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/*
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 * FLAC (Free Lossless Audio Codec) decoder
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 * Copyright (c) 2003 Alex Beregszaszi
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file flac.c
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 * FLAC (Free Lossless Audio Codec) decoder
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 * @author Alex Beregszaszi
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 *
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 * For more information on the FLAC format, visit:
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 *  http://flac.sourceforge.net/
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 *
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 * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
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 * through, starting from the initial 'fLaC' signature; or by passing the
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 * 34-byte streaminfo structure through avctx->extradata[_size] followed
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 * by data starting with the 0xFFF8 marker.
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 */
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#include <limits.h>
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#include "avcodec.h"
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#include "bitstream.h"
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#include "golomb.h"
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#include "crc.h"
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#undef NDEBUG
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#include <assert.h>
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#define MAX_CHANNELS 8
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#define MAX_BLOCKSIZE 65535
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#define FLAC_STREAMINFO_SIZE 34
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enum decorrelation_type {
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    INDEPENDENT,
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    LEFT_SIDE,
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    RIGHT_SIDE,
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    MID_SIDE,
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};
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typedef struct FLACContext {
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    AVCodecContext *avctx;
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    GetBitContext gb;
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    int min_blocksize, max_blocksize;
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    int min_framesize, max_framesize;
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    int samplerate, channels;
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    int blocksize/*, last_blocksize*/;
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    int bps, curr_bps;
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    enum decorrelation_type decorrelation;
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    int32_t *decoded[MAX_CHANNELS];
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    uint8_t *bitstream;
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    int bitstream_size;
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    int bitstream_index;
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    unsigned int allocated_bitstream_size;
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} FLACContext;
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#define METADATA_TYPE_STREAMINFO 0
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static int sample_rate_table[] =
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{ 0, 0, 0, 0,
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  8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
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  0, 0, 0, 0 };
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static int sample_size_table[] =
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{ 0, 8, 12, 0, 16, 20, 24, 0 };
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static int blocksize_table[] = {
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     0,    192, 576<<0, 576<<1, 576<<2, 576<<3,      0,      0,
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256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
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};
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static int64_t get_utf8(GetBitContext *gb){
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    int64_t val;
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    GET_UTF8(val, get_bits(gb, 8), return -1;)
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    return val;
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}
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static void metadata_streaminfo(FLACContext *s);
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static void dump_headers(FLACContext *s);
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static int flac_decode_init(AVCodecContext * avctx)
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{
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    FLACContext *s = avctx->priv_data;
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    s->avctx = avctx;
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    /* initialize based on the demuxer-supplied streamdata header */
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    if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
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        init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
