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Diffstat (limited to 'ffmpeg/libavcodec/apedec.c')
| -rw-r--r-- | ffmpeg/libavcodec/apedec.c | 1145 |
1 files changed, 1145 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/apedec.c b/ffmpeg/libavcodec/apedec.c new file mode 100644 index 0000000..1581d8e --- /dev/null +++ b/ffmpeg/libavcodec/apedec.c @@ -0,0 +1,1145 @@ +/* + * Monkey's Audio lossless audio decoder + * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org> + * based upon libdemac from Dave Chapman. + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "libavutil/avassert.h" +#include "libavutil/channel_layout.h" +#include "libavutil/opt.h" +#include "avcodec.h" +#include "dsputil.h" +#include "bytestream.h" +#include "internal.h" + +/** + * @file + * Monkey's Audio lossless audio decoder + */ + +#define MAX_CHANNELS 2 +#define MAX_BYTESPERSAMPLE 3 + +#define APE_FRAMECODE_MONO_SILENCE 1 +#define APE_FRAMECODE_STEREO_SILENCE 3 +#define APE_FRAMECODE_PSEUDO_STEREO 4 + +#define HISTORY_SIZE 512 +#define PREDICTOR_ORDER 8 +/** Total size of all predictor histories */ +#define PREDICTOR_SIZE 50 + +#define YDELAYA (18 + PREDICTOR_ORDER*4) +#define YDELAYB (18 + PREDICTOR_ORDER*3) +#define XDELAYA (18 + PREDICTOR_ORDER*2) +#define XDELAYB (18 + PREDICTOR_ORDER) + +#define YADAPTCOEFFSA 18 +#define XADAPTCOEFFSA 14 +#define YADAPTCOEFFSB 10 +#define XADAPTCOEFFSB 5 + +/** + * Possible compression levels + * @{ + */ +enum APECompressionLevel { + COMPRESSION_LEVEL_FAST = 1000, + COMPRESSION_LEVEL_NORMAL = 2000, + COMPRESSION_LEVEL_HIGH = 3000, + COMPRESSION_LEVEL_EXTRA_HIGH = 4000, + COMPRESSION_LEVEL_INSANE = 5000 +}; +/** @} */ + +#define APE_FILTER_LEVELS 3 + +/** Filter orders depending on compression level */ +static const uint16_t ape_filter_orders[5][APE_FILTER_LEVELS] = { + { 0, 0, 0 }, + { 16, 0, 0 }, + { 64, 0, 0 }, + { 32, 256, 0 }, + { 16, 256, 1280 } +}; + +/** Filter fraction bits depending on compression level */ +static const uint8_t ape_filter_fracbits[5][APE_FILTER_LEVELS] = { + { 0, 0, 0 }, + { 11, 0, 0 }, + { 11, 0, 0 }, + { 10, 13, 0 }, + { 11, 13, 15 } +}; + + +/** Filters applied to the decoded data */ +typedef struct APEFilter { + int16_t *coeffs; ///< actual coefficients used in filtering + int16_t *adaptcoeffs; ///< adaptive filter coefficients used for correcting of actual filter coefficients + int16_t *historybuffer; ///< filter memory + int16_t *delay; ///< filtered values + + int avg; +} APEFilter; + +typedef struct APERice { + uint32_t k; + uint32_t ksum; +} APERice; + +typedef struct APERangecoder { + uint32_t low; ///< low end of interval + uint32_t range; ///< length of interval + uint32_t help; ///< bytes_to_follow resp. intermediate value + unsigned int buffer; ///< buffer for input/output +} APERangecoder; + +/** Filter histories */ +typedef struct APEPredictor { + int32_t *buf; + + int32_t lastA[2]; + + int32_t filterA[2]; + int32_t filterB[2]; + + int32_t coeffsA[2][4]; ///< adaption coefficients + int32_t coeffsB[2][5]; ///< adaption coefficients + int32_t historybuffer[HISTORY_SIZE + PREDICTOR_SIZE]; +} APEPredictor; + +/** Decoder context */ +typedef struct APEContext { + AVClass *class; ///< class for AVOptions + AVCodecContext *avctx; + DSPContext dsp; + int channels; + int samples; ///< samples left to decode in current frame + int bps; + + int fileversion; ///< codec version, very important in decoding process + int compression_level; ///< compression levels + int fset; ///< which filter set to use (calculated from compression level) + int flags; ///< global decoder flags + + uint32_t CRC; ///< frame CRC + int frameflags; ///< frame flags + APEPredictor predictor; ///< predictor used for final reconstruction + + int32_t *decoded_buffer; + int decoded_size; + int32_t *decoded[MAX_CHANNELS]; ///< decoded data for each channel + int blocks_per_loop; ///< maximum number of samples to decode for each call + + int16_t* filterbuf[APE_FILTER_LEVELS]; ///< filter