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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 FFmpeg.
00007  *
00008  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 
00057 #include "cookdata.h"
00058 
00059 /* the different Cook versions */
00060 #define MONO            0x1000001
00061 #define STEREO          0x1000002
00062 #define JOINT_STEREO    0x1000003
00063 #define MC_COOK         0x2000000   //multichannel Cook, not supported
00064 
00065 #define SUBBAND_SIZE    20
00066 #define MAX_SUBPACKETS   5
00067 //#define COOKDEBUG
00068 
00069 typedef struct {
00070     int *now;
00071     int *previous;
00072 } cook_gains;
00073 
00074 typedef struct {
00075     int                 ch_idx;
00076     int                 size;
00077     int                 num_channels;
00078     int                 cookversion;
00079     int                 samples_per_frame;
00080     int                 subbands;
00081     int                 js_subband_start;
00082     int                 js_vlc_bits;
00083     int                 samples_per_channel;
00084     int                 log2_numvector_size;
00085     unsigned int        channel_mask;
00086     VLC                 ccpl;                 
00087     int                 joint_stereo;
00088     int                 bits_per_subpacket;
00089     int                 bits_per_subpdiv;
00090     int                 total_subbands;
00091     int                 numvector_size;       
00092 
00093     float               mono_previous_buffer1[1024];
00094     float               mono_previous_buffer2[1024];
00096     cook_gains          gains1;
00097     cook_gains          gains2;
00098     int                 gain_1[9];
00099     int                 gain_2[9];
00100     int                 gain_3[9];
00101     int                 gain_4[9];
00102 } COOKSubpacket;
00103 
00104 typedef struct cook {
00105     /*
00106      * The following 5 functions provide the lowlevel arithmetic on
00107      * the internal audio buffers.
00108      */
00109     void (* scalar_dequant)(struct cook *q, int index, int quant_index,
00110                             int* subband_coef_index, int* subband_coef_sign,
00111                             float* mlt_p);
00112 
00113     void (* decouple) (struct cook *q,
00114                        COOKSubpacket *p,
00115                        int subband,
00116                        float f1, float f2,
00117                        float *decode_buffer,
00118                        float *mlt_buffer1, float *mlt_buffer2);
00119 
00120     void (* imlt_window) (struct cook *q, float *buffer1,
00121                           cook_gains *gains_ptr, float *previous_buffer);
00122 
00123     void (* interpolate) (struct cook *q, float* buffer,
00124                           int gain_index, int gain_index_next);
00125 
00126     void (* saturate_output) (struct cook *q, int chan, int16_t *out);
00127 
00128     AVCodecContext*     avctx;
00129     GetBitContext       gb;
00130     /* stream data */
00131     int                 nb_channels;
00132     int                 bit_rate;
00133     int                 sample_rate;
00134     int                 num_vectors;
00135     int                 samples_per_channel;
00136     /* states */
00137     AVLFG               random_state;
00138 
00139     /* transform data */
00140     FFTContext          mdct_ctx;
00141     float*              mlt_window;
00142 
00143     /* VLC data */
00144     VLC                 envelope_quant_index[13];
00145     VLC                 sqvh[7];          //scalar quantization
00146 
00147     /* generatable tables and related variables */
00148     int                 gain_size_factor;
00149     float               gain_table[23];
00150 
00151     /* data buffers */
00152 
00153     uint8_t*            decoded_bytes_buffer;
00154     DECLARE_ALIGNED(16, float,mono_mdct_output)[2048];
00155     float               decode_buffer_1[1024];
00156     float               decode_buffer_2[1024];
00157     float               decode_buffer_0[1060]; /* static allocation for joint decode */
00158 
00159     const float         *cplscales[5];
00160     int                 num_subpackets;
00161     COOKSubpacket       subpacket[MAX_SUBPACKETS];
00162 } COOKContext;
00163 
00164 static float     pow2tab[127];
00165 static float rootpow2tab[127];
00166 
00167 /* debug functions */
00168 
00169 #ifdef COOKDEBUG
00170 static void dump_float_table(float* table, int size, int delimiter) {
00171     int i=0;
00172     av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
00173     for (i=0 ; i<size ; i++) {
00174         av_log(NULL, AV_LOG_ERROR, "%5.1f, ", table[i]);
00175         if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
00176     }
00177 }
00178 
00179 static void dump_int_table(int* table, int size, int delimiter) {
00180     int i=0;
00181     av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
00182     for (i=0 ; i<size ; i++) {
00183         av_log(NULL, AV_LOG_ERROR, "%d, ", table[i]);
00184         if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
00185     }
00186 }
00187 
00188 static void dump_short_table(short* table, int size, int delimiter) {
00189     int i=0;
00190     av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
00191     for (i=0 ; i<size ; i++) {
00192         av_log(NULL, AV_LOG_ERROR, "%d, ", table[i]);
