1/*
2 * COOK compatible decoder
3 * Copyright (c) 2003 Sascha Sommer
4 * Copyright (c) 2005 Benjamin Larsson
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file libavcodec/cook.c
25 * Cook compatible decoder. Bastardization of the G.722.1 standard.
26 * This decoder handles RealNetworks, RealAudio G2 data.
27 * Cook is identified by the codec name cook in RM files.
28 *
29 * To use this decoder, a calling application must supply the extradata
30 * bytes provided from the RM container; 8+ bytes for mono streams and
31 * 16+ for stereo streams (maybe more).
32 *
33 * Codec technicalities (all this assume a buffer length of 1024):
34 * Cook works with several different techniques to achieve its compression.
35 * In the timedomain the buffer is divided into 8 pieces and quantized. If
36 * two neighboring pieces have different quantization index a smooth
37 * quantization curve is used to get a smooth overlap between the different
38 * pieces.
39 * To get to the transformdomain Cook uses a modulated lapped transform.
40 * The transform domain has 50 subbands with 20 elements each. This
41 * means only a maximum of 50*20=1000 coefficients are used out of the 1024
42 * available.
43 */
44
45#include <math.h>
46#include <stddef.h>
47#include <stdio.h>
48
49#include "libavutil/random.h"
50#include "avcodec.h"
51#include "bitstream.h"
52#include "dsputil.h"
53#include "bytestream.h"
54
55#include "cookdata.h"
56
57/* the different Cook versions */
58#define MONO            0x1000001
59#define STEREO          0x1000002
60#define JOINT_STEREO    0x1000003
61#define MC_COOK         0x2000000   //multichannel Cook, not supported
62
63#define SUBBAND_SIZE    20
64//#define COOKDEBUG
65
66typedef struct {
67    int *now;
68    int *previous;
69} cook_gains;
70
71typedef struct cook {
72    /*
73     * The following 5 functions provide the lowlevel arithmetic on
74     * the internal audio buffers.
75     */
76    void (* scalar_dequant)(struct cook *q, int index, int quant_index,
77                            int* subband_coef_index, int* subband_coef_sign,
78                            float* mlt_p);
79
80    void (* decouple) (struct cook *q,
81                       int subband,
82                       float f1, float f2,
83                       float *decode_buffer,
84                       float *mlt_buffer1, float *mlt_buffer2);
85
86    void (* imlt_window) (struct cook *q, float *buffer1,
87                          cook_gains *gains_ptr, float *previous_buffer);
88
89    void (* interpolate) (struct cook *q, float* buffer,
90                          int gain_index, int gain_index_next);
91
92    void (* saturate_output) (struct cook *q, int chan, int16_t *out);
93
94    GetBitContext       gb;
95    /* stream data */
96    int                 nb_channels;
97    int                 joint_stereo;
98    int                 bit_rate;
99    int                 sample_rate;
100    int                 samples_per_channel;
101    int                 samples_per_frame;
102    int                 subbands;
103    int                 log2_numvector_size;
104    int                 numvector_size;                //1 << log2_numvector_size;
105    int                 js_subband_start;
106    int                 total_subbands;
107    int                 num_vectors;
108    int                 bits_per_subpacket;
109    int                 cookversion;
110    /* states */
111    AVRandomState       random_state;
112
113    /* transform data */
114    MDCTContext         mdct_ctx;
115    float*              mlt_window;
116
117    /* gain buffers */
118    cook_gains          gains1;
119    cook_gains          gains2;
120    int                 gain_1[9];
121    int                 gain_2[9];
122    int                 gain_3[9];
123    int                 gain_4[9];
124
125    /* VLC data */
126    int                 js_vlc_bits;
127    VLC                 envelope_quant_index[13];
128    VLC                 sqvh[7];          //scalar quantization
129    VLC                 ccpl;             //channel coupling
130
131    /* generatable tables and related variables */
132    int                 gain_size_factor;
133    float               gain_table[23];
134
135    /* data buffers */
136
137    uint8_t*            decoded_bytes_buffer;
138    DECLARE_ALIGNED_16(float,mono_mdct_output[2048]);
139    float               mono_previous_buffer1[1024];
140    float               mono_previous_buffer2[1024];
141    float               decode_buffer_1[1024];
142    float               decode_buffer_2[1024];
143    float               decode_buffer_0[1060]; /* static allocation for joint decode */
144
145    const float         *cplscales[5];
146} COOKContext;
147
148static float     pow2tab[127];
149static float rootpow2tab[127];
150
151/* debug functions */
152
153#ifdef COOKDEBUG
154static void dump_float_table(float* table, int size, int delimiter) {
155    int i=0;
156    av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
157    for (i=0 ; i<size ; i++) {
158        av_log(NULL, AV_LOG_ERROR, "%5.1f, ", table[i]);
159        if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
160    }
161}
162
163static void dump_int_table(int* table, int size, int delimiter) {
164    int i=0;
165    av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
166    for (i=0 ; i<size ; i++) {
167        av_log(NULL, AV_LOG_ERROR, "%d, ", table[i]);
168        if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
169    }
170}
171
172static void dump_short_table(short* table, int size, int delimiter) {
