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00023 #define BITSTREAM_READER_LE
00024 #include "avcodec.h"
00025 #include "internal.h"
00026 #include "dsputil.h"
00027 #include "get_bits.h"
00028 #include "bytestream.h"
00029 #include "libavutil/audioconvert.h"
00030 #include "libavutil/avassert.h"
00031
00037 #define BLOCKS_PER_LOOP 4608
00038 #define MAX_CHANNELS 2
00039 #define MAX_BYTESPERSAMPLE 3
00040
00041 #define APE_FRAMECODE_MONO_SILENCE 1
00042 #define APE_FRAMECODE_STEREO_SILENCE 3
00043 #define APE_FRAMECODE_PSEUDO_STEREO 4
00044
00045 #define HISTORY_SIZE 512
00046 #define PREDICTOR_ORDER 8
00047
00048 #define PREDICTOR_SIZE 50
00049
00050 #define YDELAYA (18 + PREDICTOR_ORDER*4)
00051 #define YDELAYB (18 + PREDICTOR_ORDER*3)
00052 #define XDELAYA (18 + PREDICTOR_ORDER*2)
00053 #define XDELAYB (18 + PREDICTOR_ORDER)
00054
00055 #define YADAPTCOEFFSA 18
00056 #define XADAPTCOEFFSA 14
00057 #define YADAPTCOEFFSB 10
00058 #define XADAPTCOEFFSB 5
00059
00064 enum APECompressionLevel {
00065 COMPRESSION_LEVEL_FAST = 1000,
00066 COMPRESSION_LEVEL_NORMAL = 2000,
00067 COMPRESSION_LEVEL_HIGH = 3000,
00068 COMPRESSION_LEVEL_EXTRA_HIGH = 4000,
00069 COMPRESSION_LEVEL_INSANE = 5000
00070 };
00073 #define APE_FILTER_LEVELS 3
00074
00076 static const uint16_t ape_filter_orders[5][APE_FILTER_LEVELS] = {
00077 { 0, 0, 0 },
00078 { 16, 0, 0 },
00079 { 64, 0, 0 },
00080 { 32, 256, 0 },
00081 { 16, 256, 1280 }
00082 };
00083
00085 static const uint8_t ape_filter_fracbits[5][APE_FILTER_LEVELS] = {
00086 { 0, 0, 0 },
00087 { 11, 0, 0 },
00088 { 11, 0, 0 },
00089 { 10, 13, 0 },
00090 { 11, 13, 15 }
00091 };
00092
00093
00095 typedef struct APEFilter {
00096 int16_t *coeffs;
00097 int16_t *adaptcoeffs;
00098 int16_t *historybuffer;
00099 int16_t *delay;
00100
00101 int avg;
00102 } APEFilter;
00103
00104 typedef struct APERice {
00105 uint32_t k;
00106 uint32_t ksum;
00107 } APERice;
00108
00109 typedef struct APERangecoder {
00110 uint32_t low;
00111 uint32_t range;
00112 uint32_t help;
00113 unsigned int buffer;
00114 } APERangecoder;
00115
00117 typedef struct APEPredictor {
00118 int32_t *buf;
00119
00120 int32_t lastA[2];
00121
00122 int32_t filterA[2];
00123 int32_t filterB[2];
00124
00125 int32_t coeffsA[2][4];
00126 int32_t coeffsB[2][5];
00127 int32_t historybuffer[HISTORY_SIZE + PREDICTOR_SIZE];
00128 } APEPredictor;
00129
00131 typedef struct APEContext {
00132 AVCodecContext *avctx;
00133 AVFrame frame;
00134 DSPContext dsp;
00135 int channels;
00136 int samples;
00137
00138 int fileversion;
00139 int compression_level;
00140 int fset;
00141 int flags;
00142
00143 uint32_t CRC;
00144 int frameflags;
00145 APEPredictor predictor;
00146
00147 int32_t decoded0[BLOCKS_PER_LOOP];
00148 int32_t decoded1[BLOCKS_PER_LOOP];
00149
00150 int16_t* filterbuf[APE_FILTER_LEVELS];
00151
00152 APERangecoder rc;
00153 APERice riceX;
00154 APERice riceY;