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        metadata_streaminfo(s);
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        dump_headers(s);
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    }
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    return 0;
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}
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static void dump_headers(FLACContext *s)
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{
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    av_log(s->avctx, AV_LOG_DEBUG, "  Blocksize: %d .. %d (%d)\n", s->min_blocksize, s->max_blocksize, s->blocksize);
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    av_log(s->avctx, AV_LOG_DEBUG, "  Framesize: %d .. %d\n", s->min_framesize, s->max_framesize);
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    av_log(s->avctx, AV_LOG_DEBUG, "  Samplerate: %d\n", s->samplerate);
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    av_log(s->avctx, AV_LOG_DEBUG, "  Channels: %d\n", s->channels);
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    av_log(s->avctx, AV_LOG_DEBUG, "  Bits: %d\n", s->bps);
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}
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static void allocate_buffers(FLACContext *s){
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    int i;
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    assert(s->max_blocksize);
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    if(s->max_framesize == 0 && s->max_blocksize){
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        s->max_framesize= (s->channels * s->bps * s->max_blocksize + 7)/ 8; //FIXME header overhead
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    }
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    for (i = 0; i < s->channels; i++)
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    {
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        s->decoded[i] = av_realloc(s->decoded[i], sizeof(int32_t)*s->max_blocksize);
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    }
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    s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
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}
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static void metadata_streaminfo(FLACContext *s)
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{
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    /* mandatory streaminfo */
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    s->min_blocksize = get_bits(&s->gb, 16);
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    s->max_blocksize = get_bits(&s->gb, 16);
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    s->min_framesize = get_bits_long(&s->gb, 24);
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    s->max_framesize = get_bits_long(&s->gb, 24);
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    s->samplerate = get_bits_long(&s->gb, 20);
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    s->channels = get_bits(&s->gb, 3) + 1;
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    s->bps = get_bits(&s->gb, 5) + 1;
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    s->avctx->channels = s->channels;
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    s->avctx->sample_rate = s->samplerate;
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    skip_bits(&s->gb, 36); /* total num of samples */
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    skip_bits(&s->gb, 64); /* md5 sum */
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    skip_bits(&s->gb, 64); /* md5 sum */
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    allocate_buffers(s);
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}
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static int decode_residuals(FLACContext *s, int channel, int pred_order)
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{
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    int i, tmp, partition, method_type, rice_order;
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    int sample = 0, samples;
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    method_type = get_bits(&s->gb, 2);
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    if (method_type != 0){
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        av_log(s->avctx, AV_LOG_DEBUG, "illegal residual coding method %d\n", method_type);
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        return -1;
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    }
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    rice_order = get_bits(&s->gb, 4);
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    samples= s->blocksize >> rice_order;
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    sample=
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    i= pred_order;
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    for (partition = 0; partition < (1 << rice_order); partition++)
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    {
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        tmp = get_bits(&s->gb, 4);
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        if (tmp == 15)
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        {
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            av_log(s->avctx, AV_LOG_DEBUG, "fixed len partition\n");
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            tmp = get_bits(&s->gb, 5);
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            for (; i < samples; i++, sample++)
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                s->decoded[channel][sample] = get_sbits(&s->gb, tmp);
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        }
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        else
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        {
