yading@10: /*
yading@10:  * FLAC (Free Lossless Audio Codec) decoder
yading@10:  * Copyright (c) 2003 Alex Beregszaszi
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * FLAC (Free Lossless Audio Codec) decoder
yading@10:  * @author Alex Beregszaszi
yading@10:  * @see http://flac.sourceforge.net/
yading@10:  *
yading@10:  * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
yading@10:  * through, starting from the initial 'fLaC' signature; or by passing the
yading@10:  * 34-byte streaminfo structure through avctx->extradata[_size] followed
yading@10:  * by data starting with the 0xFFF8 marker.
yading@10:  */
yading@10: 
yading@10: #include <limits.h>
yading@10: 
yading@10: #include "libavutil/avassert.h"
yading@10: #include "libavutil/channel_layout.h"
yading@10: #include "libavutil/crc.h"
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: #include "get_bits.h"
yading@10: #include "bytestream.h"
yading@10: #include "golomb.h"
yading@10: #include "flac.h"
yading@10: #include "flacdata.h"
yading@10: #include "flacdsp.h"
yading@10: 
yading@10: typedef struct FLACContext {
yading@10:     FLACSTREAMINFO
yading@10: 
yading@10:     AVCodecContext *avctx;                  ///< parent AVCodecContext
yading@10:     GetBitContext gb;                       ///< GetBitContext initialized to start at the current frame
yading@10: 
yading@10:     int blocksize;                          ///< number of samples in the current frame
yading@10:     int sample_shift;                       ///< shift required to make output samples 16-bit or 32-bit
yading@10:     int ch_mode;                            ///< channel decorrelation type in the current frame
yading@10:     int got_streaminfo;                     ///< indicates if the STREAMINFO has been read
yading@10: 
yading@10:     int32_t *decoded[FLAC_MAX_CHANNELS];    ///< decoded samples
yading@10:     uint8_t *decoded_buffer;
yading@10:     unsigned int decoded_buffer_size;
yading@10: 
yading@10:     FLACDSPContext dsp;
yading@10: } FLACContext;
yading@10: 
yading@10: static int allocate_buffers(FLACContext *s);
yading@10: 
yading@10: static void flac_set_bps(FLACContext *s)
yading@10: {
yading@10:     enum AVSampleFormat req = s->avctx->request_sample_fmt;
yading@10:     int need32 = s->bps > 16;
yading@10:     int want32 = av_get_bytes_per_sample(req) > 2;
yading@10:     int planar = av_sample_fmt_is_planar(req);
yading@10: 
yading@10:     if (need32 || want32) {
yading@10:         if (planar)
yading@10:             s->avctx->sample_fmt = AV_SAMPLE_FMT_S32P;
yading@10:         else
yading@10:             s->avctx->sample_fmt = AV_SAMPLE_FMT_S32;
yading@10:         s->sample_shift = 32 - s->bps;
yading@10:     } else {
yading@10:         if (planar)
yading@10:             s->avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
yading@10:         else
yading@10:             s->avctx->sample_fmt = AV_SAMPLE_FMT_S16;
yading@10:         s->sample_shift = 16 - s->bps;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static av_cold int flac_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     enum FLACExtradataFormat format;
yading@10:     uint8_t *streaminfo;
yading@10:     int ret;
yading@10:     FLACContext *s = avctx->priv_data;
yading@10:     s->avctx = avctx;
yading@10: 
yading@10:     /* for now, the raw FLAC header is allowed to be passed to the decoder as