00155 APEFilter filters[APE_FILTER_LEVELS][2];
00156
00157 uint8_t *data;
00158 uint8_t *data_end;
00159 const uint8_t *ptr;
00160
00161 int error;
00162 } APEContext;
00163
00164
00165
00166 static av_cold int ape_decode_close(AVCodecContext *avctx)
00167 {
00168 APEContext *s = avctx->priv_data;
00169 int i;
00170
00171 for (i = 0; i < APE_FILTER_LEVELS; i++)
00172 av_freep(&s->filterbuf[i]);
00173
00174 av_freep(&s->data);
00175 return 0;
00176 }
00177
00178 static av_cold int ape_decode_init(AVCodecContext *avctx)
00179 {
00180 APEContext *s = avctx->priv_data;
00181 int i;
00182
00183 if (avctx->extradata_size != 6) {
00184 av_log(avctx, AV_LOG_ERROR, "Incorrect extradata\n");
00185 return AVERROR(EINVAL);
00186 }
00187 if (avctx->bits_per_coded_sample != 16) {
00188 av_log(avctx, AV_LOG_ERROR, "Only 16-bit samples are supported\n");
00189 return AVERROR(EINVAL);
00190 }
00191 if (avctx->channels > 2) {
00192 av_log(avctx, AV_LOG_ERROR, "Only mono and stereo is supported\n");
00193 return AVERROR(EINVAL);
00194 }
00195 s->avctx = avctx;
00196 s->channels = avctx->channels;
00197 s->fileversion = AV_RL16(avctx->extradata);
00198 s->compression_level = AV_RL16(avctx->extradata + 2);
00199 s->flags = AV_RL16(avctx->extradata + 4);
00200
00201 av_log(avctx, AV_LOG_DEBUG, "Compression Level: %d - Flags: %d\n",
00202 s->compression_level, s->flags);
00203 if (s->compression_level % 1000 || s->compression_level > COMPRESSION_LEVEL_INSANE) {
00204 av_log(avctx, AV_LOG_ERROR, "Incorrect compression level %d\n",
00205 s->compression_level);
00206 return AVERROR_INVALIDDATA;
00207 }
00208 s->fset = s->compression_level / 1000 - 1;
00209 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00210 if (!ape_filter_orders[s->fset][i])
00211 break;
00212 FF_ALLOC_OR_GOTO(avctx, s->filterbuf[i],
00213 (ape_filter_orders[s->fset][i] * 3 + HISTORY_SIZE) * 4,
00214 filter_alloc_fail);
00215 }
00216
00217 dsputil_init(&s->dsp, avctx);
00218 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00219 avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
00220
00221 avcodec_get_frame_defaults(&s->frame);
00222 avctx->coded_frame = &s->frame;
00223
00224 return 0;
00225 filter_alloc_fail:
00226 ape_decode_close(avctx);
00227 return AVERROR(ENOMEM);
00228 }
00229
00235 #define CODE_BITS 32
00236 #define TOP_VALUE ((unsigned int)1 << (CODE_BITS-1))
00237 #define SHIFT_BITS (CODE_BITS - 9)
00238 #define EXTRA_BITS ((CODE_BITS-2) % 8 + 1)
00239 #define BOTTOM_VALUE (TOP_VALUE >> 8)
00240
00242 static inline void range_start_decoding(APEContext *ctx)
00243 {
00244 ctx->rc.buffer = bytestream_get_byte(&ctx->ptr);
00245 ctx->rc.low = ctx->rc.buffer >> (8 - EXTRA_BITS);
00246 ctx->rc.range = (uint32_t) 1 << EXTRA_BITS;
00247 }
00248
00250 static inline void range_dec_normalize(APEContext *ctx)
00251 {
00252 while (ctx->rc.range <= BOTTOM_VALUE) {
00253 ctx->rc.buffer <<= 8;
