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libavcodec/adpcm.c

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00001 /*
00002  * Copyright (c) 2001-2003 The ffmpeg Project
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 #include "avcodec.h"
00021 #include "get_bits.h"
00022 #include "put_bits.h"
00023 #include "bytestream.h"
00024 #include "adpcm.h"
00025 #include "adpcm_data.h"
00026 
00059 /* These are for CD-ROM XA ADPCM */
00060 static const int xa_adpcm_table[5][2] = {
00061     {   0,   0 },
00062     {  60,   0 },
00063     { 115, -52 },
00064     {  98, -55 },
00065     { 122, -60 }
00066 };
00067 
00068 static const int ea_adpcm_table[] = {
00069     0,  240,  460,  392,
00070     0,    0, -208, -220,
00071     0,    1,    3,    4,
00072     7,    8,   10,   11,
00073     0,   -1,   -3,   -4
00074 };
00075 
00076 // padded to zero where table size is less then 16
00077 static const int swf_index_tables[4][16] = {
00078     /*2*/ { -1, 2 },
00079     /*3*/ { -1, -1, 2, 4 },
00080     /*4*/ { -1, -1, -1, -1, 2, 4, 6, 8 },
00081     /*5*/ { -1, -1, -1, -1, -1, -1, -1, -1, 1, 2, 4, 6, 8, 10, 13, 16 }
00082 };
00083 
00084 /* end of tables */
00085 
00086 typedef struct ADPCMDecodeContext {
00087     AVFrame frame;
00088     ADPCMChannelStatus status[6];
00089     int vqa_version;                
00090 } ADPCMDecodeContext;
00091 
00092 static av_cold int adpcm_decode_init(AVCodecContext * avctx)
00093 {
00094     ADPCMDecodeContext *c = avctx->priv_data;
00095     unsigned int min_channels = 1;
00096     unsigned int max_channels = 2;
00097 
00098     switch(avctx->codec->id) {
00099     case CODEC_ID_ADPCM_EA:
00100         min_channels = 2;
00101         break;
00102     case CODEC_ID_ADPCM_EA_R1:
00103     case CODEC_ID_ADPCM_EA_R2:
00104     case CODEC_ID_ADPCM_EA_R3:
00105     case CODEC_ID_ADPCM_EA_XAS:
00106         max_channels = 6;
00107         break;
00108     }
00109     if (avctx->channels < min_channels || avctx->channels > max_channels) {
00110         av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
00111         return AVERROR(EINVAL);
00112     }
00113 
00114     switch(avctx->codec->id) {
00115     case CODEC_ID_ADPCM_CT:
00116         c->status[0].step = c->status[1].step = 511;
00117         break;
00118     case CODEC_ID_ADPCM_IMA_WAV:
00119         if (avctx->bits_per_coded_sample != 4) {
00120             av_log(avctx, AV_LOG_ERROR, "Only 4-bit ADPCM IMA WAV files are supported\n");
00121             return -1;
00122         }
00123         break;
00124     case CODEC_ID_ADPCM_IMA_APC:
00125         if (avctx->extradata && avctx->extradata_size >= 8) {
00126             c->status[0].predictor = AV_RL32(avctx->extradata);
00127             c->status[1].predictor = AV_RL32(avctx->extradata + 4);
00128         }
00129         break;
00130     case CODEC_ID_ADPCM_IMA_WS:
00131         if (avctx->extradata && avctx->extradata_size >= 42)
00132             c->vqa_version = AV_RL16(avctx->extradata);
00133         break;
00134     default:
00135         break;
00136     }
00137     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00138 
00139     avcodec_get_frame_defaults(&c->frame);
00140     avctx->coded_frame = &c->frame;
00141 
00142     return 0;
00143 }
00144 
00145 static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift)
00146 {
00147     int step_index;
00148     int predictor;
00149     int sign, delta, diff, step;
00150 
00151     step = ff_adpcm_step_table[c->step_index];
00152     step_index = c->step_index + ff_adpcm_index_table[(unsigned)nibble];
00153     if (step_index < 0) step_index = 0;
00154     else if (step_index > 88) step_index = 88;
00155 
00156     sign = nibble & 8;
00157     delta = nibble & 7;
00158     /* perform direct multiplication instead of series of jumps proposed by
00159      * the reference ADPCM implementation since modern CPUs can do the mults
00160      * quickly enough */
00161     diff = ((2 * delta + 1) * step) >> shift;
00162     predictor = c->predictor;
00163     if (sign) predictor -= diff;
00164     else predictor += diff;
00165 
00166     c->predictor = av_clip_int16(predictor);
00167     c->step_index = step_index;
00168 
00169     return (short)c->predictor;
00170 }
00171 
00172 static inline int adpcm_ima_qt_expand_nibble(ADPCMChannelStatus *c, int nibble, int shift)
00173 {
00174     int step_index;
00175     int predictor;
00176     int diff, step;
00177 
00178     step = ff_adpcm_step_table[c->step_index];
00179     step_index = c->step_index + ff_adpcm_index_table[nibble];
00180     step_index = av_clip(step_index, 0, 88);
00181 
00182     diff = step >> 3;
00183     if (nibble & 4) diff += step;
00184     if (nibble & 2) diff += step >> 1;
00185     if (nibble & 1) diff += step >> 2;
00186 
00187     if (nibble & 8)
00188         predictor = c->predictor - diff;
00189     else
00190         predictor = c->predictor + diff;
00191 
00192     c->predictor = av_clip_int16(predictor);
00193     c->step_index = step_index;
00194 
00195     return c->predictor;
00196 }
00197 
00198 static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
00199 {
00200     int predictor;
00201 
00202     predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 64;
00203     predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
00204 
00205     c->sample2 = c->sample1;
00206     c->sample1 = av_clip_int16(predictor);
00207     c->idelta = (ff_adpcm_AdaptationTable[(int)nibble] * c->idelta) >> 8;
00208     if (c->idelta < 16) c->idelta = 16;
00209 
00210     return c->sample1;
00211 }
00212 
00213 static inline short adpcm_ct_expand_nibble(ADPCMChannelStatus *c, char nibble)
00214 {
00215     int sign, delta, diff;
00216     int new_step;
00217 
00218     sign = nibble & 8;
00219     delta = nibble & 7;
00220     /* perform direct multiplication instead of series of jumps proposed by
00221      * the reference ADPCM implementation since modern CPUs can do the mults
00222      * quickly enough */
00223     diff = ((2 * delta + 1) * c->step) >> 3;
00224     /* predictor update is not so trivial: predictor is multiplied on 254/256 before updating */
00225     c->predictor = ((c->predictor * 254) >> 8) + (sign ? -diff : diff);
00226     c->predictor = av_clip_int16(c->predictor);