00193         if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
00194     }
00195 }
00196 
00197 #endif
00198 
00199 /*************** init functions ***************/
00200 
00201 /* table generator */
00202 static av_cold void init_pow2table(void){
00203     int i;
00204     for (i=-63 ; i<64 ; i++){
00205             pow2tab[63+i]=     pow(2, i);
00206         rootpow2tab[63+i]=sqrt(pow(2, i));
00207     }
00208 }
00209 
00210 /* table generator */
00211 static av_cold void init_gain_table(COOKContext *q) {
00212     int i;
00213     q->gain_size_factor = q->samples_per_channel/8;
00214     for (i=0 ; i<23 ; i++) {
00215         q->gain_table[i] = pow(pow2tab[i+52] ,
00216                                (1.0/(double)q->gain_size_factor));
00217     }
00218 }
00219 
00220 
00221 static av_cold int init_cook_vlc_tables(COOKContext *q) {
00222     int i, result;
00223 
00224     result = 0;
00225     for (i=0 ; i<13 ; i++) {
00226         result |= init_vlc (&q->envelope_quant_index[i], 9, 24,
00227             envelope_quant_index_huffbits[i], 1, 1,
00228             envelope_quant_index_huffcodes[i], 2, 2, 0);
00229     }
00230     av_log(q->avctx,AV_LOG_DEBUG,"sqvh VLC init\n");
00231     for (i=0 ; i<7 ; i++) {
00232         result |= init_vlc (&q->sqvh[i], vhvlcsize_tab[i], vhsize_tab[i],
00233             cvh_huffbits[i], 1, 1,
00234             cvh_huffcodes[i], 2, 2, 0);
00235     }
00236 
00237     for(i=0;i<q->num_subpackets;i++){
00238         if (q->subpacket[i].joint_stereo==1){
00239             result |= init_vlc (&q->subpacket[i].ccpl, 6, (1<<q->subpacket[i].js_vlc_bits)-1,
00240                 ccpl_huffbits[q->subpacket[i].js_vlc_bits-2], 1, 1,
00241                 ccpl_huffcodes[q->subpacket[i].js_vlc_bits-2], 2, 2, 0);
00242             av_log(q->avctx,AV_LOG_DEBUG,"subpacket %i Joint-stereo VLC used.\n",i);
00243         }
00244     }
00245 
00246     av_log(q->avctx,AV_LOG_DEBUG,"VLC tables initialized.\n");
00247     return result;
00248 }
00249 
00250 static av_cold int init_cook_mlt(COOKContext *q) {
00251     int j;
00252     int mlt_size = q->samples_per_channel;
00253 
00254     if ((q->mlt_window = av_malloc(sizeof(float)*mlt_size)) == 0)
00255       return -1;
00256 
00257     /* Initialize the MLT window: simple sine window. */
00258     ff_sine_window_init(q->mlt_window, mlt_size);
00259     for(j=0 ; j<mlt_size ; j++)
00260         q->mlt_window[j] *= sqrt(2.0 / q->samples_per_channel);
00261 
00262     /* Initialize the MDCT. */
00263     if (ff_mdct_init(&q->mdct_ctx, av_log2(mlt_size)+1, 1, 1.0)) {
00264       av_free(q->mlt_window);
00265       return -1;
00266     }
00267     av_log(q->avctx,AV_LOG_DEBUG,"MDCT initialized, order = %d.\n",
00268            av_log2(mlt_size)+1);
00269 
00270     return 0;
00271 }
00272 
00273 static const float *maybe_reformat_buffer32 (COOKContext *q, const float *ptr, int n)
00274 {
00275     if (1)
00276         return ptr;
00277 }
00278 
00279 static av_cold void init_cplscales_table (COOKContext *q) {
00280     int i;
00281     for (i=0;i<5;i++)
00282         q->cplscales[i] = maybe_reformat_buffer32 (q, cplscales[i], (1<<(i+2))-1);
00283 }
00284 
00285 /*************** init functions end ***********/
00286 
00307 #define DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
00308 #define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
00309 
00310 static inline int decode_bytes(const uint8_t* inbuffer, uint8_t* out, int bytes){
00311     int i, off;
00312     uint32_t c;
00313     const uint32_t* buf;
00314     uint32_t* obuf = (uint32_t*) out;
00315     /* FIXME: 64 bit platforms would be able to do 64 bits at a time.
00316      * I'm too lazy though, should be something like
00317      * for(i=0 ; i<bitamount/64 ; i++)
00318      *     (int64_t)out[i] = 0x37c511f237c511f2^be2me_64(int64_t)in[i]);
00319      * Buffer alignment needs to be checked. */
00320 
00321     off = (intptr_t)inbuffer & 3;
00322     buf = (const uint32_t*) (inbuffer - off);
00323     c = be2me_32((0x37c511f2 >> (off*8)) | (0x37c511f2 << (32-(off*8))));
00324     bytes += 3 + off;
00325     for (i = 0; i < bytes/4; i++)
00326         obuf[i] = c ^ buf[i];
00327 
00328     return off;
00329 }
00330 
00335 static av_cold int cook_decode_close(AVCodecContext *avctx)
00336 {
00337     int i;
00338     COOKContext *q = avctx->priv_data;
00339     av_log(avctx,AV_LOG_DEBUG, "Deallocating memory.\n");
00340 
00341     /* Free allocated memory buffers. */
00342     av_free(q->mlt_window);
00343     av_free(q->decoded_bytes_buffer);
00344 
00345     /* Free the transform. */
00346     ff_mdct_end(&q->mdct_ctx);
00347 
00348     /* Free the VLC tables. */
00349     for (i=0 ; i<13 ; i++) {
00350         free_vlc(&q->envelope_quant_index[i]);
00351     }
00352     for (i=0 ; i<7 ; i++) {
00353         free_vlc(&q->sqvh[i]);
00354     }
00355     for (i=0 ; i<q->num_subpackets ; i++) {
00356         free_vlc(&q->subpacket[i].ccpl);
00357     }
00358 
00359     av_log(avctx,AV_LOG_DEBUG,"Memory deallocated.\n");
00360 
00361     return 0;
00362 }
00363 
00371 static void decode_gain_info(GetBitContext *gb, int *gaininfo)
00372 {
00373     int i, n;
00374 
00375     while (get_bits1(gb)) {}
00376     n = get_bits_count(gb) - 1;     //amount of elements*2 to update
00377 
00378     i = 0;
00379     while (n--) {
