libavcodec/adpcm.c
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00001 /*
00002  * Copyright (c) 2001-2003 The ffmpeg Project
00003  *
00004  * This file is part of Libav.
00005  *
00006  * Libav 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  * Libav 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 Libav; 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 } ADPCMDecodeContext;
00090 
00091 static av_cold int adpcm_decode_init(AVCodecContext * avctx)
00092 {
00093     ADPCMDecodeContext *c = avctx->priv_data;
00094     unsigned int min_channels = 1;
00095     unsigned int max_channels = 2;
00096 
00097     switch(avctx->codec->id) {
00098     case CODEC_ID_ADPCM_EA:
00099         min_channels = 2;
00100         break;
00101     case CODEC_ID_ADPCM_EA_R1:
00102     case CODEC_ID_ADPCM_EA_R2:
00103     case CODEC_ID_ADPCM_EA_R3:
00104     case CODEC_ID_ADPCM_EA_XAS:
00105         max_channels = 6;
00106         break;
00107     }
00108     if (avctx->channels < min_channels || avctx->channels > max_channels) {
00109         av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");
00110         return AVERROR(EINVAL);
00111     }
00112 
00113     switch(avctx->codec->id) {
00114     case CODEC_ID_ADPCM_CT:
00115         c->status[0].step = c->status[1].step = 511;
00116         break;
00117     case CODEC_ID_ADPCM_IMA_WAV:
00118         if (avctx->bits_per_coded_sample != 4) {
00119             av_log(avctx, AV_LOG_ERROR, "Only 4-bit ADPCM IMA WAV files are supported\n");
00120             return -1;
00121         }
00122         break;
00123     case CODEC_ID_ADPCM_IMA_WS:
00124         if (avctx->extradata && avctx->extradata_size == 2 * 4) {
00125             c->status[0].predictor = AV_RL32(avctx->extradata);
00126             c->status[1].predictor = AV_RL32(avctx->extradata + 4);
00127         }
00128         break;
00129     default:
00130         break;
00131     }
00132     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00133 
00134     avcodec_get_frame_defaults(&c->frame);
00135     avctx->coded_frame = &c->frame;
00136 
00137     return 0;
00138 }
00139 
00140 static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift)
00141 {
00142     int step_index;
00143     int predictor;
00144     int sign, delta, diff, step;
00145 
00146     step = ff_adpcm_step_table[c->step_index];
00147     step_index = c->step_index + ff_adpcm_index_table[(unsigned)nibble];
00148     if (step_index < 0) step_index = 0;
00149     else if (step_index > 88) step_index = 88;
00150 
00151     sign = nibble & 8;
00152     delta = nibble & 7;
00153     /* perform direct multiplication instead of series of jumps proposed by
00154      * the reference ADPCM implementation since modern CPUs can do the mults
00155      * quickly enough */
00156     diff = ((2 * delta + 1) * step) >> shift;
00157     predictor = c->predictor;
00158     if (sign) predictor -= diff;
00159     else predictor += diff;
00160 
00161     c->predictor = av_clip_int16(predictor);
00162     c->step_index = step_index;
00163 
00164     return (short)c->predictor;
00165 }
00166 
00167 static inline int adpcm_ima_qt_expand_nibble(ADPCMChannelStatus *c, int nibble, int shift)
00168 {
00169     int step_index;
00170     int predictor;
00171     int diff, step;
00172 
00173     step = ff_adpcm_step_table[c->step_index];
00174     step_index = c->step_index + ff_adpcm_index_table[nibble];
00175     step_index = av_clip(step_index, 0, 88);
00176 
00177     diff = step >> 3;
00178     if (nibble & 4) diff += step;
00179     if (nibble & 2) diff += step >> 1;
00180     if (nibble & 1) diff += step >> 2;
00181 
00182     if (nibble & 8)
00183         predictor = c->predictor - diff;
00184     else
00185         predictor = c->predictor + diff;
00186 
00187     c->predictor = av_clip_int16(predictor);
00188     c->step_index = step_index;
00189 
00190     return c->predictor;
00191 }
00192 
00193 static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
00194 {
00195     int predictor;
00196 
00197     predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 64;
00198     predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
00199 
00200     c->sample2 = c->sample1;
00201     c->sample1 = av_clip_int16(predictor);
00202     c->idelta = (ff_adpcm_AdaptationTable[(int)nibble] * c->idelta) >> 8;
00203     if (c->idelta < 16) c->idelta = 16;
00204 
00205     return c->sample1;
00206 }
00207 
00208 static inline short adpcm_ct_expand_nibble(ADPCMChannelStatus *c, char nibble)
00209 {
00210     int sign, delta, diff;
00211     int new_step;
00212 
00213     sign = nibble & 8;
00214     delta = nibble & 7;
00215     /* perform direct multiplication instead of series of jumps proposed by
00216      * the reference ADPCM implementation since modern CPUs can do the mults
00217      * quickly enough */
00218     diff = ((2 * delta + 1) * c->step) >> 3;
00219     /* predictor update is not so trivial: predictor is multiplied on 254/256 before updating */
00220     c->predictor = ((c->predictor * 254) >> 8) + (sign ? -diff : diff);
00221     c->predictor = av_clip_int16(c->predictor);
00222     /* calculate new step and clamp it to range 511..32767 */
00223     new_step = (ff_adpcm_AdaptationTable[nibble & 7] * c->step) >> 8;
00224     c->step = av_clip(new_step, 511, 32767);
00225 
00226     return (short)c->predictor;
00227 }
00228 
00229 static inline short adpcm_sbpro_expand_nibble(ADPCMChannelStatus *c, char nibble, int size, int shift)
00230 {
00231     int sign, delta, diff;
00232 
00233     sign = nibble & (1<<(size-1));
00234     delta = nibble & ((1<<(size-1))-1);
00235     diff = delta << (7 + c->step + shift);
00236 
00237     /* clamp result */
00238     c->predictor = av_clip(c->predictor + (sign ? -diff : diff), -16384,16256);
00239 
00240     /* calculate new step */