173    int i=0;
174    av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i);
175    for (i=0 ; i<size ; i++) {
176        av_log(NULL, AV_LOG_ERROR, "%d, ", table[i]);
177        if ((i+1)%delimiter == 0) av_log(NULL,AV_LOG_ERROR,"\n[%d]: ",i+1);
178    }
179}
180
181#endif
182
183/*************** init functions ***************/
184
185/* table generator */
186static av_cold void init_pow2table(void){
187    int i;
188    for (i=-63 ; i<64 ; i++){
189            pow2tab[63+i]=     pow(2, i);
190        rootpow2tab[63+i]=sqrt(pow(2, i));
191    }
192}
193
194/* table generator */
195static av_cold void init_gain_table(COOKContext *q) {
196    int i;
197    q->gain_size_factor = q->samples_per_channel/8;
198    for (i=0 ; i<23 ; i++) {
199        q->gain_table[i] = pow(pow2tab[i+52] ,
200                               (1.0/(double)q->gain_size_factor));
201    }
202}
203
204
205static av_cold int init_cook_vlc_tables(COOKContext *q) {
206    int i, result;
207
208    result = 0;
209    for (i=0 ; i<13 ; i++) {
210        result |= init_vlc (&q->envelope_quant_index[i], 9, 24,
211            envelope_quant_index_huffbits[i], 1, 1,
212            envelope_quant_index_huffcodes[i], 2, 2, 0);
213    }
214    av_log(NULL,AV_LOG_DEBUG,"sqvh VLC init\n");
215    for (i=0 ; i<7 ; i++) {
216        result |= init_vlc (&q->sqvh[i], vhvlcsize_tab[i], vhsize_tab[i],
217            cvh_huffbits[i], 1, 1,
218            cvh_huffcodes[i], 2, 2, 0);
219    }
220
221    if (q->nb_channels==2 && q->joint_stereo==1){
222        result |= init_vlc (&q->ccpl, 6, (1<<q->js_vlc_bits)-1,
223            ccpl_huffbits[q->js_vlc_bits-2], 1, 1,
224            ccpl_huffcodes[q->js_vlc_bits-2], 2, 2, 0);
225        av_log(NULL,AV_LOG_DEBUG,"Joint-stereo VLC used.\n");
226    }
227
228    av_log(NULL,AV_LOG_DEBUG,"VLC tables initialized.\n");
229    return result;
230}
231
232static av_cold int init_cook_mlt(COOKContext *q) {
233    int j;
234    int mlt_size = q->samples_per_channel;
235
236    if ((q->mlt_window = av_malloc(sizeof(float)*mlt_size)) == 0)
237      return -1;
238
239    /* Initialize the MLT window: simple sine window. */
240    ff_sine_window_init(q->mlt_window, mlt_size);
241    for(j=0 ; j<mlt_size ; j++)
242        q->mlt_window[j] *= sqrt(2.0 / q->samples_per_channel);
243
244    /* Initialize the MDCT. */
245    if (ff_mdct_init(&q->mdct_ctx, av_log2(mlt_size)+1, 1)) {
246      av_free(q->mlt_window);
247      return -1;
248    }
249    av_log(NULL,AV_LOG_DEBUG,"MDCT initialized, order = %d.\n",
250           av_log2(mlt_size)+1);
251
252    return 0;
253}
254
255static const float *maybe_reformat_buffer32 (COOKContext *q, const float *ptr, int n)
256{
257    if (1)
258        return ptr;
259}
260
261static av_cold void init_cplscales_table (COOKContext *q) {
262    int i;
263    for (i=0;i<5;i++)
264        q->cplscales[i] = maybe_reformat_buffer32 (q, cplscales[i], (1<<(i+2))-1);
265}
266
267/*************** init functions end ***********/
268
269/**
270 * Cook indata decoding, every 32 bits are XORed with 0x37c511f2.
271 * Why? No idea, some checksum/error detection method maybe.
272 *
273 * Out buffer size: extra bytes are needed to cope with
274 * padding/misalignment.
275 * Subpackets passed to the decoder can contain two, consecutive
276 * half-subpackets, of identical but arbitrary size.
277 *          1234 1234 1234 1234  extraA extraB
278 * Case 1:  AAAA BBBB              0      0
279 * Case 2:  AAAA ABBB BB--         3      3
280 * Case 3:  AAAA AABB BBBB         2      2
281 * Case 4:  AAAA AAAB BBBB BB--    1      5
282 *
283 * Nice way to waste CPU cycles.
284 *
285 * @param inbuffer  pointer to byte array of indata
286 * @param out       pointer to byte array of outdata
287 * @param bytes     number of bytes
288 */
289#define DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
290#define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
291
292static inline int decode_bytes(const uint8_t* inbuffer, uint8_t* out, int bytes){
293    int i, off;
294    uint32_t c;
295    const uint32_t* buf;
296    uint32_t* obuf = (uint32_t*) out;
297    /* FIXME: 64 bit platforms would be able to do 64 bits at a time.
298     * I'm too lazy though, should be something like
299     * for(i=0 ; i<bitamount/64 ; i++)
300     *     (int64_t)out[i] = 0x37c511f237c511f2^be2me_64(int64_t)in[i]);
301     * Buffer alignment needs to be checked. */
302
303    off = (int)((long)inbuffer & 3);
304    buf = (const uint32_t*) (inbuffer - off);
305    c = be2me_32((0x37c511f2 >> (off*8)) | (0x37c511f2 << (32-(off*8))));
306    bytes += 3 + off;
307    for (i = 0; i < bytes/4; i++)
308        obuf[i] = c ^ buf[i];
309
310    return off;
311}
312
313/**
314 * Cook uninit
315 */
316
317static av_cold int cook_decode_close(AVCodecContext *avctx)
318{
319    int i;
320    COOKContext *q = avctx->priv_data;
321    av_log(avctx,AV_LOG_DEBUG, "Deallocating memory.\n");
322
323    /* Free allocated memory buffers. */
324    av_free(q->mlt_window);
325    av_free(q->decoded_bytes_buffer);
326
327    /* Free the transform. */
328    ff_mdct_end(&q->mdct_ctx);
329
330    /* Free the VLC tables. */
331    for (i=0 ; i<13 ; i++) {
332        free_vlc(&q->envelope_quant_index[i]);
333    }
334    for (i=0 ; i<7 ; i++) {
335        free_vlc(&q->sqvh[i]);
336    }
337    if(q->nb_channels==2 && q->joint_stereo==1 ){
338        free_vlc(&q->ccpl);
339    }
340
341    av_log(NULL,AV_LOG_DEBUG,"Memory deallocated.\n");
342
343    return 0;
344}
345
346/**
347 * Fill the gain array for the timedomain quantization.