00227     /* calculate new step and clamp it to range 511..32767 */
00228     new_step = (ff_adpcm_AdaptationTable[nibble & 7] * c->step) >> 8;
00229     c->step = av_clip(new_step, 511, 32767);
00230 
00231     return (short)c->predictor;
00232 }
00233 
00234 static inline short adpcm_sbpro_expand_nibble(ADPCMChannelStatus *c, char nibble, int size, int shift)
00235 {
00236     int sign, delta, diff;
00237 
00238     sign = nibble & (1<<(size-1));
00239     delta = nibble & ((1<<(size-1))-1);
00240     diff = delta << (7 + c->step + shift);
00241 
00242     /* clamp result */
00243     c->predictor = av_clip(c->predictor + (sign ? -diff : diff), -16384,16256);
00244 
00245     /* calculate new step */
00246     if (delta >= (2*size - 3) && c->step < 3)
00247         c->step++;
00248     else if (delta == 0 && c->step > 0)
00249         c->step--;
00250 
00251     return (short) c->predictor;
00252 }
00253 
00254 static inline short adpcm_yamaha_expand_nibble(ADPCMChannelStatus *c, unsigned char nibble)
00255 {
00256     if(!c->step) {
00257         c->predictor = 0;
00258         c->step = 127;
00259     }
00260 
00261     c->predictor += (c->step * ff_adpcm_yamaha_difflookup[nibble]) / 8;
00262     c->predictor = av_clip_int16(c->predictor);
00263     c->step = (c->step * ff_adpcm_yamaha_indexscale[nibble]) >> 8;
00264     c->step = av_clip(c->step, 127, 24567);
00265     return c->predictor;
00266 }
00267 
00268 static int xa_decode(AVCodecContext *avctx,
00269                      short *out, const unsigned char *in,
00270                      ADPCMChannelStatus *left, ADPCMChannelStatus *right, int inc)
00271 {
00272     int i, j;
00273     int shift,filter,f0,f1;
00274     int s_1,s_2;
00275     int d,s,t;
00276 
00277     for(i=0;i<4;i++) {
00278 
00279         shift  = 12 - (in[4+i*2] & 15);
00280         filter = in[4+i*2] >> 4;
00281         if (filter > 4) {
00282             av_log(avctx, AV_LOG_ERROR,
00283                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",
00284                    filter);
00285             return AVERROR_INVALIDDATA;
00286         }
00287         f0 = xa_adpcm_table[filter][0];
00288         f1 = xa_adpcm_table[filter][1];
00289 
00290         s_1 = left->sample1;
00291         s_2 = left->sample2;
00292 
00293         for(j=0;j<28;j++) {
00294             d = in[16+i+j*4];
00295 
00296             t = (signed char)(d<<4)>>4;
00297             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
00298             s_2 = s_1;
00299             s_1 = av_clip_int16(s);
00300             *out = s_1;
00301             out += inc;
00302         }
00303 
00304         if (inc==2) { /* stereo */
00305             left->sample1 = s_1;
00306             left->sample2 = s_2;
00307             s_1 = right->sample1;
00308             s_2 = right->sample2;
00309             out = out + 1 - 28*2;
00310         }
00311 
00312         shift  = 12 - (in[5+i*2] & 15);
00313         filter = in[5+i*2] >> 4;
00314         if (filter > 4) {
00315             av_log(avctx, AV_LOG_ERROR,
00316                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",
00317                    filter);
00318             return AVERROR_INVALIDDATA;
00319         }
00320         f0 = xa_adpcm_table[filter][0];
00321         f1 = xa_adpcm_table[filter][1];
00322 
00323         for(j=0;j<28;j++) {
00324             d = in[16+i+j*4];
00325 
00326             t = (signed char)d >> 4;
00327             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
00328             s_2 = s_1;
00329             s_1 = av_clip_int16(s);
00330             *out = s_1;
00331             out += inc;
00332         }
00333 
00334         if (inc==2) { /* stereo */
00335             right->sample1 = s_1;
00336             right->sample2 = s_2;
00337             out -= 1;
00338         } else {
00339             left->sample1 = s_1;
00340             left->sample2 = s_2;
00341         }
00342     }
00343 
00344     return 0;
00345 }
00346 
00356 static int get_nb_samples(AVCodecContext *avctx, const uint8_t *buf,
00357                           int buf_size, int *coded_samples)
00358 {
00359     ADPCMDecodeContext *s = avctx->priv_data;
00360     int nb_samples        = 0;
00361     int ch                = avctx->channels;
00362     int has_coded_samples = 0;
00363     int header_size;
00364 
00365     *coded_samples = 0;
00366 
00367     if(ch <= 0)
00368         return 0;
00369 
00370     switch (avctx->codec->id) {
00371     /* constant, only check buf_size */
00372     case CODEC_ID_ADPCM_EA_XAS:
00373         if (buf_size < 76 * ch)
00374             return 0;
00375         nb_samples = 128;
00376         break;
00377     case CODEC_ID_ADPCM_IMA_QT:
00378         if (buf_size < 34 * ch)
00379             return 0;
00380         nb_samples = 64;
00381         break;
00382     /* simple 4-bit adpcm */
00383     case CODEC_ID_ADPCM_CT:
00384     case CODEC_ID_ADPCM_IMA_APC:
00385     case CODEC_ID_ADPCM_IMA_EA_SEAD:
00386     case CODEC_ID_ADPCM_IMA_WS:
00387     case CODEC_ID_ADPCM_YAMAHA:
00388         nb_samples = buf_size * 2 / ch;
00389         break;
00390     }
00391     if (nb_samples)
00392         return nb_samples;
00393 
00394     /* simple 4-bit adpcm, with header */
00395     header_size = 0;
00396     switch (avctx->codec->id) {
00397         case CODEC_ID_ADPCM_4XM:
00398         case CODEC_ID_ADPCM_IMA_ISS:     header_size = 4 * ch;      break;
00399         case CODEC_ID_ADPCM_IMA_AMV:     header_size = 8;           break;
00400         case CODEC_ID_ADPCM_IMA_SMJPEG:  header_size = 4;           break;
00401     }
00402     if (header_size > 0)
00403         return (buf_size - header_size) * 2 / ch;
00404 
00405     /* more complex formats */
00406     switch (avctx->codec->id) {
00407     case CODEC_ID_ADPCM_EA:
00408         has_coded_samples = 1;
00409         if (buf_size < 4)
00410             return 0;
00411         *coded_samples  = AV_RL32(buf);
00412         *coded_samples -= *coded_samples % 28;
00413         nb_samples      = (buf_size - 12) / 30 * 28;
00414         break;
00415     case CODEC_ID_ADPCM_IMA_EA_EACS:
00416         has_coded_samples = 1;
00417         if (buf_size < 4)
00418             return 0;
00419         *coded_samples = AV_RL32(buf);