00241     if (delta >= (2*size - 3) && c->step < 3)
00242         c->step++;
00243     else if (delta == 0 && c->step > 0)
00244         c->step--;
00245 
00246     return (short) c->predictor;
00247 }
00248 
00249 static inline short adpcm_yamaha_expand_nibble(ADPCMChannelStatus *c, unsigned char nibble)
00250 {
00251     if(!c->step) {
00252         c->predictor = 0;
00253         c->step = 127;
00254     }
00255 
00256     c->predictor += (c->step * ff_adpcm_yamaha_difflookup[nibble]) / 8;
00257     c->predictor = av_clip_int16(c->predictor);
00258     c->step = (c->step * ff_adpcm_yamaha_indexscale[nibble]) >> 8;
00259     c->step = av_clip(c->step, 127, 24567);
00260     return c->predictor;
00261 }
00262 
00263 static int xa_decode(AVCodecContext *avctx,
00264                      short *out, const unsigned char *in,
00265                      ADPCMChannelStatus *left, ADPCMChannelStatus *right, int inc)
00266 {
00267     int i, j;
00268     int shift,filter,f0,f1;
00269     int s_1,s_2;
00270     int d,s,t;
00271 
00272     for(i=0;i<4;i++) {
00273 
00274         shift  = 12 - (in[4+i*2] & 15);
00275         filter = in[4+i*2] >> 4;
00276         if (filter > 4) {
00277             av_log(avctx, AV_LOG_ERROR,
00278                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",
00279                    filter);
00280             return AVERROR_INVALIDDATA;
00281         }
00282         f0 = xa_adpcm_table[filter][0];
00283         f1 = xa_adpcm_table[filter][1];
00284 
00285         s_1 = left->sample1;
00286         s_2 = left->sample2;
00287 
00288         for(j=0;j<28;j++) {
00289             d = in[16+i+j*4];
00290 
00291             t = (signed char)(d<<4)>>4;
00292             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
00293             s_2 = s_1;
00294             s_1 = av_clip_int16(s);
00295             *out = s_1;
00296             out += inc;
00297         }
00298 
00299         if (inc==2) { /* stereo */
00300             left->sample1 = s_1;
00301             left->sample2 = s_2;
00302             s_1 = right->sample1;
00303             s_2 = right->sample2;
00304             out = out + 1 - 28*2;
00305         }
00306 
00307         shift  = 12 - (in[5+i*2] & 15);
00308         filter = in[5+i*2] >> 4;
00309         if (filter > 4) {
00310             av_log(avctx, AV_LOG_ERROR,
00311                    "Invalid XA-ADPCM filter %d (max. allowed is 4)\n",
00312                    filter);
00313             return AVERROR_INVALIDDATA;
00314         }
00315         f0 = xa_adpcm_table[filter][0];
00316         f1 = xa_adpcm_table[filter][1];
00317 
00318         for(j=0;j<28;j++) {
00319             d = in[16+i+j*4];
00320 
00321             t = (signed char)d >> 4;
00322             s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
00323             s_2 = s_1;
00324             s_1 = av_clip_int16(s);
00325             *out = s_1;
00326             out += inc;
00327         }
00328 
00329         if (inc==2) { /* stereo */
00330             right->sample1 = s_1;
00331             right->sample2 = s_2;
00332             out -= 1;
00333         } else {
00334             left->sample1 = s_1;
00335             left->sample2 = s_2;
00336         }
00337     }
00338 
00339     return 0;
00340 }
00341 
00351 static int get_nb_samples(AVCodecContext *avctx, const uint8_t *buf,
00352                           int buf_size, int *coded_samples)
00353 {
00354     ADPCMDecodeContext *s = avctx->priv_data;
00355     int nb_samples        = 0;
00356     int ch                = avctx->channels;
00357     int has_coded_samples = 0;
00358     int header_size;
00359 
00360     *coded_samples = 0;
00361 
00362     switch (avctx->codec->id) {
00363     /* constant, only check buf_size */
00364     case CODEC_ID_ADPCM_EA_XAS:
00365         if (buf_size < 76 * ch)
00366             return 0;
00367         nb_samples = 128;
00368         break;
00369     case CODEC_ID_ADPCM_IMA_QT:
00370         if (buf_size < 34 * ch)
00371             return 0;
00372         nb_samples = 64;
00373         break;
00374     /* simple 4-bit adpcm */
00375     case CODEC_ID_ADPCM_CT:
00376     case CODEC_ID_ADPCM_IMA_EA_SEAD:
00377     case CODEC_ID_ADPCM_IMA_WS:
00378     case CODEC_ID_ADPCM_YAMAHA:
00379         nb_samples = buf_size * 2 / ch;
00380         break;
00381     }
00382     if (nb_samples)
00383         return nb_samples;
00384 
00385     /* simple 4-bit adpcm, with header */
00386     header_size = 0;
00387     switch (avctx->codec->id) {
00388         case CODEC_ID_ADPCM_4XM:
00389         case CODEC_ID_ADPCM_IMA_ISS:     header_size = 4 * ch;      break;
00390         case CODEC_ID_ADPCM_IMA_AMV:     header_size = 8;           break;
00391         case CODEC_ID_ADPCM_IMA_SMJPEG:  header_size = 4;           break;
00392     }
00393     if (header_size > 0)
00394         return (buf_size - header_size) * 2 / ch;
00395 
00396     /* more complex formats */
00397     switch (avctx->codec->id) {
00398     case CODEC_ID_ADPCM_EA:
00399         has_coded_samples = 1;
00400         if (buf_size < 4)
00401             return 0;
00402         *coded_samples  = AV_RL32(buf);
00403         *coded_samples -= *coded_samples % 28;
00404         nb_samples      = (buf_size - 12) / 30 * 28;
00405         break;
00406     case CODEC_ID_ADPCM_IMA_EA_EACS:
00407         has_coded_samples = 1;
00408         if (buf_size < 4)
00409             return 0;
00410         *coded_samples = AV_RL32(buf);
00411         nb_samples     = (buf_size - (4 + 8 * ch)) * 2 / ch;
00412         break;
00413     case CODEC_ID_ADPCM_EA_MAXIS_XA:
00414         nb_samples = ((buf_size - ch) / (2 * ch)) * 2 * ch;
00415         break;
00416     case CODEC_ID_ADPCM_EA_R1:
00417     case CODEC_ID_ADPCM_EA_R2:
00418     case CODEC_ID_ADPCM_EA_R3:
00419         /* maximum number of samples */