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//            av_log(s->avctx, AV_LOG_DEBUG, "rice coded partition k=%d\n", tmp);
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            for (; i < samples; i++, sample++){
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                s->decoded[channel][sample] = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
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            }
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        }
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        i= 0;
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    }
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//    av_log(s->avctx, AV_LOG_DEBUG, "partitions: %d, samples: %d\n", 1 << rice_order, sample);
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    return 0;
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}
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static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
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{
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    int i;
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//    av_log(s->avctx, AV_LOG_DEBUG, "  SUBFRAME FIXED\n");
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    /* warm up samples */
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//    av_log(s->avctx, AV_LOG_DEBUG, "   warm up samples: %d\n", pred_order);
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    for (i = 0; i < pred_order; i++)
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    {
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        s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
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//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, s->decoded[channel][i]);
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    }
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    if (decode_residuals(s, channel, pred_order) < 0)
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        return -1;
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    switch(pred_order)
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    {
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        case 0:
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            break;
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        case 1:
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            for (i = pred_order; i < s->blocksize; i++)
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                s->decoded[channel][i] +=   s->decoded[channel][i-1];
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            break;
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        case 2:
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            for (i = pred_order; i < s->blocksize; i++)
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                s->decoded[channel][i] += 2*s->decoded[channel][i-1]
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                                          - s->decoded[channel][i-2];
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            break;
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        case 3:
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            for (i = pred_order; i < s->blocksize; i++)
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                s->decoded[channel][i] += 3*s->decoded[channel][i-1]
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                                        - 3*s->decoded[channel][i-2]
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                                        +   s->decoded[channel][i-3];
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            break;
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        case 4:
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            for (i = pred_order; i < s->blocksize; i++)
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                s->decoded[channel][i] += 4*s->decoded[channel][i-1]
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                                        - 6*s->decoded[channel][i-2]
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                                        + 4*s->decoded[channel][i-3]
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                                        -   s->decoded[channel][i-4];
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            break;
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        default:
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            av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order);
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            return -1;
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    }
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    return 0;
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}
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static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
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{
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    int i, j;
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    int coeff_prec, qlevel;
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    int coeffs[pred_order];
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//    av_log(s->avctx, AV_LOG_DEBUG, "  SUBFRAME LPC\n");
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    /* warm up samples */
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//    av_log(s->avctx, AV_LOG_DEBUG, "   warm up samples: %d\n", pred_order);
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    for (i = 0; i < pred_order; i++)
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    {