348 *
349 * @param q                 pointer to the COOKContext
350 * @param gaininfo[9]       array of gain indexes
351 */
352
353static void decode_gain_info(GetBitContext *gb, int *gaininfo)
354{
355    int i, n;
356
357    while (get_bits1(gb)) {}
358    n = get_bits_count(gb) - 1;     //amount of elements*2 to update
359
360    i = 0;
361    while (n--) {
362        int index = get_bits(gb, 3);
363        int gain = get_bits1(gb) ? get_bits(gb, 4) - 7 : -1;
364
365        while (i <= index) gaininfo[i++] = gain;
366    }
367    while (i <= 8) gaininfo[i++] = 0;
368}
369
370/**
371 * Create the quant index table needed for the envelope.
372 *
373 * @param q                 pointer to the COOKContext
374 * @param quant_index_table pointer to the array
375 */
376
377static void decode_envelope(COOKContext *q, int* quant_index_table) {
378    int i,j, vlc_index;
379
380    quant_index_table[0]= get_bits(&q->gb,6) - 6;       //This is used later in categorize
381
382    for (i=1 ; i < q->total_subbands ; i++){
383        vlc_index=i;
384        if (i >= q->js_subband_start * 2) {
385            vlc_index-=q->js_subband_start;
386        } else {
387            vlc_index/=2;
388            if(vlc_index < 1) vlc_index = 1;
389        }
390        if (vlc_index>13) vlc_index = 13;           //the VLC tables >13 are identical to No. 13
391
392        j = get_vlc2(&q->gb, q->envelope_quant_index[vlc_index-1].table,
393                     q->envelope_quant_index[vlc_index-1].bits,2);
394        quant_index_table[i] = quant_index_table[i-1] + j - 12;    //differential encoding
395    }
396}
397
398/**
399 * Calculate the category and category_index vector.
400 *
401 * @param q                     pointer to the COOKContext
402 * @param quant_index_table     pointer to the array
403 * @param category              pointer to the category array
404 * @param category_index        pointer to the category_index array
405 */
406
407static void categorize(COOKContext *q, int* quant_index_table,
408                       int* category, int* category_index){
409    int exp_idx, bias, tmpbias1, tmpbias2, bits_left, num_bits, index, v, i, j;
410    int exp_index2[102];
411    int exp_index1[102];
412
413    int tmp_categorize_array[128*2];
414    int tmp_categorize_array1_idx=q->numvector_size;
415    int tmp_categorize_array2_idx=q->numvector_size;
416
417    bits_left =  q->bits_per_subpacket - get_bits_count(&q->gb);
418
419    if(bits_left > q->samples_per_channel) {
420        bits_left = q->samples_per_channel +
421                    ((bits_left - q->samples_per_channel)*5)/8;
422        //av_log(NULL, AV_LOG_ERROR, "bits_left = %d\n",bits_left);
423    }
424
425    memset(&exp_index1,0,102*sizeof(int));
426    memset(&exp_index2,0,102*sizeof(int));
427    memset(&tmp_categorize_array,0,128*2*sizeof(int));
428
429    bias=-32;
430
431    /* Estimate bias. */
432    for (i=32 ; i>0 ; i=i/2){
433        num_bits = 0;
434        index = 0;
435        for (j=q->total_subbands ; j>0 ; j--){
436            exp_idx = av_clip((i - quant_index_table[index] + bias) / 2, 0, 7);
437            index++;
438            num_bits+=expbits_tab[exp_idx];
439        }
440        if(num_bits >= bits_left - 32){
441            bias+=i;
442        }
443    }
444
445    /* Calculate total number of bits. */
446    num_bits=0;
447    for (i=0 ; i<q->total_subbands ; i++) {
448        exp_idx = av_clip((bias - quant_index_table[i]) / 2, 0, 7);
449        num_bits += expbits_tab[exp_idx];
450        exp_index1[i] = exp_idx;
451        exp_index2[i] = exp_idx;
452    }
453    tmpbias1 = tmpbias2 = num_bits;
454
455    for (j = 1 ; j < q->numvector_size ; j++) {
456        if (tmpbias1 + tmpbias2 > 2*bits_left) {  /* ---> */
457            int max = -999999;
458            index=-1;
459            for (i=0 ; i<q->total_subbands ; i++){
460                if (exp_index1[i] < 7) {
461                    v = (-2*exp_index1[i]) - quant_index_table[i] + bias;
462                    if ( v >= max) {
463                        max = v;
464                        index = i;
465                    }
466                }
467            }
468            if(index==-1)break;
469            tmp_categorize_array[tmp_categorize_array1_idx++] = index;
470            tmpbias1 -= expbits_tab[exp_index1[index]] -
471                        expbits_tab[exp_index1[index]+1];
472            ++exp_index1[index];
473        } else {  /* <--- */
474            int min = 999999;
475            index=-1;
476            for (i=0 ; i<q->total_subbands ; i++){
477                if(exp_index2[i] > 0){
478                    v = (-2*exp_index2[i])-quant_index_table[i]+bias;
479                    if ( v < min) {
480                        min = v;
481                        index = i;
482                    }
483                }
484            }
485            if(index == -1)break;
486            tmp_categorize_array[--tmp_categorize_array2_idx] = index;
487            tmpbias2 -= expbits_tab[exp_index2[index]] -
488                        expbits_tab[exp_index2[index]-1];
489            --exp_index2[index];
490        }
491    }
492
493    for(i=0 ; i<q->total_subbands ; i++)
494        category[i] = exp_index2[i];
495
496    for(i=0 ; i<q->numvector_size-1 ; i++)
497        category_index[i] = tmp_categorize_array[tmp_categorize_array2_idx++];
498
499}
500
501
502/**
503 * Expand the category vector.