00420         /* has internal offsets and a per-frame switch to signal raw 16-bit */
00421         has_coded_samples = 1;
00422         if (buf_size < 4)
00423             return 0;
00424         switch (avctx->codec->id) {
00425         case CODEC_ID_ADPCM_EA_R1:
00426             header_size    = 4 + 9 * ch;
00427             *coded_samples = AV_RL32(buf);
00428             break;
00429         case CODEC_ID_ADPCM_EA_R2:
00430             header_size    = 4 + 5 * ch;
00431             *coded_samples = AV_RL32(buf);
00432             break;
00433         case CODEC_ID_ADPCM_EA_R3:
00434             header_size    = 4 + 5 * ch;
00435             *coded_samples = AV_RB32(buf);
00436             break;
00437         }
00438         *coded_samples -= *coded_samples % 28;
00439         nb_samples      = (buf_size - header_size) * 2 / ch;
00440         nb_samples     -= nb_samples % 28;
00441         break;
00442     case CODEC_ID_ADPCM_IMA_DK3:
00443         if (avctx->block_align > 0)
00444             buf_size = FFMIN(buf_size, avctx->block_align);
00445         nb_samples = ((buf_size - 16) * 8 / 3) / ch;
00446         break;
00447     case CODEC_ID_ADPCM_IMA_DK4:
00448         nb_samples = 1 + (buf_size - 4 * ch) * 2 / ch;
00449         break;
00450     case CODEC_ID_ADPCM_IMA_WAV:
00451         if (avctx->block_align > 0)
00452             buf_size = FFMIN(buf_size, avctx->block_align);
00453         nb_samples = 1 + (buf_size - 4 * ch) / (4 * ch) * 8;
00454         break;
00455     case CODEC_ID_ADPCM_MS:
00456         if (avctx->block_align > 0)
00457             buf_size = FFMIN(buf_size, avctx->block_align);
00458         nb_samples = 2 + (buf_size - 7 * ch) * 2 / ch;
00459         break;
00460     case CODEC_ID_ADPCM_SBPRO_2:
00461     case CODEC_ID_ADPCM_SBPRO_3:
00462     case CODEC_ID_ADPCM_SBPRO_4:
00463     {
00464         int samples_per_byte;
00465         switch (avctx->codec->id) {
00466         case CODEC_ID_ADPCM_SBPRO_2: samples_per_byte = 4; break;
00467         case CODEC_ID_ADPCM_SBPRO_3: samples_per_byte = 3; break;
00468         case CODEC_ID_ADPCM_SBPRO_4: samples_per_byte = 2; break;
00469         }
00470         if (!s->status[0].step_index) {
00471             nb_samples++;
00472             buf_size -= ch;
00473         }
00474         nb_samples += buf_size * samples_per_byte / ch;
00475         break;
00476     }
00477     case CODEC_ID_ADPCM_SWF:
00478     {
00479         int buf_bits       = buf_size * 8 - 2;
00480         int nbits          = (buf[0] >> 6) + 2;
00481         int block_hdr_size = 22 * ch;
00482         int block_size     = block_hdr_size + nbits * ch * 4095;
00483         int nblocks        = buf_bits / block_size;
00484         int bits_left      = buf_bits - nblocks * block_size;
00485         nb_samples         = nblocks * 4096;
00486         if (bits_left >= block_hdr_size)
00487             nb_samples += 1 + (bits_left - block_hdr_size) / (nbits * ch);
00488         break;
00489     }
00490     case CODEC_ID_ADPCM_THP:
00491         has_coded_samples = 1;
00492         if (buf_size < 8)
00493             return 0;
00494         *coded_samples  = AV_RB32(&buf[4]);
00495         *coded_samples -= *coded_samples % 14;
00496         nb_samples      = (buf_size - 80) / (8 * ch) * 14;
00497         break;
00498     case CODEC_ID_ADPCM_XA:
00499         nb_samples = (buf_size / 128) * 224 / ch;
00500         break;
00501     }
00502 
00503     /* validate coded sample count */
00504     if (has_coded_samples && (*coded_samples <= 0 || *coded_samples > nb_samples))
00505         return AVERROR_INVALIDDATA;
00506 
00507     return nb_samples;
00508 }
00509 
00510 /* DK3 ADPCM support macro */
00511 #define DK3_GET_NEXT_NIBBLE() \
00512     if (decode_top_nibble_next) \
00513     { \
00514         nibble = last_byte >> 4; \
00515         decode_top_nibble_next = 0; \
00516     } \
00517     else \
00518     { \
00519         if (end_of_packet) \
00520             break; \
00521         last_byte = *src++; \
00522         if (src >= buf + buf_size) \
00523             end_of_packet = 1; \
00524         nibble = last_byte & 0x0F; \
00525         decode_top_nibble_next = 1; \
00526     }
00527 
00528 static int adpcm_decode_frame(AVCodecContext *avctx, void *data,
00529                               int *got_frame_ptr, AVPacket *avpkt)
00530 {
00531     const uint8_t *buf = avpkt->data;
00532     int buf_size = avpkt->size;
00533     ADPCMDecodeContext *c = avctx->priv_data;
00534     ADPCMChannelStatus *cs;
00535     int n, m, channel, i;
00536     short *samples;
00537     const uint8_t *src;
00538     int st; /* stereo */
00539     int count1, count2;
00540     int nb_samples, coded_samples, ret;
00541 
00542     nb_samples = get_nb_samples(avctx, buf, buf_size, &coded_samples);
00543     if (nb_samples <= 0) {
00544         av_log(avctx, AV_LOG_ERROR, "invalid number of samples in packet\n");
00545         return AVERROR_INVALIDDATA;
00546     }
00547 
00548     /* get output buffer */
00549     c->frame.nb_samples = nb_samples;
00550     if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) {
00551         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00552         return ret;
00553     }
00554     samples = (short *)c->frame.data[0];
00555 
00556     /* use coded_samples when applicable */
00557     /* it is always <= nb_samples, so the output buffer will be large enough */
00558     if (coded_samples) {
00559         if (coded_samples != nb_samples)
00560             av_log(avctx, AV_LOG_WARNING, "mismatch in coded sample count\n");
00561         c->frame.nb_samples = nb_samples = coded_samples;
00562     }
00563 
00564     src = buf;
00565 
00566     st = avctx->channels == 2 ? 1 : 0;
00567 
00568     switch(avctx->codec->id) {
00569     case CODEC_ID_ADPCM_IMA_QT:
00570         /* In QuickTime, IMA is encoded by chunks of 34 bytes (=64 samples).
