Libav 0.7.1
libavcodec/cook.c
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00001 /*
00002  * COOK compatible decoder
00003  * Copyright (c) 2003 Sascha Sommer
00004  * Copyright (c) 2005 Benjamin Larsson
00005  *
00006  * This file is part of Libav.
00007  *
00008  * Libav is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * Libav is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with Libav; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00045 #include <math.h>
00046 #include <stddef.h>
00047 #include <stdio.h>
00048 
00049 #include "libavutil/lfg.h"
00050 #include "libavutil/random_seed.h"
00051 #include "avcodec.h"
00052 #include "get_bits.h"
00053 #include "dsputil.h"
00054 #include "bytestream.h"
00055 #include "fft.h"
00056 #include "libavutil/audioconvert.h"
00057 #include "sinewin.h"
00058 
00059 #include "cookdata.h"
00060 
00061 /* the different Cook versions */
00062 #define MONO            0x1000001
00063 #define STEREO          0x1000002
00064 #define JOINT_STEREO    0x1000003
00065 #define MC_COOK         0x2000000   //multichannel Cook, not supported
00066 
00067 #define SUBBAND_SIZE    20
00068 #define MAX_SUBPACKETS   5
00069 
00070 typedef struct {
00071     int *now;
00072     int *previous;
00073 } cook_gains;
00074 
00075 typedef struct {
00076     int                 ch_idx;
00077     int                 size;
00078     int                 num_channels;
00079     int                 cookversion;
00080     int                 samples_per_frame;
00081     int                 subbands;
00082     int                 js_subband_start;
00083     int                 js_vlc_bits;
00084     int                 samples_per_channel;
00085     int                 log2_numvector_size;
00086     unsigned int        channel_mask;
00087     VLC                 ccpl;                 
00088     int                 joint_stereo;
00089     int                 bits_per_subpacket;
00090     int                 bits_per_subpdiv;
00091     int                 total_subbands;
00092     int                 numvector_size;       
00093 
00094     float               mono_previous_buffer1[1024];
00095     float               mono_previous_buffer2[1024];
00097     cook_gains          gains1;
00098     cook_gains          gains2;
00099     int                 gain_1[9];
00100     int                 gain_2[9];
00101     int                 gain_3[9];
00102     int                 gain_4[9];
00103 } COOKSubpacket;
00104 
00105 typedef struct cook {
00106     /*
00107      * The following 5 functions provide the lowlevel arithmetic on
00108      * the internal audio buffers.
00109      */
00110     void (* scalar_dequant)(struct cook *q, int index, int quant_index,
00111                             int* subband_coef_index, int* subband_coef_sign,
00112                             float* mlt_p);
00113 
00114     void (* decouple) (struct cook *q,
00115                        COOKSubpacket *p,
00116                        int subband,
00117                        float f1, float f2,
00118                        float *decode_buffer,
00119                        float *mlt_buffer1, float *mlt_buffer2);
00120 
00121     void (* imlt_window) (struct cook *q, float *buffer1,
00122                           cook_gains *gains_ptr, float *previous_buffer);
00123 
00124     void (* interpolate) (struct cook *q, float* buffer,
00125                           int gain_index, int gain_index_next);
00126 
00127     void (* saturate_output) (struct cook *q, int chan, int16_t *out);
00128 
00129     AVCodecContext*     avctx;
00130     GetBitContext       gb;
00131     /* stream data */
00132     int                 nb_channels;
00133     int                 bit_rate;
00134     int                 sample_rate;
00135     int                 num_vectors;
00136     int                 samples_per_channel;
00137     /* states */
00138     AVLFG               random_state;
00139 
00140     /* transform data */
00141     FFTContext          mdct_ctx;
00142     float*              mlt_window;
00143 
00144     /* VLC data */
00145     VLC                 envelope_quant_index[13];
00146     VLC                 sqvh[7];          //scalar quantization
00147 
00148     /* generatable tables and related variables */
00149     int                 gain_size_factor;
00150     float               gain_table[23];
00151 
00152     /* data buffers */
00153 
00154     uint8_t*            decoded_bytes_buffer;
00155     DECLARE_ALIGNED(32, float, mono_mdct_output)[2048];
00156     float               decode_buffer_1[1024];
00157     float               decode_buffer_2[1024];
00158     float               decode_buffer_0[1060]; /* static allocation for joint decode */
00159 
00160     const float         *cplscales[5];
00161     int                 num_subpackets;
00162     COOKSubpacket       subpacket[MAX_SUBPACKETS];
00163 } COOKContext;
00164 
00165 static float     pow2tab[127];
00166 static float rootpow2tab[127];
00167 
00168 /*************** init functions ***************/
00169 
00170 /* table generator */
00171 static av_cold void init_pow2table(void){
00172     int i;
00173     for (i=-63 ; i<64 ; i++){
00174             pow2tab[63+i]=     pow(2, i);