memory + + APERangecoder rc; ///< rangecoder used to decode actual values + APERice riceX; ///< rice code parameters for the second channel + APERice riceY; ///< rice code parameters for the first channel + APEFilter filters[APE_FILTER_LEVELS][2]; ///< filters used for reconstruction + + uint8_t *data; ///< current frame data + uint8_t *data_end; ///< frame data end + int data_size; ///< frame data allocated size + const uint8_t *ptr; ///< current position in frame data + + int error; + + void (*entropy_decode_mono)(struct APEContext *ctx, int blockstodecode); + void (*entropy_decode_stereo)(struct APEContext *ctx, int blockstodecode); + void (*predictor_decode_mono)(struct APEContext *ctx, int count); + void (*predictor_decode_stereo)(struct APEContext *ctx, int count); +} APEContext; + +static void ape_apply_filters(APEContext *ctx, int32_t *decoded0, + int32_t *decoded1, int count); + +static void entropy_decode_mono_3900(APEContext *ctx, int blockstodecode); +static void entropy_decode_stereo_3900(APEContext *ctx, int blockstodecode); +static void entropy_decode_mono_3990(APEContext *ctx, int blockstodecode); +static void entropy_decode_stereo_3990(APEContext *ctx, int blockstodecode); + +static void predictor_decode_mono_3930(APEContext *ctx, int count); +static void predictor_decode_stereo_3930(APEContext *ctx, int count); +static void predictor_decode_mono_3950(APEContext *ctx, int count); +static void predictor_decode_stereo_3950(APEContext *ctx, int count); + +// TODO: dsputilize + +static av_cold int ape_decode_close(AVCodecContext *avctx) +{ + APEContext *s = avctx->priv_data; + int i; + + for (i = 0; i < APE_FILTER_LEVELS; i++) + av_freep(&s->filterbuf[i]); + + av_freep(&s->decoded_buffer); + av_freep(&s->data); + s->decoded_size = s->data_size = 0; + + return 0; +} + +static av_cold int ape_decode_init(AVCodecContext *avctx) +{ + APEContext *s = avctx->priv_data; + int i; + + if (avctx->extradata_size != 6) { + av_log(avctx, AV_LOG_ERROR, "Incorrect extradata\n"); + return AVERROR(EINVAL); + } + if (avctx->channels > 2) { + av_log(avctx, AV_LOG_ERROR, "Only mono and stereo is supported\n"); + return AVERROR(EINVAL); + } + s->bps = avctx->bits_per_coded_sample; + switch (s->bps) { + case 8: + avctx->sample_fmt = AV_SAMPLE_FMT_U8P; + break; + case 16: + avctx->sample_fmt = AV_SAMPLE_FMT_S16P; + break; + case 24: + avctx->sample_fmt = AV_SAMPLE_FMT_S32P; + break; + default: + avpriv_request_sample(avctx, + "%d bits per coded sample", s->bps); + return AVERROR_PATCHWELCOME; + } + s->avctx = avctx; + s->channels = avctx->channels; + s->fileversion = AV_RL16(avctx->extradata); + s->compression_level = AV_RL16(avctx->extradata + 2); + s->flags = AV_RL16(avctx->extradata + 4); + + av_log(avctx, AV_LOG_DEBUG, "Compression Level: %d - Flags: %d\n", + s->compression_level, s->flags); + if (s->compression_level % 1000 || s->compression_level > COMPRESSION_LEVEL_INSANE || !s->compression_level) { + av_log(avctx, AV_LOG_ERROR, "Incorrect compression level %d\n", + s->compression_level); + return AVERROR_INVALIDDATA; + } + s->fset = s->compression_level / 1000 - 1; + for (i = 0; i < APE_FILTER_LEVELS; i++) { + if (!ape_filter_orders[s->fset][i]) + break; + FF_ALLOC_OR_GOTO(avctx, s->filterbuf[i], + (ape_filter_orders[s->fset][i] * 3 + HISTORY_SIZE) * 4, + filter_alloc_fail); + } + + if (s->fileversion < 3990) { + s->entropy_decode_mono = entropy_decode_mono_3900; + s->entropy_decode_stereo = entropy_decode_stereo_3900; + } else { + s->entropy_decode_mono = entropy_decode_mono_3990; + s->entropy_decode_stereo = entropy_decode_stereo_3990; + } + + if (s->fileversion < 3950) { + s->predictor_decode_mono = predictor_decode_mono_3930; + s->predictor_decode_stereo = predictor_decode_stereo_3930; + } else { + s->predictor_decode_mono = predictor_decode_mono_3950; + s->predictor_decode_stereo = predictor_decode_stereo_3950; + } + + ff_dsputil_init(&s->dsp, avctx); + avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO; + + return 