yading@10:        frame data instead of extradata. */
yading@10:     if (!avctx->extradata)
yading@10:         return 0;
yading@10: 
yading@10:     if (!avpriv_flac_is_extradata_valid(avctx, &format, &streaminfo))
yading@10:         return AVERROR_INVALIDDATA;
yading@10: 
yading@10:     /* initialize based on the demuxer-supplied streamdata header */
yading@10:     avpriv_flac_parse_streaminfo(avctx, (FLACStreaminfo *)s, streaminfo);
yading@10:     ret = allocate_buffers(s);
yading@10:     if (ret < 0)
yading@10:         return ret;
yading@10:     flac_set_bps(s);
yading@10:     ff_flacdsp_init(&s->dsp, avctx->sample_fmt, s->bps);
yading@10:     s->got_streaminfo = 1;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static void dump_headers(AVCodecContext *avctx, FLACStreaminfo *s)
yading@10: {
yading@10:     av_log(avctx, AV_LOG_DEBUG, "  Max Blocksize: %d\n", s->max_blocksize);
yading@10:     av_log(avctx, AV_LOG_DEBUG, "  Max Framesize: %d\n", s->max_framesize);
yading@10:     av_log(avctx, AV_LOG_DEBUG, "  Samplerate: %d\n", s->samplerate);
yading@10:     av_log(avctx, AV_LOG_DEBUG, "  Channels: %d\n", s->channels);
yading@10:     av_log(avctx, AV_LOG_DEBUG, "  Bits: %d\n", s->bps);
yading@10: }
yading@10: 
yading@10: static int allocate_buffers(FLACContext *s)
yading@10: {
yading@10:     int buf_size;
yading@10: 
yading@10:     av_assert0(s->max_blocksize);
yading@10: 
yading@10:     buf_size = av_samples_get_buffer_size(NULL, s->channels, s->max_blocksize,
yading@10:                                           AV_SAMPLE_FMT_S32P, 0);
yading@10:     if (buf_size < 0)
yading@10:         return buf_size;
yading@10: 
yading@10:     av_fast_malloc(&s->decoded_buffer, &s->decoded_buffer_size, buf_size);
yading@10:     if (!s->decoded_buffer)
yading@10:         return AVERROR(ENOMEM);
yading@10: 
yading@10:     return av_samples_fill_arrays((uint8_t **)s->decoded, NULL,
yading@10:                                   s->decoded_buffer, s->channels,
yading@10:                                   s->max_blocksize, AV_SAMPLE_FMT_S32P, 0);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Parse the STREAMINFO from an inline header.
yading@10:  * @param s the flac decoding context
yading@10:  * @param buf input buffer, starting with the "fLaC" marker
yading@10:  * @param buf_size buffer size
yading@10:  * @return non-zero if metadata is invalid
yading@10:  */
yading@10: static int parse_streaminfo(FLACContext *s, const uint8_t *buf, int buf_size)
yading@10: {
yading@10:     int metadata_type, metadata_size, ret;
yading@10: 
yading@10:     if (buf_size < FLAC_STREAMINFO_SIZE+8) {
yading@10:         /* need more data */
yading@10:         return 0;
yading@10:     }
yading@10:     avpriv_flac_parse_block_header(&buf[4], NULL, &metadata_type, &metadata_size);
yading@10:     if (metadata_type != FLAC_METADATA_TYPE_STREAMINFO ||
yading@10:         metadata_size != FLAC_STREAMINFO_SIZE) {
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     avpriv_flac_parse_streaminfo(s->avctx, (FLACStreaminfo *)s, &buf[8]);
yading@10:     ret = allocate_buffers(s);
yading@10:     if (ret < 0)
yading@10:         return ret;
yading@10:     flac_set_bps(s);
yading@10:     ff_flacdsp_init(&s->dsp, s->avctx->sample_fmt, s->bps);
yading@10:     s->got_streaminfo = 1;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Determine the size of an inline header.