00175         rootpow2tab[63+i]=sqrt(pow(2, i));
00176     }
00177 }
00178 
00179 /* table generator */
00180 static av_cold void init_gain_table(COOKContext *q) {
00181     int i;
00182     q->gain_size_factor = q->samples_per_channel/8;
00183     for (i=0 ; i<23 ; i++) {
00184         q->gain_table[i] = pow(pow2tab[i+52] ,
00185                                (1.0/(double)q->gain_size_factor));
00186     }
00187 }
00188 
00189 
00190 static av_cold int init_cook_vlc_tables(COOKContext *q) {
00191     int i, result;
00192 
00193     result = 0;
00194     for (i=0 ; i<13 ; i++) {
00195         result |= init_vlc (&q->envelope_quant_index[i], 9, 24,
00196             envelope_quant_index_huffbits[i], 1, 1,
00197             envelope_quant_index_huffcodes[i], 2, 2, 0);
00198     }
00199     av_log(q->avctx,AV_LOG_DEBUG,"sqvh VLC init\n");
00200     for (i=0 ; i<7 ; i++) {
00201         result |= init_vlc (&q->sqvh[i], vhvlcsize_tab[i], vhsize_tab[i],
00202             cvh_huffbits[i], 1, 1,
00203             cvh_huffcodes[i], 2, 2, 0);
00204     }
00205 
00206     for(i=0;i<q->num_subpackets;i++){
00207         if (q->subpacket[i].joint_stereo==1){
00208             result |= init_vlc (&q->subpacket[i].ccpl, 6, (1<<q->subpacket[i].js_vlc_bits)-1,
00209                 ccpl_huffbits[q->subpacket[i].js_vlc_bits-2], 1, 1,
00210                 ccpl_huffcodes[q->subpacket[i].js_vlc_bits-2], 2, 2, 0);
00211             av_log(q->avctx,AV_LOG_DEBUG,"subpacket %i Joint-stereo VLC used.\n",i);
00212         }
00213     }
00214 
00215     av_log(q->avctx,AV_LOG_DEBUG,"VLC tables initialized.\n");
00216     return result;
00217 }
00218 
00219 static av_cold int init_cook_mlt(COOKContext *q) {
00220     int j;
00221     int mlt_size = q->samples_per_channel;
00222 
00223     if ((q->mlt_window = av_malloc(sizeof(float)*mlt_size)) == 0)
00224       return -1;
00225 
00226     /* Initialize the MLT window: simple sine window. */
00227     ff_sine_window_init(q->mlt_window, mlt_size);
00228     for(j=0 ; j<mlt_size ; j++)
00229         q->mlt_window[j] *= sqrt(2.0 / q->samples_per_channel);
00230 
00231     /* Initialize the MDCT. */
00232     if (ff_mdct_init(&q->mdct_ctx, av_log2(mlt_size)+1, 1, 1.0)) {
00233       av_free(q->mlt_window);
00234       return -1;
00235     }
00236     av_log(q->avctx,AV_LOG_DEBUG,"MDCT initialized, order = %d.\n",
00237            av_log2(mlt_size)+1);
00238 
00239     return 0;
00240 }
00241 
00242 static const float *maybe_reformat_buffer32 (COOKContext *q, const float *ptr, int n)
00243 {
00244     if (1)
00245         return ptr;
00246 }
00247 
00248 static av_cold void init_cplscales_table (COOKContext *q) {
00249     int i;
00250     for (i=0;i<5;i++)
00251         q->cplscales[i] = maybe_reformat_buffer32 (q, cplscales[i], (1<<(i+2))-1);
00252 }
00253 
00254 /*************** init functions end ***********/
00255 
00256 #define DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
00257 #define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
00258 
00280 static inline int decode_bytes(const uint8_t* inbuffer, uint8_t* out, int bytes){
00281     int i, off;
00282     uint32_t c;
00283     const uint32_t* buf;
00284     uint32_t* obuf = (uint32_t*) out;
00285     /* FIXME: 64 bit platforms would be able to do 64 bits at a time.
00286      * I'm too lazy though, should be something like
00287      * for(i=0 ; i<bitamount/64 ; i++)
00288      *     (int64_t)out[i] = 0x37c511f237c511f2^av_be2ne64(int64_t)in[i]);
00289      * Buffer alignment needs to be checked. */
00290 
00291     off = (intptr_t)inbuffer & 3;
00292     buf = (const uint32_t*) (inbuffer - off);
00293     c = av_be2ne32((0x37c511f2 >> (off*8)) | (0x37c511f2 << (32-(off*8))));
00294     bytes += 3 + off;
00295     for (i = 0; i < bytes/4; i++)
00296         obuf[i] = c ^ buf[i];
00297 
00298     return off;
00299 }
00300 
00305 static av_cold int cook_decode_close(AVCodecContext *avctx)
00306 {
00307     int i;
00308     COOKContext *q = avctx->priv_data;
00309     av_log(avctx,AV_LOG_DEBUG, "Deallocating memory.\n");
00310 
00311     /* Free allocated memory buffers. */
00312     av_free(q->mlt_window);
00313     av_free(q->decoded_bytes_buffer);
00314 
00315     /* Free the transform. */
00316     ff_mdct_end(&q->mdct_ctx);
00317 
00318     /* Free the VLC tables. */
00319     for (i=0 ; i<13 ; i++) {
00320         free_vlc(&q->envelope_quant_index[i]);
00321     }
00322     for (i=0 ; i<7 ; i++) {
00323         free_vlc(&q->sqvh[i]);
00324     }
00325     for (i=0 ; i<q->num_subpackets ; i++) {
00326         free_vlc(&q->subpacket[i].ccpl);
00327     }
00328 
00329     av_log(avctx,AV_LOG_DEBUG,"Memory deallocated.\n");
00330 
00331     return 0;
00332 }
00333 
00341 static void decode_gain_info(GetBitContext *gb, int *gaininfo)
00342 {
00343     int i, n;
00344 
00345     while (get_bits1(gb)) {}
00346     n = get_bits_count(gb) - 1;     //amount of elements*2 to update
00347 
00348     i = 0;
00349     while (n--) {
00350         int index = get_bits(gb, 3);
00351         int gain = get_bits1(gb) ? get_bits(gb, 4) - 7 : -1;
00352 
00353         while (i <= index) gaininfo[i++] = gain;
00354     }
00355     while (i <= 8) gaininfo[i++] = 0;
00356 }
00357 