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        s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
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//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, s->decoded[channel][i]);
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    }
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    coeff_prec = get_bits(&s->gb, 4) + 1;
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    if (coeff_prec == 16)
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    {
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        av_log(s->avctx, AV_LOG_DEBUG, "invalid coeff precision\n");
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        return -1;
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    }
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//    av_log(s->avctx, AV_LOG_DEBUG, "   qlp coeff prec: %d\n", coeff_prec);
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    qlevel = get_sbits(&s->gb, 5);
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//    av_log(s->avctx, AV_LOG_DEBUG, "   quant level: %d\n", qlevel);
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    if(qlevel < 0){
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        av_log(s->avctx, AV_LOG_DEBUG, "qlevel %d not supported, maybe buggy stream\n", qlevel);
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        return -1;
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    }
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    for (i = 0; i < pred_order; i++)
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    {
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        coeffs[i] = get_sbits(&s->gb, coeff_prec);
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//        av_log(s->avctx, AV_LOG_DEBUG, "    %d: %d\n", i, coeffs[i]);
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    }
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    if (decode_residuals(s, channel, pred_order) < 0)
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        return -1;
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    if (s->bps > 16) {
297
        int64_t sum;
298
        for (i = pred_order; i < s->blocksize; i++)
299
        {
300
            sum = 0;
301
            for (j = 0; j < pred_order; j++)
302
                sum += (int64_t)coeffs[j] * s->decoded[channel][i-j-1];
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            s->decoded[channel][i] += sum >> qlevel;
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        }
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    } else {
306
        int sum;
307
        for (i = pred_order; i < s->blocksize; i++)
308
        {
309
            sum = 0;
310
            for (j = 0; j < pred_order; j++)
311
                sum += coeffs[j] * s->decoded[channel][i-j-1];
312
            s->decoded[channel][i] += sum >> qlevel;
313
        }
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    }
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    return 0;
317
}
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static inline int decode_subframe(FLACContext *s, int channel)
320
{
321
    int type, wasted = 0;
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    int i, tmp;
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    s->curr_bps = s->bps;
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    if(channel == 0){
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        if(s->decorrelation == RIGHT_SIDE)
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            s->curr_bps++;
328
    }else{
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        if(s->decorrelation == LEFT_SIDE || s->decorrelation == MID_SIDE)
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            s->curr_bps++;
331
    }
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    if (get_bits1(&s->gb))
334
    {
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        av_log(s->avctx, AV_LOG_ERROR, "invalid subframe padding\n");
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        return -1;
337
    }
338
    type = get_bits(&s->gb, 6);
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//    wasted = get_bits1(&s->gb);
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//    if (wasted)
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//    {
343
//        while (!get_bits1(&s->gb))
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//            wasted++;
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//        if (wasted)
346
//            wasted++;
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//        s->curr_bps -= wasted;
348
//    }
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#if 0
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    wasted= 16 - av_log2(show_bits(&s->gb, 17));
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    skip_bits(&s->gb, wasted+1);
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    s->curr_bps -= wasted;
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#else
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    if (get_bits1(&s->gb))
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    {
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        wasted = 1;
357
        while (!get_bits1(&s->gb))
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            wasted++;
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        s->curr_bps -= wasted;
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        av_log(s->avctx, AV_LOG_DEBUG, "%d wasted bits\n", wasted);
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    }
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#endif
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//FIXME use av_log2 for types
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    if (type == 0)
365
    {
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        av_log(s->avctx, AV_LOG_DEBUG, "coding type: constant\n");
