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00023 #define BITSTREAM_READER_LE
00024 #include "avcodec.h"
00025 #include "dsputil.h"
00026 #include "get_bits.h"
00027 #include "bytestream.h"
00028 #include "libavutil/audioconvert.h"
00029 #include "libavutil/avassert.h"
00030
00036 #define BLOCKS_PER_LOOP 4608
00037 #define MAX_CHANNELS 2
00038 #define MAX_BYTESPERSAMPLE 3
00039
00040 #define APE_FRAMECODE_MONO_SILENCE 1
00041 #define APE_FRAMECODE_STEREO_SILENCE 3
00042 #define APE_FRAMECODE_PSEUDO_STEREO 4
00043
00044 #define HISTORY_SIZE 512
00045 #define PREDICTOR_ORDER 8
00046
00047 #define PREDICTOR_SIZE 50
00048
00049 #define YDELAYA (18 + PREDICTOR_ORDER*4)
00050 #define YDELAYB (18 + PREDICTOR_ORDER*3)
00051 #define XDELAYA (18 + PREDICTOR_ORDER*2)
00052 #define XDELAYB (18 + PREDICTOR_ORDER)
00053
00054 #define YADAPTCOEFFSA 18
00055 #define XADAPTCOEFFSA 14
00056 #define YADAPTCOEFFSB 10
00057 #define XADAPTCOEFFSB 5
00058
00063 enum APECompressionLevel {
00064 COMPRESSION_LEVEL_FAST = 1000,
00065 COMPRESSION_LEVEL_NORMAL = 2000,
00066 COMPRESSION_LEVEL_HIGH = 3000,
00067 COMPRESSION_LEVEL_EXTRA_HIGH = 4000,
00068 COMPRESSION_LEVEL_INSANE = 5000
00069 };
00072 #define APE_FILTER_LEVELS 3
00073
00075 static const uint16_t ape_filter_orders[5][APE_FILTER_LEVELS] = {
00076 { 0, 0, 0 },
00077 { 16, 0, 0 },
00078 { 64, 0, 0 },
00079 { 32, 256, 0 },
00080 { 16, 256, 1280 }
00081 };
00082
00084 static const uint8_t ape_filter_fracbits[5][APE_FILTER_LEVELS] = {
00085 { 0, 0, 0 },
00086 { 11, 0, 0 },
00087 { 11, 0, 0 },
00088 { 10, 13, 0 },
00089 { 11, 13, 15 }
00090 };
00091
00092
00094 typedef struct APEFilter {
00095 int16_t *coeffs;
00096 int16_t *adaptcoeffs;
00097 int16_t *historybuffer;
00098 int16_t *delay;
00099
00100 int avg;
00101 } APEFilter;
00102
00103 typedef struct APERice {
00104 uint32_t k;
00105 uint32_t ksum;
00106 } APERice;
00107
00108 typedef struct APERangecoder {
00109 uint32_t low;
00110 uint32_t range;
00111 uint32_t help;
00112 unsigned int buffer;
00113 } APERangecoder;
00114
00116 typedef struct APEPredictor {
00117 int32_t *buf;
00118
00119 int32_t lastA[2];
00120
00121 int32_t filterA[2];
00122 int32_t filterB[2];
00123
00124 int32_t coeffsA[2][4];
00125 int32_t coeffsB[2][5];
00126 int32_t historybuffer[HISTORY_SIZE + PREDICTOR_SIZE];
00127 } APEPredictor;
00128
00130 typedef struct APEContext {
00131 AVCodecContext *avctx;
00132 AVFrame frame;
00133 DSPContext dsp;
00134 int channels;
00135 int samples;
00136
00137 int fileversion;
00138 int compression_level;
00139 int fset;
00140 int flags;
00141
00142 uint32_t CRC;
00143 int frameflags;
00144 APEPredictor predictor;
00145
00146 int32_t decoded0[BLOCKS_PER_LOOP];
00147 int32_t decoded1[BLOCKS_PER_LOOP];
00148
00149 int16_t* filterbuf[APE_FILTER_LEVELS];
00150
00151 APERangecoder rc;
00152 APERice riceX;
00153 APERice riceY;
00154 APEFilter filters[APE_FILTER_LEVELS][2];
00155
00156 uint8_t *data;
00157 uint8_t *data_end;
00158 const uint8_t *ptr;
00159
00160 int error;
00161 } APEContext;
00162
00163
00164
00165 static av_cold int ape_decode_close(AVCodecContext *avctx)