00254 if(ctx->ptr < ctx->data_end) {
00255 ctx->rc.buffer += *ctx->ptr;
00256 ctx->ptr++;
00257 } else {
00258 ctx->error = 1;
00259 }
00260 ctx->rc.low = (ctx->rc.low << 8) | ((ctx->rc.buffer >> 1) & 0xFF);
00261 ctx->rc.range <<= 8;
00262 }
00263 }
00264
00271 static inline int range_decode_culfreq(APEContext *ctx, int tot_f)
00272 {
00273 range_dec_normalize(ctx);
00274 ctx->rc.help = ctx->rc.range / tot_f;
00275 return ctx->rc.low / ctx->rc.help;
00276 }
00277
00283 static inline int range_decode_culshift(APEContext *ctx, int shift)
00284 {
00285 range_dec_normalize(ctx);
00286 ctx->rc.help = ctx->rc.range >> shift;
00287 return ctx->rc.low / ctx->rc.help;
00288 }
00289
00290
00297 static inline void range_decode_update(APEContext *ctx, int sy_f, int lt_f)
00298 {
00299 ctx->rc.low -= ctx->rc.help * lt_f;
00300 ctx->rc.range = ctx->rc.help * sy_f;
00301 }
00302
00304 static inline int range_decode_bits(APEContext *ctx, int n)
00305 {
00306 int sym = range_decode_culshift(ctx, n);
00307 range_decode_update(ctx, 1, sym);
00308 return sym;
00309 }
00310
00311
00312 #define MODEL_ELEMENTS 64
00313
00317 static const uint16_t counts_3970[22] = {
00318 0, 14824, 28224, 39348, 47855, 53994, 58171, 60926,
00319 62682, 63786, 64463, 64878, 65126, 65276, 65365, 65419,
00320 65450, 65469, 65480, 65487, 65491, 65493,
00321 };
00322
00326 static const uint16_t counts_diff_3970[21] = {
00327 14824, 13400, 11124, 8507, 6139, 4177, 2755, 1756,
00328 1104, 677, 415, 248, 150, 89, 54, 31,
00329 19, 11, 7, 4, 2,
00330 };
00331
00335 static const uint16_t counts_3980[22] = {
00336 0, 19578, 36160, 48417, 56323, 60899, 63265, 64435,
00337 64971, 65232, 65351, 65416, 65447, 65466, 65476, 65482,
00338 65485, 65488, 65490, 65491, 65492, 65493,
00339 };
00340
00344 static const uint16_t counts_diff_3980[21] = {
00345 19578, 16582, 12257, 7906, 4576, 2366, 1170, 536,
00346 261, 119, 65, 31, 19, 10, 6, 3,
00347 3, 2, 1, 1, 1,
00348 };
00349
00356 static inline int range_get_symbol(APEContext *ctx,
00357 const uint16_t counts[],
00358 const uint16_t counts_diff[])
00359 {
00360 int symbol, cf;
00361
00362 cf = range_decode_culshift(ctx, 16);
00363
00364 if(cf > 65492){
00365 symbol= cf - 65535 + 63;
00366 range_decode_update(ctx, 1, cf);
00367 if(cf > 65535)
00368 ctx->error=1;
00369 return symbol;
00370 }
00371
00372 for (symbol = 0; counts[symbol + 1] <= cf; symbol++);
00373
00374 range_decode_update(ctx, counts_diff[symbol], counts[symbol]);
00375
00376 return symbol;
00377 }
00379
00380 static inline void update_rice(APERice *rice, int x)
00381 {
00382 int lim = rice->k ? (1 << (rice->k + 4)) : 0;
00383 rice->ksum += ((x + 1) / 2) - ((rice->ksum + 16) >> 5);
00384
00385 if (rice->ksum < lim)
00386 rice->k--;
00387 else if (rice->ksum >= (1 << (rice->k + 5)))
00388 rice->k++;
00389 }
00390
00391 static inline int ape_decode_value(APEContext *ctx, APERice *rice)
00392 {
00393 int x, overflow;