00420         nb_samples     = (buf_size - (4 + 8 * ch)) * 2 / ch;
00421         break;
00422     case CODEC_ID_ADPCM_EA_MAXIS_XA:
00423         nb_samples = ((buf_size - ch) / (2 * ch)) * 2 * ch;
00424         break;
00425     case CODEC_ID_ADPCM_EA_R1:
00426     case CODEC_ID_ADPCM_EA_R2:
00427     case CODEC_ID_ADPCM_EA_R3:
00428         /* maximum number of samples */
00429         /* has internal offsets and a per-frame switch to signal raw 16-bit */
00430         has_coded_samples = 1;
00431         if (buf_size < 4)
00432             return 0;
00433         switch (avctx->codec->id) {
00434         case CODEC_ID_ADPCM_EA_R1:
00435             header_size    = 4 + 9 * ch;
00436             *coded_samples = AV_RL32(buf);
00437             break;
00438         case CODEC_ID_ADPCM_EA_R2:
00439             header_size    = 4 + 5 * ch;
00440             *coded_samples = AV_RL32(buf);
00441             break;
00442         case CODEC_ID_ADPCM_EA_R3:
00443             header_size    = 4 + 5 * ch;
00444             *coded_samples = AV_RB32(buf);
00445             break;
00446         }
00447         *coded_samples -= *coded_samples % 28;
00448         nb_samples      = (buf_size - header_size) * 2 / ch;
00449         nb_samples     -= nb_samples % 28;
00450         break;
00451     case CODEC_ID_ADPCM_IMA_DK3:
00452         if (avctx->block_align > 0)
00453             buf_size = FFMIN(buf_size, avctx->block_align);
00454         nb_samples = ((buf_size - 16) * 8 / 3) / ch;
00455         break;
00456     case CODEC_ID_ADPCM_IMA_DK4:
00457         nb_samples = 1 + (buf_size - 4 * ch) * 2 / ch;
00458         break;
00459     case CODEC_ID_ADPCM_IMA_WAV:
00460         if (avctx->block_align > 0)
00461             buf_size = FFMIN(buf_size, avctx->block_align);
00462         nb_samples = 1 + (buf_size - 4 * ch) / (4 * ch) * 8;
00463         break;
00464     case CODEC_ID_ADPCM_MS:
00465         if (avctx->block_align > 0)
00466             buf_size = FFMIN(buf_size, avctx->block_align);
00467         nb_samples = 2 + (buf_size - 7 * ch) * 2 / ch;
00468         break;
00469     case CODEC_ID_ADPCM_SBPRO_2:
00470     case CODEC_ID_ADPCM_SBPRO_3:
00471     case CODEC_ID_ADPCM_SBPRO_4:
00472     {
00473         int samples_per_byte;
00474         switch (avctx->codec->id) {
00475         case CODEC_ID_ADPCM_SBPRO_2: samples_per_byte = 4; break;
00476         case CODEC_ID_ADPCM_SBPRO_3: samples_per_byte = 3; break;
00477         case CODEC_ID_ADPCM_SBPRO_4: samples_per_byte = 2; break;
00478         }
00479         if (!s->status[0].step_index) {
00480             nb_samples++;
00481             buf_size -= ch;
00482         }
00483         nb_samples += buf_size * samples_per_byte / ch;
00484         break;
00485     }
00486     case CODEC_ID_ADPCM_SWF:
00487     {
00488         int buf_bits       = buf_size * 8 - 2;
00489         int nbits          = (buf[0] >> 6) + 2;
00490         int block_hdr_size = 22 * ch;
00491         int block_size     = block_hdr_size + nbits * ch * 4095;
00492         int nblocks        = buf_bits / block_size;
00493         int bits_left      = buf_bits - nblocks * block_size;
00494         nb_samples         = nblocks * 4096;
00495         if (bits_left >= block_hdr_size)
00496             nb_samples += 1 + (bits_left - block_hdr_size) / (nbits * ch);
00497         break;
00498     }
00499     case CODEC_ID_ADPCM_THP:
00500         has_coded_samples = 1;
00501         if (buf_size < 8)
00502             return 0;
00503         *coded_samples  = AV_RB32(&buf[4]);
00504         *coded_samples -= *coded_samples % 14;
00505         nb_samples      = (buf_size - 80) / (8 * ch) * 14;
00506         break;
00507     case CODEC_ID_ADPCM_XA:
00508         nb_samples = (buf_size / 128) * 224 / ch;
00509         break;
00510     }
00511 
00512     /* validate coded sample count */
00513     if (has_coded_samples && (*coded_samples <= 0 || *coded_samples > nb_samples))
00514         return AVERROR_INVALIDDATA;
00515 
00516     return nb_samples;
00517 }
00518 
00519 /* DK3 ADPCM support macro */
00520 #define DK3_GET_NEXT_NIBBLE() \
00521     if (decode_top_nibble_next) \
00522     { \
00523         nibble = last_byte >> 4; \
00524         decode_top_nibble_next = 0; \
00525     } \
00526     else \
00527     { \
00528         if (end_of_packet) \
00529             break; \
00530         last_byte = *src++; \
00531         if (src >= buf + buf_size) \
00532             end_of_packet = 1; \
00533         nibble = last_byte & 0x0F; \
00534         decode_top_nibble_next = 1; \
00535     }
00536 
00537 static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
00538                               int *got_frame_ptr, AVPacket *avpkt)
00539 {
00540     const uint8_t *buf = avpkt->data;
00541     int buf_size = avpkt->size;
00542     ADPCMDecodeContext *c = avctx->priv_data;
00543     ADPCMChannelStatus *cs;
00544     int n, m, channel, i;
00545     short *samples;
00546     const uint8_t *src;
00547     int st; /* stereo */
00548     int count1, count2;
00549     int nb_samples, coded_samples, ret;
00550 
00551     nb_samples = get_nb_samples(avctx, buf, buf_size, &coded_samples);
00552     if (nb_samples <= 0) {
00553         av_log(avctx, AV_LOG_ERROR, "invalid number of samples in packet\n");
00554         return AVERROR_INVALIDDATA;
00555     }
00556 
00557     /* get output buffer */
00558     c->frame.nb_samples = nb_samples;
00559     if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) {
00560         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00561         return ret;
00562     }
00563     samples = (short *)c->frame.data[0];
00564 
00565     /* use coded_samples when applicable */
00566     /* it is always <= nb_samples, so the output buffer will be large enough */
00567     if (coded_samples) {
00568         if (coded_samples != nb_samples)
00569             av_log(avctx, AV_LOG_WARNING, "mismatch in coded sample count\n");
00570         c->frame.nb_samples = nb_samples = coded_samples;
00571     }
00572 
00573     src = buf;
00574 
00575     st = avctx->channels == 2 ? 1 : 0;
00576 
00577     switch(avctx->codec->id) {
00578     case CODEC_ID_ADPCM_IMA_QT:
00579         /* In QuickTime, IMA is encoded by chunks of 34 bytes (=64 samples).