00365 static void decode_envelope(COOKContext *q, COOKSubpacket *p, int* quant_index_table) {
00366     int i,j, vlc_index;
00367 
00368     quant_index_table[0]= get_bits(&q->gb,6) - 6;       //This is used later in categorize
00369 
00370     for (i=1 ; i < p->total_subbands ; i++){
00371         vlc_index=i;
00372         if (i >= p->js_subband_start * 2) {
00373             vlc_index-=p->js_subband_start;
00374         } else {
00375             vlc_index/=2;
00376             if(vlc_index < 1) vlc_index = 1;
00377         }
00378         if (vlc_index>13) vlc_index = 13;           //the VLC tables >13 are identical to No. 13
00379 
00380         j = get_vlc2(&q->gb, q->envelope_quant_index[vlc_index-1].table,
00381                      q->envelope_quant_index[vlc_index-1].bits,2);
00382         quant_index_table[i] = quant_index_table[i-1] + j - 12;    //differential encoding
00383     }
00384 }
00385 
00395 static void categorize(COOKContext *q, COOKSubpacket *p, int* quant_index_table,
00396                        int* category, int* category_index){
00397     int exp_idx, bias, tmpbias1, tmpbias2, bits_left, num_bits, index, v, i, j;
00398     int exp_index2[102];
00399     int exp_index1[102];
00400 
00401     int tmp_categorize_array[128*2];
00402     int tmp_categorize_array1_idx=p->numvector_size;
00403     int tmp_categorize_array2_idx=p->numvector_size;
00404 
00405     bits_left =  p->bits_per_subpacket - get_bits_count(&q->gb);
00406 
00407     if(bits_left > q->samples_per_channel) {
00408         bits_left = q->samples_per_channel +
00409                     ((bits_left - q->samples_per_channel)*5)/8;
00410         //av_log(q->avctx, AV_LOG_ERROR, "bits_left = %d\n",bits_left);
00411     }
00412 
00413     memset(&exp_index1,0,102*sizeof(int));
00414     memset(&exp_index2,0,102*sizeof(int));
00415     memset(&tmp_categorize_array,0,128*2*sizeof(int));
00416 
00417     bias=-32;
00418 
00419     /* Estimate bias. */
00420     for (i=32 ; i>0 ; i=i/2){
00421         num_bits = 0;
00422         index = 0;
00423         for (j=p->total_subbands ; j>0 ; j--){
00424             exp_idx = av_clip((i - quant_index_table[index] + bias) / 2, 0, 7);
00425             index++;
00426             num_bits+=expbits_tab[exp_idx];
00427         }
00428         if(num_bits >= bits_left - 32){
00429             bias+=i;
00430         }
00431     }
00432 
00433     /* Calculate total number of bits. */
00434     num_bits=0;
00435     for (i=0 ; i<p->total_subbands ; i++) {
00436         exp_idx = av_clip((bias - quant_index_table[i]) / 2, 0, 7);
00437         num_bits += expbits_tab[exp_idx];
00438         exp_index1[i] = exp_idx;
00439         exp_index2[i] = exp_idx;
00440     }
00441     tmpbias1 = tmpbias2 = num_bits;
00442 
00443     for (j = 1 ; j < p->numvector_size ; j++) {
00444         if (tmpbias1 + tmpbias2 > 2*bits_left) {  /* ---> */
00445             int max = -999999;
00446             index=-1;
00447             for (i=0 ; i<p->total_subbands ; i++){
00448                 if (exp_index1[i] < 7) {
00449                     v = (-2*exp_index1[i]) - quant_index_table[i] + bias;
00450                     if ( v >= max) {
00451                         max = v;
00452                         index = i;
00453                     }
00454                 }
00455             }
00456             if(index==-1)break;
00457             tmp_categorize_array[tmp_categorize_array1_idx++] = index;
00458             tmpbias1 -= expbits_tab[exp_index1[index]] -
00459                         expbits_tab[exp_index1[index]+1];
00460             ++exp_index1[index];
00461         } else {  /* <--- */
00462             int min = 999999;
00463             index=-1;
00464             for (i=0 ; i<p->total_subbands ; i++){
00465                 if(exp_index2[i] > 0){
00466                     v = (-2*exp_index2[i])-quant_index_table[i]+bias;
00467                     if ( v < min) {
00468                         min = v;
00469                         index = i;
00470                     }
00471                 }
00472             }
00473             if(index == -1)break;
00474             tmp_categorize_array[--tmp_categorize_array2_idx] = index;
00475             tmpbias2 -= expbits_tab[exp_index2[index]] -
00476                         expbits_tab[exp_index2[index]-1];
00477             --exp_index2[index];
00478         }
00479     }
00480 
00481     for(i=0 ; i<p->total_subbands ; i++)
00482         category[i] = exp_index2[i];
00483 
00484     for(i=0 ; i<p->numvector_size-1 ; i++)
00485         category_index[i] = tmp_categorize_array[tmp_categorize_array2_idx++];
00486 
00487 }
00488 
00489 
00498 static inline void expand_category(COOKContext *q, int* category,
00499                                    int* category_index){
00500     int i;
00501     for(i=0 ; i<q->num_vectors ; i++){
00502         ++category[category_index[i]];
00503     }
00504 }
00505 
00517 static void scalar_dequant_float(COOKContext *q, int index, int quant_index,
00518                            int* subband_coef_index, int* subband_coef_sign,
00519                            float* mlt_p){
00520     int i;
00521     float f1;
00522 
00523     for(i=0 ; i<SUBBAND_SIZE ; i++) {
00524         if (subband_coef_index[i]) {