00394
00395 if (ctx->fileversion < 3990) {
00396 int tmpk;
00397
00398 overflow = range_get_symbol(ctx, counts_3970, counts_diff_3970);
00399
00400 if (overflow == (MODEL_ELEMENTS - 1)) {
00401 tmpk = range_decode_bits(ctx, 5);
00402 overflow = 0;
00403 } else
00404 tmpk = (rice->k < 1) ? 0 : rice->k - 1;
00405
00406 if (tmpk <= 16)
00407 x = range_decode_bits(ctx, tmpk);
00408 else if (tmpk <= 32) {
00409 x = range_decode_bits(ctx, 16);
00410 x |= (range_decode_bits(ctx, tmpk - 16) << 16);
00411 } else {
00412 av_log(ctx->avctx, AV_LOG_ERROR, "Too many bits: %d\n", tmpk);
00413 return AVERROR_INVALIDDATA;
00414 }
00415 x += overflow << tmpk;
00416 } else {
00417 int base, pivot;
00418
00419 pivot = rice->ksum >> 5;
00420 if (pivot == 0)
00421 pivot = 1;
00422
00423 overflow = range_get_symbol(ctx, counts_3980, counts_diff_3980);
00424
00425 if (overflow == (MODEL_ELEMENTS - 1)) {
00426 overflow = range_decode_bits(ctx, 16) << 16;
00427 overflow |= range_decode_bits(ctx, 16);
00428 }
00429
00430 if (pivot < 0x10000) {
00431 base = range_decode_culfreq(ctx, pivot);
00432 range_decode_update(ctx, 1, base);
00433 } else {
00434 int base_hi = pivot, base_lo;
00435 int bbits = 0;
00436
00437 while (base_hi & ~0xFFFF) {
00438 base_hi >>= 1;
00439 bbits++;
00440 }
00441 base_hi = range_decode_culfreq(ctx, base_hi + 1);
00442 range_decode_update(ctx, 1, base_hi);
00443 base_lo = range_decode_culfreq(ctx, 1 << bbits);
00444 range_decode_update(ctx, 1, base_lo);
00445
00446 base = (base_hi << bbits) + base_lo;
00447 }
00448
00449 x = base + overflow * pivot;
00450 }
00451
00452 update_rice(rice, x);
00453
00454
00455 if (x & 1)
00456 return (x >> 1) + 1;
00457 else
00458 return -(x >> 1);
00459 }
00460
00461 static void entropy_decode(APEContext *ctx, int blockstodecode, int stereo)
00462 {
00463 int32_t *decoded0 = ctx->decoded0;
00464 int32_t *decoded1 = ctx->decoded1;
00465
00466 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00467
00468 memset(decoded0, 0, blockstodecode * sizeof(int32_t));
00469 memset(decoded1, 0, blockstodecode * sizeof(int32_t));
00470 } else {
00471 while (blockstodecode--) {
00472 *decoded0++ = ape_decode_value(ctx, &ctx->riceY);
00473 if (stereo)
00474 *decoded1++ = ape_decode_value(ctx, &ctx->riceX);
00475 }
00476 }
00477 }
00478
00479 static int init_entropy_decoder(APEContext *ctx)
00480 {
00481
00482 if (ctx->data_end - ctx->ptr < 6)
00483 return AVERROR_INVALIDDATA;
00484 ctx->CRC = bytestream_get_be32(&ctx->ptr);
00485
00486
00487 ctx->frameflags = 0;
00488 if ((ctx->fileversion > 3820) && (ctx->CRC & 0x80000000)) {
00489 ctx->CRC &= ~0x80000000;
00490
00491 if (ctx->data_end - ctx->ptr < 6)
00492 return AVERROR_INVALIDDATA;
00493 ctx->frameflags = bytestream_get_be32(&ctx->ptr);
00494 }
00495
00496
00497 ctx->riceX.k = 10;
00498 ctx->riceX.ksum = (1 << ctx->riceX.k) * 16;
00499 ctx->riceY.k = 10;
00500 ctx->riceY.ksum = (1 << ctx->riceY.k) * 16;