yading@10:  * @param buf input buffer, starting with the "fLaC" marker
yading@10:  * @param buf_size buffer size
yading@10:  * @return number of bytes in the header, or 0 if more data is needed
yading@10:  */
yading@10: static int get_metadata_size(const uint8_t *buf, int buf_size)
yading@10: {
yading@10:     int metadata_last, metadata_size;
yading@10:     const uint8_t *buf_end = buf + buf_size;
yading@10: 
yading@10:     buf += 4;
yading@10:     do {
yading@10:         if (buf_end - buf < 4)
yading@10:             return 0;
yading@10:         avpriv_flac_parse_block_header(buf, &metadata_last, NULL, &metadata_size);
yading@10:         buf += 4;
yading@10:         if (buf_end - buf < metadata_size) {
yading@10:             /* need more data in order to read the complete header */
yading@10:             return 0;
yading@10:         }
yading@10:         buf += metadata_size;
yading@10:     } while (!metadata_last);
yading@10: 
yading@10:     return buf_size - (buf_end - buf);
yading@10: }
yading@10: 
yading@10: static int decode_residuals(FLACContext *s, int32_t *decoded, int pred_order)
yading@10: {
yading@10:     int i, tmp, partition, method_type, rice_order;
yading@10:     int rice_bits, rice_esc;
yading@10:     int samples;
yading@10: 
yading@10:     method_type = get_bits(&s->gb, 2);
yading@10:     if (method_type > 1) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "illegal residual coding method %d\n",
yading@10:                method_type);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     rice_order = get_bits(&s->gb, 4);
yading@10: 
yading@10:     samples= s->blocksize >> rice_order;
yading@10:     if (pred_order > samples) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid predictor order: %i > %i\n",
yading@10:                pred_order, samples);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     rice_bits = 4 + method_type;
yading@10:     rice_esc  = (1 << rice_bits) - 1;
yading@10: 
yading@10:     decoded += pred_order;
yading@10:     i= pred_order;
yading@10:     for (partition = 0; partition < (1 << rice_order); partition++) {
yading@10:         tmp = get_bits(&s->gb, rice_bits);
yading@10:         if (tmp == rice_esc) {
yading@10:             tmp = get_bits(&s->gb, 5);
yading@10:             for (; i < samples; i++)
yading@10:                 *decoded++ = get_sbits_long(&s->gb, tmp);
yading@10:         } else {
yading@10:             for (; i < samples; i++) {
yading@10:                 *decoded++ = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
yading@10:             }
yading@10:         }
yading@10:         i= 0;
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_subframe_fixed(FLACContext *s, int32_t *decoded,
yading@10:                                  int pred_order, int bps)
yading@10: {
yading@10:     const int blocksize = s->blocksize;
yading@10:     int av_uninit(a), av_uninit(b), av_uninit(c), av_uninit(d), i;
yading@10:     int ret;
yading@10: 
yading@10:     /* warm up samples */
yading@10:     for (i = 0; i < pred_order; i++) {
yading@10:         decoded[i] = get_sbits_long(&s->gb, bps);
yading@10:     }
yading@10: 
yading@10:     if ((ret = decode_residuals(s, decoded, pred_order)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     if (pred_order > 0)
yading@10:         a = decoded[pred_order-1];
yading@10:     if (pred_order > 1)
yading@10:         b = a - decoded[pred_order-2];
yading@10:     if (pred_order > 2)
yading@10:         c = b - decoded[pred_order-2] + decoded[pred_order-3];
yading@10:     if (pred_order > 3)
yading@10:         d = c - decoded[pred_order-2] + 2*decoded[pred_order-3] - decoded[pred_order-4];
yading@10: 
yading@10:     switch (pred_order) {
yading@10:     case 0:
yading@10:         break;
yading@10:     case 1:
yading@10:         for (i = pred_order; i < blocksize; i++)
yading@10:             decoded[i] = a += decoded[i];
yading@10:         break;
yading@10:     case 2:
yading@10:         for (i = pred_order; i < blocksize; i++)
yading@10:             decoded[i] = a += b += decoded[i];
yading@10:         break;
yading@10:     case 3:
yading@10:         for (i = pred_order; i < blocksize; i++)
yading@10:             decoded[i] = a += b += c += decoded[i];
yading@10:         break;
yading@10:     case 4:
yading@10:         for (i = pred_order; i < blocksize; i++)
yading@10:             decoded[i] = a += b += c += d += decoded[i];
yading@10:         break;
yading@10:     default:
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_subframe_lpc(FLACContext *s, int32_t *decoded, int pred_order,
yading@10:                                int bps)
yading@10: {
yading@10:     int i, ret;
yading@10:     int coeff_prec, qlevel;
yading@10:     int coeffs[32];
yading@10: 
yading@10:     /* warm up samples */
yading@10:     for (i = 0; i < pred_order; i++) {
yading@10:         decoded[i] = get_sbits_long(&s->gb, bps);
yading@10:     }
yading@10: 
yading@10:     coeff_prec = get_bits(&s->gb, 4) + 1;
yading@10:     if (coeff_prec == 16) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid coeff precision\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     qlevel = get_sbits(&s->gb, 5);
yading@10:     if (qlevel < 0) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "qlevel %d not supported, maybe buggy stream\n",
yading@10:                qlevel);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     for (i = 0; i < pred_order; i++) {
yading@10:         coeffs[pred_order - i - 1] = get_sbits(&s->gb, coeff_prec);
yading@10:     }
yading@10: 
yading@10:     if ((ret = decode_residuals(s, decoded, pred_order)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     s->dsp.lpc(decoded, coeffs, pred_order, qlevel, s->blocksize);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static inline int decode_subframe(FLACContext *s, int channel)
yading@10: {
yading@10:     int32_t *decoded = s->decoded[channel];
yading@10:     int type, wasted = 0;
yading@10:     int bps = s->bps;
yading@10:     int i, tmp, ret;
yading@10: 
yading@10:     if (channel == 0) {
yading@10:         if (s->ch_mode == FLAC_CHMODE_RIGHT_SIDE)
yading@10:             bps++;
yading@10:     } else {
yading@10:         if (s->ch_mode == FLAC_CHMODE_LEFT_SIDE || s->ch_mode == FLAC_CHMODE_MID_SIDE)
yading@10:             bps++;
yading@10:     }
yading@10: 
yading@10:     if (get_bits1(&s->gb)) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid subframe padding\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     type = get_bits(&s->gb, 6);
yading@10: 
yading@10:     if (get_bits1(&s->gb)) {
yading@10:         int left = get_bits_left(&s->gb);
yading@10:         wasted = 1;
yading@10:         if ( left < 0 ||
yading@10:             (left < bps && !show_bits_long(&s->gb, left)) ||
yading@10:                            !show_bits_long(&s->gb, bps)) {
yading@10:             av_log(s->avctx, AV_LOG_ERROR,
yading@10:                    "Invalid number of wasted bits > available bits (%d) - left=%d\n",
yading@10:                    bps, left);
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         while (!get_bits1(&s->gb))
yading@10:             wasted++;
yading@10:         bps -= wasted;
yading@10:     }
yading@10:     if (bps > 32) {
yading@10:         avpriv_report_missing_feature(s->avctx, "Decorrelated bit depth > 32");
yading@10:         return AVERROR_PATCHWELCOME;
yading@10:     }
yading@10: 
yading@10: //FIXME use av_log2 for types
yading@10:     if (type == 0) {
yading@10:         tmp = get_sbits_long(&s->gb, bps);
yading@10:         for (i = 0; i < s->blocksize; i++)
yading@10:             decoded[i] = tmp;
yading@10:     } else if (type == 1) {
yading@10:         for (i = 0; i < s->blocksize; i++)
yading@10:             decoded[i] = get_sbits_long(&s->gb, bps);
yading@10:     } else if ((type >= 8) && (type <= 12)) {
yading@10:         if ((ret = decode_subframe_fixed(s, decoded, type & ~0x8, bps)) < 0)
yading@10:             return ret;
yading@10:     } else if (type >= 32) {
yading@10:         if ((ret = decode_subframe_lpc(s, decoded, (type & ~0x20)+1, bps)) < 0)
yading@10:             return ret;
yading@10:     } else {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     if (wasted) {
yading@10:         int i;
yading@10:         for (i = 0; i < s->blocksize; i++)
yading@10:             decoded[i] <<= wasted;
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_frame(FLACContext *s)
yading@10: {
yading@10:     int i, ret;
yading@10:     GetBitContext *gb = &s->gb;
yading@10:     FLACFrameInfo fi;
yading@10: 
yading@10:     if (ff_flac_decode_frame_header(s->avctx, gb, &fi, 0)) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid frame header\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     if (s->channels && fi.channels != s->channels && s->got_streaminfo) {
yading@10:         s->channels = s->avctx->channels = fi.channels;
yading@10:         ff_flac_set_channel_layout(s->avctx);
yading@10:         ret = allocate_buffers(s);