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        tmp = get_sbits(&s->gb, s->curr_bps);
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        for (i = 0; i < s->blocksize; i++)
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            s->decoded[channel][i] = tmp;
370
    }
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    else if (type == 1)
372
    {
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        av_log(s->avctx, AV_LOG_DEBUG, "coding type: verbatim\n");
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        for (i = 0; i < s->blocksize; i++)
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            s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
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    }
377
    else if ((type >= 8) && (type <= 12))
378
    {
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//        av_log(s->avctx, AV_LOG_DEBUG, "coding type: fixed\n");
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        if (decode_subframe_fixed(s, channel, type & ~0x8) < 0)
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            return -1;
382
    }
383
    else if (type >= 32)
384
    {
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//        av_log(s->avctx, AV_LOG_DEBUG, "coding type: lpc\n");
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        if (decode_subframe_lpc(s, channel, (type & ~0x20)+1) < 0)
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            return -1;
388
    }
389
    else
390
    {
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        av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n");
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        return -1;
393
    }
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    if (wasted)
396
    {
397
        int i;
398
        for (i = 0; i < s->blocksize; i++)
399
            s->decoded[channel][i] <<= wasted;
400
    }
401
402
    return 0;
403
}
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405
static int decode_frame(FLACContext *s)
406
{
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    int blocksize_code, sample_rate_code, sample_size_code, assignment, i, crc8;
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    int decorrelation, bps, blocksize, samplerate;
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    blocksize_code = get_bits(&s->gb, 4);
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    sample_rate_code = get_bits(&s->gb, 4);
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    assignment = get_bits(&s->gb, 4); /* channel assignment */
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    if (assignment < 8 && s->channels == assignment+1)
416
        decorrelation = INDEPENDENT;
417
    else if (assignment >=8 && assignment < 11 && s->channels == 2)
418
        decorrelation = LEFT_SIDE + assignment - 8;
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    else
420
    {
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        av_log(s->avctx, AV_LOG_ERROR, "unsupported channel assignment %d (channels=%d)\n", assignment, s->channels);
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        return -1;
423
    }
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    sample_size_code = get_bits(&s->gb, 3);
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    if(sample_size_code == 0)
427
        bps= s->bps;
428
    else if((sample_size_code != 3) && (sample_size_code != 7))
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        bps = sample_size_table[sample_size_code];
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    else
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    {
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        av_log(s->avctx, AV_LOG_ERROR, "invalid sample size code (%d)\n", sample_size_code);
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        return -1;
434
    }
435
436
    if (get_bits1(&s->gb))
437
    {
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        av_log(s->avctx, AV_LOG_ERROR, "broken stream, invalid padding\n");
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        return -1;
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    }
441 115329f1 Diego Biurrun
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    if(get_utf8(&s->gb) < 0){
443
        av_log(s->avctx, AV_LOG_ERROR, "utf8 fscked\n");
444
        return -1;
445
    }
446 115329f1 Diego Biurrun
#if 0
447 ac2570a8 Michael Niedermayer
    if (/*((blocksize_code == 6) || (blocksize_code == 7)) &&*/
448
        (s->min_blocksize != s->max_blocksize)){
449
    }else{
450 4f52c312 Michael Niedermayer
    }
451 0496a034 Michael Niedermayer
#endif
452 115329f1 Diego Biurrun
453 ac2570a8 Michael Niedermayer
    if (blocksize_code == 0)
454 0496a034 Michael Niedermayer
        blocksize = s->min_blocksize;
455 ac2570a8 Michael Niedermayer
    else if (blocksize_code == 6)
456 0496a034 Michael Niedermayer
        blocksize = get_bits(&s->gb, 8)+1;
457 ac2570a8 Michael Niedermayer
    else if (blocksize_code == 7)
458 0496a034 Michael Niedermayer
        blocksize = get_bits(&s->gb, 16)+1;
459 115329f1 Diego Biurrun
    else
460 0496a034 Michael Niedermayer
        blocksize = blocksize_table[blocksize_code];
461 4f52c312 Michael Niedermayer
462 0496a034 Michael Niedermayer
    if(blocksize > s->max_blocksize){
463
        av_log(s->avctx, AV_LOG_ERROR, "blocksize %d > %d\n", blocksize, s->max_blocksize);
464 ac2570a8 Michael Niedermayer
        return -1;
465
    }
466
467
    if (sample_rate_code == 0){
468 0496a034 Michael Niedermayer
        samplerate= s->samplerate;
469 ac2570a8 Michael Niedermayer
    }else if ((sample_rate_code > 3) && (sample_rate_code < 12))
470 0496a034 Michael Niedermayer
        samplerate = sample_rate_table[sample_rate_code];
471 ac2570a8 Michael Niedermayer