504 *
505 * @param q                     pointer to the COOKContext
506 * @param category              pointer to the category array
507 * @param category_index        pointer to the category_index array
508 */
509
510static inline void expand_category(COOKContext *q, int* category,
511                                   int* category_index){
512    int i;
513    for(i=0 ; i<q->num_vectors ; i++){
514        ++category[category_index[i]];
515    }
516}
517
518/**
519 * The real requantization of the mltcoefs
520 *
521 * @param q                     pointer to the COOKContext
522 * @param index                 index
523 * @param quant_index           quantisation index
524 * @param subband_coef_index    array of indexes to quant_centroid_tab
525 * @param subband_coef_sign     signs of coefficients
526 * @param mlt_p                 pointer into the mlt buffer
527 */
528
529static void scalar_dequant_float(COOKContext *q, int index, int quant_index,
530                           int* subband_coef_index, int* subband_coef_sign,
531                           float* mlt_p){
532    int i;
533    float f1;
534
535    for(i=0 ; i<SUBBAND_SIZE ; i++) {
536        if (subband_coef_index[i]) {
537            f1 = quant_centroid_tab[index][subband_coef_index[i]];
538            if (subband_coef_sign[i]) f1 = -f1;
539        } else {
540            /* noise coding if subband_coef_index[i] == 0 */
541            f1 = dither_tab[index];
542            if (av_random(&q->random_state) < 0x80000000) f1 = -f1;
543        }
544        mlt_p[i] = f1 * rootpow2tab[quant_index+63];
545    }
546}
547/**
548 * Unpack the subband_coef_index and subband_coef_sign vectors.
549 *
550 * @param q                     pointer to the COOKContext
551 * @param category              pointer to the category array
552 * @param subband_coef_index    array of indexes to quant_centroid_tab
553 * @param subband_coef_sign     signs of coefficients
554 */
555
556static int unpack_SQVH(COOKContext *q, int category, int* subband_coef_index,
557                       int* subband_coef_sign) {
558    int i,j;
559    int vlc, vd ,tmp, result;
560
561    vd = vd_tab[category];
562    result = 0;
563    for(i=0 ; i<vpr_tab[category] ; i++){
564        vlc = get_vlc2(&q->gb, q->sqvh[category].table, q->sqvh[category].bits, 3);
565        if (q->bits_per_subpacket < get_bits_count(&q->gb)){
566            vlc = 0;
567            result = 1;
568        }
569        for(j=vd-1 ; j>=0 ; j--){
570            tmp = (vlc * invradix_tab[category])/0x100000;
571            subband_coef_index[vd*i+j] = vlc - tmp * (kmax_tab[category]+1);
572            vlc = tmp;
573        }
574        for(j=0 ; j<vd ; j++){
575            if (subband_coef_index[i*vd + j]) {
576                if(get_bits_count(&q->gb) < q->bits_per_subpacket){
577                    subband_coef_sign[i*vd+j] = get_bits1(&q->gb);
578                } else {
579                    result=1;
580                    subband_coef_sign[i*vd+j]=0;
581                }
582            } else {
583                subband_coef_sign[i*vd+j]=0;
584            }
585        }
586    }
587    return result;
588}
589
590
591/**
592 * Fill the mlt_buffer with mlt coefficients.