00166 {
00167 APEContext *s = avctx->priv_data;
00168 int i;
00169
00170 for (i = 0; i < APE_FILTER_LEVELS; i++)
00171 av_freep(&s->filterbuf[i]);
00172
00173 av_freep(&s->data);
00174 return 0;
00175 }
00176
00177 static av_cold int ape_decode_init(AVCodecContext *avctx)
00178 {
00179 APEContext *s = avctx->priv_data;
00180 int i;
00181
00182 if (avctx->extradata_size != 6) {
00183 av_log(avctx, AV_LOG_ERROR, "Incorrect extradata\n");
00184 return AVERROR(EINVAL);
00185 }
00186 if (avctx->bits_per_coded_sample != 16) {
00187 av_log(avctx, AV_LOG_ERROR, "Only 16-bit samples are supported\n");
00188 return AVERROR(EINVAL);
00189 }
00190 if (avctx->channels > 2) {
00191 av_log(avctx, AV_LOG_ERROR, "Only mono and stereo is supported\n");
00192 return AVERROR(EINVAL);
00193 }
00194 s->avctx = avctx;
00195 s->channels = avctx->channels;
00196 s->fileversion = AV_RL16(avctx->extradata);
00197 s->compression_level = AV_RL16(avctx->extradata + 2);
00198 s->flags = AV_RL16(avctx->extradata + 4);
00199
00200 av_log(avctx, AV_LOG_DEBUG, "Compression Level: %d - Flags: %d\n",
00201 s->compression_level, s->flags);
00202 if (s->compression_level % 1000 || s->compression_level > COMPRESSION_LEVEL_INSANE) {
00203 av_log(avctx, AV_LOG_ERROR, "Incorrect compression level %d\n",
00204 s->compression_level);
00205 return AVERROR_INVALIDDATA;
00206 }
00207 s->fset = s->compression_level / 1000 - 1;
00208 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00209 if (!ape_filter_orders[s->fset][i])
00210 break;
00211 FF_ALLOC_OR_GOTO(avctx, s->filterbuf[i],
00212 (ape_filter_orders[s->fset][i] * 3 + HISTORY_SIZE) * 4,
00213 filter_alloc_fail);
00214 }
00215
00216 dsputil_init(&s->dsp, avctx);
00217 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00218 avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
00219
00220 avcodec_get_frame_defaults(&s->frame);
00221 avctx->coded_frame = &s->frame;
00222
00223 return 0;
00224 filter_alloc_fail:
00225 ape_decode_close(avctx);
00226 return AVERROR(ENOMEM);
00227 }
00228
00234 #define CODE_BITS 32
00235 #define TOP_VALUE ((unsigned int)1 << (CODE_BITS-1))
00236 #define SHIFT_BITS (CODE_BITS - 9)
00237 #define EXTRA_BITS ((CODE_BITS-2) % 8 + 1)
00238 #define BOTTOM_VALUE (TOP_VALUE >> 8)
00239
00241 static inline void range_start_decoding(APEContext *ctx)
00242 {
00243 ctx->rc.buffer = bytestream_get_byte(&ctx->ptr);
00244 ctx->rc.low = ctx->rc.buffer >> (8 - EXTRA_BITS);
00245 ctx->rc.range = (uint32_t) 1 << EXTRA_BITS;
00246 }
00247
00249 static inline void range_dec_normalize(APEContext *ctx)
00250 {
00251 while (ctx->rc.range <= BOTTOM_VALUE) {
00252 ctx->rc.buffer <<= 8;
00253 if(ctx->ptr < ctx->data_end) {
00254 ctx->rc.buffer += *ctx->ptr;
00255 ctx->ptr++;
00256 } else {
00257 ctx->error = 1;
00258 }
00259 ctx->rc.low = (ctx->rc.low << 8) | ((ctx->rc.buffer >> 1) & 0xFF);
00260 ctx->rc.range <<= 8;
00261 }
00262 }
00263
00270 static inline int range_decode_culfreq(APEContext *ctx, int tot_f)
00271 {
00272 range_dec_normalize(ctx);
00273 ctx->rc.help = ctx->rc.range / tot_f;