0; +filter_alloc_fail: + ape_decode_close(avctx); + return AVERROR(ENOMEM); +} + +/** + * @name APE range decoding functions + * @{ + */ + +#define CODE_BITS 32 +#define TOP_VALUE ((unsigned int)1 << (CODE_BITS-1)) +#define SHIFT_BITS (CODE_BITS - 9) +#define EXTRA_BITS ((CODE_BITS-2) % 8 + 1) +#define BOTTOM_VALUE (TOP_VALUE >> 8) + +/** Start the decoder */ +static inline void range_start_decoding(APEContext *ctx) +{ + ctx->rc.buffer = bytestream_get_byte(&ctx->ptr); + ctx->rc.low = ctx->rc.buffer >> (8 - EXTRA_BITS); + ctx->rc.range = (uint32_t) 1 << EXTRA_BITS; +} + +/** Perform normalization */ +static inline void range_dec_normalize(APEContext *ctx) +{ + while (ctx->rc.range <= BOTTOM_VALUE) { + ctx->rc.buffer <<= 8; + if(ctx->ptr < ctx->data_end) { + ctx->rc.buffer += *ctx->ptr; + ctx->ptr++; + } else { + ctx->error = 1; + } + ctx->rc.low = (ctx->rc.low << 8) | ((ctx->rc.buffer >> 1) & 0xFF); + ctx->rc.range <<= 8; + } +} + +/** + * Calculate culmulative frequency for next symbol. Does NO update! + * @param ctx decoder context + * @param tot_f is the total frequency or (code_value)1<<shift + * @return the culmulative frequency + */ +static inline int range_decode_culfreq(APEContext *ctx, int tot_f) +{ + range_dec_normalize(ctx); + ctx->rc.help = ctx->rc.range / tot_f; + return ctx->rc.low / ctx->rc.help; +} + +/** + * Decode value with given size in bits + * @param ctx decoder context + * @param shift number of bits to decode + */ +static inline int range_decode_culshift(APEContext *ctx, int shift) +{ + range_dec_normalize(ctx); + ctx->rc.help = ctx->rc.range >> shift; + return ctx->rc.low / ctx->rc.help; +} + + +/** + * Update decoding state + * @param ctx decoder context + * @param sy_f the interval length (frequency of the symbol) + * @param lt_f the lower end (frequency sum of < symbols) + */ +static inline void range_decode_update(APEContext *ctx, int sy_f, int lt_f) +{ + ctx->rc.low -= ctx->rc.help * lt_f; + ctx->rc.range = ctx->rc.help * sy_f; +} + +/** Decode n bits (n <= 16) without modelling */ +static inline int range_decode_bits(APEContext *ctx, int n) +{ + int sym = range_decode_culshift(ctx, n); + range_decode_update(ctx, 1, sym); + return sym; +} + + +#define MODEL_ELEMENTS 64 + +/** + * Fixed probabilities for symbols in Monkey Audio version 3.97 + */ +static const uint16_t counts_3970[22] = { + 0, 14824, 28224, 39348, 47855, 53994, 58171, 60926, + 62682, 63786, 64463, 64878, 65126, 65276, 65365, 65419, + 65450, 65469, 65480, 65487, 65491, 65493, +}; + +/** + * Probability ranges for symbols in Monkey Audio version 3.97 + */ +static const uint16_t counts_diff_3970[21] = { + 14824, 13400, 11124, 8507, 6139, 4177, 2755, 1756, + 1104, 677, 415, 248, 150, 89, 54, 31, + 19, 11, 7, 4, 2, +}; + +/** + * Fixed probabilities for symbols in Monkey Audio version 3.98 + */ +static const uint16_t counts_3980[22] = { + 0, 19578, 36160, 48417, 56323, 60899, 63265, 64435, + 64971, 65232, 65351, 65416, 65447, 65466, 65476, 65482, + 65485, 65488, 65490, 65491, 65492, 65493, +}; + +/** + * Probability ranges for symbols in Monkey Audio version 3.98 + */ +static const uint16_t counts_diff_3980[21] = { + 19578, 16582, 12257, 7906, 4576, 2366, 1170, 536, + 261, 119, 65, 31, 19, 10, 6, 3, + 3, 2, 1, 1, 1, +}; + +/** + * Decode symbol + * @param ctx decoder context + * @param counts probability range start position + * @param counts_diff probability range widths + */ +static inline int range_get_symbol(APEContext *ctx, + const uint16_t counts[], + const uint16_t counts_diff[]) +{ + int symbol, cf; + + cf = range_decode_culshift(ctx, 16); + + if(cf > 65492){ + symbol= cf - 65535 + 63; + range_decode_update(ctx, 1, cf); + if(cf > 65535) + ctx->error=1; + return symbol; + } + /* figure out the symbol inefficiently; a binary search would be much better */ + for (symbol = 0; counts[symbol + 1] <= cf; symbol++); + + range_decode_update(ctx, counts_diff[symbol], counts[symbol]); + + return symbol; +} +/** @} */ // group