593 *
594 * @param q                 pointer to the COOKContext
595 * @param category          pointer to the category array
596 * @param quant_index_table pointer to the array
597 * @param mlt_buffer        pointer to mlt coefficients
598 */
599
600
601static void decode_vectors(COOKContext* q, int* category,
602                           int *quant_index_table, float* mlt_buffer){
603    /* A zero in this table means that the subband coefficient is
604       random noise coded. */
605    int subband_coef_index[SUBBAND_SIZE];
606    /* A zero in this table means that the subband coefficient is a
607       positive multiplicator. */
608    int subband_coef_sign[SUBBAND_SIZE];
609    int band, j;
610    int index=0;
611
612    for(band=0 ; band<q->total_subbands ; band++){
613        index = category[band];
614        if(category[band] < 7){
615            if(unpack_SQVH(q, category[band], subband_coef_index, subband_coef_sign)){
616                index=7;
617                for(j=0 ; j<q->total_subbands ; j++) category[band+j]=7;
618            }
619        }
620        if(index==7) {
621            memset(subband_coef_index, 0, sizeof(subband_coef_index));
622            memset(subband_coef_sign, 0, sizeof(subband_coef_sign));
623        }
624        q->scalar_dequant(q, index, quant_index_table[band],
625                          subband_coef_index, subband_coef_sign,
626                          &mlt_buffer[band * SUBBAND_SIZE]);
627    }
628
629    if(q->total_subbands*SUBBAND_SIZE >= q->samples_per_channel){
630        return;
631    } /* FIXME: should this be removed, or moved into loop above? */
632}
633
634
635/**
636 * function for decoding mono data
637 *
638 * @param q                 pointer to the COOKContext
639 * @param mlt_buffer        pointer to mlt coefficients
640 */
641
642static void mono_decode(COOKContext *q, float* mlt_buffer) {
643
644    int category_index[128];
645    int quant_index_table[102];
646    int category[128];
647
648    memset(&category, 0, 128*sizeof(int));
649    memset(&category_index, 0, 128*sizeof(int));
650
651    decode_envelope(q, quant_index_table);
652    q->num_vectors = get_bits(&q->gb,q->log2_numvector_size);
653    categorize(q, quant_index_table, category, category_index);
654    expand_category(q, category, category_index);
655    decode_vectors(q, category, quant_index_table, mlt_buffer);
656}
657
658
659/**
660 * the actual requantization of the timedomain samples
661 *
662 * @param q                 pointer to the COOKContext
663 * @param buffer            pointer to the timedomain buffer
664 * @param gain_index        index for the block multiplier
665 * @param gain_index_next   index for the next block multiplier
666 */
667
668static void interpolate_float(COOKContext *q, float* buffer,
669                        int gain_index, int gain_index_next){
670    int i;
671    float fc1, fc2;
672    fc1 = pow2tab[gain_index+63];
673
674    if(gain_index == gain_index_next){              //static gain
675        for(i=0 ; i<q->gain_size_factor ; i++){
676            buffer[i]*=fc1;
677        }
678        return;
679    } else {                                        //smooth gain
680        fc2 = q->gain_table[11 + (gain_index_next-gain_index)];
681        for(i=0 ; i<q->gain_size_factor ; i++){
682            buffer[i]*=fc1;
683            fc1*=fc2;
684        }
685        return;
686    }
687}
688
689/**
690 * Apply transform window, overlap buffers.
691 *
692 * @param q                 pointer to the COOKContext
693 * @param inbuffer          pointer to the mltcoefficients
694 * @param gains_ptr         current and previous gains
695 * @param previous_buffer   pointer to the previous buffer to be used for overlapping
696 */
697
698static void imlt_window_float (COOKContext *q, float *buffer1,
699                               cook_gains *gains_ptr, float *previous_buffer)
700{
701    const float fc = pow2tab[gains_ptr->previous[0] + 63];
702    int i;
703    /* The weird thing here, is that the two halves of the time domain
704     * buffer are swapped. Also, the newest data, that we save away for
705     * next frame, has the wrong sign. Hence the subtraction below.
706     * Almost sounds like a complex conjugate/reverse data/FFT effect.
707     */
708
709    /* Apply window and overlap */
710    for(i = 0; i < q->samples_per_channel; i++){
711        buffer1[i] = buffer1[i] * fc * q->mlt_window[i] -
712          previous_buffer[i] * q->mlt_window[q->samples_per_channel - 1 - i];
713    }
714}
715
716/**
717 * The modulated lapped transform, this takes transform coefficients
718 * and transforms them into timedomain samples.
719 * Apply transform window, overlap buffers, apply gain profile
720 * and buffer management.
721 *
722 * @param q                 pointer to the COOKContext
723 * @param inbuffer          pointer to the mltcoefficients
724 * @param gains_ptr         current and previous gains
725 * @param previous_buffer   pointer to the previous buffer to be used for overlapping
726 */
727
728static void imlt_gain(COOKContext *q, float *inbuffer,
729                      cook_gains *gains_ptr, float* previous_buffer)
730{
731    float *buffer0 = q->mono_mdct_output;
732    float *buffer1 = q->mono_mdct_output + q->samples_per_channel;
733    int i;
734
735    /* Inverse modified discrete cosine transform */
736    ff_imdct_calc(&q->mdct_ctx, q->mono_mdct_output, inbuffer);
737
738    q->imlt_window (q, buffer1, gains_ptr, previous_buffer);
739
740    /* Apply gain profile */
741    for (i = 0; i < 8; i++) {
742        if (gains_ptr->now[i] || gains_ptr->now[i + 1])
743            q->interpolate(q, &buffer1[q->gain_size_factor * i],
744                           gains_ptr->now[i], gains_ptr->now[i + 1]);
745    }
746
747    /* Save away the current to be previous block. */
748    memcpy(previous_buffer, buffer0, sizeof(float)*q->samples_per_channel);
749}
750
751
752/**
753 * function for getting the jointstereo coupling information
754 *
755 * @param q                 pointer to the COOKContext
756 * @param decouple_tab      decoupling array
757 *
758 */
759
760static void decouple_info(COOKContext *q, int* decouple_tab){
761    int length, i;
762
763    if(get_bits1(&q->gb)) {
764        if(cplband[q->js_subband_start] > cplband[q->subbands-1]) return;
765
766        length = cplband[q->subbands-1] - cplband[q->js_subband_start] + 1;
767        for (i=0 ; i<length ; i++) {
768            decouple_tab[cplband[q->js_subband_start] + i] = get_vlc2(&q->gb, q->ccpl.table, q->ccpl.bits, 2);
769        }
770        return;
771    }
772
773    if(cplband[q->js_subband_start] > cplband[q->subbands-1]) return;
774
775    length = cplband[q->subbands-1] - cplband[q->js_subband_start] + 1;
776    for (i=0 ; i<length ; i++) {
777       decouple_tab[cplband[q->js_subband_start] + i] = get_bits(&q->gb, q->js_vlc_bits);
778    }
779    return;
780}
781
782/*
783 * function decouples a pair of signals from a single signal via multiplication.