00274 return ctx->rc.low / ctx->rc.help;
00275 }
00276
00282 static inline int range_decode_culshift(APEContext *ctx, int shift)
00283 {
00284 range_dec_normalize(ctx);
00285 ctx->rc.help = ctx->rc.range >> shift;
00286 return ctx->rc.low / ctx->rc.help;
00287 }
00288
00289
00296 static inline void range_decode_update(APEContext *ctx, int sy_f, int lt_f)
00297 {
00298 ctx->rc.low -= ctx->rc.help * lt_f;
00299 ctx->rc.range = ctx->rc.help * sy_f;
00300 }
00301
00303 static inline int range_decode_bits(APEContext *ctx, int n)
00304 {
00305 int sym = range_decode_culshift(ctx, n);
00306 range_decode_update(ctx, 1, sym);
00307 return sym;
00308 }
00309
00310
00311 #define MODEL_ELEMENTS 64
00312
00316 static const uint16_t counts_3970[22] = {
00317 0, 14824, 28224, 39348, 47855, 53994, 58171, 60926,
00318 62682, 63786, 64463, 64878, 65126, 65276, 65365, 65419,
00319 65450, 65469, 65480, 65487, 65491, 65493,
00320 };
00321
00325 static const uint16_t counts_diff_3970[21] = {
00326 14824, 13400, 11124, 8507, 6139, 4177, 2755, 1756,
00327 1104, 677, 415, 248, 150, 89, 54, 31,
00328 19, 11, 7, 4, 2,
00329 };
00330
00334 static const uint16_t counts_3980[22] = {
00335 0, 19578, 36160, 48417, 56323, 60899, 63265, 64435,
00336 64971, 65232, 65351, 65416, 65447, 65466, 65476, 65482,
00337 65485, 65488, 65490, 65491, 65492, 65493,
00338 };
00339
00343 static const uint16_t counts_diff_3980[21] = {
00344 19578, 16582, 12257, 7906, 4576, 2366, 1170, 536,
00345 261, 119, 65, 31, 19, 10, 6, 3,
00346 3, 2, 1, 1, 1,
00347 };
00348
00355 static inline int range_get_symbol(APEContext *ctx,
00356 const uint16_t counts[],
00357 const uint16_t counts_diff[])
00358 {
00359 int symbol, cf;
00360
00361 cf = range_decode_culshift(ctx, 16);
00362
00363 if(cf > 65492){
00364 symbol= cf - 65535 + 63;
00365 range_decode_update(ctx, 1, cf);
00366 if(cf > 65535)
00367 ctx->error=1;
00368 return symbol;
00369 }
00370
00371 for (symbol = 0; counts[symbol + 1] <= cf; symbol++);
00372
00373 range_decode_update(ctx, counts_diff[symbol], counts[symbol]);
00374
00375 return symbol;
00376 }
00378
00379 static inline void update_rice(APERice *rice, int x)
00380 {
00381 int lim = rice->k ? (1 << (rice->k + 4)) : 0;
00382 rice->ksum += ((x + 1) / 2) - ((rice->ksum + 16) >> 5);
00383
00384 if (rice->ksum < lim)
00385 rice->k--;
00386 else if (rice->ksum >= (1 << (rice->k + 5)))
00387 rice->k++;
00388 }
00389
00390 static inline int ape_decode_value(APEContext *ctx, APERice *rice)
00391 {
00392 int x, overflow;
00393
00394 if (ctx->fileversion < 3990) {
00395 int tmpk;
00396
00397 overflow = range_get_symbol(ctx, counts_3970, counts_diff_3970);
00398
00399 if (overflow == (MODEL_ELEMENTS - 1)) {
00400 tmpk = range_decode_bits(ctx, 5);
00401 overflow = 0;
00402 } else
00403 tmpk = (rice->k < 1) ? 0 : rice->k - 1;
00404
00405 if (tmpk <= 16)
00406 x = range_decode_bits(ctx, tmpk);
00407 else if (tmpk <= 32) {
00408 x = range_decode_bits(ctx, 16);
00409 x |= (range_decode_bits(ctx, tmpk - 16) << 16);
00410 } else {
00411 av_log(ctx->avctx, AV_LOG_ERROR, "Too many bits: %d\n", tmpk);