00571            Channel data is interleaved per-chunk. */
00572         for (channel = 0; channel < avctx->channels; channel++) {
00573             int16_t predictor;
00574             int step_index;
00575             cs = &(c->status[channel]);
00576             /* (pppppp) (piiiiiii) */
00577 
00578             /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
00579             predictor = AV_RB16(src);
00580             step_index = predictor & 0x7F;
00581             predictor &= 0xFF80;
00582 
00583             src += 2;
00584 
00585             if (cs->step_index == step_index) {
00586                 int diff = (int)predictor - cs->predictor;
00587                 if (diff < 0)
00588                     diff = - diff;
00589                 if (diff > 0x7f)
00590                     goto update;
00591             } else {
00592             update:
00593                 cs->step_index = step_index;
00594                 cs->predictor = predictor;
00595             }
00596 
00597             if (cs->step_index > 88){
00598                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
00599                 cs->step_index = 88;
00600             }
00601 
00602             samples = (short *)c->frame.data[0] + channel;
00603 
00604             for (m = 0; m < 32; m++) {
00605                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] & 0x0F, 3);
00606                 samples += avctx->channels;
00607                 *samples = adpcm_ima_qt_expand_nibble(cs, src[0] >> 4  , 3);
00608                 samples += avctx->channels;
00609                 src ++;
00610             }
00611         }
00612         break;
00613     case CODEC_ID_ADPCM_IMA_WAV:
00614         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00615             buf_size = avctx->block_align;
00616 
00617         for(i=0; i<avctx->channels; i++){
00618             cs = &(c->status[i]);
00619             cs->predictor = *samples++ = (int16_t)bytestream_get_le16(&src);
00620 
00621             cs->step_index = *src++;
00622             if (cs->step_index > 88){
00623                 av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
00624                 cs->step_index = 88;
00625             }
00626             if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null but is %d!!\n", src[-1]); /* unused */
00627         }
00628 
00629         for (n = (nb_samples - 1) / 8; n > 0; n--) {
00630             for (i = 0; i < avctx->channels; i++) {
00631                 cs = &c->status[i];
00632                 for (m = 0; m < 4; m++) {
00633                     uint8_t v = *src++;
00634                     *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 3);
00635                     samples += avctx->channels;
00636                     *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 3);
00637                     samples += avctx->channels;
00638                 }
00639                 samples -= 8 * avctx->channels - 1;
00640             }
00641             samples += 7 * avctx->channels;
00642         }
00643         break;
00644     case CODEC_ID_ADPCM_4XM:
00645         for (i = 0; i < avctx->channels; i++)
00646             c->status[i].predictor= (int16_t)bytestream_get_le16(&src);
00647 
00648         for (i = 0; i < avctx->channels; i++) {
00649             c->status[i].step_index= (int16_t)bytestream_get_le16(&src);
00650             c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);
00651         }
00652 
00653         for (i = 0; i < avctx->channels; i++) {
00654             samples = (short *)c->frame.data[0] + i;
00655             cs = &c->status[i];
00656             for (n = nb_samples >> 1; n > 0; n--, src++) {
00657                 uint8_t v = *src;
00658                 *samples = adpcm_ima_expand_nibble(cs, v & 0x0F, 4);
00659                 samples += avctx->channels;
00660                 *samples = adpcm_ima_expand_nibble(cs, v >> 4  , 4);
00661                 samples += avctx->channels;
00662             }
00663         }
00664         break;
00665     case CODEC_ID_ADPCM_MS:
00666     {
00667         int block_predictor;
00668 
00669         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00670             buf_size = avctx->block_align;
00671 
00672         block_predictor = av_clip(*src++, 0, 6);
00673         c->status[0].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];
00674         c->status[0].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];
00675         if (st) {
00676             block_predictor = av_clip(*src++, 0, 6);
00677             c->status[1].coeff1 = ff_adpcm_AdaptCoeff1[block_predictor];
00678             c->status[1].coeff2 = ff_adpcm_AdaptCoeff2[block_predictor];
00679         }
00680         c->status[0].idelta = (int16_t)bytestream_get_le16(&src);
00681         if (st){
00682             c->status[1].idelta = (int16_t)bytestream_get_le16(&src);
00683         }
00684 
00685         c->status[0].sample1 = bytestream_get_le16(&src);
00686         if (st) c->status[1].sample1 = bytestream_get_le16(&src);
00687         c->status[0].sample2 = bytestream_get_le16(&src);
00688         if (st) c->status[1].sample2 = bytestream_get_le16(&src);
00689 
00690         *samples++ = c->status[0].sample2;
00691         if (st) *samples++ = c->status[1].sample2;
00692         *samples++ = c->status[0].sample1;
00693         if (st) *samples++ = c->status[1].sample1;
00694         for(n = (nb_samples - 2) >> (1 - st); n > 0; n--, src++) {
00695             *samples++ = adpcm_ms_expand_nibble(&c->status[0 ], src[0] >> 4  );
00696             *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
00697         }
00698         break;
00699     }
00700     case CODEC_ID_ADPCM_IMA_DK4:
00701         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00702             buf_size = avctx->block_align;
00703 
00704         for (channel = 0; channel < avctx->channels; channel++) {
00705             cs = &c->status[channel];
00706             cs->predictor  = (int16_t)bytestream_get_le16(&src);
00707             cs->step_index = av_clip(*src++, 0, 88);
00708             src++;
00709             *samples++ = cs->predictor;
00710         }
00711         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00712             uint8_t v = *src;
00713             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v >> 4  , 3);