00380         int index = get_bits(gb, 3);
00381         int gain = get_bits1(gb) ? get_bits(gb, 4) - 7 : -1;
00382 
00383         while (i <= index) gaininfo[i++] = gain;
00384     }
00385     while (i <= 8) gaininfo[i++] = 0;
00386 }
00387 
00395 static void decode_envelope(COOKContext *q, COOKSubpacket *p, int* quant_index_table) {
00396     int i,j, vlc_index;
00397 
00398     quant_index_table[0]= get_bits(&q->gb,6) - 6;       //This is used later in categorize
00399 
00400     for (i=1 ; i < p->total_subbands ; i++){
00401         vlc_index=i;
00402         if (i >= p->js_subband_start * 2) {
00403             vlc_index-=p->js_subband_start;
00404         } else {
00405             vlc_index/=2;
00406             if(vlc_index < 1) vlc_index = 1;
00407         }
00408         if (vlc_index>13) vlc_index = 13;           //the VLC tables >13 are identical to No. 13
00409 
00410         j = get_vlc2(&q->gb, q->envelope_quant_index[vlc_index-1].table,
00411                      q->envelope_quant_index[vlc_index-1].bits,2);
00412         quant_index_table[i] = quant_index_table[i-1] + j - 12;    //differential encoding
00413     }
00414 }
00415 
00425 static void categorize(COOKContext *q, COOKSubpacket *p, int* quant_index_table,
00426                        int* category, int* category_index){
00427     int exp_idx, bias, tmpbias1, tmpbias2, bits_left, num_bits, index, v, i, j;
00428     int exp_index2[102];
00429     int exp_index1[102];
00430 
00431     int tmp_categorize_array[128*2];
00432     int tmp_categorize_array1_idx=p->numvector_size;
00433     int tmp_categorize_array2_idx=p->numvector_size;
00434 
00435     bits_left =  p->bits_per_subpacket - get_bits_count(&q->gb);
00436 
00437     if(bits_left > q->samples_per_channel) {
00438         bits_left = q->samples_per_channel +
00439                     ((bits_left - q->samples_per_channel)*5)/8;
00440         //av_log(q->avctx, AV_LOG_ERROR, "bits_left = %d\n",bits_left);
00441     }
00442 
00443     memset(&exp_index1,0,102*sizeof(int));
00444     memset(&exp_index2,0,102*sizeof(int));
00445     memset(&tmp_categorize_array,0,128*2*sizeof(int));
00446 
00447     bias=-32;
00448 
00449     /* Estimate bias. */
00450     for (i=32 ; i>0 ; i=i/2){
00451         num_bits = 0;
00452         index = 0;
00453         for (j=p->total_subbands ; j>0 ; j--){
00454             exp_idx = av_clip((i - quant_index_table[index] + bias) / 2, 0, 7);
00455             index++;
00456             num_bits+=expbits_tab[exp_idx];
00457         }
00458         if(num_bits >= bits_left - 32){
00459             bias+=i;
00460         }
00461     }
00462 
00463     /* Calculate total number of bits. */
00464     num_bits=0;
00465     for (i=0 ; i<p->total_subbands ; i++) {
00466         exp_idx = av_clip((bias - quant_index_table[i]) / 2, 0, 7);
00467         num_bits += expbits_tab[exp_idx];
00468         exp_index1[i] = exp_idx;
00469         exp_index2[i] = exp_idx;
00470     }
00471     tmpbias1 = tmpbias2 = num_bits;
00472 
00473     for (j = 1 ; j < p->numvector_size ; j++) {
00474         if (tmpbias1 + tmpbias2 > 2*bits_left) {  /* ---> */
00475             int max = -999999;
00476             index=-1;
00477             for (i=0 ; i<p->total_subbands ; i++){
00478                 if (exp_index1[i] < 7) {
00479                     v = (-2*exp_index1[i]) - quant_index_table[i] + bias;
00480                     if ( v >= max) {
00481                         max = v;
00482                         index = i;
00483                     }
00484                 }
00485             }
00486             if(index==-1)break;
00487             tmp_categorize_array[tmp_categorize_array1_idx++] = index;
00488             tmpbias1 -= expbits_tab[exp_index1[index]] -
00489                         expbits_tab[exp_index1[index]+1];
00490             ++exp_index1[index];
00491         } else {  /* <--- */
00492             int min = 999999;
00493             index=-1;
00494             for (i=0 ; i<p->total_subbands ; i++){
00495                 if(exp_index2[i] > 0){
00496                     v = (-2*exp_index2[i])-quant_index_table[i]+bias;
00497                     if ( v < min) {
00498                         min = v;
00499                         index = i;
00500                     }
00501                 }
00502             }
00503             if(index == -1)break;
00504             tmp_categorize_array[--tmp_categorize_array2_idx] = index;
00505             tmpbias2 -= expbits_tab[exp_index2[index]] -
00506                         expbits_tab[exp_index2[index]-1];
00507             --exp_index2[index];
00508         }
00509     }
00510 
00511     for(i=0 ; i<p->total_subbands ; i++)
00512         category[i] = exp_index2[i];
00513 
00514     for(i=0 ; i<p->numvector_size-1 ; i++)
00515         category_index[i] = tmp_categorize_array[tmp_categorize_array2_idx++];
00516 
00517 }
00518 
00519 
00528 static inline void expand_category(COOKContext *q, int* category,
00529                                    int* category_index){
00530     int i;
00531     for(i=0 ; i<q->num_vectors ; i++){
00532         ++category[category_index[i]];
00533     }
00534 }
00535 
00547 static void scalar_dequant_float(COOKContext *q, int index, int quant_index,
00548                            int* subband_coef_index, int* subband_coef_sign,
00549                            float* mlt_p){