00412 return AVERROR_INVALIDDATA;
00413 }
00414 x += overflow << tmpk;
00415 } else {
00416 int base, pivot;
00417
00418 pivot = rice->ksum >> 5;
00419 if (pivot == 0)
00420 pivot = 1;
00421
00422 overflow = range_get_symbol(ctx, counts_3980, counts_diff_3980);
00423
00424 if (overflow == (MODEL_ELEMENTS - 1)) {
00425 overflow = range_decode_bits(ctx, 16) << 16;
00426 overflow |= range_decode_bits(ctx, 16);
00427 }
00428
00429 if (pivot < 0x10000) {
00430 base = range_decode_culfreq(ctx, pivot);
00431 range_decode_update(ctx, 1, base);
00432 } else {
00433 int base_hi = pivot, base_lo;
00434 int bbits = 0;
00435
00436 while (base_hi & ~0xFFFF) {
00437 base_hi >>= 1;
00438 bbits++;
00439 }
00440 base_hi = range_decode_culfreq(ctx, base_hi + 1);
00441 range_decode_update(ctx, 1, base_hi);
00442 base_lo = range_decode_culfreq(ctx, 1 << bbits);
00443 range_decode_update(ctx, 1, base_lo);
00444
00445 base = (base_hi << bbits) + base_lo;
00446 }
00447
00448 x = base + overflow * pivot;
00449 }
00450
00451 update_rice(rice, x);
00452
00453
00454 if (x & 1)
00455 return (x >> 1) + 1;
00456 else
00457 return -(x >> 1);
00458 }
00459
00460 static void entropy_decode(APEContext *ctx, int blockstodecode, int stereo)
00461 {
00462 int32_t *decoded0 = ctx->decoded0;
00463 int32_t *decoded1 = ctx->decoded1;
00464
00465 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00466
00467 memset(decoded0, 0, blockstodecode * sizeof(int32_t));
00468 memset(decoded1, 0, blockstodecode * sizeof(int32_t));
00469 } else {
00470 while (blockstodecode--) {
00471 *decoded0++ = ape_decode_value(ctx, &ctx->riceY);
00472 if (stereo)
00473 *decoded1++ = ape_decode_value(ctx, &ctx->riceX);
00474 }
00475 }
00476 }
00477
00478 static int init_entropy_decoder(APEContext *ctx)
00479 {
00480
00481 if (ctx->data_end - ctx->ptr < 6)
00482 return AVERROR_INVALIDDATA;
00483 ctx->CRC = bytestream_get_be32(&ctx->ptr);
00484
00485
00486 ctx->frameflags = 0;
00487 if ((ctx->fileversion > 3820) && (ctx->CRC & 0x80000000)) {
00488 ctx->CRC &= ~0x80000000;
00489
00490 if (ctx->data_end - ctx->ptr < 6)
00491 return AVERROR_INVALIDDATA;
00492 ctx->frameflags = bytestream_get_be32(&ctx->ptr);
00493 }
00494
00495
00496 ctx->riceX.k = 10;
00497 ctx->riceX.ksum = (1 << ctx->riceX.k) * 16;
00498 ctx->riceY.k = 10;
00499 ctx->riceY.ksum = (1 << ctx->riceY.k) * 16;
00500
00501
00502 ctx->ptr++;
00503
00504 range_start_decoding(ctx);
00505
00506 return 0;
00507 }
00508
00509 static const int32_t initial_coeffs[4] = {
00510 360, 317, -109, 98
00511 };
00512
00513 static void init_predictor_decoder(APEContext *ctx)
00514 {
00515 APEPredictor *p = &ctx->predictor;
00516
00517
00518 memset(p->historybuffer, 0, PREDICTOR_SIZE * sizeof(int32_t));
00519 p->buf = p->historybuffer;
00520
00521
00522 memcpy(p->coeffsA[0], initial_coeffs, sizeof(initial_coeffs));
00523 memcpy(p->coeffsA[1], initial_coeffs, sizeof(initial_coeffs));
00524 memset(p->coeffsB, 0, sizeof(p->coeffsB));
00525
00526 p->filterA[0] = p->filterA[1] = 0;
00527 p->filterB[0] = p->filterB[1] = 0;
00528 p->lastA[0] = p->lastA[1] = 0;
00529 }