rangecoder + +static inline void update_rice(APERice *rice, unsigned int x) +{ + int lim = rice->k ? (1 << (rice->k + 4)) : 0; + rice->ksum += ((x + 1) / 2) - ((rice->ksum + 16) >> 5); + + if (rice->ksum < lim) + rice->k--; + else if (rice->ksum >= (1 << (rice->k + 5))) + rice->k++; +} + +static inline int ape_decode_value_3900(APEContext *ctx, APERice *rice) +{ + unsigned int x, overflow; + int tmpk; + + overflow = range_get_symbol(ctx, counts_3970, counts_diff_3970); + + if (overflow == (MODEL_ELEMENTS - 1)) { + tmpk = range_decode_bits(ctx, 5); + overflow = 0; + } else + tmpk = (rice->k < 1) ? 0 : rice->k - 1; + + if (tmpk <= 16) + x = range_decode_bits(ctx, tmpk); + else if (tmpk <= 32) { + x = range_decode_bits(ctx, 16); + x |= (range_decode_bits(ctx, tmpk - 16) << 16); + } else { + av_log(ctx->avctx, AV_LOG_ERROR, "Too many bits: %d\n", tmpk); + return AVERROR_INVALIDDATA; + } + x += overflow << tmpk; + + update_rice(rice, x); + + /* Convert to signed */ + if (x & 1) + return (x >> 1) + 1; + else + return -(x >> 1); +} + +static inline int ape_decode_value_3990(APEContext *ctx, APERice *rice) +{ + unsigned int x, overflow; + int base, pivot; + + pivot = rice->ksum >> 5; + if (pivot == 0) + pivot = 1; + + overflow = range_get_symbol(ctx, counts_3980, counts_diff_3980); + + if (overflow == (MODEL_ELEMENTS - 1)) { + overflow = range_decode_bits(ctx, 16) << 16; + overflow |= range_decode_bits(ctx, 16); + } + + if (pivot < 0x10000) { + base = range_decode_culfreq(ctx, pivot); + range_decode_update(ctx, 1, base); + } else { + int base_hi = pivot, base_lo; + int bbits = 0; + + while (base_hi & ~0xFFFF) { + base_hi >>= 1; + bbits++; + } + base_hi = range_decode_culfreq(ctx, base_hi + 1); + range_decode_update(ctx, 1, base_hi); + base_lo = range_decode_culfreq(ctx, 1 << bbits); + range_decode_update(ctx, 1, base_lo); + + base = (base_hi << bbits) + base_lo; + } + + x = base + overflow * pivot; + + update_rice(rice, x); + + /* Convert to signed */ + if (x & 1) + return (x >> 1) + 1; + else + return -(x >> 1); +} + +static void entropy_decode_mono_3900(APEContext *ctx, int blockstodecode) +{ + int32_t *decoded0 = ctx->decoded[0]; + + while (blockstodecode--) + *decoded0++ = ape_decode_value_3900(ctx, &ctx->riceY); +} + +static void entropy_decode_stereo_3900(APEContext *ctx, int blockstodecode) +{ + int32_t *decoded0 = ctx->decoded[0]; + int32_t *decoded1 = ctx->decoded[1]; + + while (blockstodecode--) { + *decoded0++ = ape_decode_value_3900(ctx, &ctx->riceY); + *decoded1++ = ape_decode_value_3900(ctx, &ctx->riceX); + } +} + +static void entropy_decode_mono_3990(APEContext *ctx, int blockstodecode) +{ + int32_t *decoded0 = ctx->decoded[0]; + + while (blockstodecode--) + *decoded0++ = ape_decode_value_3990(ctx, &ctx->riceY); +} + +static void entropy_decode_stereo_3990(APEContext *ctx, int blockstodecode) +{ + int32_t *decoded0 = ctx->decoded[0]; + int32_t *decoded1 = ctx->decoded[1]; + + while (blockstodecode--) { + *decoded0++ = ape_decode_value_3990(ctx, &ctx->riceY); + *decoded1++ = ape_decode_value_3990(ctx, &ctx->riceX); + } +} + +static int init_entropy_decoder(APEContext *ctx) +{ + /* Read the CRC */ + if (ctx->data_end - ctx->ptr < 6) + return AVERROR_INVALIDDATA; + ctx->CRC = bytestream_get_be32(&ctx->ptr); + + /* Read the frame flags if they exist */ + ctx->frameflags = 0; + if ((ctx->fileversion > 3820) && (ctx->CRC & 0x80000000)) { + ctx->CRC &= ~0x80000000; + + if (ctx->data_end - ctx->ptr < 6) + return AVERROR_INVALIDDATA; + ctx->frameflags = bytestream_get_be32(&ctx->ptr); + } + + /* Initialize the rice structs */ + ctx->riceX.k = 10; + ctx->riceX.ksum = (1 << ctx->riceX.k) * 16; + ctx->riceY.k = 10; + ctx->riceY.ksum = (1 << ctx->riceY.k) * 16; + + /* The first 8 bits of input are ignored. */ + ctx->ptr++; + + range_start_decoding(ctx); + + return 0; +} + +static const int32_t initial_coeffs[4] = { + 360, 317, -109, 98 +}; + +static void init_predictor_decoder(APEContext *ctx) +{ + APEPredictor *p = &ctx->predictor; + + /* Zero the history buffers */ + memset(p->historybuffer, 0, PREDICTOR_SIZE * sizeof(*p->historybuffer)); + p->buf = p->historybuffer; + + /* Initialize and zero the coefficients */ + memcpy(p->coeffsA[0], initial_coeffs, sizeof(initial_coeffs)); + memcpy(p->coeffsA[1], initial_coeffs, sizeof(initial_coeffs)); + memset(p->coeffsB, 0, sizeof(p->coeffsB)); + + p->filterA[0] = p->filterA[1] = 0; + p->filterB[0] = p->filterB[1] = 0; + p->lastA[0] = p->lastA[1] = 0; +} + +/** Get inverse sign of integer (-1 for positive, 1 for negative and 0 for zero) */ +static inline int APESIGN(int32_t x) { + return (x < 0) - (x > 0); +} + +static av_always_inline int predictor_update_3930(APEPredictor *p, + const int decoded, const int filter, + const int delayA) +{ + int32_t predictionA, sign; + int32_t d0, d1, d2, d3; + + p->buf[delayA] = p->lastA[filter]; + d0 = p->buf[delayA ]; + d1 = p->buf[delayA ] - p->buf[delayA - 1]; + d2 = p->buf[delayA - 1] - p->buf[delayA - 2]; + d3 = p->buf[delayA - 2] - p->buf[delayA - 3]; + + predictionA = d0 * p->coeffsA[filter][0] + + d1 * p->coeffsA[filter][1] + + d2 * p->coeffsA[filter][2] + + d3 * p->coeffsA[filter][3]; + + p->lastA[filter] = decoded + (predictionA >> 9); + p->filterA[filter] = p->lastA[filter] + ((p->filterA[filter] * 31) >> 5); + + sign = APESIGN(decoded); + p->coeffsA[filter][0] += ((d0 < 0) * 2 - 1) * sign; + p->coeffsA[filter][1] += ((d1 < 0) * 2 - 1) * sign; + p->coeffsA[filter][2] += ((d2 < 0) * 2 - 1) * sign; + p->coeffsA[filter][3] += ((d3 < 0) * 2 - 1) * sign; + + return p->filterA[filter]; +} + +static void predictor_decode_stereo_3930(APEContext *ctx, int count) +{ + APEPredictor *p = &ctx->predictor; + int32_t *decoded0 = ctx->decoded[0]; + int32_t *decoded1 = ctx->decoded[1]; + + ape_apply_filters(ctx, ctx->decoded[0], ctx->decoded[1], count); + + while (count--) { + /* Predictor Y */ + int Y = *decoded1, X = *decoded0; + *decoded0 = predictor_update_3930(p, Y, 0, YDELAYA); + decoded0++; + *decoded1 = predictor_update_3930(p, X, 1, XDELAYA); + decoded1++; + + /* Combined */ + p->buf++; + + /* Have we filled the history buffer? */ + if (p->buf == p->historybuffer + HISTORY_SIZE) { + memmove(p->historybuffer, p->buf, + PREDICTOR_SIZE * sizeof(*p->historybuffer)); + p->buf = p->historybuffer; + } + } +} + +static void predictor_decode_mono_3930(APEContext *ctx, int count) +{ + APEPredictor *p = &ctx->predictor; + int32_t *decoded0 = ctx->decoded[0]; + + ape_apply_filters(ctx, ctx->decoded[0], NULL, count); + + while (count--) { + *decoded0 = predictor_update_3930(p, *decoded0, 0, YDELAYA); + decoded0++; + + p->buf++; + + /* Have we filled the history buffer? */ + if (p->buf == p->historybuffer + HISTORY_SIZE) { + memmove(p->historybuffer, p->buf, + PREDICTOR_SIZE * sizeof(*p->historybuffer)); + p->buf = p->historybuffer; + } + } +} + +static av_always_inline int predictor_update_filter(APEPredictor *p, + const int decoded, const int filter, + const int delayA, const int delayB, + const int adaptA, const int adaptB) +{ + int32_t predictionA, predictionB, sign; + + p->buf[delayA] = p->lastA[filter]; + p->buf[adaptA] = APESIGN(p->buf[delayA]); + p->buf[delayA - 1] = p->buf[delayA] - p->buf[delayA - 1]; + p->buf[adaptA - 1] = APESIGN(p->buf[delayA - 1]); + + predictionA = p->buf[delayA ] * p->coeffsA[filter][0] + + p->buf[delayA - 1] * p->coeffsA[filter][1] + + p->buf[delayA - 2] * p->coeffsA[filter][2] + + p->buf[delayA - 3] * p->coeffsA[filter][3]; + + /* Apply a scaled first-order filter compression */ + p->buf[delayB] = p->filterA[filter ^ 1] - ((p->filterB[filter] * 31) >> 5); + p->buf[adaptB] = APESIGN(p->buf[delayB]); + p->buf[delayB - 1] = p->buf[delayB] - p->buf[delayB - 1]; + p->buf[adaptB - 1] = APESIGN(p->buf[delayB - 1]); + p->filterB[filter] = p->filterA[filter ^ 1]; + + predictionB = p->buf[delayB ] * p->coeffsB[filter][0] + + p->buf[delayB - 1] * p->coeffsB[filter][1] + + p->buf[delayB - 2] * p->coeffsB[filter][2] + + p->buf[delayB - 