00525             f1 = quant_centroid_tab[index][subband_coef_index[i]];
00526             if (subband_coef_sign[i]) f1 = -f1;
00527         } else {
00528             /* noise coding if subband_coef_index[i] == 0 */
00529             f1 = dither_tab[index];
00530             if (av_lfg_get(&q->random_state) < 0x80000000) f1 = -f1;
00531         }
00532         mlt_p[i] = f1 * rootpow2tab[quant_index+63];
00533     }
00534 }
00544 static int unpack_SQVH(COOKContext *q, COOKSubpacket *p, int category, int* subband_coef_index,
00545                        int* subband_coef_sign) {
00546     int i,j;
00547     int vlc, vd ,tmp, result;
00548 
00549     vd = vd_tab[category];
00550     result = 0;
00551     for(i=0 ; i<vpr_tab[category] ; i++){
00552         vlc = get_vlc2(&q->gb, q->sqvh[category].table, q->sqvh[category].bits, 3);
00553         if (p->bits_per_subpacket < get_bits_count(&q->gb)){
00554             vlc = 0;
00555             result = 1;
00556         }
00557         for(j=vd-1 ; j>=0 ; j--){
00558             tmp = (vlc * invradix_tab[category])/0x100000;
00559             subband_coef_index[vd*i+j] = vlc - tmp * (kmax_tab[category]+1);
00560             vlc = tmp;
00561         }
00562         for(j=0 ; j<vd ; j++){
00563             if (subband_coef_index[i*vd + j]) {
00564                 if(get_bits_count(&q->gb) < p->bits_per_subpacket){
00565                     subband_coef_sign[i*vd+j] = get_bits1(&q->gb);
00566                 } else {
00567                     result=1;
00568                     subband_coef_sign[i*vd+j]=0;
00569                 }
00570             } else {
00571                 subband_coef_sign[i*vd+j]=0;
00572             }
00573         }
00574     }
00575     return result;
00576 }
00577 
00578 
00589 static void decode_vectors(COOKContext* q, COOKSubpacket* p, int* category,
00590                            int *quant_index_table, float* mlt_buffer){
00591     /* A zero in this table means that the subband coefficient is
00592        random noise coded. */
00593     int subband_coef_index[SUBBAND_SIZE];
00594     /* A zero in this table means that the subband coefficient is a
00595        positive multiplicator. */
00596     int subband_coef_sign[SUBBAND_SIZE];
00597     int band, j;
00598     int index=0;
00599 
00600     for(band=0 ; band<p->total_subbands ; band++){
00601         index = category[band];
00602         if(category[band] < 7){
00603             if(unpack_SQVH(q, p, category[band], subband_coef_index, subband_coef_sign)){
00604                 index=7;
00605                 for(j=0 ; j<p->total_subbands ; j++) category[band+j]=7;
00606             }
00607         }
00608         if(index>=7) {
00609             memset(subband_coef_index, 0, sizeof(subband_coef_index));
00610             memset(subband_coef_sign, 0, sizeof(subband_coef_sign));
00611         }
00612         q->scalar_dequant(q, index, quant_index_table[band],
00613                           subband_coef_index, subband_coef_sign,
00614                           &mlt_buffer[band * SUBBAND_SIZE]);
00615     }
00616 
00617     if(p->total_subbands*SUBBAND_SIZE >= q->samples_per_channel){
00618         return;
00619     } /* FIXME: should this be removed, or moved into loop above? */
00620 }
00621 
00622 
00630 static void mono_decode(COOKContext *q, COOKSubpacket *p, float* mlt_buffer) {
00631 
00632     int category_index[128];
00633     int quant_index_table[102];
00634     int category[128];
00635 
00636     memset(&category, 0, 128*sizeof(int));
00637     memset(&category_index, 0, 128*sizeof(int));
00638 
00639     decode_envelope(q, p, quant_index_table);
00640     q->num_vectors = get_bits(&q->gb,p->log2_numvector_size);
00641     categorize(q, p, quant_index_table, category, category_index);
00642     expand_category(q, category, category_index);
00643     decode_vectors(q, p, category, quant_index_table, mlt_buffer);
00644 }
00645 
00646 
00656 static void interpolate_float(COOKContext *q, float* buffer,
00657                         int gain_index, int gain_index_next){
00658     int i;
00659     float fc1, fc2;
00660     fc1 = pow2tab[gain_index+63];
00661 
00662     if(gain_index == gain_index_next){              //static gain
00663         for(i=0 ; i<q->gain_size_factor ; i++){
00664             buffer[i]*=fc1;
00665         }
00666         return;
00667     } else {                                        //smooth gain
00668         fc2 = q->gain_table[11 + (gain_index_next-gain_index)];
00669         for(i=0 ; i<q->gain_size_factor ; i++){
00670             buffer[i]*=fc1;
00671             fc1*=fc2;
00672         }
00673         return;
00674     }
00675 }
00676 
00686 static void imlt_window_float (COOKContext *q, float *inbuffer,
00687                                cook_gains *gains_ptr, float *previous_buffer)
00688 {
00689     const float fc = pow2tab[gains_ptr->previous[0] + 63];
00690     int i;
00691     /* The weird thing here, is that the two halves of the time domain
00692      * buffer are swapped. Also, the newest data, that we save away for
00693      * next frame, has the wrong sign. Hence the subtraction below.
00694      * Almost sounds like a complex conjugate/reverse data/FFT effect.