00530
00532 static inline int APESIGN(int32_t x) {
00533 return (x < 0) - (x > 0);
00534 }
00535
00536 static av_always_inline int predictor_update_filter(APEPredictor *p,
00537 const int decoded, const int filter,
00538 const int delayA, const int delayB,
00539 const int adaptA, const int adaptB)
00540 {
00541 int32_t predictionA, predictionB, sign;
00542
00543 p->buf[delayA] = p->lastA[filter];
00544 p->buf[adaptA] = APESIGN(p->buf[delayA]);
00545 p->buf[delayA - 1] = p->buf[delayA] - p->buf[delayA - 1];
00546 p->buf[adaptA - 1] = APESIGN(p->buf[delayA - 1]);
00547
00548 predictionA = p->buf[delayA ] * p->coeffsA[filter][0] +
00549 p->buf[delayA - 1] * p->coeffsA[filter][1] +
00550 p->buf[delayA - 2] * p->coeffsA[filter][2] +
00551 p->buf[delayA - 3] * p->coeffsA[filter][3];
00552
00553
00554 p->buf[delayB] = p->filterA[filter ^ 1] - ((p->filterB[filter] * 31) >> 5);
00555 p->buf[adaptB] = APESIGN(p->buf[delayB]);
00556 p->buf[delayB - 1] = p->buf[delayB] - p->buf[delayB - 1];
00557 p->buf[adaptB - 1] = APESIGN(p->buf[delayB - 1]);
00558 p->filterB[filter] = p->filterA[filter ^ 1];
00559
00560 predictionB = p->buf[delayB ] * p->coeffsB[filter][0] +
00561 p->buf[delayB - 1] * p->coeffsB[filter][1] +
00562 p->buf[delayB - 2] * p->coeffsB[filter][2] +
00563 p->buf[delayB - 3] * p->coeffsB[filter][3] +
00564 p->buf[delayB - 4] * p->coeffsB[filter][4];
00565
00566 p->lastA[filter] = decoded + ((predictionA + (predictionB >> 1)) >> 10);
00567 p->filterA[filter] = p->lastA[filter] + ((p->filterA[filter] * 31) >> 5);
00568
00569 sign = APESIGN(decoded);
00570 p->coeffsA[filter][0] += p->buf[adaptA ] * sign;
00571 p->coeffsA[filter][1] += p->buf[adaptA - 1] * sign;
00572 p->coeffsA[filter][2] += p->buf[adaptA - 2] * sign;
00573 p->coeffsA[filter][3] += p->buf[adaptA - 3] * sign;
00574 p->coeffsB[filter][0] += p->buf[adaptB ] * sign;
00575 p->coeffsB[filter][1] += p->buf[adaptB - 1] * sign;
00576 p->coeffsB[filter][2] += p->buf[adaptB - 2] * sign;
00577 p->coeffsB[filter][3] += p->buf[adaptB - 3] * sign;
00578 p->coeffsB[filter][4] += p->buf[adaptB - 4] * sign;
00579
00580 return p->filterA[filter];
00581 }
00582
00583 static void predictor_decode_stereo(APEContext *ctx, int count)
00584 {
00585 APEPredictor *p = &ctx->predictor;
00586 int32_t *decoded0 = ctx->decoded0;
00587 int32_t *decoded1 = ctx->decoded1;
00588
00589 while (count--) {
00590
00591 *decoded0 = predictor_update_filter(p, *decoded0, 0, YDELAYA, YDELAYB,
00592 YADAPTCOEFFSA, YADAPTCOEFFSB);
00593 decoded0++;
00594 *decoded1 = predictor_update_filter(p, *decoded1, 1, XDELAYA, XDELAYB,
00595 XADAPTCOEFFSA, XADAPTCOEFFSB);
00596 decoded1++;
00597
00598
00599 p->buf++;
00600
00601
00602 if (p->buf == p->historybuffer + HISTORY_SIZE) {
00603 memmove(p->historybuffer, p->buf, PREDICTOR_SIZE * sizeof(int32_t));
00604 p->buf = p->historybuffer;
00605 }
00606 }
00607 }
00608
00609 static void predictor_decode_mono(APEContext *ctx, int count)
00610 {
00611 APEPredictor *p = &ctx->predictor;
00612 int32_t *decoded0 = ctx->decoded0;
00613 int32_t predictionA, currentA, A, sign;
00614