00714             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);
00715         }
00716         break;
00717     case CODEC_ID_ADPCM_IMA_DK3:
00718     {
00719         unsigned char last_byte = 0;
00720         unsigned char nibble;
00721         int decode_top_nibble_next = 0;
00722         int end_of_packet = 0;
00723         int diff_channel;
00724 
00725         if (avctx->block_align != 0 && buf_size > avctx->block_align)
00726             buf_size = avctx->block_align;
00727 
00728         c->status[0].predictor  = (int16_t)AV_RL16(src + 10);
00729         c->status[1].predictor  = (int16_t)AV_RL16(src + 12);
00730         c->status[0].step_index = av_clip(src[14], 0, 88);
00731         c->status[1].step_index = av_clip(src[15], 0, 88);
00732         /* sign extend the predictors */
00733         src += 16;
00734         diff_channel = c->status[1].predictor;
00735 
00736         /* the DK3_GET_NEXT_NIBBLE macro issues the break statement when
00737          * the buffer is consumed */
00738         while (1) {
00739 
00740             /* for this algorithm, c->status[0] is the sum channel and
00741              * c->status[1] is the diff channel */
00742 
00743             /* process the first predictor of the sum channel */
00744             DK3_GET_NEXT_NIBBLE();
00745             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
00746 
00747             /* process the diff channel predictor */
00748             DK3_GET_NEXT_NIBBLE();
00749             adpcm_ima_expand_nibble(&c->status[1], nibble, 3);
00750 
00751             /* process the first pair of stereo PCM samples */
00752             diff_channel = (diff_channel + c->status[1].predictor) / 2;
00753             *samples++ = c->status[0].predictor + c->status[1].predictor;
00754             *samples++ = c->status[0].predictor - c->status[1].predictor;
00755 
00756             /* process the second predictor of the sum channel */
00757             DK3_GET_NEXT_NIBBLE();
00758             adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
00759 
00760             /* process the second 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         break;
00766     }
00767     case CODEC_ID_ADPCM_IMA_ISS:
00768         for (channel = 0; channel < avctx->channels; channel++) {
00769             cs = &c->status[channel];
00770             cs->predictor  = (int16_t)bytestream_get_le16(&src);
00771             cs->step_index = av_clip(*src++, 0, 88);
00772             src++;
00773         }
00774 
00775         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00776             uint8_t v1, v2;
00777             uint8_t v = *src;
00778             /* nibbles are swapped for mono */
00779             if (st) {
00780                 v1 = v >> 4;
00781                 v2 = v & 0x0F;
00782             } else {
00783                 v2 = v >> 4;
00784                 v1 = v & 0x0F;
00785             }
00786             *samples++ = adpcm_ima_expand_nibble(&c->status[0 ], v1, 3);
00787             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v2, 3);
00788         }
00789         break;
00790     case CODEC_ID_ADPCM_IMA_WS:
00791         while (src < buf + buf_size) {
00792             uint8_t v = *src++;
00793             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  v >> 4  , 3);
00794             *samples++ = adpcm_ima_expand_nibble(&c->status[st], v & 0x0F, 3);
00795         }
00796         break;
00797     case CODEC_ID_ADPCM_XA:
00798         while (buf_size >= 128) {
00799             if ((ret = xa_decode(avctx, samples, src, &c->status[0],
00800                                  &c->status[1], avctx->channels)) < 0)
00801                 return ret;
00802             src += 128;
00803             samples += 28 * 8;
00804             buf_size -= 128;
00805         }
00806         break;
00807     case CODEC_ID_ADPCM_IMA_EA_EACS:
00808         src += 4; // skip sample count (already read)
00809 
00810         for (i=0; i<=st; i++)
00811             c->status[i].step_index = av_clip(bytestream_get_le32(&src), 0, 88);
00812         for (i=0; i<=st; i++)
00813             c->status[i].predictor  = bytestream_get_le32(&src);
00814 
00815         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00816             *samples++ = adpcm_ima_expand_nibble(&c->status[0],  *src>>4,   3);
00817             *samples++ = adpcm_ima_expand_nibble(&c->status[st], *src&0x0F, 3);
00818         }
00819         break;
00820     case CODEC_ID_ADPCM_IMA_EA_SEAD:
00821         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
00822             *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] >> 4, 6);
00823             *samples++ = adpcm_ima_expand_nibble(&c->status[st],src[0]&0x0F, 6);
00824         }
00825         break;
00826     case CODEC_ID_ADPCM_EA:
00827     {
00828         int32_t previous_left_sample, previous_right_sample;
00829         int32_t current_left_sample, current_right_sample;
00830         int32_t next_left_sample, next_right_sample;
00831         int32_t coeff1l, coeff2l, coeff1r, coeff2r;
00832         uint8_t shift_left, shift_right;
00833 
00834         /* Each EA ADPCM frame has a 12-byte header followed by 30-byte pieces,
00835            each coding 28 stereo samples. */
00836 
00837         src += 4; // skip sample count (already read)
00838 
00839         current_left_sample   = (int16_t)bytestream_get_le16(&src);
00840         previous_left_sample  = (int16_t)bytestream_get_le16(&src);
00841         current_right_sample  = (int16_t)bytestream_get_le16(&src);
00842         previous_right_sample = (int16_t)bytestream_get_le16(&src);
00843 
00844         for (count1 = 0; count1 < nb_samples / 28; count1++) {
00845             coeff1l = ea_adpcm_table[ *src >> 4       ];
00846             coeff2l = ea_adpcm_table[(*src >> 4  ) + 4];
00847             coeff1r = ea_adpcm_table[*src & 0x0F];
00848             coeff2r = ea_adpcm_table[(*src & 0x0F) + 4];
00849             src++;
00850 
00851             shift_left  = 20 - (*src >> 4);
00852             shift_right = 20 - (*src & 0x0F);
00853             src++;
00854 
00855             for (count2 = 0; count2 < 28; count2++) {
00856                 next_left_sample  = sign_extend(*src >> 4, 4) << shift_left;
00857                 next_right_sample = sign_extend(*src,      4) << shift_right;
00858                 src++;
00859 
00860                 next_left_sample = (next_left_sample +