00580            Channel data is interleaved per-chunk. */
00581         for (channel = 0; channel < avctx->channels; channel++) {
00582             int16_t predictor;
00583             int step_index;
00584             cs = &(c->status[channel]);
00585             /* (pppppp) (piiiiiii) */
00586 
00587             /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
00588             predictor = AV_RB16(src);
00589             step_index = predictor & 0x7F;
00590             predictor &= 0xFF80;
00591 
00592             src += 2;
00593 
00594             if (cs->step_index == step_index) {
00595                 int diff = (int)predictor - cs->predictor;
00596                 if (diff < 0)
00597                     diff = - diff;
00598                 if (diff > 0x7f)
00599                     goto update;
00600             } else {
00601             update:
00602                 cs->step_index = step_index;
00603                 cs->predictor = predictor;
00604             }
00605 
00606             if (cs->step_index > 88){
00607                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
00608                 cs->step_index = 88;
00609             }
00610 
00611             samples = (short *)c->frame.data[0] + channel;
00612 
00613             for (m = 0; m < 32; m++) {
00614                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] & 0x0F, 3);
00615                 samples += avctx->channels;
00616                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] >> 4  , 3);
00617                 samples += avctx->channels;
00618                 src ++;
00619             }
00620         }
00621         break;
00622     case CODEC_ID_ADPCM_IMA_WAV:
00623         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00624             buf_size = avctx->block_align;
00625 
00626         for(i=0; i<avctx->channels; i++){
00627             cs = &(c->status[i]);
00628             cs->predictor = *samples++ = (int16_t)bytestream_get_le16(&src);
00629 
00630             cs->step_index = *src++;
00631             if (cs->step_index > 88){
00632                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
00633                 cs->step_index = 88;
00634             }
00635             if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null but is %d!!\n", src[-1]); /* unused */
00636         }
00637 
00638         for (n = (nb_samples - 1) / 8; n > 0; n--) {
00639             for (i = 0; i < avctx->channels; i++) {
00640                 cs = &c->status[i];
00641                 for (m = 0; m < 4; m++) {
00642                     uint8_t v = *src++;
00643                     *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 3);
00644                     samples += avctx->channels;
00645                     *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 3);
00646                     samples += avctx->channels;
00647                 }
00648                 samples -= 8 * avctx->channels - 1;
00649             }
00650             samples += 7 * avctx->channels;
00651         }
00652         break;
00653     case CODEC_ID_ADPCM_4XM:
00654         for (i = 0; i < avctx->channels; i++)
00655             c->status[i].predictor= (int16_t)bytestream_get_le16(&src);
00656 
00657         for (i = 0; i < avctx->channels; i++) {
00658             c->status[i].step_index= (int16_t)bytestream_get_le16(&src);
00659             c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);
00660         }
00661 
00662         for (i = 0; i < avctx->channels; i++) {
00663             samples = (short *)c->frame.data[0] + i;
00664             cs = &c->status[i];
00665             for (n = nb_samples >> 1; n > 0; n--, src++) {
00666                 uint8_t v = *src;
00667                 *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 4);
00668                 samples += avctx->channels;
00669                 *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 4);
00670                 samples += avctx->channels;
00671             }
00672         }
00673         break;
00674     case CODEC_ID_ADPCM_MS:
00675     {
00676         int block_predictor;
00677 
00678         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00679             buf_size = avctx->block_align;
00680 
00681         block_predictor = av_clip(*src++, 0, 6);
00682         c->status[0].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];
00683         c->status[0].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];
00684         if (st) {
00685             block_predictor = av_clip(*src++, 0, 6);
00686             c->status[1].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];
00687             c->status[1].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];
00688         }
00689         c->status[0].idelta = (int16_t)bytestream_get_le16(&src);
00690         if (st){
00691             c->status[1].idelta = (int16_t)bytestream_get_le16(&src);
00692         }
00693 
00694         c->status[0].sample1 = bytestream_get_le16(&src);
00695         if (st) c->status[1].sample1 = bytestream_get_le16(&src);
00696         c->status[0].sample2 = bytestream_get_le16(&src);
00697         if (st) c->status[1].sample2 = bytestream_get_le16(&src);
00698 
00699         *samples++ = c->status[0].sample2;
00700         if (st) *samples++ = c->status[1].sample2;
00701         *samples++ = c->status[0].sample1;
00702         if (st) *samples++ = c->status[1].sample1;
00703         for(n = (nb_samples - 2) >> (1 - st); n > 0; n--, src++) {
00704             *samples++ = adpcm_ms_expand_nibble(&c->status[0 ], src[0] >> 4  );
00705             *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
00706         }
00707         break;
00708     }
00709     case CODEC_ID_ADPCM_IMA_DK4:
00710         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00711             buf_size = avctx->block_align;
00712 
00713         for (channel = 0; channel < avctx->channels; channel++) {
00714             cs = &c->status[channel];
00715             cs->predictor  = (int16_t)bytestream_get_le16(&src);
00716             cs->step_index = av_clip(*src++, 0, 88);
00717             src++;
00718             *samples++ = cs->predictor;
00719         }
00720         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00721             uint8_t v = *src;
00722             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v >> 4  , 3);
00723             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);
00724         }
00725         break;
00726     case CODEC_ID_ADPCM_IMA_DK3:
00727     {
00728         unsigned char last_byte = 0;
00729         unsigned char nibble;
00730         int decode_top_nibble_next = 0;