00695      */
00696 
00697     /* Apply window and overlap */
00698     for(i = 0; i < q->samples_per_channel; i++){
00699         inbuffer[i] = inbuffer[i] * fc * q->mlt_window[i] -
00700           previous_buffer[i] * q->mlt_window[q->samples_per_channel - 1 - i];
00701     }
00702 }
00703 
00716 static void imlt_gain(COOKContext *q, float *inbuffer,
00717                       cook_gains *gains_ptr, float* previous_buffer)
00718 {
00719     float *buffer0 = q->mono_mdct_output;
00720     float *buffer1 = q->mono_mdct_output + q->samples_per_channel;
00721     int i;
00722 
00723     /* Inverse modified discrete cosine transform */
00724     q->mdct_ctx.imdct_calc(&q->mdct_ctx, q->mono_mdct_output, inbuffer);
00725 
00726     q->imlt_window (q, buffer1, gains_ptr, previous_buffer);
00727 
00728     /* Apply gain profile */
00729     for (i = 0; i < 8; i++) {
00730         if (gains_ptr->now[i] || gains_ptr->now[i + 1])
00731             q->interpolate(q, &buffer1[q->gain_size_factor * i],
00732                            gains_ptr->now[i], gains_ptr->now[i + 1]);
00733     }
00734 
00735     /* Save away the current to be previous block. */
00736     memcpy(previous_buffer, buffer0, sizeof(float)*q->samples_per_channel);
00737 }
00738 
00739 
00748 static void decouple_info(COOKContext *q, COOKSubpacket *p, int* decouple_tab){
00749     int length, i;
00750 
00751     if(get_bits1(&q->gb)) {
00752         if(cplband[p->js_subband_start] > cplband[p->subbands-1]) return;
00753 
00754         length = cplband[p->subbands-1] - cplband[p->js_subband_start] + 1;
00755         for (i=0 ; i<length ; i++) {
00756             decouple_tab[cplband[p->js_subband_start] + i] = get_vlc2(&q->gb, p->ccpl.table, p->ccpl.bits, 2);
00757         }
00758         return;
00759     }
00760 
00761     if(cplband[p->js_subband_start] > cplband[p->subbands-1]) return;
00762 
00763     length = cplband[p->subbands-1] - cplband[p->js_subband_start] + 1;
00764     for (i=0 ; i<length ; i++) {
00765        decouple_tab[cplband[p->js_subband_start] + i] = get_bits(&q->gb, p->js_vlc_bits);
00766     }
00767     return;
00768 }
00769 
00770 /*
00771  * function decouples a pair of signals from a single signal via multiplication.
00772  *
00773  * @param q                 pointer to the COOKContext
00774  * @param subband           index of the current subband
00775  * @param f1                multiplier for channel 1 extraction
00776  * @param f2                multiplier for channel 2 extraction
00777  * @param decode_buffer     input buffer
00778  * @param mlt_buffer1       pointer to left channel mlt coefficients
00779  * @param mlt_buffer2       pointer to right channel mlt coefficients
00780  */
00781 static void decouple_float (COOKContext *q,
00782                             COOKSubpacket *p,
00783                             int subband,
00784                             float f1, float f2,
00785                             float *decode_buffer,
00786                             float *mlt_buffer1, float *mlt_buffer2)
00787 {
00788     int j, tmp_idx;
00789     for (j=0 ; j<SUBBAND_SIZE ; j++) {
00790         tmp_idx = ((p->js_subband_start + subband)*SUBBAND_SIZE)+j;
00791         mlt_buffer1[SUBBAND_SIZE*subband + j] = f1 * decode_buffer[tmp_idx];
00792         mlt_buffer2[SUBBAND_SIZE*subband + j] = f2 * decode_buffer[tmp_idx];
00793     }
00794 }
00795 
00804 static void joint_decode(COOKContext *q, COOKSubpacket *p, float* mlt_buffer1,
00805                          float* mlt_buffer2) {
00806     int i,j;
00807     int decouple_tab[SUBBAND_SIZE];
00808     float *decode_buffer = q->decode_buffer_0;
00809     int idx, cpl_tmp;
00810     float f1,f2;
00811     const float* cplscale;
00812 
00813     memset(decouple_tab, 0, sizeof(decouple_tab));
00814     memset(decode_buffer, 0, sizeof(decode_buffer));
00815 
00816     /* Make sure the buffers are zeroed out. */
00817     memset(mlt_buffer1,0, 1024*sizeof(float));
00818     memset(mlt_buffer2,0, 1024*sizeof(float));
00819     decouple_info(q, p, decouple_tab);
00820     mono_decode(q, p, decode_buffer);
00821 
00822     /* The two channels are stored interleaved in decode_buffer. */
00823     for (i=0 ; i<p->js_subband_start ; i++) {
00824         for (j=0 ; j<SUBBAND_SIZE ; j++) {
00825             mlt_buffer1[i*20+j] = decode_buffer[i*40+j];
00826             mlt_buffer2[i*20+j] = decode_buffer[i*40+20+j];
00827         }
00828     }
00829 
00830     /* When we reach js_subband_start (the higher frequencies)
00831        the coefficients are stored in a coupling scheme. */
00832     idx = (1 << p->js_vlc_bits) - 1;
00833     for (i=p->js_subband_start ; i<p->subbands ; i++) {
00834         cpl_tmp = cplband[i];
00835         idx -=decouple_tab[cpl_tmp];
00836         cplscale = q->cplscales[p->js_vlc_bits-2];  //choose decoupler table
00837         f1 = cplscale[decouple_tab[cpl_tmp]];
00838         f2 = cplscale[idx-1];
00839         q->decouple (q, p, i, f1, f2, decode_buffer, mlt_buffer1, mlt_buffer2);
00840         idx = (1 << p->js_vlc_bits) - 1;
00841     }
00842 }
00843 
00853 static inline void
00854 decode_bytes_and_gain(COOKContext *q, COOKSubpacket *p, const uint8_t *inbuffer,
00855                       cook_gains *gains_ptr)
00856 {
00857     int offset;
00858 
00859     offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
00860                           p->bits_per_subpacket/8);
00861     init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
00862                   p->bits_per_subpacket);
00863     decode_gain_info(&q->gb, gains_ptr->now);
00864 
00865     /* Swap current and previous gains */
00866     FFSWAP(int *, gains_ptr->now, gains_ptr->previous);
00867 }
00868 
00876 static void
00877 saturate_output_float (COOKContext *q, int chan, int16_t *out)
00878 {
00879     int j;
00880     float *output = q->mono_mdct_output + q->samples_per_channel;
00881     /* Clip and convert floats to 16 bits.