00615 currentA = p->lastA[0];
00616
00617 while (count--) {
00618 A = *decoded0;
00619
00620 p->buf[YDELAYA] = currentA;
00621 p->buf[YDELAYA - 1] = p->buf[YDELAYA] - p->buf[YDELAYA - 1];
00622
00623 predictionA = p->buf[YDELAYA ] * p->coeffsA[0][0] +
00624 p->buf[YDELAYA - 1] * p->coeffsA[0][1] +
00625 p->buf[YDELAYA - 2] * p->coeffsA[0][2] +
00626 p->buf[YDELAYA - 3] * p->coeffsA[0][3];
00627
00628 currentA = A + (predictionA >> 10);
00629
00630 p->buf[YADAPTCOEFFSA] = APESIGN(p->buf[YDELAYA ]);
00631 p->buf[YADAPTCOEFFSA - 1] = APESIGN(p->buf[YDELAYA - 1]);
00632
00633 sign = APESIGN(A);
00634 p->coeffsA[0][0] += p->buf[YADAPTCOEFFSA ] * sign;
00635 p->coeffsA[0][1] += p->buf[YADAPTCOEFFSA - 1] * sign;
00636 p->coeffsA[0][2] += p->buf[YADAPTCOEFFSA - 2] * sign;
00637 p->coeffsA[0][3] += p->buf[YADAPTCOEFFSA - 3] * sign;
00638
00639 p->buf++;
00640
00641
00642 if (p->buf == p->historybuffer + HISTORY_SIZE) {
00643 memmove(p->historybuffer, p->buf, PREDICTOR_SIZE * sizeof(int32_t));
00644 p->buf = p->historybuffer;
00645 }
00646
00647 p->filterA[0] = currentA + ((p->filterA[0] * 31) >> 5);
00648 *(decoded0++) = p->filterA[0];
00649 }
00650
00651 p->lastA[0] = currentA;
00652 }
00653
00654 static void do_init_filter(APEFilter *f, int16_t *buf, int order)
00655 {
00656 f->coeffs = buf;
00657 f->historybuffer = buf + order;
00658 f->delay = f->historybuffer + order * 2;
00659 f->adaptcoeffs = f->historybuffer + order;
00660
00661 memset(f->historybuffer, 0, (order * 2) * sizeof(int16_t));
00662 memset(f->coeffs, 0, order * sizeof(int16_t));
00663 f->avg = 0;
00664 }
00665
00666 static void init_filter(APEContext *ctx, APEFilter *f, int16_t *buf, int order)
00667 {
00668 do_init_filter(&f[0], buf, order);
00669 do_init_filter(&f[1], buf + order * 3 + HISTORY_SIZE, order);
00670 }
00671
00672 static void do_apply_filter(APEContext *ctx, int version, APEFilter *f,
00673 int32_t *data, int count, int order, int fracbits)
00674 {
00675 int res;
00676 int absres;
00677
00678 while (count--) {
00679
00680 res = ctx->dsp.scalarproduct_and_madd_int16(f->coeffs, f->delay - order,
00681 f->adaptcoeffs - order,
00682 order, APESIGN(*data));
00683 res = (res + (1 << (fracbits - 1))) >> fracbits;
00684 res += *data;
00685 *data++ = res;
00686
00687
00688 *f->delay++ = av_clip_int16(res);
00689
00690 if (version < 3980) {
00691
00692 f->adaptcoeffs[0] = (res == 0) ? 0 : ((res >> 28) & 8) - 4;
00693 f->adaptcoeffs[-4] >>= 1;
00694 f->adaptcoeffs[-8] >>= 1;
00695 } else {
00696
00697
00698
00699 absres = FFABS(res);
00700 if (absres)
00701 *f->adaptcoeffs = ((res & (-1<<31)) ^ (-1<<30)) >>
00702 (25 + (absres <= f->avg*3) + (absres <= f->avg*4/3));
00703 else
00704 *f->adaptcoeffs = 0;
00705
00706 f->avg += (absres - f->avg) / 16;
00707
00708 f->adaptcoeffs[-1] >>= 1;
00709 f->adaptcoeffs[-2] >>= 1;
00710 f->adaptcoeffs[-8] >>= 1;
00711 }
00712
00713 f->adaptcoeffs++;
00714
00715
00716 if (f->delay == f->historybuffer + HISTORY_SIZE + (order * 2)) {
00717 memmove(f->historybuffer, f->delay - (order * 2),
00718 (order * 2) * sizeof(int16_t));