00501
00502
00503 ctx->ptr++;
00504
00505 range_start_decoding(ctx);
00506
00507 return 0;
00508 }
00509
00510 static const int32_t initial_coeffs[4] = {
00511 360, 317, -109, 98
00512 };
00513
00514 static void init_predictor_decoder(APEContext *ctx)
00515 {
00516 APEPredictor *p = &ctx->predictor;
00517
00518
00519 memset(p->historybuffer, 0, PREDICTOR_SIZE * sizeof(int32_t));
00520 p->buf = p->historybuffer;
00521
00522
00523 memcpy(p->coeffsA[0], initial_coeffs, sizeof(initial_coeffs));
00524 memcpy(p->coeffsA[1], initial_coeffs, sizeof(initial_coeffs));
00525 memset(p->coeffsB, 0, sizeof(p->coeffsB));
00526
00527 p->filterA[0] = p->filterA[1] = 0;
00528 p->filterB[0] = p->filterB[1] = 0;
00529 p->lastA[0] = p->lastA[1] = 0;
00530 }
00531
00533 static inline int APESIGN(int32_t x) {
00534 return (x < 0) - (x > 0);
00535 }
00536
00537 static av_always_inline int predictor_update_filter(APEPredictor *p,
00538 const int decoded, const int filter,
00539 const int delayA, const int delayB,
00540 const int adaptA, const int adaptB)
00541 {
00542 int32_t predictionA, predictionB, sign;
00543
00544 p->buf[delayA] = p->lastA[filter];
00545 p->buf[adaptA] = APESIGN(p->buf[delayA]);
00546 p->buf[delayA - 1] = p->buf[delayA] - p->buf[delayA - 1];
00547 p->buf[adaptA - 1] = APESIGN(p->buf[delayA - 1]);
00548
00549 predictionA = p->buf[delayA ] * p->coeffsA[filter][0] +
00550 p->buf[delayA - 1] * p->coeffsA[filter][1] +
00551 p->buf[delayA - 2] * p->coeffsA[filter][2] +
00552 p->buf[delayA - 3] * p->coeffsA[filter][3];
00553
00554
00555 p->buf[delayB] = p->filterA[filter ^ 1] - ((p->filterB[filter] * 31) >> 5);
00556 p->buf[adaptB] = APESIGN(p->buf[delayB]);
00557 p->buf[delayB - 1] = p->buf[delayB] - p->buf[delayB - 1];
00558 p->buf[adaptB - 1] = APESIGN(p->buf[delayB - 1]);
00559 p->filterB[filter] = p->filterA[filter ^ 1];
00560
00561 predictionB = p->buf[delayB ] * p->coeffsB[filter][0] +
00562 p->buf[delayB - 1] * p->coeffsB[filter][1] +
00563 p->buf[delayB - 2] * p->coeffsB[filter][2] +
00564 p->buf[delayB - 3] * p->coeffsB[filter][3] +
00565 p->buf[delayB - 4] * p->coeffsB[filter][4];
00566
00567 p->lastA[filter] = decoded + ((predictionA + (predictionB >> 1)) >> 10);
00568 p->filterA[filter] = p->lastA[filter] + ((p->filterA[filter] * 31) >> 5);
00569
00570 sign = APESIGN(decoded);
00571 p->coeffsA[filter][0] += p->buf[adaptA ] * sign;
00572 p->coeffsA[filter][1] += p->buf[adaptA - 1] * sign;
00573 p->coeffsA[filter][2] += p->buf[adaptA - 2] * sign;
00574 p->coeffsA[filter][3] += p->buf[adaptA - 3] * sign;
00575 p->coeffsB[filter][0] += p->buf[adaptB ] * sign;
00576 p->coeffsB[filter][1] += p->buf[adaptB - 1] * sign;
00577 p->coeffsB[filter][2] += p->buf[adaptB - 2] * sign;
00578 p->coeffsB[filter][3] += p->buf[adaptB - 3] * sign;
00579 p->coeffsB[filter][4] += p->buf[adaptB - 4] * sign;
00580
00581 return p->filterA[filter];
00582 }