784 *
785 * @param q                 pointer to the COOKContext
786 * @param subband           index of the current subband
787 * @param f1                multiplier for channel 1 extraction
788 * @param f2                multiplier for channel 2 extraction
789 * @param decode_buffer     input buffer
790 * @param mlt_buffer1       pointer to left channel mlt coefficients
791 * @param mlt_buffer2       pointer to right channel mlt coefficients
792 */
793static void decouple_float (COOKContext *q,
794                            int subband,
795                            float f1, float f2,
796                            float *decode_buffer,
797                            float *mlt_buffer1, float *mlt_buffer2)
798{
799    int j, tmp_idx;
800    for (j=0 ; j<SUBBAND_SIZE ; j++) {
801        tmp_idx = ((q->js_subband_start + subband)*SUBBAND_SIZE)+j;
802        mlt_buffer1[SUBBAND_SIZE*subband + j] = f1 * decode_buffer[tmp_idx];
803        mlt_buffer2[SUBBAND_SIZE*subband + j] = f2 * decode_buffer[tmp_idx];
804    }
805}
806
807/**
808 * function for decoding joint stereo data
809 *
810 * @param q                 pointer to the COOKContext
811 * @param mlt_buffer1       pointer to left channel mlt coefficients
812 * @param mlt_buffer2       pointer to right channel mlt coefficients
813 */
814
815static void joint_decode(COOKContext *q, float* mlt_buffer1,
816                         float* mlt_buffer2) {
817    int i,j;
818    int decouple_tab[SUBBAND_SIZE];
819    float *decode_buffer = q->decode_buffer_0;
820    int idx, cpl_tmp;
821    float f1,f2;
822    const float* cplscale;
823
824    memset(decouple_tab, 0, sizeof(decouple_tab));
825    memset(decode_buffer, 0, sizeof(decode_buffer));
826
827    /* Make sure the buffers are zeroed out. */
828    memset(mlt_buffer1,0, 1024*sizeof(float));
829    memset(mlt_buffer2,0, 1024*sizeof(float));
830    decouple_info(q, decouple_tab);
831    mono_decode(q, decode_buffer);
832
833    /* The two channels are stored interleaved in decode_buffer. */
834    for (i=0 ; i<q->js_subband_start ; i++) {
835        for (j=0 ; j<SUBBAND_SIZE ; j++) {
836            mlt_buffer1[i*20+j] = decode_buffer[i*40+j];
837            mlt_buffer2[i*20+j] = decode_buffer[i*40+20+j];
838        }
839    }
840
841    /* When we reach js_subband_start (the higher frequencies)
842       the coefficients are stored in a coupling scheme. */
843    idx = (1 << q->js_vlc_bits) - 1;
844    for (i=q->js_subband_start ; i<q->subbands ; i++) {
845        cpl_tmp = cplband[i];
846        idx -=decouple_tab[cpl_tmp];
847        cplscale = q->cplscales[q->js_vlc_bits-2];  //choose decoupler table
848        f1 = cplscale[decouple_tab[cpl_tmp]];
849        f2 = cplscale[idx-1];
850        q->decouple (q, i, f1, f2, decode_buffer, mlt_buffer1, mlt_buffer2);
851        idx = (1 << q->js_vlc_bits) - 1;
852    }
853}
854
855/**
856 * First part of subpacket decoding:
857 *  decode raw stream bytes and read gain info.
858 *
859 * @param q                 pointer to the COOKContext
860 * @param inbuffer          pointer to raw stream data
861 * @param gain_ptr          array of current/prev gain pointers
862 */
863
864static inline void
865decode_bytes_and_gain(COOKContext *q, const uint8_t *inbuffer,
866                      cook_gains *gains_ptr)
867{
868    int offset;
869
870    offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
871                          q->bits_per_subpacket/8);
872    init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
873                  q->bits_per_subpacket);
874    decode_gain_info(&q->gb, gains_ptr->now);
875
876    /* Swap current and previous gains */
877    FFSWAP(int *, gains_ptr->now, gains_ptr->previous);
878}
879
880 /**
881 * Saturate the output signal to signed 16bit integers.
882 *
883 * @param q                 pointer to the COOKContext
884 * @param chan              channel to saturate
885 * @param out               pointer to the output vector
886 */
887static void
888saturate_output_float (COOKContext *q, int chan, int16_t *out)
889{
890    int j;
891    float *output = q->mono_mdct_output + q->samples_per_channel;
892    /* Clip and convert floats to 16 bits.
893     */
894    for (j = 0; j < q->samples_per_channel; j++) {
895        out[chan + q->nb_channels * j] =
896          av_clip_int16(lrintf(output[j]));
897    }
898}
899
900/**
901 * Final part of subpacket decoding:
902 *  Apply modulated lapped transform, gain compensation,
903 *  clip and convert to integer.
904 *
905 * @param q                 pointer to the COOKContext
906 * @param decode_buffer     pointer to the mlt coefficients
907 * @param gain_ptr          array of current/prev gain pointers
908 * @param previous_buffer   pointer to the previous buffer to be used for overlapping
909 * @param out               pointer to the output buffer
910 * @param chan              0: left or single channel, 1: right channel
911 */
912
913static inline void
914mlt_compensate_output(COOKContext *q, float *decode_buffer,
915                      cook_gains *gains, float *previous_buffer,
916                      int16_t *out, int chan)
917{
918    imlt_gain(q, decode_buffer, gains, previous_buffer);
919    q->saturate_output (q, chan, out);
920}
921
922
923/**
924 * Cook subpacket decoding. This function returns one decoded subpacket,
925 * usually 1024 samples per channel.