3] * p->coeffsB[filter][3] + + p->buf[delayB - 4] * p->coeffsB[filter][4]; + + p->lastA[filter] = decoded + ((predictionA + (predictionB >> 1)) >> 10); + p->filterA[filter] = p->lastA[filter] + ((p->filterA[filter] * 31) >> 5); + + sign = APESIGN(decoded); + p->coeffsA[filter][0] += p->buf[adaptA ] * sign; + p->coeffsA[filter][1] += p->buf[adaptA - 1] * sign; + p->coeffsA[filter][2] += p->buf[adaptA - 2] * sign; + p->coeffsA[filter][3] += p->buf[adaptA - 3] * sign; + p->coeffsB[filter][0] += p->buf[adaptB ] * sign; + p->coeffsB[filter][1] += p->buf[adaptB - 1] * sign; + p->coeffsB[filter][2] += p->buf[adaptB - 2] * sign; + p->coeffsB[filter][3] += p->buf[adaptB - 3] * sign; + p->coeffsB[filter][4] += p->buf[adaptB - 4] * sign; + + return p->filterA[filter]; +} + +static void predictor_decode_stereo_3950(APEContext *ctx, int count) +{ + APEPredictor *p = &ctx->predictor; + int32_t *decoded0 = ctx->decoded[0]; + int32_t *decoded1 = ctx->decoded[1]; + + ape_apply_filters(ctx, ctx->decoded[0], ctx->decoded[1], count); + + while (count--) { + /* Predictor Y */ + *decoded0 = predictor_update_filter(p, *decoded0, 0, YDELAYA, YDELAYB, + YADAPTCOEFFSA, YADAPTCOEFFSB); + decoded0++; + *decoded1 = predictor_update_filter(p, *decoded1, 1, XDELAYA, XDELAYB, + XADAPTCOEFFSA, XADAPTCOEFFSB); + decoded1++; + + /* Combined */ + p->buf++; + + /* Have we filled the history buffer? */ + if (p->buf == p->historybuffer + HISTORY_SIZE) { + memmove(p->historybuffer, p->buf, + PREDICTOR_SIZE * sizeof(*p->historybuffer)); + p->buf = p->historybuffer; + } + } +} + +static void predictor_decode_mono_3950(APEContext *ctx, int count) +{ + APEPredictor *p = &ctx->predictor; + int32_t *decoded0 = ctx->decoded[0]; + int32_t predictionA, currentA, A, sign; + + ape_apply_filters(ctx, ctx->decoded[0], NULL, count); + + currentA = p->lastA[0]; + + while (count--) { + A = *decoded0; + + p->buf[YDELAYA] = currentA; + p->buf[YDELAYA - 1] = p->buf[YDELAYA] - p->buf[YDELAYA - 1]; + + predictionA = p->buf[YDELAYA ] * p->coeffsA[0][0] + + p->buf[YDELAYA - 1] * p->coeffsA[0][1] + + p->buf[YDELAYA - 2] * p->coeffsA[0][2] + + p->buf[YDELAYA - 3] * p->coeffsA[0][3]; + + currentA = A + (predictionA >> 10); + + p->buf[YADAPTCOEFFSA] = APESIGN(p->buf[YDELAYA ]); + p->buf[YADAPTCOEFFSA - 1] = APESIGN(p->buf[YDELAYA - 1]); + + sign = APESIGN(A); + p->coeffsA[0][0] += p->buf[YADAPTCOEFFSA ] * sign; + p->coeffsA[0][1] += p->buf[YADAPTCOEFFSA - 1] * sign; + p->coeffsA[0][2] += p->buf[YADAPTCOEFFSA - 2] * sign; + p->coeffsA[0][3] += p->buf[YADAPTCOEFFSA - 3] * sign; + + p->buf++; + + /* Have we filled the history buffer? */ + if (p->buf == p->historybuffer + HISTORY_SIZE) { + memmove(p->historybuffer, p->buf, + PREDICTOR_SIZE * sizeof(*p->historybuffer)); + p->buf = p->historybuffer; + } + + p->filterA[0] = currentA + ((p->filterA[0] * 31) >> 5); + *(decoded0++) = p->filterA[0]; + } + + p->lastA[0] = currentA; +} + +static void do_init_filter(APEFilter *f, int16_t *buf, int order) +{ + f->coeffs = buf; + f->historybuffer = buf + order; + f->delay = f->historybuffer + order * 2; + f->adaptcoeffs = f->historybuffer + order; + + memset(f->historybuffer, 0, (order * 2) * sizeof(*f->historybuffer)); + memset(f->coeffs, 0, order * sizeof(*f->coeffs)); + f->avg = 0; +} + +static void init_filter(APEContext *ctx, APEFilter *f, int16_t *buf, int order) +{ + do_init_filter(&f[0], buf, order); + do_init_filter(&f[1], buf + order * 3 + HISTORY_SIZE, order); +} + +static void do_apply_filter(APEContext *ctx, int version, APEFilter *f, + int32_t *data, int count, int order, int fracbits) +{ + int res; + int absres; + + while (count--) { + /* round fixedpoint scalar product */ + res = ctx->dsp.scalarproduct_and_madd_int16(f->coeffs, f->delay - order, + f->adaptcoeffs - order, + order, APESIGN(*data)); + res = (res + (1 << (fracbits - 1))) >> fracbits; + res += *data; + *data++ = res; + + /* Update the output history */ + *f->delay++ = av_clip_int16(res); + + if (version < 3980) { + /* Version ??? to < 3.98 files (untested) */ + f->adaptcoeffs[0] = (res == 0) ? 