00719 f->delay = f->historybuffer + order * 2;
00720 f->adaptcoeffs = f->historybuffer + order;
00721 }
00722 }
00723 }
00724
00725 static void apply_filter(APEContext *ctx, APEFilter *f,
00726 int32_t *data0, int32_t *data1,
00727 int count, int order, int fracbits)
00728 {
00729 do_apply_filter(ctx, ctx->fileversion, &f[0], data0, count, order, fracbits);
00730 if (data1)
00731 do_apply_filter(ctx, ctx->fileversion, &f[1], data1, count, order, fracbits);
00732 }
00733
00734 static void ape_apply_filters(APEContext *ctx, int32_t *decoded0,
00735 int32_t *decoded1, int count)
00736 {
00737 int i;
00738
00739 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00740 if (!ape_filter_orders[ctx->fset][i])
00741 break;
00742 apply_filter(ctx, ctx->filters[i], decoded0, decoded1, count,
00743 ape_filter_orders[ctx->fset][i],
00744 ape_filter_fracbits[ctx->fset][i]);
00745 }
00746 }
00747
00748 static int init_frame_decoder(APEContext *ctx)
00749 {
00750 int i, ret;
00751 if ((ret = init_entropy_decoder(ctx)) < 0)
00752 return ret;
00753 init_predictor_decoder(ctx);
00754
00755 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00756 if (!ape_filter_orders[ctx->fset][i])
00757 break;
00758 init_filter(ctx, ctx->filters[i], ctx->filterbuf[i],
00759 ape_filter_orders[ctx->fset][i]);
00760 }
00761 return 0;
00762 }
00763
00764 static void ape_unpack_mono(APEContext *ctx, int count)
00765 {
00766 int32_t *decoded0 = ctx->decoded0;
00767 int32_t *decoded1 = ctx->decoded1;
00768
00769 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00770 entropy_decode(ctx, count, 0);
00771
00772 av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence mono\n");
00773 return;
00774 }
00775
00776 entropy_decode(ctx, count, 0);
00777 ape_apply_filters(ctx, decoded0, NULL, count);
00778
00779
00780 predictor_decode_mono(ctx, count);
00781
00782
00783 if (ctx->channels == 2) {
00784 memcpy(decoded1, decoded0, count * sizeof(*decoded1));
00785 }
00786 }
00787
00788 static void ape_unpack_stereo(APEContext *ctx, int count)
00789 {
00790 int32_t left, right;
00791 int32_t *decoded0 = ctx->decoded0;
00792 int32_t *decoded1 = ctx->decoded1;
00793
00794 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00795
00796 av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence stereo\n");
00797 return;
00798 }
00799
00800 entropy_decode(ctx, count, 1);
00801 ape_apply_filters(ctx, decoded0, decoded1, count);
00802
00803
00804 predictor_decode_stereo(ctx, count);
00805
00806
00807 while (count--) {
00808 left = *decoded1 - (*decoded0 / 2);
00809 right = left + *decoded0;
00810
00811 *(decoded0++) = left;
00812 *(decoded1++) = right;
00813 }
00814 }
00815
00816 static int ape_decode_frame(AVCodecContext *avctx, void *data,
00817 int *got_frame_ptr, AVPacket *avpkt)
00818 {
00819 const uint8_t *buf = avpkt->data;
00820 int buf_size = avpkt->size;
00821 APEContext *s = avctx->priv_data;
00822 int16_t *samples;
00823 int i, ret;
00824 int blockstodecode;
00825 int bytes_used = 0;
00826
00827
00828
00829 av_assert0(s->samples >= 0);
00830
00831 if(!s->samples){
00832 uint32_t nblocks, offset;