    else if (sample_rate_code == 12)
472 0496a034 Michael Niedermayer
        samplerate = get_bits(&s->gb, 8) * 1000;
473 ac2570a8 Michael Niedermayer
    else if (sample_rate_code == 13)
474 0496a034 Michael Niedermayer
        samplerate = get_bits(&s->gb, 16);
475 ac2570a8 Michael Niedermayer
    else if (sample_rate_code == 14)
476 0496a034 Michael Niedermayer
        samplerate = get_bits(&s->gb, 16) * 10;
477 ac2570a8 Michael Niedermayer
    else{
478
        av_log(s->avctx, AV_LOG_ERROR, "illegal sample rate code %d\n", sample_rate_code);
479
        return -1;
480 4f52c312 Michael Niedermayer
    }
481
482 9d656110 Michael Niedermayer
    skip_bits(&s->gb, 8);
483 b865838e Michael Niedermayer
    crc8= av_crc(av_crc07, 0, s->gb.buffer, get_bits_count(&s->gb)/8);
484 9d656110 Michael Niedermayer
    if(crc8){
485 160d679c Mike Melanson
        av_log(s->avctx, AV_LOG_ERROR, "header crc mismatch crc=%2X\n", crc8);
486 9d656110 Michael Niedermayer
        return -1;
487
    }
488 115329f1 Diego Biurrun
489 0496a034 Michael Niedermayer
    s->blocksize    = blocksize;
490
    s->samplerate   = samplerate;
491
    s->bps          = bps;
492
    s->decorrelation= decorrelation;
493 4f52c312 Michael Niedermayer
494 ac2570a8 Michael Niedermayer
//    dump_headers(s);
495 4f52c312 Michael Niedermayer
496
    /* subframes */
497
    for (i = 0; i < s->channels; i++)
498
    {
499 ac2570a8 Michael Niedermayer
//        av_log(s->avctx, AV_LOG_DEBUG, "decoded: %x residual: %x\n", s->decoded[i], s->residual[i]);
500 4f52c312 Michael Niedermayer
        if (decode_subframe(s, i) < 0)
501
            return -1;
502
    }
503 115329f1 Diego Biurrun
504 4f52c312 Michael Niedermayer
    align_get_bits(&s->gb);
505
506
    /* frame footer */
507
    skip_bits(&s->gb, 16); /* data crc */
508
509
    return 0;
510
}
511
512 0187178e Luca Barbato
static inline int16_t shift_to_16_bits(int32_t data, int bps)
513
{
514
    if (bps == 24) {
515
        return (data >> 8);
516
    } else if (bps == 20) {
517
        return (data >> 4);
518
    } else {
519
        return data;
520
    }
521
}
522
523 4f52c312 Michael Niedermayer
static int flac_decode_frame(AVCodecContext *avctx,
524
                            void *data, int *data_size,
525
                            uint8_t *buf, int buf_size)
526
{
527
    FLACContext *s = avctx->priv_data;
528 ac2570a8 Michael Niedermayer
    int metadata_last, metadata_type, metadata_size;
529 3f1899a8 Mike Melanson
    int tmp = 0, i, j = 0, input_buf_size = 0;
530
    int16_t *samples = data;
531 4f52c312 Michael Niedermayer
532 ac2570a8 Michael Niedermayer
    if(s->max_framesize == 0){
533 09f20d37 Loren Merritt
        s->max_framesize= 65536; // should hopefully be enough for the first header
534 ac2570a8 Michael Niedermayer
        s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
535
    }
536
537
    if(1 && s->max_framesize){//FIXME truncated
538 09f20d37 Loren Merritt
            buf_size= FFMAX(FFMIN(buf_size, s->max_framesize - s->bitstream_size), 0);
539 ac2570a8 Michael Niedermayer
            input_buf_size= buf_size;
540
541
            if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
542
//                printf("memmove\n");
543
                memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
544
                s->bitstream_index=0;
545
            }
546
            memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
547
            buf= &s->bitstream[s->bitstream_index];
548
            buf_size += s->bitstream_size;
549
            s->bitstream_size= buf_size;
550 115329f1 Diego Biurrun
551 ac2570a8 Michael Niedermayer
            if(buf_size < s->max_framesize){
552
//                printf("wanna more data ...\n");
553
                return input_buf_size;
554
            }
555
    }
556 4f52c312 Michael Niedermayer
557
    init_get_bits(&s->gb, buf, buf_size*8);
558 115329f1 Diego Biurrun
559 4f52c312 Michael Niedermayer
    /* fLaC signature (be) */
560 ac2570a8 Michael Niedermayer
    if (show_bits_long(&s->gb, 32) == bswap_32(ff_get_fourcc("fLaC")))
561 4f52c312 Michael Niedermayer
    {
562 ac2570a8 Michael Niedermayer
        skip_bits(&s->gb, 32);
563
564
        av_log(s->avctx, AV_LOG_DEBUG, "STREAM HEADER\n");
565 4f52c312 Michael Niedermayer
        do {
566 ac2570a8 Michael Niedermayer
            metadata_last = get_bits(&s->gb, 1);
567 4f52c312 Michael Niedermayer
            metadata_type = get_bits(&s->gb, 7);
568
            metadata_size = get_bits_long(&s->gb, 24);
569 115329f1 Diego Biurrun
570 ac2570a8 Michael Niedermayer
            av_log(s->avctx, AV_LOG_DEBUG, " metadata block: flag = %d, type = %d, size = %d\n",
571
                metadata_last, metadata_type,
572 4f52c312 Michael Niedermayer
                metadata_size);
573 ac2570a8 Michael Niedermayer
            if(metadata_size){
574
                switch(metadata_type)
575
                {
576 db2fcbbd Michael Niedermayer
                case METADATA_TYPE_STREAMINFO:{
577 4f52c312 Michael Niedermayer
                    metadata_streaminfo(s);
578 db2fcbbd Michael Niedermayer
579 56b31a8e Loren Merritt
                    /* Buffer might have been reallocated, reinit bitreader */
580
                    if(buf != &s->bitstream[s->bitstream_index])
581
                    {
582
                        int bits_count = get_bits_count(&s->gb);
583
                        buf= &s->bitstream[s->bitstream_index];
584
                        init_get_bits(&s->gb, buf, buf_size*8);
585
                        skip_bits(&s->gb, bits_count);
586
                    }
587 115329f1 Diego Biurrun
588 4f52c312 Michael Niedermayer
                    dump_headers(s);
589 db2fcbbd Michael Niedermayer
                    break;}
590 4f52c312 Michael Niedermayer
                default:
591 ac2570a8 Michael Niedermayer
                    for(i=0; i<metadata_size; i++)
592 4f52c312 Michael Niedermayer
                        skip_bits(&s->gb, 8);