00731         int end_of_packet = 0;
00732         int diff_channel;
00733 
00734         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00735             buf_size = avctx->block_align;
00736 
00737         c->status[0].predictor  = (int16_t)AV_RL16(src + 10);
00738         c->status[1].predictor  = (int16_t)AV_RL16(src + 12);
00739         c->status[0].step_index = av_clip(src[14], 0, 88);
00740         c->status[1].step_index = av_clip(src[15], 0, 88);
00741         /* sign extend the predictors */
00742         src += 16;
00743         diff_channel = c->status[1].predictor;
00744 
00745         /* the DK3_GET_NEXT_NIBBLE macro issues the break statement when
00746          * the buffer is consumed */
00747         while (1) {
00748 
00749             /* for this algorithm, c->status[0] is the sum channel and
00750              * c->status[1] is the diff channel */
00751 
00752             /* process the first predictor of the sum channel */
00753             DK3_GET_NEXT_NIBBLE();
00754             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
00755 
00756             /* process the diff channel predictor */
00757             DK3_GET_NEXT_NIBBLE();
00758             adpcm_ima_expand_nibble(&c->status[1], nibble, 3);
00759 
00760             /* process the first pair of stereo PCM samples */
00761             diff_channel = (diff_channel + c->status[1].predictor) / 2;
00762             *samples++ = c->status[0].predictor + c->status[1].predictor;
00763             *samples++ = c->status[0].predictor - c->status[1].predictor;
00764 
00765             /* process the second predictor of the sum channel */
00766             DK3_GET_NEXT_NIBBLE();
00767             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
00768 
00769             /* process the second pair of stereo PCM samples */
00770             diff_channel = (diff_channel + c->status[1].predictor) / 2;
00771             *samples++ = c->status[0].predictor + c->status[1].predictor;
00772             *samples++ = c->status[0].predictor - c->status[1].predictor;
00773         }
00774         break;
00775     }
00776     case CODEC_ID_ADPCM_IMA_ISS:
00777         for (channel = 0; channel < avctx->channels; channel++) {
00778             cs = &c->status[channel];
00779             cs->predictor  = (int16_t)bytestream_get_le16(&src);
00780             cs->step_index = av_clip(*src++, 0, 88);
00781             src++;
00782         }
00783 
00784         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00785             uint8_t v1, v2;
00786             uint8_t v = *src;
00787             /* nibbles are swapped for mono */
00788             if (st) {
00789                 v1 = v >> 4;
00790                 v2 = v & 0x0F;
00791             } else {
00792                 v2 = v >> 4;
00793                 v1 = v & 0x0F;
00794             }
00795             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v1, 3);
00796             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v2, 3);
00797         }
00798         break;
00799     case CODEC_ID_ADPCM_IMA_APC:
00800         while (src < buf + buf_size) {
00801             uint8_t v = *src++;
00802             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  v >> 4  , 3);
00803             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);
00804         }
00805         break;
00806     case CODEC_ID_ADPCM_IMA_WS:
00807         for (channel = 0; channel < avctx->channels; channel++) {
00808             const uint8_t *src0;
00809             int src_stride;
00810             int16_t *smp = samples + channel;
00811 
00812             if (c->vqa_version == 3) {
00813                 src0 = src + channel * buf_size / 2;
00814                 src_stride = 1;
00815             } else {
00816                 src0 = src + channel;
00817                 src_stride = avctx->channels;
00818             }
00819             for (n = nb_samples / 2; n > 0; n--) {
00820                 uint8_t v = *src0;
00821                 src0 += src_stride;
00822                 *smp = adpcm_ima_expand_nibble(&c->status[channel], v >> 4  , 3);
00823                 smp += avctx->channels;
00824                 *smp = adpcm_ima_expand_nibble(&c->status[channel], v & 0x0F, 3);
00825                 smp += avctx->channels;
00826             }
00827         }
00828         src = buf + buf_size;
00829         break;
00830     case CODEC_ID_ADPCM_XA:
00831         while (buf_size >= 128) {
00832             if ((ret = xa_decode(avctx, samples, src, &c->status[0],
00833                                  &c->status[1], avctx->channels)) < 0)
00834                 return ret;
00835             src += 128;
00836             samples += 28 * 8;
00837             buf_size -= 128;
00838         }
00839         break;
00840     case CODEC_ID_ADPCM_IMA_EA_EACS:
00841         src += 4; // skip sample count (already read)
00842 
00843         for (i=0; i<=st; i++)
00844             c->status[i].step_index = av_clip(bytestream_get_le32(&src), 0, 88);
00845         for (i=0; i<=st; i++)
00846             c->status[i].predictor  = bytestream_get_le32(&src);
00847 
00848         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00849             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  *src>>4,   3);
00850             *samples++ = adpcm_ima_expand_nibble(&c->status[st], *src&0x0F, 3);
00851         }
00852         break;
00853     case CODEC_ID_ADPCM_IMA_EA_SEAD:
00854         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00855             *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] >> 4, 6);
00856             *samples++ = adpcm_ima_expand_nibble(&c->status[st],src[0]&0x0F, 6);
00857         }
00858         break;
00859     case CODEC_ID_ADPCM_EA:
00860     {
00861         int32_t previous_left_sample, previous_right_sample;
00862         int32_t current_left_sample, current_right_sample;
00863         int32_t next_left_sample, next_right_sample;
00864         int32_t coeff1l, coeff2l, coeff1r, coeff2r;
00865         uint8_t shift_left, shift_right;
00866 
00867         /* Each EA ADPCM frame has a 12-byte header followed by 30-byte pieces,
00868            each coding 28 stereo samples. */
00869 
00870         if(avctx->channels != 2)
00871             return AVERROR_INVALIDDATA;
00872 
00873         src += 4; // skip sample count (already read)
00874 
00875         current_left_sample   = (int16_t)bytestream_get_le16(&src);
00876         previous_left_sample  = (int16_t)bytestream_get_le16(&src);
00877         current_right_sample  = (int16_t)bytestream_get_le16(&src);
00878         previous_right_sample = (int16_t)bytestream_get_le16(&src);
00879 