926 *
927 * @param q                 pointer to the COOKContext
928 * @param inbuffer          pointer to the inbuffer
929 * @param sub_packet_size   subpacket size
930 * @param outbuffer         pointer to the outbuffer
931 */
932
933
934static int decode_subpacket(COOKContext *q, const uint8_t *inbuffer,
935                            int sub_packet_size, int16_t *outbuffer) {
936    /* packet dump */
937//    for (i=0 ; i<sub_packet_size ; i++) {
938//        av_log(NULL, AV_LOG_ERROR, "%02x", inbuffer[i]);
939//    }
940//    av_log(NULL, AV_LOG_ERROR, "\n");
941
942    decode_bytes_and_gain(q, inbuffer, &q->gains1);
943
944    if (q->joint_stereo) {
945        joint_decode(q, q->decode_buffer_1, q->decode_buffer_2);
946    } else {
947        mono_decode(q, q->decode_buffer_1);
948
949        if (q->nb_channels == 2) {
950            decode_bytes_and_gain(q, inbuffer + sub_packet_size/2, &q->gains2);
951            mono_decode(q, q->decode_buffer_2);
952        }
953    }
954
955    mlt_compensate_output(q, q->decode_buffer_1, &q->gains1,
956                          q->mono_previous_buffer1, outbuffer, 0);
957
958    if (q->nb_channels == 2) {
959        if (q->joint_stereo) {
960            mlt_compensate_output(q, q->decode_buffer_2, &q->gains1,
961                                  q->mono_previous_buffer2, outbuffer, 1);
962        } else {
963            mlt_compensate_output(q, q->decode_buffer_2, &q->gains2,
964                                  q->mono_previous_buffer2, outbuffer, 1);
965        }
966    }
967    return q->samples_per_frame * sizeof(int16_t);
968}
969
970
971/**
972 * Cook frame decoding
973 *
974 * @param avctx     pointer to the AVCodecContext
975 */
976
977static int cook_decode_frame(AVCodecContext *avctx,
978            void *data, int *data_size,
979            const uint8_t *buf, int buf_size) {
980    COOKContext *q = avctx->priv_data;
981
982    if (buf_size < avctx->block_align)
983        return buf_size;
984
985    *data_size = decode_subpacket(q, buf, avctx->block_align, data);
986
987    /* Discard the first two frames: no valid audio. */
988    if (avctx->frame_number < 2) *data_size = 0;
989
990    return avctx->block_align;
991}
992
993#ifdef COOKDEBUG
994static void dump_cook_context(COOKContext *q)
995{
996    //int i=0;
997#define PRINT(a,b) av_log(NULL,AV_LOG_ERROR," %s = %d\n", a, b);
998    av_log(NULL,AV_LOG_ERROR,"COOKextradata\n");
999    av_log(NULL,AV_LOG_ERROR,"cookversion=%x\n",q->cookversion);
1000    if (q->cookversion > STEREO) {
1001        PRINT("js_subband_start",q->js_subband_start);
1002        PRINT("js_vlc_bits",q->js_vlc_bits);
1003    }
1004    av_log(NULL,AV_LOG_ERROR,"COOKContext\n");
1005    PRINT("nb_channels",q->nb_channels);
1006    PRINT("bit_rate",q->bit_rate);
1007    PRINT("sample_rate",q->sample_rate);
1008    PRINT("samples_per_channel",q->samples_per_channel);
1009    PRINT("samples_per_frame",q->samples_per_frame);
1010    PRINT("subbands",q->subbands);
1011    PRINT("random_state",q->random_state);
1012    PRINT("js_subband_start",q->js_subband_start);
1013    PRINT("log2_numvector_size",q->log2_numvector_size);
1014    PRINT("numvector_size",q->numvector_size);
1015    PRINT("total_subbands",q->total_subbands);
1016}
1017#endif
1018
1019/**
1020 * Cook initialization
1021 *
1022 * @param avctx     pointer to the AVCodecContext
1023 */
1024
1025static av_cold int cook_decode_init(AVCodecContext *avctx)
1026{
1027    COOKContext *q = avctx->priv_data;
1028    const uint8_t *edata_ptr = avctx->extradata;
1029
1030    /* Take care of the codec specific extradata. */
1031    if (avctx->extradata_size <= 0) {
1032        av_log(avctx,AV_LOG_ERROR,"Necessary extradata missing!\n");
1033        return -1;
1034    } else {
1035        /* 8 for mono, 16 for stereo, ? for multichannel
1036           Swap to right endianness so we don't need to care later on. */
1037        av_log(avctx,AV_LOG_DEBUG,"codecdata_length=%d\n",avctx->extradata_size);
1038        if (avctx->extradata_size >= 8){
1039            q->cookversion = bytestream_get_be32(&edata_ptr);
1040            q->samples_per_frame =  bytestream_get_be16(&edata_ptr);
1041            q->subbands = bytestream_get_be16(&edata_ptr);
1042        }
1043        if (avctx->extradata_size >= 16){
1044            bytestream_get_be32(&edata_ptr);    //Unknown unused
1045            q->js_subband_start = bytestream_get_be16(&edata_ptr);
1046            q->js_vlc_bits = bytestream_get_be16(&edata_ptr);
1047        }
1048    }
1049
1050    /* Take data from the AVCodecContext (RM container). */
1051    q->sample_rate = avctx->sample_rate;
1052    q->nb_channels = avctx->channels;
1053    q->bit_rate = avctx->bit_rate;
1054
1055    /* Initialize RNG. */
1056    av_random_init(&q->random_state, 1);
1057
1058    /* Initialize extradata related variables. */
1059    q->samples_per_channel = q->samples_per_frame / q->nb_channels;
1060    q->bits_per_subpacket = avctx->block_align * 8;
1061