00833 void *tmp_data;
00834
00835 if (!buf_size) {
00836 *got_frame_ptr = 0;
00837 return 0;
00838 }
00839 if (buf_size < 8) {
00840 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
00841 return AVERROR_INVALIDDATA;
00842 }
00843
00844 tmp_data = av_realloc(s->data, FFALIGN(buf_size, 4));
00845 if (!tmp_data)
00846 return AVERROR(ENOMEM);
00847 s->data = tmp_data;
00848 s->dsp.bswap_buf((uint32_t*)s->data, (const uint32_t*)buf, buf_size >> 2);
00849 s->ptr = s->data;
00850 s->data_end = s->data + buf_size;
00851
00852 nblocks = bytestream_get_be32(&s->ptr);
00853 offset = bytestream_get_be32(&s->ptr);
00854 if (offset > 3) {
00855 av_log(avctx, AV_LOG_ERROR, "Incorrect offset passed\n");
00856 s->data = NULL;
00857 return AVERROR_INVALIDDATA;
00858 }
00859 if (s->data_end - s->ptr < offset) {
00860 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
00861 return AVERROR_INVALIDDATA;
00862 }
00863 s->ptr += offset;
00864
00865 if (!nblocks || nblocks > INT_MAX) {
00866 av_log(avctx, AV_LOG_ERROR, "Invalid sample count: %u.\n", nblocks);
00867 return AVERROR_INVALIDDATA;
00868 }
00869 s->samples = nblocks;
00870
00871 memset(s->decoded0, 0, sizeof(s->decoded0));
00872 memset(s->decoded1, 0, sizeof(s->decoded1));
00873
00874
00875 if (init_frame_decoder(s) < 0) {
00876 av_log(avctx, AV_LOG_ERROR, "Error reading frame header\n");
00877 return AVERROR_INVALIDDATA;
00878 }
00879
00880 bytes_used = buf_size;
00881 }
00882
00883 if (!s->data) {
00884 *got_frame_ptr = 0;
00885 return buf_size;
00886 }
00887
00888 blockstodecode = FFMIN(BLOCKS_PER_LOOP, s->samples);
00889
00890
00891 s->frame.nb_samples = blockstodecode;
00892 if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
00893 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00894 return ret;
00895 }
00896 samples = (int16_t *)s->frame.data[0];
00897
00898 s->error=0;
00899
00900 if ((s->channels == 1) || (s->frameflags & APE_FRAMECODE_PSEUDO_STEREO))
00901 ape_unpack_mono(s, blockstodecode);
00902 else
00903 ape_unpack_stereo(s, blockstodecode);
00904 emms_c();
00905
00906 if (s->error) {
00907 s->samples=0;
00908 av_log(avctx, AV_LOG_ERROR, "Error decoding frame\n");
00909 return AVERROR_INVALIDDATA;
00910 }
00911
00912 for (i = 0; i < blockstodecode; i++) {
00913 *samples++ = s->decoded0[i];
00914 if(s->channels == 2)
00915 *samples++ = s->decoded1[i];
00916 }
00917
00918 s->samples -= blockstodecode;
00919
00920 *got_frame_ptr = 1;
00921 *(AVFrame *)data = s->frame;
00922
00923 return bytes_used;
00924 }
00925
00926 static void ape_flush(AVCodecContext *avctx)
00927 {
00928 APEContext *s = avctx->priv_data;
00929 s->samples= 0;
00930 }
00931
00932 AVCodec ff_ape_decoder = {
00933 .name = "ape",
00934 .type = AVMEDIA_TYPE_AUDIO,
00935 .id = CODEC_ID_APE,
00936 .priv_data_size = sizeof(APEContext),
00937 .init = ape_decode_init,
00938 .close = ape_decode_close,
00939 .decode = ape_decode_frame,
00940 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DELAY | CODEC_CAP_DR1,
00941 .flush = ape_flush,
00942 .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
00943 };