00880         for (count1 = 0; count1 < nb_samples / 28; count1++) {
00881             coeff1l = ea_adpcm_table[ *src >> 4       ];
00882             coeff2l = ea_adpcm_table[(*src >> 4  ) + 4];
00883             coeff1r = ea_adpcm_table[*src & 0x0F];
00884             coeff2r = ea_adpcm_table[(*src & 0x0F) + 4];
00885             src++;
00886 
00887             shift_left  = 20 - (*src >> 4);
00888             shift_right = 20 - (*src & 0x0F);
00889             src++;
00890 
00891             for (count2 = 0; count2 < 28; count2++) {
00892                 next_left_sample  = sign_extend(*src >> 4, 4) << shift_left;
00893                 next_right_sample = sign_extend(*src,      4) << shift_right;
00894                 src++;
00895 
00896                 next_left_sample = (next_left_sample +
00897                     (current_left_sample * coeff1l) +
00898                     (previous_left_sample * coeff2l) + 0x80) >> 8;
00899                 next_right_sample = (next_right_sample +
00900                     (current_right_sample * coeff1r) +
00901                     (previous_right_sample * coeff2r) + 0x80) >> 8;
00902 
00903                 previous_left_sample = current_left_sample;
00904                 current_left_sample = av_clip_int16(next_left_sample);
00905                 previous_right_sample = current_right_sample;
00906                 current_right_sample = av_clip_int16(next_right_sample);
00907                 *samples++ = (unsigned short)current_left_sample;
00908                 *samples++ = (unsigned short)current_right_sample;
00909             }
00910         }
00911 
00912         if (src - buf == buf_size - 2)
00913             src += 2; // Skip terminating 0x0000
00914 
00915         break;
00916     }
00917     case CODEC_ID_ADPCM_EA_MAXIS_XA:
00918     {
00919         int coeff[2][2], shift[2];
00920 
00921         for(channel = 0; channel < avctx->channels; channel++) {
00922             for (i=0; i<2; i++)
00923                 coeff[channel][i] = ea_adpcm_table[(*src >> 4) + 4*i];
00924             shift[channel] = 20 - (*src & 0x0F);
00925             src++;
00926         }
00927         for (count1 = 0; count1 < nb_samples / 2; count1++) {
00928             for(i = 4; i >= 0; i-=4) { /* Pairwise samples LL RR (st) or LL LL (mono) */
00929                 for(channel = 0; channel < avctx->channels; channel++) {
00930                     int32_t sample = sign_extend(src[channel] >> i, 4) << shift[channel];
00931                     sample = (sample +
00932                              c->status[channel].sample1 * coeff[channel][0] +
00933                              c->status[channel].sample2 * coeff[channel][1] + 0x80) >> 8;
00934                     c->status[channel].sample2 = c->status[channel].sample1;
00935                     c->status[channel].sample1 = av_clip_int16(sample);
00936                     *samples++ = c->status[channel].sample1;
00937                 }
00938             }
00939             src+=avctx->channels;
00940         }
00941         /* consume whole packet */
00942         src = buf + buf_size;
00943         break;
00944     }
00945     case CODEC_ID_ADPCM_EA_R1:
00946     case CODEC_ID_ADPCM_EA_R2:
00947     case CODEC_ID_ADPCM_EA_R3: {
00948         /* channel numbering
00949            2chan: 0=fl, 1=fr
00950            4chan: 0=fl, 1=rl, 2=fr, 3=rr
00951            6chan: 0=fl, 1=c,  2=fr, 3=rl,  4=rr, 5=sub */
00952         const int big_endian = avctx->codec->id == CODEC_ID_ADPCM_EA_R3;
00953         int32_t previous_sample, current_sample, next_sample;
00954         int32_t coeff1, coeff2;
00955         uint8_t shift;
00956         unsigned int channel;
00957         uint16_t *samplesC;
00958         const uint8_t *srcC;
00959         const uint8_t *src_end = buf + buf_size;
00960         int count = 0;
00961 
00962         src += 4; // skip sample count (already read)
00963 
00964         for (channel=0; channel<avctx->channels; channel++) {
00965             int32_t offset = (big_endian ? bytestream_get_be32(&src)
00966                                          : bytestream_get_le32(&src))
00967                            + (avctx->channels-channel-1) * 4;
00968 
00969             if ((offset < 0) || (offset >= src_end - src - 4)) break;
00970             srcC  = src + offset;
00971             samplesC = samples + channel;
00972 
00973             if (avctx->codec->id == CODEC_ID_ADPCM_EA_R1) {
00974                 current_sample  = (int16_t)bytestream_get_le16(&srcC);
00975                 previous_sample = (int16_t)bytestream_get_le16(&srcC);
00976             } else {
00977                 current_sample  = c->status[channel].predictor;
00978                 previous_sample = c->status[channel].prev_sample;
00979             }
00980 
00981             for (count1 = 0; count1 < nb_samples / 28; count1++) {
00982                 if (*srcC == 0xEE) {  /* only seen in R2 and R3 */
00983                     srcC++;
00984                     if (srcC > src_end - 30*2) break;
00985                     current_sample  = (int16_t)bytestream_get_be16(&srcC);
00986                     previous_sample = (int16_t)bytestream_get_be16(&srcC);
00987 
00988                     for (count2=0; count2<28; count2++) {
00989                         *samplesC = (int16_t)bytestream_get_be16(&srcC);
00990                         samplesC += avctx->channels;
00991                     }
00992                 } else {
00993                     coeff1 = ea_adpcm_table[ *srcC>>4     ];
00994                     coeff2 = ea_adpcm_table[(*srcC>>4) + 4];
00995                     shift = 20 - (*srcC++ & 0x0F);
00996 
00997                     if (srcC > src_end - 14) break;
00998                     for (count2=0; count2<28; count2++) {
00999                         if (count2 & 1)
01000                             next_sample = sign_extend(*srcC++,    4) << shift;
01001                         else
01002                             next_sample = sign_extend(*srcC >> 4, 4) << shift;
01003 
01004                         next_sample += (current_sample  * coeff1) +
01005                                        (previous_sample * coeff2);
01006                         next_sample = av_clip_int16(next_sample >> 8);
01007 
01008                         previous_sample = current_sample;
01009                         current_sample  = next_sample;
01010                         *samplesC = current_sample;
01011                         samplesC += avctx->channels;
01012                     }
01013                 }
01014             }
01015             if (!count) {
01016                 count = count1;
01017             } else if (count != count1) {