00550     int i;
00551     float f1;
00552 
00553     for(i=0 ; i<SUBBAND_SIZE ; i++) {
00554         if (subband_coef_index[i]) {
00555             f1 = quant_centroid_tab[index][subband_coef_index[i]];
00556             if (subband_coef_sign[i]) f1 = -f1;
00557         } else {
00558             /* noise coding if subband_coef_index[i] == 0 */
00559             f1 = dither_tab[index];
00560             if (av_lfg_get(&q->random_state) < 0x80000000) f1 = -f1;
00561         }
00562         mlt_p[i] = f1 * rootpow2tab[quant_index+63];
00563     }
00564 }
00574 static int unpack_SQVH(COOKContext *q, COOKSubpacket *p, int category, int* subband_coef_index,
00575                        int* subband_coef_sign) {
00576     int i,j;
00577     int vlc, vd ,tmp, result;
00578 
00579     vd = vd_tab[category];
00580     result = 0;
00581     for(i=0 ; i<vpr_tab[category] ; i++){
00582         vlc = get_vlc2(&q->gb, q->sqvh[category].table, q->sqvh[category].bits, 3);
00583         if (p->bits_per_subpacket < get_bits_count(&q->gb)){
00584             vlc = 0;
00585             result = 1;
00586         }
00587         for(j=vd-1 ; j>=0 ; j--){
00588             tmp = (vlc * invradix_tab[category])/0x100000;
00589             subband_coef_index[vd*i+j] = vlc - tmp * (kmax_tab[category]+1);
00590             vlc = tmp;
00591         }
00592         for(j=0 ; j<vd ; j++){
00593             if (subband_coef_index[i*vd + j]) {
00594                 if(get_bits_count(&q->gb) < p->bits_per_subpacket){
00595                     subband_coef_sign[i*vd+j] = get_bits1(&q->gb);
00596                 } else {
00597                     result=1;
00598                     subband_coef_sign[i*vd+j]=0;
00599                 }
00600             } else {
00601                 subband_coef_sign[i*vd+j]=0;
00602             }
00603         }
00604     }
00605     return result;
00606 }
00607 
00608 
00619 static void decode_vectors(COOKContext* q, COOKSubpacket* p, int* category,
00620                            int *quant_index_table, float* mlt_buffer){
00621     /* A zero in this table means that the subband coefficient is
00622        random noise coded. */
00623     int subband_coef_index[SUBBAND_SIZE];
00624     /* A zero in this table means that the subband coefficient is a
00625        positive multiplicator. */
00626     int subband_coef_sign[SUBBAND_SIZE];
00627     int band, j;
00628     int index=0;
00629 
00630     for(band=0 ; band<p->total_subbands ; band++){
00631         index = category[band];
00632         if(category[band] < 7){
00633             if(unpack_SQVH(q, p, category[band], subband_coef_index, subband_coef_sign)){
00634                 index=7;
00635                 for(j=0 ; j<p->total_subbands ; j++) category[band+j]=7;
00636             }
00637         }
00638         if(index>=7) {
00639             memset(subband_coef_index, 0, sizeof(subband_coef_index));
00640             memset(subband_coef_sign, 0, sizeof(subband_coef_sign));
00641         }
00642         q->scalar_dequant(q, index, quant_index_table[band],
00643                           subband_coef_index, subband_coef_sign,
00644                           &mlt_buffer[band * SUBBAND_SIZE]);
00645     }
00646 
00647     if(p->total_subbands*SUBBAND_SIZE >= q->samples_per_channel){
00648         return;
00649     } /* FIXME: should this be removed, or moved into loop above? */
00650 }
00651 
00652 
00660 static void mono_decode(COOKContext *q, COOKSubpacket *p, float* mlt_buffer) {
00661 
00662     int category_index[128];
00663     int quant_index_table[102];
00664     int category[128];
00665 
00666     memset(&category, 0, 128*sizeof(int));
00667     memset(&category_index, 0, 128*sizeof(int));
00668 
00669     decode_envelope(q, p, quant_index_table);
00670     q->num_vectors = get_bits(&q->gb,p->log2_numvector_size);
00671     categorize(q, p, quant_index_table, category, category_index);
00672     expand_category(q, category, category_index);
00673     decode_vectors(q, p, category, quant_index_table, mlt_buffer);
00674 }
00675 
00676 
00686 static void interpolate_float(COOKContext *q, float* buffer,
00687                         int gain_index, int gain_index_next){
00688     int i;
00689     float fc1, fc2;
00690     fc1 = pow2tab[gain_index+63];
00691 
00692     if(gain_index == gain_index_next){              //static gain
00693         for(i=0 ; i<q->gain_size_factor ; i++){
00694             buffer[i]*=fc1;
00695         }
00696         return;
00697     } else {                                        //smooth gain
00698         fc2 = q->gain_table[11 + (gain_index_next-gain_index)];
00699         for(i=0 ; i<q->gain_size_factor ; i++){
00700             buffer[i]*=fc1;
00701             fc1*=fc2;
00702         }
00703         return;
00704     }
00705 }
00706 
00716 static void imlt_window_float (COOKContext *q, float *buffer1,
00717                                cook_gains *gains_ptr, float *previous_buffer)
00718 {
00719     const float fc = pow2tab[gains_ptr->previous[0] + 63];
00720     int i;
00721     /* The weird thing here, is that the two halves of the time domain
00722      * buffer are swapped. Also, the newest data, that we save away for
00723      * next frame, has the wrong sign. Hence the subtraction below.
00724      * Almost sounds like a complex conjugate/reverse data/FFT effect.