00861                     (current_left_sample * coeff1l) +
00862                     (previous_left_sample * coeff2l) + 0x80) >> 8;
00863                 next_right_sample = (next_right_sample +
00864                     (current_right_sample * coeff1r) +
00865                     (previous_right_sample * coeff2r) + 0x80) >> 8;
00866 
00867                 previous_left_sample = current_left_sample;
00868                 current_left_sample = av_clip_int16(next_left_sample);
00869                 previous_right_sample = current_right_sample;
00870                 current_right_sample = av_clip_int16(next_right_sample);
00871                 *samples++ = (unsigned short)current_left_sample;
00872                 *samples++ = (unsigned short)current_right_sample;
00873             }
00874         }
00875 
00876         if (src - buf == buf_size - 2)
00877             src += 2; // Skip terminating 0x0000
00878 
00879         break;
00880     }
00881     case CODEC_ID_ADPCM_EA_MAXIS_XA:
00882     {
00883         int coeff[2][2], shift[2];
00884 
00885         for(channel = 0; channel < avctx->channels; channel++) {
00886             for (i=0; i<2; i++)
00887                 coeff[channel][i] = ea_adpcm_table[(*src >> 4) + 4*i];
00888             shift[channel] = 20 - (*src & 0x0F);
00889             src++;
00890         }
00891         for (count1 = 0; count1 < nb_samples / 2; count1++) {
00892             for(i = 4; i >= 0; i-=4) { /* Pairwise samples LL RR (st) or LL LL (mono) */
00893                 for(channel = 0; channel < avctx->channels; channel++) {
00894                     int32_t sample = sign_extend(src[channel] >> i, 4) << shift[channel];
00895                     sample = (sample +
00896                              c->status[channel].sample1 * coeff[channel][0] +
00897                              c->status[channel].sample2 * coeff[channel][1] + 0x80) >> 8;
00898                     c->status[channel].sample2 = c->status[channel].sample1;
00899                     c->status[channel].sample1 = av_clip_int16(sample);
00900                     *samples++ = c->status[channel].sample1;
00901                 }
00902             }
00903             src+=avctx->channels;
00904         }
00905         /* consume whole packet */
00906         src = buf + buf_size;
00907         break;
00908     }
00909     case CODEC_ID_ADPCM_EA_R1:
00910     case CODEC_ID_ADPCM_EA_R2:
00911     case CODEC_ID_ADPCM_EA_R3: {
00912         /* channel numbering
00913            2chan: 0=fl, 1=fr
00914            4chan: 0=fl, 1=rl, 2=fr, 3=rr
00915            6chan: 0=fl, 1=c,  2=fr, 3=rl,  4=rr, 5=sub */
00916         const int big_endian = avctx->codec->id == CODEC_ID_ADPCM_EA_R3;
00917         int32_t previous_sample, current_sample, next_sample;
00918         int32_t coeff1, coeff2;
00919         uint8_t shift;
00920         unsigned int channel;
00921         uint16_t *samplesC;
00922         const uint8_t *srcC;
00923         const uint8_t *src_end = buf + buf_size;
00924         int count = 0;
00925 
00926         src += 4; // skip sample count (already read)
00927 
00928         for (channel=0; channel<avctx->channels; channel++) {
00929             int32_t offset = (big_endian ? bytestream_get_be32(&src)
00930                                          : bytestream_get_le32(&src))
00931                            + (avctx->channels-channel-1) * 4;
00932 
00933             if ((offset < 0) || (offset >= src_end - src - 4)) break;
00934             srcC  = src + offset;
00935             samplesC = samples + channel;
00936 
00937             if (avctx->codec->id == CODEC_ID_ADPCM_EA_R1) {
00938                 current_sample  = (int16_t)bytestream_get_le16(&srcC);
00939                 previous_sample = (int16_t)bytestream_get_le16(&srcC);
00940             } else {
00941                 current_sample  = c->status[channel].predictor;
00942                 previous_sample = c->status[channel].prev_sample;
00943             }
00944 
00945             for (count1 = 0; count1 < nb_samples / 28; count1++) {
00946                 if (*srcC == 0xEE) {  /* only seen in R2 and R3 */
00947                     srcC++;
00948                     if (srcC > src_end - 30*2) break;
00949                     current_sample  = (int16_t)bytestream_get_be16(&srcC);
00950                     previous_sample = (int16_t)bytestream_get_be16(&srcC);
00951 
00952                     for (count2=0; count2<28; count2++) {
00953                         *samplesC = (int16_t)bytestream_get_be16(&srcC);
00954                         samplesC += avctx->channels;
00955                     }
00956                 } else {
00957                     coeff1 = ea_adpcm_table[ *srcC>>4     ];
00958                     coeff2 = ea_adpcm_table[(*srcC>>4) + 4];
00959                     shift = 20 - (*srcC++ & 0x0F);
00960 
00961                     if (srcC > src_end - 14) break;
00962                     for (count2=0; count2<28; count2++) {
00963                         if (count2 & 1)
00964                             next_sample = sign_extend(*srcC++,    4) << shift;
00965                         else
00966                             next_sample = sign_extend(*srcC >> 4, 4) << shift;
00967 
00968                         next_sample += (current_sample  * coeff1) +
00969                                        (previous_sample * coeff2);
00970                         next_sample = av_clip_int16(next_sample >> 8);
00971 
00972                         previous_sample = current_sample;
00973                         current_sample  = next_sample;
00974                         *samplesC = current_sample;
00975                         samplesC += avctx->channels;
00976                     }
00977                 }
00978             }
00979             if (!count) {
00980                 count = count1;
00981             } else if (count != count1) {
00982                 av_log(avctx, AV_LOG_WARNING, "per-channel sample count mismatch\n");
00983                 count = FFMAX(count, count1);
00984             }
00985 
00986             if (avctx->codec->id != CODEC_ID_ADPCM_EA_R1) {
00987                 c->status[channel].predictor   = current_sample;
00988                 c->status[channel].prev_sample = previous_sample;
00989             }
00990         }
00991 
00992         c->frame.nb_samples = count * 28;
00993         src = src_end;