01018                 av_log(avctx, AV_LOG_WARNING, "per-channel sample count mismatch\n");
01019                 count = FFMAX(count, count1);
01020             }
01021 
01022             if (avctx->codec->id != CODEC_ID_ADPCM_EA_R1) {
01023                 c->status[channel].predictor   = current_sample;
01024                 c->status[channel].prev_sample = previous_sample;
01025             }
01026         }
01027 
01028         c->frame.nb_samples = count * 28;
01029         src = src_end;
01030         break;
01031     }
01032     case CODEC_ID_ADPCM_EA_XAS:
01033         for (channel=0; channel<avctx->channels; channel++) {
01034             int coeff[2][4], shift[4];
01035             short *s2, *s = &samples[channel];
01036             for (n=0; n<4; n++, s+=32*avctx->channels) {
01037                 for (i=0; i<2; i++)
01038                     coeff[i][n] = ea_adpcm_table[(src[0]&0x0F)+4*i];
01039                 shift[n] = 20 - (src[2] & 0x0F);
01040                 for (s2=s, i=0; i<2; i++, src+=2, s2+=avctx->channels)
01041                     s2[0] = (src[0]&0xF0) + (src[1]<<8);
01042             }
01043 
01044             for (m=2; m<32; m+=2) {
01045                 s = &samples[m*avctx->channels + channel];
01046                 for (n=0; n<4; n++, src++, s+=32*avctx->channels) {
01047                     for (s2=s, i=0; i<8; i+=4, s2+=avctx->channels) {
01048                         int level = sign_extend(*src >> (4 - i), 4) << shift[n];
01049                         int pred  = s2[-1*avctx->channels] * coeff[0][n]
01050                                   + s2[-2*avctx->channels] * coeff[1][n];
01051                         s2[0] = av_clip_int16((level + pred + 0x80) >> 8);
01052                     }
01053                 }
01054             }
01055         }
01056         break;
01057     case CODEC_ID_ADPCM_IMA_AMV:
01058     case CODEC_ID_ADPCM_IMA_SMJPEG:
01059         if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV) {
01060             c->status[0].predictor = sign_extend(bytestream_get_le16(&src), 16);
01061             c->status[0].step_index = av_clip(bytestream_get_le16(&src), 0, 88);
01062             src += 4;
01063         } else {
01064             c->status[0].predictor = sign_extend(bytestream_get_be16(&src), 16);
01065             c->status[0].step_index = av_clip(bytestream_get_byte(&src), 0, 88);
01066             src += 1;
01067         }
01068 
01069         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01070             char hi, lo;
01071             lo = *src & 0x0F;
01072             hi = *src >> 4;
01073 
01074             if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV)
01075                 FFSWAP(char, hi, lo);
01076 
01077             *samples++ = adpcm_ima_expand_nibble(&c->status[0],
01078                 lo, 3);
01079             *samples++ = adpcm_ima_expand_nibble(&c->status[0],
01080                 hi, 3);
01081         }
01082         break;
01083     case CODEC_ID_ADPCM_CT:
01084         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01085             uint8_t v = *src;
01086             *samples++ = adpcm_ct_expand_nibble(&c->status[0 ], v >> 4  );
01087             *samples++ = adpcm_ct_expand_nibble(&c->status[st], v & 0x0F);
01088         }
01089         break;
01090     case CODEC_ID_ADPCM_SBPRO_4:
01091     case CODEC_ID_ADPCM_SBPRO_3:
01092     case CODEC_ID_ADPCM_SBPRO_2:
01093         if (!c->status[0].step_index) {
01094             /* the first byte is a raw sample */
01095             *samples++ = 128 * (*src++ - 0x80);
01096             if (st)
01097               *samples++ = 128 * (*src++ - 0x80);
01098             c->status[0].step_index = 1;
01099             nb_samples--;
01100         }
01101         if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_4) {
01102             for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01103                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01104                     src[0] >> 4, 4, 0);
01105                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01106                     src[0] & 0x0F, 4, 0);
01107             }
01108         } else if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_3) {
01109             for (n = nb_samples / 3; n > 0; n--, src++) {
01110                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01111                      src[0] >> 5        , 3, 0);
01112                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01113                     (src[0] >> 2) & 0x07, 3, 0);
01114                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01115                     src[0] & 0x03, 2, 0);
01116             }
01117         } else {
01118             for (n = nb_samples >> (2 - st); n > 0; n--, src++) {
01119                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01120                      src[0] >> 6        , 2, 2);
01121                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01122                     (src[0] >> 4) & 0x03, 2, 2);
01123                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01124                     (src[0] >> 2) & 0x03, 2, 2);
01125                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01126                     src[0] & 0x03, 2, 2);
01127             }
01128         }
01129         break;
01130     case CODEC_ID_ADPCM_SWF:
01131     {
01132         GetBitContext gb;
01133         const int *table;
01134         int k0, signmask, nb_bits, count;
01135         int size = buf_size*8;
01136 
01137         init_get_bits(&gb, buf, size);
01138 
01139         //read bits & initial values
01140         nb_bits = get_bits(&gb, 2)+2;
01141         //av_log(NULL,AV_LOG_INFO,"nb_bits: %d\n", nb_bits);
01142         table = swf_index_tables[nb_bits-2];
01143         k0 = 1 << (nb_bits-2);
01144         signmask = 1 << (nb_bits-1);
01145 
01146         while (get_bits_count(&gb) <= size - 22*avctx->channels) {
01147             for (i = 0; i < avctx->channels; i++) {
01148                 *samples++ = c->status[i].predictor = get_sbits(&gb, 16);
01149                 c->status[i].step_index = get_bits(&gb, 6);
01150             }
01151 
01152             for (count = 0; get_bits_count(&gb) <= size - nb_bits*avctx->channels && count < 4095; count++) {
01153                 int i;
01154 
01155                 for (i = 0; i < avctx->channels; i++) {
01156                     // similar to IMA adpcm
01157                     int delta = get_bits(&gb, nb_bits);
01158                     int step = ff_adpcm_step_table[c->status[i].step_index];
01159                     long vpdiff = 0; // vpdiff = (delta+0.5)*step/4
01160                     int k = k0;