00725      */
00726 
00727     /* Apply window and overlap */
00728     for(i = 0; i < q->samples_per_channel; i++){
00729         buffer1[i] = buffer1[i] * fc * q->mlt_window[i] -
00730           previous_buffer[i] * q->mlt_window[q->samples_per_channel - 1 - i];
00731     }
00732 }
00733 
00746 static void imlt_gain(COOKContext *q, float *inbuffer,
00747                       cook_gains *gains_ptr, float* previous_buffer)
00748 {
00749     float *buffer0 = q->mono_mdct_output;
00750     float *buffer1 = q->mono_mdct_output + q->samples_per_channel;
00751     int i;
00752 
00753     /* Inverse modified discrete cosine transform */
00754     ff_imdct_calc(&q->mdct_ctx, q->mono_mdct_output, inbuffer);
00755 
00756     q->imlt_window (q, buffer1, gains_ptr, previous_buffer);
00757 
00758     /* Apply gain profile */
00759     for (i = 0; i < 8; i++) {
00760         if (gains_ptr->now[i] || gains_ptr->now[i + 1])
00761             q->interpolate(q, &buffer1[q->gain_size_factor * i],
00762                            gains_ptr->now[i], gains_ptr->now[i + 1]);
00763     }
00764 
00765     /* Save away the current to be previous block. */
00766     memcpy(previous_buffer, buffer0, sizeof(float)*q->samples_per_channel);
00767 }
00768 
00769 
00778 static void decouple_info(COOKContext *q, COOKSubpacket *p, int* decouple_tab){
00779     int length, i;
00780 
00781     if(get_bits1(&q->gb)) {
00782         if(cplband[p->js_subband_start] > cplband[p->subbands-1]) return;
00783 
00784         length = cplband[p->subbands-1] - cplband[p->js_subband_start] + 1;
00785         for (i=0 ; i<length ; i++) {
00786             decouple_tab[cplband[p->js_subband_start] + i] = get_vlc2(&q->gb, p->ccpl.table, p->ccpl.bits, 2);
00787         }
00788         return;
00789     }
00790 
00791     if(cplband[p->js_subband_start] > cplband[p->subbands-1]) return;
00792 
00793     length = cplband[p->subbands-1] - cplband[p->js_subband_start] + 1;
00794     for (i=0 ; i<length ; i++) {
00795        decouple_tab[cplband[p->js_subband_start] + i] = get_bits(&q->gb, p->js_vlc_bits);
00796     }
00797     return;
00798 }
00799 
00800 /*
00801  * function decouples a pair of signals from a single signal via multiplication.
00802  *
00803  * @param q                 pointer to the COOKContext
00804  * @param subband           index of the current subband
00805  * @param f1                multiplier for channel 1 extraction
00806  * @param f2                multiplier for channel 2 extraction
00807  * @param decode_buffer     input buffer
00808  * @param mlt_buffer1       pointer to left channel mlt coefficients
00809  * @param mlt_buffer2       pointer to right channel mlt coefficients
00810  */
00811 static void decouple_float (COOKContext *q,
00812                             COOKSubpacket *p,
00813                             int subband,
00814                             float f1, float f2,
00815                             float *decode_buffer,
00816                             float *mlt_buffer1, float *mlt_buffer2)
00817 {
00818     int j, tmp_idx;
00819     for (j=0 ; j<SUBBAND_SIZE ; j++) {
00820         tmp_idx = ((p->js_subband_start + subband)*SUBBAND_SIZE)+j;
00821         mlt_buffer1[SUBBAND_SIZE*subband + j] = f1 * decode_buffer[tmp_idx];
00822         mlt_buffer2[SUBBAND_SIZE*subband + j] = f2 * decode_buffer[tmp_idx];
00823     }
00824 }
00825 
00834 static void joint_decode(COOKContext *q, COOKSubpacket *p, float* mlt_buffer1,
00835                          float* mlt_buffer2) {
00836     int i,j;
00837     int decouple_tab[SUBBAND_SIZE];
00838     float *decode_buffer = q->decode_buffer_0;
00839     int idx, cpl_tmp;
00840     float f1,f2;
00841     const float* cplscale;
00842 
00843     memset(decouple_tab, 0, sizeof(decouple_tab));
00844     memset(decode_buffer, 0, sizeof(decode_buffer));
00845 
00846     /* Make sure the buffers are zeroed out. */
00847     memset(mlt_buffer1,0, 1024*sizeof(float));
00848     memset(mlt_buffer2,0, 1024*sizeof(float));
00849     decouple_info(q, p, decouple_tab);
00850     mono_decode(q, p, decode_buffer);
00851 
00852     /* The two channels are stored interleaved in decode_buffer. */
00853     for (i=0 ; i<p->js_subband_start ; i++) {
00854         for (j=0 ; j<SUBBAND_SIZE ; j++) {
00855             mlt_buffer1[i*20+j] = decode_buffer[i*40+j];
00856             mlt_buffer2[i*20+j] = decode_buffer[i*40+20+j];
00857         }
00858     }
00859 
00860     /* When we reach js_subband_start (the higher frequencies)
00861        the coefficients are stored in a coupling scheme. */
00862     idx = (1 << p->js_vlc_bits) - 1;
00863     for (i=p->js_subband_start ; i<p->subbands ; i++) {
00864         cpl_tmp = cplband[i];
00865         idx -=decouple_tab[cpl_tmp];
00866         cplscale = q->cplscales[p->js_vlc_bits-2];  //choose decoupler table
00867         f1 = cplscale[decouple_tab[cpl_tmp]];
00868         f2 = cplscale[idx-1];
00869         q->decouple (q, p, i, f1, f2, decode_buffer, mlt_buffer1, mlt_buffer2);
00870         idx = (1 << p->js_vlc_bits) - 1;
00871     }
00872 }
00873 
00883 static inline void
00884 decode_bytes_and_gain(COOKContext *q, COOKSubpacket *p, const uint8_t *inbuffer,
00885                       cook_gains *gains_ptr)
00886 {
00887     int offset;
00888 
00889     offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
00890                           p->bits_per_subpacket/8);
00891     init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
00892                   p->bits_per_subpacket);
00893     decode_gain_info(&q->gb, gains_ptr->now);
00894 
00895     /* Swap current and previous gains */
00896     FFSWAP(int *, gains_ptr->now, gains_ptr->previous);
00897 }
00898 
00906 static void
00907 saturate_output_float (COOKContext *q, int chan, int16_t *out)
00908 {
00909     int j;
00910     float *output = q->mono_mdct_output + q->samples_per_channel;
00911     /* Clip and convert floats to 16 bits.