00882      */
00883     for (j = 0; j < q->samples_per_channel; j++) {
00884         out[chan + q->nb_channels * j] =
00885           av_clip_int16(lrintf(output[j]));
00886     }
00887 }
00888 
00902 static inline void
00903 mlt_compensate_output(COOKContext *q, float *decode_buffer,
00904                       cook_gains *gains_ptr, float *previous_buffer,
00905                       int16_t *out, int chan)
00906 {
00907     imlt_gain(q, decode_buffer, gains_ptr, previous_buffer);
00908     q->saturate_output (q, chan, out);
00909 }
00910 
00911 
00920 static void decode_subpacket(COOKContext *q, COOKSubpacket* p, const uint8_t *inbuffer, int16_t *outbuffer) {
00921     int sub_packet_size = p->size;
00922     /* packet dump */
00923 //    for (i=0 ; i<sub_packet_size ; i++) {
00924 //        av_log(q->avctx, AV_LOG_ERROR, "%02x", inbuffer[i]);
00925 //    }
00926 //    av_log(q->avctx, AV_LOG_ERROR, "\n");
00927     memset(q->decode_buffer_1,0,sizeof(q->decode_buffer_1));
00928     decode_bytes_and_gain(q, p, inbuffer, &p->gains1);
00929 
00930     if (p->joint_stereo) {
00931         joint_decode(q, p, q->decode_buffer_1, q->decode_buffer_2);
00932     } else {
00933         mono_decode(q, p, q->decode_buffer_1);
00934 
00935         if (p->num_channels == 2) {
00936             decode_bytes_and_gain(q, p, inbuffer + sub_packet_size/2, &p->gains2);
00937             mono_decode(q, p, q->decode_buffer_2);
00938         }
00939     }
00940 
00941     mlt_compensate_output(q, q->decode_buffer_1, &p->gains1,
00942                           p->mono_previous_buffer1, outbuffer, p->ch_idx);
00943 
00944     if (p->num_channels == 2) {
00945         if (p->joint_stereo) {
00946             mlt_compensate_output(q, q->decode_buffer_2, &p->gains1,
00947                                   p->mono_previous_buffer2, outbuffer, p->ch_idx + 1);
00948          } else {
00949             mlt_compensate_output(q, q->decode_buffer_2, &p->gains2,
00950                                   p->mono_previous_buffer2, outbuffer, p->ch_idx + 1);
00951          }
00952      }
00953 
00954 }
00955 
00956 
00963 static int cook_decode_frame(AVCodecContext *avctx,
00964             void *data, int *data_size,
00965             AVPacket *avpkt) {
00966     const uint8_t *buf = avpkt->data;
00967     int buf_size = avpkt->size;
00968     COOKContext *q = avctx->priv_data;
00969     int i;
00970     int offset = 0;
00971     int chidx = 0;
00972 
00973     if (buf_size < avctx->block_align)
00974         return buf_size;
00975 
00976     /* estimate subpacket sizes */
00977     q->subpacket[0].size = avctx->block_align;
00978 
00979     for(i=1;i<q->num_subpackets;i++){
00980         q->subpacket[i].size = 2 * buf[avctx->block_align - q->num_subpackets + i];
00981         q->subpacket[0].size -= q->subpacket[i].size + 1;
00982         if (q->subpacket[0].size < 0) {
00983             av_log(avctx,AV_LOG_DEBUG,"frame subpacket size total > avctx->block_align!\n");
00984             return -1;
00985         }
00986     }
00987 
00988     /* decode supbackets */
00989     *data_size = 0;
00990     for(i=0;i<q->num_subpackets;i++){
00991         q->subpacket[i].bits_per_subpacket = (q->subpacket[i].size*8)>>q->subpacket[i].bits_per_subpdiv;
00992         q->subpacket[i].ch_idx = chidx;
00993         av_log(avctx,AV_LOG_DEBUG,"subpacket[%i] size %i js %i %i block_align %i\n",i,q->subpacket[i].size,q->subpacket[i].joint_stereo,offset,avctx->block_align);
00994         decode_subpacket(q, &q->subpacket[i], buf + offset, (int16_t*)data);
00995         offset += q->subpacket[i].size;
00996         chidx += q->subpacket[i].num_channels;
00997         av_log(avctx,AV_LOG_DEBUG,"subpacket[%i] %i %i\n",i,q->subpacket[i].size * 8,get_bits_count(&q->gb));
00998     }
00999     *data_size = sizeof(int16_t) * q->nb_channels * q->samples_per_channel;
01000 
01001     /* Discard the first two frames: no valid audio. */
01002     if (avctx->frame_number < 2) *data_size = 0;
01003 
01004     return avctx->block_align;
01005 }
01006 
01007 #ifdef DEBUG
01008 static void dump_cook_context(COOKContext *q)
01009 {
01010     //int i=0;
01011 #define PRINT(a,b) av_log(q->avctx,AV_LOG_ERROR," %s = %d\n", a, b);
01012     av_log(q->avctx,AV_LOG_ERROR,"COOKextradata\n");
01013     av_log(q->avctx,AV_LOG_ERROR,"cookversion=%x\n",q->subpacket[0].cookversion);
01014     if (q->subpacket[0].cookversion > STEREO) {
01015         PRINT("js_subband_start",q->subpacket[0].js_subband_start);
01016         PRINT("js_vlc_bits",q->subpacket[0].js_vlc_bits);
01017     }
01018     av_log(q->avctx,AV_LOG_ERROR,"COOKContext\n");
01019     PRINT("nb_channels",q->nb_channels);
01020     PRINT("bit_rate",q->bit_rate);
01021     PRINT("sample_rate",q->sample_rate);
01022     PRINT("samples_per_channel",q->subpacket[0].samples_per_channel);
01023     PRINT("samples_per_frame",q->subpacket[0].samples_per_frame);
01024     PRINT("subbands",q->subpacket[0].subbands);
01025     PRINT("js_subband_start",q->subpacket[0].js_subband_start);