0 : ((res >> 28) & 8) - 4; + f->adaptcoeffs[-4] >>= 1; + f->adaptcoeffs[-8] >>= 1; + } else { + /* Version 3.98 and later files */ + + /* Update the adaption coefficients */ + absres = FFABS(res); + if (absres) + *f->adaptcoeffs = ((res & (-1<<31)) ^ (-1<<30)) >> + (25 + (absres <= f->avg*3) + (absres <= f->avg*4/3)); + else + *f->adaptcoeffs = 0; + + f->avg += (absres - f->avg) / 16; + + f->adaptcoeffs[-1] >>= 1; + f->adaptcoeffs[-2] >>= 1; + f->adaptcoeffs[-8] >>= 1; + } + + f->adaptcoeffs++; + + /* Have we filled the history buffer? */ + if (f->delay == f->historybuffer + HISTORY_SIZE + (order * 2)) { + memmove(f->historybuffer, f->delay - (order * 2), + (order * 2) * sizeof(*f->historybuffer)); + f->delay = f->historybuffer + order * 2; + f->adaptcoeffs = f->historybuffer + order; + } + } +} + +static void apply_filter(APEContext *ctx, APEFilter *f, + int32_t *data0, int32_t *data1, + int count, int order, int fracbits) +{ + do_apply_filter(ctx, ctx->fileversion, &f[0], data0, count, order, fracbits); + if (data1) + do_apply_filter(ctx, ctx->fileversion, &f[1], data1, count, order, fracbits); +} + +static void ape_apply_filters(APEContext *ctx, int32_t *decoded0, + int32_t *decoded1, int count) +{ + int i; + + for (i = 0; i < APE_FILTER_LEVELS; i++) { + if (!ape_filter_orders[ctx->fset][i]) + break; + apply_filter(ctx, ctx->filters[i], decoded0, decoded1, count, + ape_filter_orders[ctx->fset][i], + ape_filter_fracbits[ctx->fset][i]); + } +} + +static int init_frame_decoder(APEContext *ctx) +{ + int i, ret; + if ((ret = init_entropy_decoder(ctx)) < 0) + return ret; + init_predictor_decoder(ctx); + + for (i = 0; i < APE_FILTER_LEVELS; i++) { + if (!ape_filter_orders[ctx->fset][i]) + break; + init_filter(ctx, ctx->filters[i], ctx->filterbuf[i], + ape_filter_orders[ctx->fset][i]); + } + return 0; +} + +static void ape_unpack_mono(APEContext *ctx, int count) +{ + if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) { + /* We are pure silence, so we're done. */ + av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence mono\n"); + return; + } + + ctx->entropy_decode_mono(ctx, count); + + /* Now apply the predictor decoding */ + ctx->predictor_decode_mono(ctx, count); + + /* Pseudo-stereo - just copy left channel to right channel */ + if (ctx->channels == 2) { + memcpy(ctx->decoded[1], ctx->decoded[0], count * sizeof(*ctx->decoded[1])); + } +} + +static void ape_unpack_stereo(APEContext *ctx, int count) +{ + int32_t left, right; + int32_t *decoded0 = ctx->decoded[0]; + int32_t *decoded1 = ctx->decoded[1]; + + if (ctx->frameflags & APE_FRAMECODE_STEREO_SILENCE) { + /* We are pure silence, so we're done. */ + av_log(ctx->avctx, AV_LOG_DEBUG, "pure silence stereo\n"); + return; + } + + ctx->entropy_decode_stereo(ctx, count); + + /* Now apply the predictor decoding */ + ctx->predictor_decode_stereo(ctx, count); + + /* Decorrelate and scale to output depth */ + while (count--) { + left = *decoded1 - (*decoded0 / 2); + right = left + *decoded0; + + *(decoded0++) = left; + *(decoded1++) = right; + } +} + +static int ape_decode_frame(AVCodecContext *avctx, void *data, + int *got_frame_ptr, AVPacket *avpkt) +{ + AVFrame *frame = data; + const uint8_t *buf = avpkt->data; + APEContext *s = avctx->priv_data; + uint8_t *sample8; + int16_t *sample16; + int32_t *sample24; + int i, ch, ret; + int blockstodecode; + + /* this should never be negative, but bad things will happen if it is, so + check it just to make sure. */ + av_assert0(s->samples >= 0); + + if(!s->samples){ + uint32_t nblocks, offset; + int buf_size; + + if (!avpkt->size) { + *got_frame_ptr = 0; + return 0; + } + if (avpkt->size < 8) { + av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); + return AVERROR_INVALIDDATA; + } + buf_size = avpkt->size & ~3; + if (buf_size != avpkt->size) { + av_log(avctx, AV_LOG_WARNING, "packet size is not a multiple of 4. " + "extra bytes at the end will be skipped.