00912      */
00913     for (j = 0; j < q->samples_per_channel; j++) {
00914         out[chan + q->nb_channels * j] =
00915           av_clip_int16(lrintf(output[j]));
00916     }
00917 }
00918 
00932 static inline void
00933 mlt_compensate_output(COOKContext *q, float *decode_buffer,
00934                       cook_gains *gains, float *previous_buffer,
00935                       int16_t *out, int chan)
00936 {
00937     imlt_gain(q, decode_buffer, gains, previous_buffer);
00938     q->saturate_output (q, chan, out);
00939 }
00940 
00941 
00953 static void decode_subpacket(COOKContext *q, COOKSubpacket* p, const uint8_t *inbuffer, int16_t *outbuffer) {
00954     int sub_packet_size = p->size;
00955     /* packet dump */
00956 //    for (i=0 ; i<sub_packet_size ; i++) {
00957 //        av_log(q->avctx, AV_LOG_ERROR, "%02x", inbuffer[i]);
00958 //    }
00959 //    av_log(q->avctx, AV_LOG_ERROR, "\n");
00960     memset(q->decode_buffer_1,0,sizeof(q->decode_buffer_1));
00961     decode_bytes_and_gain(q, p, inbuffer, &p->gains1);
00962 
00963     if (p->joint_stereo) {
00964         joint_decode(q, p, q->decode_buffer_1, q->decode_buffer_2);
00965     } else {
00966         mono_decode(q, p, q->decode_buffer_1);
00967 
00968         if (p->num_channels == 2) {
00969             decode_bytes_and_gain(q, p, inbuffer + sub_packet_size/2, &p->gains2);
00970             mono_decode(q, p, q->decode_buffer_2);
00971         }
00972     }
00973 
00974     mlt_compensate_output(q, q->decode_buffer_1, &p->gains1,
00975                           p->mono_previous_buffer1, outbuffer, p->ch_idx);
00976 
00977     if (p->num_channels == 2) {
00978         if (p->joint_stereo) {
00979             mlt_compensate_output(q, q->decode_buffer_2, &p->gains1,
00980                                   p->mono_previous_buffer2, outbuffer, p->ch_idx + 1);
00981          } else {
00982             mlt_compensate_output(q, q->decode_buffer_2, &p->gains2,
00983                                   p->mono_previous_buffer2, outbuffer, p->ch_idx + 1);
00984          }
00985      }
00986 
00987 }
00988 
00989 
00996 static int cook_decode_frame(AVCodecContext *avctx,
00997             void *data, int *data_size,
00998             AVPacket *avpkt) {
00999     const uint8_t *buf = avpkt->data;
01000     int buf_size = avpkt->size;
01001     COOKContext *q = avctx->priv_data;
01002     int i;
01003     int offset = 0;
01004     int chidx = 0;
01005 
01006     if (buf_size < avctx->block_align)
01007         return buf_size;
01008 
01009     /* estimate subpacket sizes */
01010     q->subpacket[0].size = avctx->block_align;
01011 
01012     for(i=1;i<q->num_subpackets;i++){
01013         q->subpacket[i].size = 2 * buf[avctx->block_align - q->num_subpackets + i];
01014         q->subpacket[0].size -= q->subpacket[i].size + 1;
01015         if (q->subpacket[0].size < 0) {
01016             av_log(avctx,AV_LOG_DEBUG,"frame subpacket size total > avctx->block_align!\n");
01017             return -1;
01018         }
01019     }
01020 
01021     /* decode supbackets */
01022     *data_size = 0;
01023     for(i=0;i<q->num_subpackets;i++){
01024         q->subpacket[i].bits_per_subpacket = (q->subpacket[i].size*8)>>q->subpacket[i].bits_per_subpdiv;
01025         q->subpacket[i].ch_idx = chidx;
01026         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);
01027         decode_subpacket(q, &q->subpacket[i], buf + offset, (int16_t*)data);
01028         offset += q->subpacket[i].size;
01029         chidx += q->subpacket[i].num_channels;
01030         av_log(avctx,AV_LOG_DEBUG,"subpacket[%i] %i %i\n",i,q->subpacket[i].size * 8,get_bits_count(&q->gb));
01031     }
01032     *data_size = sizeof(int16_t) * q->nb_channels * q->samples_per_channel;
01033 
01034     /* Discard the first two frames: no valid audio. */
01035     if (avctx->frame_number < 2) *data_size = 0;
01036 
01037     return avctx->block_align;
01038 }
01039 
01040 #ifdef COOKDEBUG
01041 static void dump_cook_context(COOKContext *q)
01042 {
01043     //int i=0;
01044 #define PRINT(a,b) av_log(q->avctx,AV_LOG_ERROR," %s = %d\n", a, b);
01045     av_log(q->avctx,AV_LOG_ERROR,"COOKextradata\n");
01046     av_log(q->avctx,AV_LOG_ERROR,"cookversion=%x\n",q->subpacket[0].cookversion);
01047     if (q->subpacket[0].cookversion > STEREO) {
01048         PRINT("js_subband_start",q->subpacket[0].js_subband_start);
01049         PRINT("js_vlc_bits",q->subpacket[0].js_vlc_bits);
01050     }
01051     av_log(q->avctx,AV_LOG_ERROR,"COOKContext\n");
01052     PRINT("nb_channels",q->nb_channels);
01053     PRINT("bit_rate",q->bit_rate);
01054     PRINT("sample_rate",q->sample_rate);
01055     PRINT("samples_per_channel",q->subpacket[0].samples_per_channel);
01056     PRINT("samples_per_frame",q->subpacket[0].samples_per_frame);
01057     PRINT("subbands",q->subpacket[0].subbands);
01058     PRINT("random_state",q->random_state);
01059     PRINT("js_subband_start",q->subpacket[0].js_subband_start);
01060     PRINT("log2_numvector_size",q->subpacket[0].log2_numvector_size);