00994         break;
00995     }
00996     case CODEC_ID_ADPCM_EA_XAS:
00997         for (channel=0; channel<avctx->channels; channel++) {
00998             int coeff[2][4], shift[4];
00999             short *s2, *s = &samples[channel];
01000             for (n=0; n<4; n++, s+=32*avctx->channels) {
01001                 for (i=0; i<2; i++)
01002                     coeff[i][n] = ea_adpcm_table[(src[0]&0x0F)+4*i];
01003                 shift[n] = 20 - (src[2] & 0x0F);
01004                 for (s2=s, i=0; i<2; i++, src+=2, s2+=avctx->channels)
01005                     s2[0] = (src[0]&0xF0) + (src[1]<<8);
01006             }
01007 
01008             for (m=2; m<32; m+=2) {
01009                 s = &samples[m*avctx->channels + channel];
01010                 for (n=0; n<4; n++, src++, s+=32*avctx->channels) {
01011                     for (s2=s, i=0; i<8; i+=4, s2+=avctx->channels) {
01012                         int level = sign_extend(*src >> (4 - i), 4) << shift[n];
01013                         int pred  = s2[-1*avctx->channels] * coeff[0][n]
01014                                   + s2[-2*avctx->channels] * coeff[1][n];
01015                         s2[0] = av_clip_int16((level + pred + 0x80) >> 8);
01016                     }
01017                 }
01018             }
01019         }
01020         break;
01021     case CODEC_ID_ADPCM_IMA_AMV:
01022     case CODEC_ID_ADPCM_IMA_SMJPEG:
01023         if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV) {
01024             c->status[0].predictor = sign_extend(bytestream_get_le16(&src), 16);
01025             c->status[0].step_index = av_clip(bytestream_get_le16(&src), 0, 88);
01026             src += 4;
01027         } else {
01028             c->status[0].predictor = sign_extend(bytestream_get_be16(&src), 16);
01029             c->status[0].step_index = av_clip(bytestream_get_byte(&src), 0, 88);
01030             src += 1;
01031         }
01032 
01033         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01034             char hi, lo;
01035             lo = *src & 0x0F;
01036             hi = *src >> 4;
01037 
01038             if (avctx->codec->id == CODEC_ID_ADPCM_IMA_AMV)
01039                 FFSWAP(char, hi, lo);
01040 
01041             *samples++ = adpcm_ima_expand_nibble(&c->status[0],
01042                 lo, 3);
01043             *samples++ = adpcm_ima_expand_nibble(&c->status[0],
01044                 hi, 3);
01045         }
01046         break;
01047     case CODEC_ID_ADPCM_CT:
01048         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01049             uint8_t v = *src;
01050             *samples++ = adpcm_ct_expand_nibble(&c->status[0 ], v >> 4  );
01051             *samples++ = adpcm_ct_expand_nibble(&c->status[st], v & 0x0F);
01052         }
01053         break;
01054     case CODEC_ID_ADPCM_SBPRO_4:
01055     case CODEC_ID_ADPCM_SBPRO_3:
01056     case CODEC_ID_ADPCM_SBPRO_2:
01057         if (!c->status[0].step_index) {
01058             /* the first byte is a raw sample */
01059             *samples++ = 128 * (*src++ - 0x80);
01060             if (st)
01061               *samples++ = 128 * (*src++ - 0x80);
01062             c->status[0].step_index = 1;
01063             nb_samples--;
01064         }
01065         if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_4) {
01066             for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01067                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01068                     src[0] >> 4, 4, 0);
01069                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01070                     src[0] & 0x0F, 4, 0);
01071             }
01072         } else if (avctx->codec->id == CODEC_ID_ADPCM_SBPRO_3) {
01073             for (n = nb_samples / 3; n > 0; n--, src++) {
01074                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01075                      src[0] >> 5        , 3, 0);
01076                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01077                     (src[0] >> 2) & 0x07, 3, 0);
01078                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01079                     src[0] & 0x03, 2, 0);
01080             }
01081         } else {
01082             for (n = nb_samples >> (2 - st); n > 0; n--, src++) {
01083                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01084                      src[0] >> 6        , 2, 2);
01085                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01086                     (src[0] >> 4) & 0x03, 2, 2);
01087                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[0],
01088                     (src[0] >> 2) & 0x03, 2, 2);
01089                 *samples++ = adpcm_sbpro_expand_nibble(&c->status[st],
01090                     src[0] & 0x03, 2, 2);
01091             }
01092         }
01093         break;
01094     case CODEC_ID_ADPCM_SWF:
01095     {
01096         GetBitContext gb;
01097         const int *table;
01098         int k0, signmask, nb_bits, count;
01099         int size = buf_size*8;
01100 
01101         init_get_bits(&gb, buf, size);
01102 
01103         //read bits & initial values
01104         nb_bits = get_bits(&gb, 2)+2;
01105         //av_log(NULL,AV_LOG_INFO,"nb_bits: %d\n", nb_bits);
01106         table = swf_index_tables[nb_bits-2];
01107         k0 = 1 << (nb_bits-2);
01108         signmask = 1 << (nb_bits-1);
01109 
01110         while (get_bits_count(&gb) <= size - 22*avctx->channels) {
01111             for (i = 0; i < avctx->channels; i++) {
01112                 *samples++ = c->status[i].predictor = get_sbits(&gb, 16);
01113                 c->status[i].step_index = get_bits(&gb, 6);
01114             }
01115 
01116             for (count = 0; get_bits_count(&gb) <= size - nb_bits*avctx->channels && count < 4095; count++) {
01117                 int i;
01118 
01119                 for (i = 0; i < avctx->channels; i++) {
01120                     // similar to IMA adpcm
01121                     int delta = get_bits(&gb, nb_bits);
01122                     int step = ff_adpcm_step_table[c->status[i].step_index];
01123                     long vpdiff = 0; // vpdiff = (delta+0.5)*step/4
01124                     int k = k0;
01125 
01126                     do {
01127                         if (delta & k)
01128                             vpdiff += step;
01129                         step >>= 1;