01026     PRINT("log2_numvector_size",q->subpacket[0].log2_numvector_size);
01027     PRINT("numvector_size",q->subpacket[0].numvector_size);
01028     PRINT("total_subbands",q->subpacket[0].total_subbands);
01029 }
01030 #endif
01031 
01032 static av_cold int cook_count_channels(unsigned int mask){
01033     int i;
01034     int channels = 0;
01035     for(i = 0;i<32;i++){
01036         if(mask & (1<<i))
01037             ++channels;
01038     }
01039     return channels;
01040 }
01041 
01048 static av_cold int cook_decode_init(AVCodecContext *avctx)
01049 {
01050     COOKContext *q = avctx->priv_data;
01051     const uint8_t *edata_ptr = avctx->extradata;
01052     const uint8_t *edata_ptr_end = edata_ptr + avctx->extradata_size;
01053     int extradata_size = avctx->extradata_size;
01054     int s = 0;
01055     unsigned int channel_mask = 0;
01056     q->avctx = avctx;
01057 
01058     /* Take care of the codec specific extradata. */
01059     if (extradata_size <= 0) {
01060         av_log(avctx,AV_LOG_ERROR,"Necessary extradata missing!\n");
01061         return -1;
01062     }
01063     av_log(avctx,AV_LOG_DEBUG,"codecdata_length=%d\n",avctx->extradata_size);
01064 
01065     /* Take data from the AVCodecContext (RM container). */
01066     q->sample_rate = avctx->sample_rate;
01067     q->nb_channels = avctx->channels;
01068     q->bit_rate = avctx->bit_rate;
01069 
01070     /* Initialize RNG. */
01071     av_lfg_init(&q->random_state, 0);
01072 
01073     while(edata_ptr < edata_ptr_end){
01074         /* 8 for mono, 16 for stereo, ? for multichannel
01075            Swap to right endianness so we don't need to care later on. */
01076         if (extradata_size >= 8){
01077             q->subpacket[s].cookversion = bytestream_get_be32(&edata_ptr);
01078             q->subpacket[s].samples_per_frame =  bytestream_get_be16(&edata_ptr);
01079             q->subpacket[s].subbands = bytestream_get_be16(&edata_ptr);
01080             extradata_size -= 8;
01081         }
01082         if (avctx->extradata_size >= 8){
01083             bytestream_get_be32(&edata_ptr);    //Unknown unused
01084             q->subpacket[s].js_subband_start = bytestream_get_be16(&edata_ptr);
01085             q->subpacket[s].js_vlc_bits = bytestream_get_be16(&edata_ptr);
01086             extradata_size -= 8;
01087         }
01088 
01089         /* Initialize extradata related variables. */
01090         q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame / q->nb_channels;
01091         q->subpacket[s].bits_per_subpacket = avctx->block_align * 8;
01092 
01093         /* Initialize default data states. */
01094         q->subpacket[s].log2_numvector_size = 5;
01095         q->subpacket[s].total_subbands = q->subpacket[s].subbands;
01096         q->subpacket[s].num_channels = 1;
01097 
01098         /* Initialize version-dependent variables */
01099 
01100         av_log(avctx,AV_LOG_DEBUG,"subpacket[%i].cookversion=%x\n",s,q->subpacket[s].cookversion);
01101         q->subpacket[s].joint_stereo = 0;
01102         switch (q->subpacket[s].cookversion) {
01103             case MONO:
01104                 if (q->nb_channels != 1) {
01105                     av_log_ask_for_sample(avctx, "Container channels != 1.\n");
01106                     return -1;
01107                 }
01108                 av_log(avctx,AV_LOG_DEBUG,"MONO\n");
01109                 break;
01110             case STEREO:
01111                 if (q->nb_channels != 1) {
01112                     q->subpacket[s].bits_per_subpdiv = 1;
01113                     q->subpacket[s].num_channels = 2;
01114                 }
01115                 av_log(avctx,AV_LOG_DEBUG,"STEREO\n");
01116                 break;
01117             case JOINT_STEREO:
01118                 if (q->nb_channels != 2) {
01119                     av_log_ask_for_sample(avctx, "Container channels != 2.\n");
01120                     return -1;
01121                 }
01122                 av_log(avctx,AV_LOG_DEBUG,"JOINT_STEREO\n");
01123                 if (avctx->extradata_size >= 16){
01124                     q->subpacket[s].total_subbands = q->subpacket[s].subbands + q->subpacket[s].js_subband_start;
01125                     q->subpacket[s].joint_stereo = 1;
01126                     q->subpacket[s].num_channels = 2;
01127                 }
01128                 if (q->subpacket[s].samples_per_channel > 256) {
01129                     q->subpacket[s].log2_numvector_size  = 6;
01130                 }
01131                 if (q->subpacket[s].samples_per_channel > 512) {
01132                     q->subpacket[s].log2_numvector_size  = 7;
01133                 }
01134                 break;
01135             case MC_COOK:
01136                 av_log(avctx,AV_LOG_DEBUG,"MULTI_CHANNEL\n");
01137                 if(extradata_size >= 4)
01138                     channel_mask |= q->subpacket[s].channel_mask = bytestream_get_be32(&edata_ptr);
01139 
01140                 if(cook_count_channels(q->subpacket[s].channel_mask) > 1){
01141                     q->subpacket[s].total_subbands = q->subpacket[s].subbands + q->subpacket[s].js_subband_start;