01061     PRINT("numvector_size",q->subpacket[0].numvector_size);
01062     PRINT("total_subbands",q->subpacket[0].total_subbands);
01063 }
01064 #endif
01065 
01066 static av_cold int cook_count_channels(unsigned int mask){
01067     int i;
01068     int channels = 0;
01069     for(i = 0;i<32;i++){
01070         if(mask & (1<<i))
01071             ++channels;
01072     }
01073     return channels;
01074 }
01075 
01082 static av_cold int cook_decode_init(AVCodecContext *avctx)
01083 {
01084     COOKContext *q = avctx->priv_data;
01085     const uint8_t *edata_ptr = avctx->extradata;
01086     const uint8_t *edata_ptr_end = edata_ptr + avctx->extradata_size;
01087     int extradata_size = avctx->extradata_size;
01088     int s = 0;
01089     unsigned int channel_mask = 0;
01090     q->avctx = avctx;
01091 
01092     /* Take care of the codec specific extradata. */
01093     if (extradata_size <= 0) {
01094         av_log(avctx,AV_LOG_ERROR,"Necessary extradata missing!\n");
01095         return -1;
01096     }
01097     av_log(avctx,AV_LOG_DEBUG,"codecdata_length=%d\n",avctx->extradata_size);
01098 
01099     /* Take data from the AVCodecContext (RM container). */
01100     q->sample_rate = avctx->sample_rate;
01101     q->nb_channels = avctx->channels;
01102     q->bit_rate = avctx->bit_rate;
01103 
01104     /* Initialize RNG. */
01105     av_lfg_init(&q->random_state, 0);
01106 
01107     while(edata_ptr < edata_ptr_end){
01108         /* 8 for mono, 16 for stereo, ? for multichannel
01109            Swap to right endianness so we don't need to care later on. */
01110         if (extradata_size >= 8){
01111             q->subpacket[s].cookversion = bytestream_get_be32(&edata_ptr);
01112             q->subpacket[s].samples_per_frame =  bytestream_get_be16(&edata_ptr);
01113             q->subpacket[s].subbands = bytestream_get_be16(&edata_ptr);
01114             extradata_size -= 8;
01115         }
01116         if (avctx->extradata_size >= 8){
01117             bytestream_get_be32(&edata_ptr);    //Unknown unused
01118             q->subpacket[s].js_subband_start = bytestream_get_be16(&edata_ptr);
01119             q->subpacket[s].js_vlc_bits = bytestream_get_be16(&edata_ptr);
01120             extradata_size -= 8;
01121         }
01122 
01123         /* Initialize extradata related variables. */
01124         q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame / q->nb_channels;
01125         q->subpacket[s].bits_per_subpacket = avctx->block_align * 8;
01126 
01127         /* Initialize default data states. */
01128         q->subpacket[s].log2_numvector_size = 5;
01129         q->subpacket[s].total_subbands = q->subpacket[s].subbands;
01130         q->subpacket[s].num_channels = 1;
01131 
01132         /* Initialize version-dependent variables */
01133 
01134         av_log(avctx,AV_LOG_DEBUG,"subpacket[%i].cookversion=%x\n",s,q->subpacket[s].cookversion);
01135         q->subpacket[s].joint_stereo = 0;
01136         switch (q->subpacket[s].cookversion) {
01137             case MONO:
01138                 if (q->nb_channels != 1) {
01139                     av_log(avctx,AV_LOG_ERROR,"Container channels != 1, report sample!\n");
01140                     return -1;
01141                 }
01142                 av_log(avctx,AV_LOG_DEBUG,"MONO\n");
01143                 break;
01144             case STEREO:
01145                 if (q->nb_channels != 1) {
01146                     q->subpacket[s].bits_per_subpdiv = 1;
01147                     q->subpacket[s].num_channels = 2;
01148                 }
01149                 av_log(avctx,AV_LOG_DEBUG,"STEREO\n");
01150                 break;
01151             case JOINT_STEREO:
01152                 if (q->nb_channels != 2) {
01153                     av_log(avctx,AV_LOG_ERROR,"Container channels != 2, report sample!\n");
01154                     return -1;
01155                 }
01156                 av_log(avctx,AV_LOG_DEBUG,"JOINT_STEREO\n");
01157                 if (avctx->extradata_size >= 16){
01158                     q->subpacket[s].total_subbands = q->subpacket[s].subbands + q->subpacket[s].js_subband_start;
01159                     q->subpacket[s].joint_stereo = 1;
01160                     q->subpacket[s].num_channels = 2;
01161                 }
01162                 if (q->subpacket[s].samples_per_channel > 256) {
01163                     q->subpacket[s].log2_numvector_size  = 6;
01164                 }
01165                 if (q->subpacket[s].samples_per_channel > 512) {
01166                     q->subpacket[s].log2_numvector_size  = 7;
01167                 }
01168                 break;
01169             case MC_COOK:
01170                 av_log(avctx,AV_LOG_DEBUG,"MULTI_CHANNEL\n");
01171                 if(extradata_size >= 4)
01172                     channel_mask |= q->subpacket[s].channel_mask = bytestream_get_be32(&edata_ptr);
01173 
01174                 if(cook_count_channels(q->subpacket[s].channel_mask) > 1){
01175                     q->subpacket[s].total_subbands = q->subpacket[s].subbands + q->subpacket[s].js_subband_start;