00583
00584 static void predictor_decode_stereo(APEContext *ctx, int count)
00585 {
00586 APEPredictor *p = &ctx->predictor;
00587 int32_t *decoded0 = ctx->decoded0;
00588 int32_t *decoded1 = ctx->decoded1;
00589
00590 while (count--) {
00591
00592 *decoded0 = predictor_update_filter(p, *decoded0, 0, YDELAYA, YDELAYB,
00593 YADAPTCOEFFSA, YADAPTCOEFFSB);
00594 decoded0++;
00595 *decoded1 = predictor_update_filter(p, *decoded1, 1, XDELAYA, XDELAYB,
00596 XADAPTCOEFFSA, XADAPTCOEFFSB);
00597 decoded1++;
00598
00599
00600 p->buf++;
00601
00602
00603 if (p->buf == p->historybuffer + HISTORY_SIZE) {
00604 memmove(p->historybuffer, p->buf, PREDICTOR_SIZE * sizeof(int32_t));
00605 p->buf = p->historybuffer;
00606 }
00607 }
00608 }
00609
00610 static void predictor_decode_mono(APEContext *ctx, int count)
00611 {
00612 APEPredictor *p = &ctx->predictor;
00613 int32_t *decoded0 = ctx->decoded0;
00614 int32_t predictionA, currentA, A, sign;
00615
00616 currentA = p->lastA[0];
00617
00618 while (count--) {
00619 A = *decoded0;
00620
00621 p->buf[YDELAYA] = currentA;
00622 p->buf[YDELAYA - 1] = p->buf[YDELAYA] - p->buf[YDELAYA - 1];
00623
00624 predictionA = p->buf[YDELAYA ] * p->coeffsA[0][0] +
00625 p->buf[YDELAYA - 1] * p->coeffsA[0][1] +
00626 p->buf[YDELAYA - 2] * p->coeffsA[0][2] +
00627 p->buf[YDELAYA - 3] * p->coeffsA[0][3];
00628
00629 currentA = A + (predictionA >> 10);
00630
00631 p->buf[YADAPTCOEFFSA] = APESIGN(p->buf[YDELAYA ]);
00632 p->buf[YADAPTCOEFFSA - 1] = APESIGN(p->buf[YDELAYA - 1]);
00633
00634 sign = APESIGN(A);
00635 p->coeffsA[0][0] += p->buf[YADAPTCOEFFSA ] * sign;
00636 p->coeffsA[0][1] += p->buf[YADAPTCOEFFSA - 1] * sign;
00637 p->coeffsA[0][2] += p->buf[YADAPTCOEFFSA - 2] * sign;
00638 p->coeffsA[0][3] += p->buf[YADAPTCOEFFSA - 3] * sign;
00639
00640 p->buf++;
00641
00642
00643 if (p->buf == p->historybuffer + HISTORY_SIZE) {
00644 memmove(p->historybuffer, p->buf, PREDICTOR_SIZE * sizeof(int32_t));
00645 p->buf = p->historybuffer;
00646 }
00647
00648 p->filterA[0] = currentA + ((p->filterA[0] * 31) >> 5);
00649 *(decoded0++) = p->filterA[0];
00650 }
00651
00652 p->lastA[0] = currentA;
00653 }
00654
00655 static void do_init_filter(APEFilter *f, int16_t *buf, int order)
00656 {
00657 f->coeffs = buf;
00658 f->historybuffer = buf + order;
00659 f->delay = f->historybuffer + order * 2;
00660 f->adaptcoeffs = f->historybuffer + order;
00661
00662 memset(f->historybuffer, 0, (order * 2) * sizeof(int16_t));
00663 memset(f->coeffs, 0, order * sizeof(int16_t));
00664 f->avg = 0;
00665 }
00666
00667 static void init_filter(APEContext *ctx, APEFilter *f, int16_t *buf, int order)
00668 {
00669 do_init_filter(&f[0], buf, order);
00670 do_init_filter(&f[1], buf + order * 3 + HISTORY_SIZE, order);
00671 }
00672
00673 static void do_apply_filter(APEContext *ctx, int version, APEFilter *f,
00674 int32_t *data, int count, int order, int fracbits)
00675 {