01161 
01162                     do {
01163                         if (delta & k)
01164                             vpdiff += step;
01165                         step >>= 1;
01166                         k >>= 1;
01167                     } while(k);
01168                     vpdiff += step;
01169 
01170                     if (delta & signmask)
01171                         c->status[i].predictor -= vpdiff;
01172                     else
01173                         c->status[i].predictor += vpdiff;
01174 
01175                     c->status[i].step_index += table[delta & (~signmask)];
01176 
01177                     c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);
01178                     c->status[i].predictor = av_clip_int16(c->status[i].predictor);
01179 
01180                     *samples++ = c->status[i].predictor;
01181                 }
01182             }
01183         }
01184         src += buf_size;
01185         break;
01186     }
01187     case CODEC_ID_ADPCM_YAMAHA:
01188         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01189             uint8_t v = *src;
01190             *samples++ = adpcm_yamaha_expand_nibble(&c->status[0 ], v & 0x0F);
01191             *samples++ = adpcm_yamaha_expand_nibble(&c->status[st], v >> 4  );
01192         }
01193         break;
01194     case CODEC_ID_ADPCM_THP:
01195     {
01196         int table[2][16];
01197         int prev[2][2];
01198         int ch;
01199 
01200         src += 4; // skip channel size
01201         src += 4; // skip number of samples (already read)
01202 
01203         for (i = 0; i < 32; i++)
01204             table[0][i] = (int16_t)bytestream_get_be16(&src);
01205 
01206         /* Initialize the previous sample.  */
01207         for (i = 0; i < 4; i++)
01208             prev[0][i] = (int16_t)bytestream_get_be16(&src);
01209 
01210         for (ch = 0; ch <= st; ch++) {
01211             samples = (short *)c->frame.data[0] + ch;
01212 
01213             /* Read in every sample for this channel.  */
01214             for (i = 0; i < nb_samples / 14; i++) {
01215                 int index = (*src >> 4) & 7;
01216                 unsigned int exp = *src++ & 15;
01217                 int factor1 = table[ch][index * 2];
01218                 int factor2 = table[ch][index * 2 + 1];
01219 
01220                 /* Decode 14 samples.  */
01221                 for (n = 0; n < 14; n++) {
01222                     int32_t sampledat;
01223                     if(n&1) sampledat = sign_extend(*src++, 4);
01224                     else    sampledat = sign_extend(*src >> 4, 4);
01225 
01226                     sampledat = ((prev[ch][0]*factor1
01227                                 + prev[ch][1]*factor2) >> 11) + (sampledat << exp);
01228                     *samples = av_clip_int16(sampledat);
01229                     prev[ch][1] = prev[ch][0];
01230                     prev[ch][0] = *samples++;
01231 
01232                     /* In case of stereo, skip one sample, this sample
01233                        is for the other channel.  */
01234                     samples += st;
01235                 }
01236             }
01237         }
01238         break;
01239     }
01240 
01241     default:
01242         return -1;
01243     }
01244 
01245     *got_frame_ptr   = 1;
01246     *(AVFrame *)data = c->frame;
01247 
01248     return src - buf;
01249 }
01250 
01251 
01252 #define ADPCM_DECODER(id_, name_, long_name_)               \
01253 AVCodec ff_ ## name_ ## _decoder = {                        \
01254     .name           = #name_,                               \
01255     .type           = AVMEDIA_TYPE_AUDIO,                   \
01256     .id             = id_,                                  \
01257     .priv_data_size = sizeof(ADPCMDecodeContext),           \
01258     .init           = adpcm_decode_init,                    \
01259     .decode         = adpcm_decode_frame,                   \
01260     .capabilities   = CODEC_CAP_DR1,                        \
01261     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),     \
01262 }
01263 
01264 /* Note: Do not forget to add new entries to the Makefile as well. */
01265 ADPCM_DECODER(CODEC_ID_ADPCM_4XM, adpcm_4xm, "ADPCM 4X Movie");
01266 ADPCM_DECODER(CODEC_ID_ADPCM_CT, adpcm_ct, "ADPCM Creative Technology");
01267 ADPCM_DECODER(CODEC_ID_ADPCM_EA, adpcm_ea, "ADPCM Electronic Arts");
01268 ADPCM_DECODER(CODEC_ID_ADPCM_EA_MAXIS_XA, adpcm_ea_maxis_xa, "ADPCM Electronic Arts Maxis CDROM XA");
01269 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R1, adpcm_ea_r1, "ADPCM Electronic Arts R1");
01270 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R2, adpcm_ea_r2, "ADPCM Electronic Arts R2");
01271 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R3, adpcm_ea_r3, "ADPCM Electronic Arts R3");
01272 ADPCM_DECODER(CODEC_ID_ADPCM_EA_XAS, adpcm_ea_xas, "ADPCM Electronic Arts XAS");
01273 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_AMV, adpcm_ima_amv, "ADPCM IMA AMV");
01274 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_APC, adpcm_ima_apc, "ADPCM IMA CRYO APC");
01275 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3, "ADPCM IMA Duck DK3");
01276 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4, "ADPCM IMA Duck DK4");
01277 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs, "ADPCM IMA Electronic Arts EACS");
01278 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead, "ADPCM IMA Electronic Arts SEAD");
01279 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_ISS, adpcm_ima_iss, "ADPCM IMA Funcom ISS");
01280 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt, "ADPCM IMA QuickTime");
01281 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg, "ADPCM IMA Loki SDL MJPEG");
01282 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, "ADPCM IMA WAV");
01283 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws, "ADPCM IMA Westwood");
01284 ADPCM_DECODER(CODEC_ID_ADPCM_MS, adpcm_ms, "ADPCM Microsoft");
01285 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_2, adpcm_sbpro_2, "ADPCM Sound Blaster Pro 2-bit");
01286 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_3, adpcm_sbpro_3, "ADPCM Sound Blaster Pro 2.6-bit");
01287 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_4, adpcm_sbpro_4, "ADPCM Sound Blaster Pro 4-bit");
01288 ADPCM_DECODER(CODEC_ID_ADPCM_SWF, adpcm_swf, "ADPCM Shockwave Flash");
01289 ADPCM_DECODER(CODEC_ID_ADPCM_THP, adpcm_thp, "ADPCM Nintendo Gamecube THP");
01290 ADPCM_DECODER(CODEC_ID_ADPCM_XA, adpcm_xa, "ADPCM CDROM XA");
01291 ADPCM_DECODER(CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha, "ADPCM Yamaha");
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