01176                     q->subpacket[s].joint_stereo = 1;
01177                     q->subpacket[s].num_channels = 2;
01178                     q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame >> 1;
01179 
01180                     if (q->subpacket[s].samples_per_channel > 256) {
01181                         q->subpacket[s].log2_numvector_size  = 6;
01182                     }
01183                     if (q->subpacket[s].samples_per_channel > 512) {
01184                         q->subpacket[s].log2_numvector_size  = 7;
01185                     }
01186                 }else
01187                     q->subpacket[s].samples_per_channel = q->subpacket[s].samples_per_frame;
01188 
01189                 break;
01190             default:
01191                 av_log(avctx,AV_LOG_ERROR,"Unknown Cook version, report sample!\n");
01192                 return -1;
01193                 break;
01194         }
01195 
01196         if(s > 1 && q->subpacket[s].samples_per_channel != q->samples_per_channel) {
01197             av_log(avctx,AV_LOG_ERROR,"different number of samples per channel!\n");
01198             return -1;
01199         } else
01200             q->samples_per_channel = q->subpacket[0].samples_per_channel;
01201 
01202 
01203         /* Initialize variable relations */
01204         q->subpacket[s].numvector_size = (1 << q->subpacket[s].log2_numvector_size);
01205 
01206         /* Try to catch some obviously faulty streams, othervise it might be exploitable */
01207         if (q->subpacket[s].total_subbands > 53) {
01208             av_log(avctx,AV_LOG_ERROR,"total_subbands > 53, report sample!\n");
01209             return -1;
01210         }
01211 
01212         if ((q->subpacket[s].js_vlc_bits > 6) || (q->subpacket[s].js_vlc_bits < 0)) {
01213             av_log(avctx,AV_LOG_ERROR,"js_vlc_bits = %d, only >= 0 and <= 6 allowed!\n",q->subpacket[s].js_vlc_bits);
01214             return -1;
01215         }
01216 
01217         if (q->subpacket[s].subbands > 50) {
01218             av_log(avctx,AV_LOG_ERROR,"subbands > 50, report sample!\n");
01219             return -1;
01220         }
01221         q->subpacket[s].gains1.now      = q->subpacket[s].gain_1;
01222         q->subpacket[s].gains1.previous = q->subpacket[s].gain_2;
01223         q->subpacket[s].gains2.now      = q->subpacket[s].gain_3;
01224         q->subpacket[s].gains2.previous = q->subpacket[s].gain_4;
01225 
01226         q->num_subpackets++;
01227         s++;
01228         if (s > MAX_SUBPACKETS) {
01229             av_log(avctx,AV_LOG_ERROR,"Too many subpackets > 5, report file!\n");
01230             return -1;
01231         }
01232     }
01233     /* Generate tables */
01234     init_pow2table();
01235     init_gain_table(q);
01236     init_cplscales_table(q);
01237 
01238     if (init_cook_vlc_tables(q) != 0)
01239         return -1;
01240 
01241 
01242     if(avctx->block_align >= UINT_MAX/2)
01243         return -1;
01244 
01245     /* Pad the databuffer with:
01246        DECODE_BYTES_PAD1 or DECODE_BYTES_PAD2 for decode_bytes(),
01247        FF_INPUT_BUFFER_PADDING_SIZE, for the bitstreamreader. */
01248         q->decoded_bytes_buffer =
01249           av_mallocz(avctx->block_align
01250                      + DECODE_BYTES_PAD1(avctx->block_align)
01251                      + FF_INPUT_BUFFER_PADDING_SIZE);
01252     if (q->decoded_bytes_buffer == NULL)
01253         return -1;
01254 
01255     /* Initialize transform. */
01256     if ( init_cook_mlt(q) != 0 )
01257         return -1;
01258 
01259     /* Initialize COOK signal arithmetic handling */
01260     if (1) {
01261         q->scalar_dequant  = scalar_dequant_float;
01262         q->decouple        = decouple_float;
01263         q->imlt_window     = imlt_window_float;
01264         q->interpolate     = interpolate_float;
01265         q->saturate_output = saturate_output_float;
01266     }
01267 
01268     /* Try to catch some obviously faulty streams, othervise it might be exploitable */
01269     if ((q->samples_per_channel == 256) || (q->samples_per_channel == 512) || (q->samples_per_channel == 1024)) {
01270     } else {
01271         av_log(avctx,AV_LOG_ERROR,"unknown amount of samples_per_channel = %d, report sample!\n",q->samples_per_channel);
01272         return -1;
01273     }
01274 
01275     avctx->sample_fmt = SAMPLE_FMT_S16;
01276     if (channel_mask)
01277         avctx->channel_layout = channel_mask;
01278     else
01279         avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
01280 
01281 #ifdef COOKDEBUG
01282     dump_cook_context(q);
01283 #endif
01284     return 0;
01285 }
01286 
01287 
01288 AVCodec cook_decoder =
01289 {
01290     .name = "cook",
01291     .type = AVMEDIA_TYPE_AUDIO,
01292     .id = CODEC_ID_COOK,
01293     .priv_data_size = sizeof(COOKContext),
01294     .init = cook_decode_init,
01295     .close = cook_decode_close,
01296     .decode = cook_decode_frame,
01297     .long_name = NULL_IF_CONFIG_SMALL("COOK"),
01298 };

Generated on Fri Sep 16 2011 17:17:34 for FFmpeg by  doxygen 1.7.1