00676 int res;
00677 int absres;
00678
00679 while (count--) {
00680
00681 res = ctx->dsp.scalarproduct_and_madd_int16(f->coeffs, f->delay - order,
00682 f->adaptcoeffs - order,
00683 order, APESIGN(*data));
00684 res = (res + (1 << (fracbits - 1))) >> fracbits;
00685 res += *data;
00686 *data++ = res;
00687
00688
00689 *f->delay++ = av_clip_int16(res);
00690
00691 if (version < 3980) {
00692
00693 f->adaptcoeffs[0] = (res == 0) ? 0 : ((res >> 28) & 8) - 4;
00694 f->adaptcoeffs[-4] >>= 1;
00695 f->adaptcoeffs[-8] >>= 1;
00696 } else {
00697
00698
00699
00700 absres = FFABS(res);
00701 if (absres)
00702 *f->adaptcoeffs = ((res & (-1<<31)) ^ (-1<<30)) >>
00703 (25 + (absres <= f->avg*3) + (absres <= f->avg*4/3));
00704 else
00705 *f->adaptcoeffs = 0;
00706
00707 f->avg += (absres - f->avg) / 16;
00708
00709 f->adaptcoeffs[-1] >>= 1;
00710 f->adaptcoeffs[-2] >>= 1;
00711 f->adaptcoeffs[-8] >>= 1;
00712 }
00713
00714 f->adaptcoeffs++;
00715
00716
00717 if (f->delay == f->historybuffer + HISTORY_SIZE + (order * 2)) {
00718 memmove(f->historybuffer, f->delay - (order * 2),
00719 (order * 2) * sizeof(int16_t));
00720 f->delay = f->historybuffer + order * 2;
00721 f->adaptcoeffs = f->historybuffer + order;
00722 }
00723 }
00724 }
00725
00726 static void apply_filter(APEContext *ctx, APEFilter *f,
00727 int32_t *data0, int32_t *data1,
00728 int count, int order, int fracbits)
00729 {
00730 do_apply_filter(ctx, ctx->fileversion, &f[0], data0, count, order, fracbits);
00731 if (data1)
00732 do_apply_filter(ctx, ctx->fileversion, &f[1], data1, count, order, fracbits);
00733 }
00734
00735 static void ape_apply_filters(APEContext *ctx, int32_t *decoded0,
00736 int32_t *decoded1, int count)
00737 {
00738 int i;
00739
00740 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00741 if (!ape_filter_orders[ctx->fset][i])
00742 break;
00743 apply_filter(ctx, ctx->filters[i], decoded0, decoded1, count,
00744 ape_filter_orders[ctx->fset][i],
00745 ape_filter_fracbits[ctx->fset][i]);
00746 }
00747 }
00748
00749 static int init_frame_decoder(APEContext *ctx)
00750 {
00751 int i, ret;
00752 if ((ret = init_entropy_decoder(ctx)) < 0)
00753 return ret;
00754 init_predictor_decoder(ctx);
00755
00756 for (i = 0; i < APE_FILTER_LEVELS; i++) {
00757 if (!ape_filter_orders[ctx->fset][i])
00758 break;
00759 init_filter(ctx, ctx->filters[i], ctx->filterbuf[i],
00760 ape_filter_orders[ctx->fset][i]);
00761 }
00762 return 0;
00763 }
00764
00765 static void ape_unpack_mono(APEContext *ctx, int count)
00766 {
00767 int32_t *decoded0 = ctx->decoded0;
00768 int32_t *decoded1 = ctx->decoded1;
00769
00770 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00771 entropy_decode(ctx, count, 0);
00772
00773 av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence mono\n");
00774 return;
00775 }
00776
00777 entropy_decode(ctx, count, 0);
00778 ape_apply_filters(ctx, decoded0, NULL, count);
00779