1062    /* Initialize default data states. */
1063    q->log2_numvector_size = 5;
1064    q->total_subbands = q->subbands;
1065
1066    /* Initialize version-dependent variables */
1067    av_log(NULL,AV_LOG_DEBUG,"q->cookversion=%x\n",q->cookversion);
1068    q->joint_stereo = 0;
1069    switch (q->cookversion) {
1070        case MONO:
1071            if (q->nb_channels != 1) {
1072                av_log(avctx,AV_LOG_ERROR,"Container channels != 1, report sample!\n");
1073                return -1;
1074            }
1075            av_log(avctx,AV_LOG_DEBUG,"MONO\n");
1076            break;
1077        case STEREO:
1078            if (q->nb_channels != 1) {
1079                q->bits_per_subpacket = q->bits_per_subpacket/2;
1080            }
1081            av_log(avctx,AV_LOG_DEBUG,"STEREO\n");
1082            break;
1083        case JOINT_STEREO:
1084            if (q->nb_channels != 2) {
1085                av_log(avctx,AV_LOG_ERROR,"Container channels != 2, report sample!\n");
1086                return -1;
1087            }
1088            av_log(avctx,AV_LOG_DEBUG,"JOINT_STEREO\n");
1089            if (avctx->extradata_size >= 16){
1090                q->total_subbands = q->subbands + q->js_subband_start;
1091                q->joint_stereo = 1;
1092            }
1093            if (q->samples_per_channel > 256) {
1094                q->log2_numvector_size  = 6;
1095            }
1096            if (q->samples_per_channel > 512) {
1097                q->log2_numvector_size  = 7;
1098            }
1099            break;
1100        case MC_COOK:
1101            av_log(avctx,AV_LOG_ERROR,"MC_COOK not supported!\n");
1102            return -1;
1103            break;
1104        default:
1105            av_log(avctx,AV_LOG_ERROR,"Unknown Cook version, report sample!\n");
1106            return -1;
1107            break;
1108    }
1109
1110    /* Initialize variable relations */
1111    q->numvector_size = (1 << q->log2_numvector_size);
1112
1113    /* Generate tables */
1114    init_pow2table();
1115    init_gain_table(q);
1116    init_cplscales_table(q);
1117
1118    if (init_cook_vlc_tables(q) != 0)
1119        return -1;
1120
1121
1122    if(avctx->block_align >= UINT_MAX/2)
1123        return -1;
1124
1125    /* Pad the databuffer with:
1126       DECODE_BYTES_PAD1 or DECODE_BYTES_PAD2 for decode_bytes(),
1127       FF_INPUT_BUFFER_PADDING_SIZE, for the bitstreamreader. */
1128    if (q->nb_channels==2 && q->joint_stereo==0) {
1129        q->decoded_bytes_buffer =
1130          av_mallocz(avctx->block_align/2
1131                     + DECODE_BYTES_PAD2(avctx->block_align/2)
1132                     + FF_INPUT_BUFFER_PADDING_SIZE);
1133    } else {
1134        q->decoded_bytes_buffer =
1135          av_mallocz(avctx->block_align
1136                     + DECODE_BYTES_PAD1(avctx->block_align)
1137                     + FF_INPUT_BUFFER_PADDING_SIZE);
1138    }
1139    if (q->decoded_bytes_buffer == NULL)
1140        return -1;
1141
1142    q->gains1.now      = q->gain_1;
1143    q->gains1.previous = q->gain_2;
1144    q->gains2.now      = q->gain_3;
1145    q->gains2.previous = q->gain_4;
1146
1147    /* Initialize transform. */
1148    if ( init_cook_mlt(q) != 0 )
1149        return -1;
1150
1151    /* Initialize COOK signal arithmetic handling */
1152    if (1) {
1153        q->scalar_dequant  = scalar_dequant_float;
1154        q->decouple        = decouple_float;
1155        q->imlt_window     = imlt_window_float;
1156        q->interpolate     = interpolate_float;
1157        q->saturate_output = saturate_output_float;
1158    }
1159
1160    /* Try to catch some obviously faulty streams, othervise it might be exploitable */
1161    if (q->total_subbands > 53) {
1162        av_log(avctx,AV_LOG_ERROR,"total_subbands > 53, report sample!\n");
1163        return -1;
1164    }
1165    if (q->subbands > 50) {
1166        av_log(avctx,AV_LOG_ERROR,"subbands > 50, report sample!\n");
1167        return -1;
1168    }
1169    if ((q->samples_per_channel == 256) || (q->samples_per_channel == 512) || (q->samples_per_channel == 1024)) {
1170    } else {
1171        av_log(avctx,AV_LOG_ERROR,"unknown amount of samples_per_channel = %d, report sample!\n",q->samples_per_channel);
1172        return -1;
1173    }
1174    if ((q->js_vlc_bits > 6) || (q->js_vlc_bits < 0)) {
1175        av_log(avctx,AV_LOG_ERROR,"q->js_vlc_bits = %d, only >= 0 and <= 6 allowed!\n",q->js_vlc_bits);
1176        return -1;
1177    }
1178
1179    avctx->sample_fmt = SAMPLE_FMT_S16;
1180    avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
1181
1182#ifdef COOKDEBUG
1183    dump_cook_context(q);
1184#endif
1185    return 0;
1186}
1187
1188
1189AVCodec cook_decoder =
1190{
1191    .name = "cook",
1192    .type = CODEC_TYPE_AUDIO,
1193    .id = CODEC_ID_COOK,
1194    .priv_data_size = sizeof(COOKContext),
1195    .init = cook_decode_init,
1196    .close = cook_decode_close,
1197    .decode = cook_decode_frame,
1198    .long_name = NULL_IF_CONFIG_SMALL("COOK"),
1199};
1200