593 ac2570a8 Michael Niedermayer
                }
594 4f52c312 Michael Niedermayer
            }
595 ac2570a8 Michael Niedermayer
        } while(!metadata_last);
596 4f52c312 Michael Niedermayer
    }
597
    else
598
    {
599 115329f1 Diego Biurrun
600 9d656110 Michael Niedermayer
        tmp = show_bits(&s->gb, 16);
601 ac2570a8 Michael Niedermayer
        if(tmp != 0xFFF8){
602
            av_log(s->avctx, AV_LOG_ERROR, "FRAME HEADER not here\n");
603
            while(get_bits_count(&s->gb)/8+2 < buf_size && show_bits(&s->gb, 16) != 0xFFF8)
604
                skip_bits(&s->gb, 8);
605
            goto end; // we may not have enough bits left to decode a frame, so try next time
606
        }
607
        skip_bits(&s->gb, 16);
608 9d656110 Michael Niedermayer
        if (decode_frame(s) < 0){
609
            av_log(s->avctx, AV_LOG_ERROR, "decode_frame() failed\n");
610
            s->bitstream_size=0;
611
            s->bitstream_index=0;
612 4f52c312 Michael Niedermayer
            return -1;
613 9d656110 Michael Niedermayer
        }
614 4f52c312 Michael Niedermayer
    }
615 ac2570a8 Michael Niedermayer
616 115329f1 Diego Biurrun
617 4f52c312 Michael Niedermayer
#if 0
618
    /* fix the channel order here */
619
    if (s->order == MID_SIDE)
620
    {
621
        short *left = samples;
622
        short *right = samples + s->blocksize;
623
        for (i = 0; i < s->blocksize; i += 2)
624
        {
625
            uint32_t x = s->decoded[0][i];
626
            uint32_t y = s->decoded[0][i+1];
627

628
            right[i] = x - (y / 2);
629
            left[i] = right[i] + y;
630
        }
631
        *data_size = 2 * s->blocksize;
632
    }
633
    else
634
    {
635
    for (i = 0; i < s->channels; i++)
636
    {
637
        switch(s->order)
638
        {
639
            case INDEPENDENT:
640
                for (j = 0; j < s->blocksize; j++)
641
                    samples[(s->blocksize*i)+j] = s->decoded[i][j];
642
                break;
643
            case LEFT_SIDE:
644
            case RIGHT_SIDE:
645
                if (i == 0)
646
                    for (j = 0; j < s->blocksize; j++)
647
                        samples[(s->blocksize*i)+j] = s->decoded[0][j];
648
                else
649
                    for (j = 0; j < s->blocksize; j++)
650
                        samples[(s->blocksize*i)+j] = s->decoded[0][j] - s->decoded[i][j];
651
                break;
652
//            case MID_SIDE:
653 ac2570a8 Michael Niedermayer
//                av_log(s->avctx, AV_LOG_DEBUG, "mid-side unsupported\n");
654 4f52c312 Michael Niedermayer
        }
655
        *data_size += s->blocksize;
656
    }
657
    }
658
#else
659 c448303d Michael Niedermayer
#define DECORRELATE(left, right)\
660
            assert(s->channels == 2);\
661
            for (i = 0; i < s->blocksize; i++)\
662
            {\
663
                int a= s->decoded[0][i];\
664
                int b= s->decoded[1][i];\
665
                *(samples++) = (left ) >> (16 - s->bps);\
666
                *(samples++) = (right) >> (16 - s->bps);\
667
            }\
668
            break;
669
670 9d656110 Michael Niedermayer
    switch(s->decorrelation)
671 4f52c312 Michael Niedermayer
    {
672
        case INDEPENDENT:
673 ac2570a8 Michael Niedermayer
            for (j = 0; j < s->blocksize; j++)
674 4f52c312 Michael Niedermayer
            {
675 ac2570a8 Michael Niedermayer
                for (i = 0; i < s->channels; i++)
676 0187178e Luca Barbato
                    *(samples++) = shift_to_16_bits(s->decoded[i][j], s->bps);
677 4f52c312 Michael Niedermayer
            }
678
            break;
679
        case LEFT_SIDE:
680 c448303d Michael Niedermayer
            DECORRELATE(a,a-b)
681 4f52c312 Michael Niedermayer
        case RIGHT_SIDE:
682 c448303d Michael Niedermayer
            DECORRELATE(a+b,b)
683 4f52c312 Michael Niedermayer
        case MID_SIDE:
684 c448303d Michael Niedermayer
            DECORRELATE( (a-=b>>1) + b, a)
685 4f52c312 Michael Niedermayer
    }
686
#endif
687
688 ac2570a8 Michael Niedermayer
    *data_size = (int8_t *)samples - (int8_t *)data;
689 9d656110 Michael Niedermayer
//    av_log(s->avctx, AV_LOG_DEBUG, "data size: %d\n", *data_size);
690 4f52c312 Michael Niedermayer
691 ac2570a8 Michael Niedermayer
//    s->last_blocksize = s->blocksize;
692
end:
693
    i= (get_bits_count(&s->gb)+7)/8;;
694
    if(i > buf_size){
695
        av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
696 9d656110 Michael Niedermayer
        s->bitstream_size=0;
697
        s->bitstream_index=0;
698 ac2570a8 Michael Niedermayer
        return -1;
699
    }
700 4f52c312 Michael Niedermayer
701 ac2570a8 Michael Niedermayer
    if(s->bitstream_size){
702
        s->bitstream_index += i;
703
        s->bitstream_size  -= i;
704
        return input_buf_size;
705 115329f1 Diego Biurrun
    }else
706 ac2570a8 Michael Niedermayer
        return i;
707 4f52c312 Michael Niedermayer
}
708
709
static int flac_decode_close(AVCodecContext *avctx)
710
{
711
    FLACContext *s = avctx->priv_data;
712
    int i;
713 115329f1 Diego Biurrun
714 4f52c312 Michael Niedermayer
    for (i = 0; i < s->channels; i++)
715
    {
716 ac2570a8 Michael Niedermayer
        av_freep(&s->decoded[i]);
717 4f52c312 Michael Niedermayer
    }
718 ac2570a8 Michael Niedermayer
    av_freep(&s->bitstream);
719 115329f1 Diego Biurrun
720 4f52c312 Michael Niedermayer
    return 0;
721
}
722
723 1e31d32c Michael Niedermayer
static void flac_flush(AVCodecContext *avctx){
724
    FLACContext *s = avctx->priv_data;
725
726
    s->bitstream_size=
727
    s->bitstream_index= 0;
728
}
729
730 4f52c312 Michael Niedermayer
AVCodec flac_decoder = {
731
    "flac",
732
    CODEC_TYPE_AUDIO,
733
    CODEC_ID_FLAC,
734
    sizeof(FLACContext),
735
    flac_decode_init,
736
    NULL,
737
    flac_decode_close,
738
    flac_decode_frame,
739 115329f1 Diego Biurrun
    .flush= flac_flush,
740 4f52c312 Michael Niedermayer
};