00780
00781 predictor_decode_mono(ctx, count);
00782
00783
00784 if (ctx->channels == 2) {
00785 memcpy(decoded1, decoded0, count * sizeof(*decoded1));
00786 }
00787 }
00788
00789 static void ape_unpack_stereo(APEContext *ctx, int count)
00790 {
00791 int32_t left, right;
00792 int32_t *decoded0 = ctx->decoded0;
00793 int32_t *decoded1 = ctx->decoded1;
00794
00795 if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) {
00796
00797 av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence stereo\n");
00798 return;
00799 }
00800
00801 entropy_decode(ctx, count, 1);
00802 ape_apply_filters(ctx, decoded0, decoded1, count);
00803
00804
00805 predictor_decode_stereo(ctx, count);
00806
00807
00808 while (count--) {
00809 left = *decoded1 - (*decoded0 / 2);
00810 right = left + *decoded0;
00811
00812 *(decoded0++) = left;
00813 *(decoded1++) = right;
00814 }
00815 }
00816
00817 static int ape_decode_frame(AVCodecContext *avctx, void *data,
00818 int *got_frame_ptr, AVPacket *avpkt)
00819 {
00820 const uint8_t *buf = avpkt->data;
00821 int buf_size = avpkt->size;
00822 APEContext *s = avctx->priv_data;
00823 int16_t *samples;
00824 int i, ret;
00825 int blockstodecode;
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 }
00881
00882 if (!s->data) {
00883 *got_frame_ptr = 0;
00884 return buf_size;
00885 }
00886
00887 blockstodecode = FFMIN(BLOCKS_PER_LOOP, s->samples);
00888
00889
00890 s->frame.nb_samples = blockstodecode;
00891 if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
00892 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00893 return ret;
00894 }
00895 samples = (int16_t *)s->frame.data[0];
00896
00897 s->error=0;
00898
00899 if ((s->channels == 1) || (s->frameflags & APE_FRAMECODE_PSEUDO_STEREO))
00900 ape_unpack_mono(s, blockstodecode);
00901 else
00902 ape_unpack_stereo(s, blockstodecode);
00903 emms_c();
00904
00905 if (s->error) {
00906 s->samples=0;
00907 av_log(avctx, AV_LOG_ERROR, "Error decoding frame\n");
00908 return AVERROR_INVALIDDATA;
00909 }
00910
00911 for (i = 0; i < blockstodecode; i++) {
00912 *samples++ = s->decoded0[i];
00913 if(s->channels == 2)
00914 *samples++ = s->decoded1[i];
00915 }
00916
00917 s->samples -= blockstodecode;
00918
00919 *got_frame_ptr = 1;
00920 *(AVFrame *)data = s->frame;
00921
00922 return (s->samples == 0) ? buf_size : 0;
00923 }
00924
00925 static void ape_flush(AVCodecContext *avctx)
00926 {
00927 APEContext *s = avctx->priv_data;
00928 s->samples= 0;
00929 }
00930
00931 AVCodec ff_ape_decoder = {
00932 .name = "ape",
00933 .type = AVMEDIA_TYPE_AUDIO,
00934 .id = CODEC_ID_APE,
00935 .priv_data_size = sizeof(APEContext),
00936 .init = ape_decode_init,
00937 .close = ape_decode_close,
00938 .decode = ape_decode_frame,
00939 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DELAY | CODEC_CAP_DR1,
00940 .flush = ape_flush,
00941 .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
00942 };