01130                         k >>= 1;
01131                     } while(k);
01132                     vpdiff += step;
01133 
01134                     if (delta & signmask)
01135                         c->status[i].predictor -= vpdiff;
01136                     else
01137                         c->status[i].predictor += vpdiff;
01138 
01139                     c->status[i].step_index += table[delta & (~signmask)];
01140 
01141                     c->status[i].step_index = av_clip(c->status[i].step_index, 0, 88);
01142                     c->status[i].predictor = av_clip_int16(c->status[i].predictor);
01143 
01144                     *samples++ = c->status[i].predictor;
01145                 }
01146             }
01147         }
01148         src += buf_size;
01149         break;
01150     }
01151     case CODEC_ID_ADPCM_YAMAHA:
01152         for (n = nb_samples >> (1 - st); n > 0; n--, src++) {
01153             uint8_t v = *src;
01154             *samples++ = adpcm_yamaha_expand_nibble(&c->status[0 ], v & 0x0F);
01155             *samples++ = adpcm_yamaha_expand_nibble(&c->status[st], v >> 4  );
01156         }
01157         break;
01158     case CODEC_ID_ADPCM_THP:
01159     {
01160         int table[2][16];
01161         int prev[2][2];
01162         int ch;
01163 
01164         src += 4; // skip channel size
01165         src += 4; // skip number of samples (already read)
01166 
01167         for (i = 0; i < 32; i++)
01168             table[0][i] = (int16_t)bytestream_get_be16(&src);
01169 
01170         /* Initialize the previous sample.  */
01171         for (i = 0; i < 4; i++)
01172             prev[0][i] = (int16_t)bytestream_get_be16(&src);
01173 
01174         for (ch = 0; ch <= st; ch++) {
01175             samples = (short *)c->frame.data[0] + ch;
01176 
01177             /* Read in every sample for this channel.  */
01178             for (i = 0; i < nb_samples / 14; i++) {
01179                 int index = (*src >> 4) & 7;
01180                 unsigned int exp = *src++ & 15;
01181                 int factor1 = table[ch][index * 2];
01182                 int factor2 = table[ch][index * 2 + 1];
01183 
01184                 /* Decode 14 samples.  */
01185                 for (n = 0; n < 14; n++) {
01186                     int32_t sampledat;
01187                     if(n&1) sampledat = sign_extend(*src++, 4);
01188                     else    sampledat = sign_extend(*src >> 4, 4);
01189 
01190                     sampledat = ((prev[ch][0]*factor1
01191                                 + prev[ch][1]*factor2) >> 11) + (sampledat << exp);
01192                     *samples = av_clip_int16(sampledat);
01193                     prev[ch][1] = prev[ch][0];
01194                     prev[ch][0] = *samples++;
01195 
01196                     /* In case of stereo, skip one sample, this sample
01197                        is for the other channel.  */
01198                     samples += st;
01199                 }
01200             }
01201         }
01202         break;
01203     }
01204 
01205     default:
01206         return -1;
01207     }
01208 
01209     *got_frame_ptr   = 1;
01210     *(AVFrame *)data = c->frame;
01211 
01212     return src - buf;
01213 }
01214 
01215 
01216 #define ADPCM_DECODER(id_, name_, long_name_)               \
01217 AVCodec ff_ ## name_ ## _decoder = {                        \
01218     .name           = #name_,                               \
01219     .type           = AVMEDIA_TYPE_AUDIO,                   \
01220     .id             = id_,                                  \
01221     .priv_data_size = sizeof(ADPCMDecodeContext),           \
01222     .init           = adpcm_decode_init,                    \
01223     .decode         = adpcm_decode_frame,                   \
01224     .capabilities   = CODEC_CAP_DR1,                        \
01225     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),     \
01226 }
01227 
01228 /* Note: Do not forget to add new entries to the Makefile as well. */
01229 ADPCM_DECODER(CODEC_ID_ADPCM_4XM, adpcm_4xm, "ADPCM 4X Movie");
01230 ADPCM_DECODER(CODEC_ID_ADPCM_CT, adpcm_ct, "ADPCM Creative Technology");
01231 ADPCM_DECODER(CODEC_ID_ADPCM_EA, adpcm_ea, "ADPCM Electronic Arts");
01232 ADPCM_DECODER(CODEC_ID_ADPCM_EA_MAXIS_XA, adpcm_ea_maxis_xa, "ADPCM Electronic Arts Maxis CDROM XA");
01233 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R1, adpcm_ea_r1, "ADPCM Electronic Arts R1");
01234 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R2, adpcm_ea_r2, "ADPCM Electronic Arts R2");
01235 ADPCM_DECODER(CODEC_ID_ADPCM_EA_R3, adpcm_ea_r3, "ADPCM Electronic Arts R3");
01236 ADPCM_DECODER(CODEC_ID_ADPCM_EA_XAS, adpcm_ea_xas, "ADPCM Electronic Arts XAS");
01237 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_AMV, adpcm_ima_amv, "ADPCM IMA AMV");
01238 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3, "ADPCM IMA Duck DK3");
01239 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4, "ADPCM IMA Duck DK4");
01240 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_EACS, adpcm_ima_ea_eacs, "ADPCM IMA Electronic Arts EACS");
01241 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_EA_SEAD, adpcm_ima_ea_sead, "ADPCM IMA Electronic Arts SEAD");
01242 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_ISS, adpcm_ima_iss, "ADPCM IMA Funcom ISS");
01243 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt, "ADPCM IMA QuickTime");
01244 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_SMJPEG, adpcm_ima_smjpeg, "ADPCM IMA Loki SDL MJPEG");
01245 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav, "ADPCM IMA WAV");
01246 ADPCM_DECODER(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws, "ADPCM IMA Westwood");
01247 ADPCM_DECODER(CODEC_ID_ADPCM_MS, adpcm_ms, "ADPCM Microsoft");
01248 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_2, adpcm_sbpro_2, "ADPCM Sound Blaster Pro 2-bit");
01249 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_3, adpcm_sbpro_3, "ADPCM Sound Blaster Pro 2.6-bit");
01250 ADPCM_DECODER(CODEC_ID_ADPCM_SBPRO_4, adpcm_sbpro_4, "ADPCM Sound Blaster Pro 4-bit");
01251 ADPCM_DECODER(CODEC_ID_ADPCM_SWF, adpcm_swf, "ADPCM Shockwave Flash");
01252 ADPCM_DECODER(CODEC_ID_ADPCM_THP, adpcm_thp, "ADPCM Nintendo Gamecube THP");
01253 ADPCM_DECODER(CODEC_ID_ADPCM_XA, adpcm_xa, "ADPCM CDROM XA");
01254 ADPCM_DECODER(CODEC_ID_ADPCM_YAMAHA, adpcm_yamaha, "ADPCM Yamaha");