG. */
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av_init_random(1, &q->random_state);
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/* Initialize extradata related variables. */
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q->samples_per_channel = q->samples_per_frame / q->nb_channels;
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