01142                     q->subpacket[s].joint_stereo = 1;
01143                     q->subpacket[s].num_channels = 2;
01144                     q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame >> 1;
01145 
01146                     if (q->subpacket[s].samples_per_channel > 256) {
01147                         q->subpacket[s].log2_numvector_size  = 6;
01148                     }
01149                     if (q->subpacket[s].samples_per_channel > 512) {
01150                         q->subpacket[s].log2_numvector_size  = 7;
01151                     }
01152                 }else
01153                     q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame;
01154 
01155                 break;
01156             default:
01157                 av_log_ask_for_sample(avctx, "Unknown Cook version.\n");
01158                 return -1;
01159                 break;
01160         }
01161 
01162         if(s > 1 && q->subpacket[s].samples_per_channel != q->samples_per_channel) {
01163             av_log(avctx,AV_LOG_ERROR,"different number of samples per channel!\n");
01164             return -1;
01165         } else
01166             q->samples_per_channel = q->subpacket[0].samples_per_channel;
01167 
01168 
01169         /* Initialize variable relations */
01170         q->subpacket[s].numvector_size = (1 << q->subpacket[s].log2_numvector_size);
01171 
01172         /* Try to catch some obviously faulty streams, othervise it might be exploitable */
01173         if (q->subpacket[s].total_subbands > 53) {
01174             av_log_ask_for_sample(avctx, "total_subbands > 53\n");
01175             return -1;
01176         }
01177 
01178         if ((q->subpacket[s].js_vlc_bits > 6) || (q->subpacket[s].js_vlc_bits < 0)) {
01179             av_log(avctx,AV_LOG_ERROR,"js_vlc_bits = %d, only >= 0 and <= 6 allowed!\n",q->subpacket[s].js_vlc_bits);
01180             return -1;
01181         }
01182 
01183         if (q->subpacket[s].subbands > 50) {
01184             av_log_ask_for_sample(avctx, "subbands > 50\n");
01185             return -1;
01186         }
01187         q->subpacket[s].gains1.now      = q->subpacket[s].gain_1;
01188         q->subpacket[s].gains1.previous = q->subpacket[s].gain_2;
01189         q->subpacket[s].gains2.now      = q->subpacket[s].gain_3;
01190         q->subpacket[s].gains2.previous = q->subpacket[s].gain_4;
01191 
01192         q->num_subpackets++;
01193         s++;
01194         if (s > MAX_SUBPACKETS) {
01195             av_log_ask_for_sample(avctx, "Too many subpackets > 5\n");
01196             return -1;
01197         }
01198     }
01199     /* Generate tables */
01200     init_pow2table();
01201     init_gain_table(q);
01202     init_cplscales_table(q);
01203 
01204     if (init_cook_vlc_tables(q) != 0)
01205         return -1;
01206 
01207 
01208     if(avctx->block_align >= UINT_MAX/2)
01209         return -1;
01210 
01211     /* Pad the databuffer with:
01212        DECODE_BYTES_PAD1 or DECODE_BYTES_PAD2 for decode_bytes(),
01213        FF_INPUT_BUFFER_PADDING_SIZE, for the bitstreamreader. */
01214         q->decoded_bytes_buffer =
01215           av_mallocz(avctx->block_align
01216                      + DECODE_BYTES_PAD1(avctx->block_align)
01217                      + FF_INPUT_BUFFER_PADDING_SIZE);
01218     if (q->decoded_bytes_buffer == NULL)
01219         return -1;
01220 
01221     /* Initialize transform. */
01222     if ( init_cook_mlt(q) != 0 )
01223         return -1;
01224 
01225     /* Initialize COOK signal arithmetic handling */
01226     if (1) {
01227         q->scalar_dequant  = scalar_dequant_float;
01228         q->decouple        = decouple_float;
01229         q->imlt_window     = imlt_window_float;
01230         q->interpolate     = interpolate_float;
01231         q->saturate_output = saturate_output_float;
01232     }
01233 
01234     /* Try to catch some obviously faulty streams, othervise it might be exploitable */
01235     if ((q->samples_per_channel == 256) || (q->samples_per_channel == 512) || (q->samples_per_channel == 1024)) {
01236     } else {
01237         av_log_ask_for_sample(avctx,
01238                               "unknown amount of samples_per_channel = %d\n",
01239                               q->samples_per_channel);
01240         return -1;
01241     }
01242 
01243     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
01244     if (channel_mask)
01245         avctx->channel_layout = channel_mask;
01246     else
01247         avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
01248 
01249 #ifdef DEBUG
01250     dump_cook_context(q);
01251 #endif
01252     return 0;
01253 }
01254 
01255 
01256 AVCodec ff_cook_decoder =
01257 {
01258     .name = "cook",
01259     .type = AVMEDIA_TYPE_AUDIO,
01260     .id = CODEC_ID_COOK,
01261     .priv_data_size = sizeof(COOKContext),
01262     .init = cook_decode_init,
01263     .close = cook_decode_close,
01264     .decode = cook_decode_frame,
01265     .long_name = NULL_IF_CONFIG_SMALL("COOK"),
01266 };