\n"); + } + if (s->fileversion < 3950) // previous versions overread two bytes + buf_size += 2; + av_fast_malloc(&s->data, &s->data_size, buf_size); + if (!s->data) + return AVERROR(ENOMEM); + s->dsp.bswap_buf((uint32_t*)s->data, (const uint32_t*)buf, buf_size >> 2); + memset(s->data + (buf_size & ~3), 0, buf_size & 3); + s->ptr = s->data; + s->data_end = s->data + buf_size; + + nblocks = bytestream_get_be32(&s->ptr); + offset = bytestream_get_be32(&s->ptr); + if (offset > 3) { + av_log(avctx, AV_LOG_ERROR, "Incorrect offset passed\n"); + s->data = NULL; + return AVERROR_INVALIDDATA; + } + if (s->data_end - s->ptr < offset) { + av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); + return AVERROR_INVALIDDATA; + } + s->ptr += offset; + + if (!nblocks || nblocks > INT_MAX) { + av_log(avctx, AV_LOG_ERROR, "Invalid sample count: %u.\n", nblocks); + return AVERROR_INVALIDDATA; + } + s->samples = nblocks; + + /* Initialize the frame decoder */ + if (init_frame_decoder(s) < 0) { + av_log(avctx, AV_LOG_ERROR, "Error reading frame header\n"); + return AVERROR_INVALIDDATA; + } + } + + if (!s->data) { + *got_frame_ptr = 0; + return avpkt->size; + } + + blockstodecode = FFMIN(s->blocks_per_loop, s->samples); + + /* reallocate decoded sample buffer if needed */ + av_fast_malloc(&s->decoded_buffer, &s->decoded_size, + 2 * FFALIGN(blockstodecode, 8) * sizeof(*s->decoded_buffer)); + if (!s->decoded_buffer) + return AVERROR(ENOMEM); + memset(s->decoded_buffer, 0, s->decoded_size); + s->decoded[0] = s->decoded_buffer; + s->decoded[1] = s->decoded_buffer + FFALIGN(blockstodecode, 8); + + /* get output buffer */ + frame->nb_samples = blockstodecode; + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + + s->error=0; + + if ((s->channels == 1) || (s->frameflags & APE_FRAMECODE_PSEUDO_STEREO)) + ape_unpack_mono(s, blockstodecode); + else + ape_unpack_stereo(s, blockstodecode); + emms_c(); + + if (s->error) { + s->samples=0; + av_log(avctx, AV_LOG_ERROR, "Error decoding frame\n"); + return AVERROR_INVALIDDATA; + } + + switch (s->bps) { + case 8: + for (ch = 0; ch < s->channels; ch++) { + sample8 = (uint8_t *)frame->data[ch]; + for (i = 0; i < blockstodecode; i++) + *sample8++ = (s->decoded[ch][i] + 0x80) & 0xff; + } + break; + case 16: + for (ch = 0; ch < s->channels; ch++) { + sample16 = (int16_t *)frame->data[ch]; + for (i = 0; i < blockstodecode; i++) + *sample16++ = s->decoded[ch][i]; + } + break; + case 24: + for (ch = 0; ch < s->channels; ch++) { + sample24 = (int32_t *)frame->data[ch]; + for (i = 0; i < blockstodecode; i++) + *sample24++ = s->decoded[ch][i] << 8; + } + break; + } + + s->samples -= blockstodecode; + + *got_frame_ptr = 1; + + return !s->samples ? avpkt->size : 0; +} + +static void ape_flush(AVCodecContext *avctx) +{ + APEContext *s = avctx->priv_data; + s->samples= 0; +} + +#define OFFSET(x) offsetof(APEContext, x) +#define PAR (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM) +static const AVOption options[] = { + { "max_samples", "maximum number of samples decoded per call", OFFSET(blocks_per_loop), AV_OPT_TYPE_INT, { .i64 = 4608 }, 1, INT_MAX, PAR, "max_samples" }, + { "all", "no maximum. decode all samples for each packet at once", 0, AV_OPT_TYPE_CONST, { .i64 = INT_MAX }, INT_MIN, INT_MAX, PAR, "max_samples" }, + { NULL}, +}; + +static const AVClass ape_decoder_class = { + .class_name = "APE decoder", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVCodec ff_ape_decoder = { + .name = "ape", + .type = AVMEDIA_TYPE_AUDIO, + .id = AV_CODEC_ID_APE, + .priv_data_size = sizeof(APEContext), + .init = ape_decode_init, + .close = ape_decode_close, + .decode = ape_decode_frame, + .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DELAY | CODEC_CAP_DR1, + .flush = ape_flush, + .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"), + .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_U8P, + AV_SAMPLE_FMT_S16P, + AV_SAMPLE_FMT_S32P, + AV_SAMPLE_FMT_NONE }, + .priv_class = &ape_decoder_class, +}; |