yading@10:         if (ret < 0)
yading@10:             return ret;
yading@10:     }
yading@10:     s->channels = s->avctx->channels = fi.channels;
yading@10:     if (!s->avctx->channel_layout)
yading@10:         ff_flac_set_channel_layout(s->avctx);
yading@10:     s->ch_mode = fi.ch_mode;
yading@10: 
yading@10:     if (!s->bps && !fi.bps) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "bps not found in STREAMINFO or frame header\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     if (!fi.bps) {
yading@10:         fi.bps = s->bps;
yading@10:     } else if (s->bps && fi.bps != s->bps) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "switching bps mid-stream is not "
yading@10:                                        "supported\n");
yading@10:         return -1;
yading@10:     }
yading@10: 
yading@10:     if (!s->bps) {
yading@10:         s->bps = s->avctx->bits_per_raw_sample = fi.bps;
yading@10:         flac_set_bps(s);
yading@10:     }
yading@10: 
yading@10:     if (!s->max_blocksize)
yading@10:         s->max_blocksize = FLAC_MAX_BLOCKSIZE;
yading@10:     if (fi.blocksize > s->max_blocksize) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "blocksize %d > %d\n", fi.blocksize,
yading@10:                s->max_blocksize);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     s->blocksize = fi.blocksize;
yading@10: 
yading@10:     if (!s->samplerate && !fi.samplerate) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "sample rate not found in STREAMINFO"
yading@10:                                         " or frame header\n");
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     if (fi.samplerate == 0)
yading@10:         fi.samplerate = s->samplerate;
yading@10:     s->samplerate = s->avctx->sample_rate = fi.samplerate;
yading@10: 
yading@10:     if (!s->got_streaminfo) {
yading@10:         ret = allocate_buffers(s);
yading@10:         if (ret < 0)
yading@10:             return ret;
yading@10:         ff_flacdsp_init(&s->dsp, s->avctx->sample_fmt, s->bps);
yading@10:         s->got_streaminfo = 1;
yading@10:         dump_headers(s->avctx, (FLACStreaminfo *)s);
yading@10:     }
yading@10: 
yading@10: //    dump_headers(s->avctx, (FLACStreaminfo *)s);
yading@10: 
yading@10:     /* subframes */
yading@10:     for (i = 0; i < s->channels; i++) {
yading@10:         if ((ret = decode_subframe(s, i)) < 0)
yading@10:             return ret;
yading@10:     }
yading@10: 
yading@10:     align_get_bits(gb);
yading@10: 
yading@10:     /* frame footer */
yading@10:     skip_bits(gb, 16); /* data crc */
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int flac_decode_frame(AVCodecContext *avctx, void *data,
yading@10:                              int *got_frame_ptr, AVPacket *avpkt)
yading@10: {
yading@10:     AVFrame *frame     = data;
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size = avpkt->size;
yading@10:     FLACContext *s = avctx->priv_data;
yading@10:     int bytes_read = 0;
yading@10:     int ret;
yading@10: 
yading@10:     *got_frame_ptr = 0;
yading@10: 
yading@10:     if (s->max_framesize == 0) {
yading@10:         s->max_framesize =
yading@10:             ff_flac_get_max_frame_size(s->max_blocksize ? s->max_blocksize : FLAC_MAX_BLOCKSIZE,
yading@10:                                        FLAC_MAX_CHANNELS, 32);
yading@10:     }
yading@10: 
yading@10:     if (buf_size > 5 && !memcmp(buf, "\177FLAC", 5)) {
yading@10:         av_log(s->avctx, AV_LOG_DEBUG, "skiping flac header packet 1\n");
yading@10:         return buf_size;
yading@10:     }
yading@10: 
yading@10:     if (buf_size > 0 && (*buf & 0x7F) == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
yading@10:         av_log(s->avctx, AV_LOG_DEBUG, "skiping vorbis comment\n");
yading@10:         return buf_size;
yading@10:     }
yading@10: 
yading@10:     /* check that there is at least the smallest decodable amount of data.
yading@10:        this amount corresponds to the smallest valid FLAC frame possible.
yading@10:        FF F8 69 02 00 00 9A 00 00 34 46 */
yading@10:     if (buf_size < FLAC_MIN_FRAME_SIZE)
yading@10:         return buf_size;
yading@10: 
yading@10:     /* check for inline header */
yading@10:     if (AV_RB32(buf) == MKBETAG('f','L','a','C')) {
yading@10:         if (!s->got_streaminfo && parse_streaminfo(s, buf, buf_size)) {
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "invalid header\n");
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         return get_metadata_size(buf, buf_size);
yading@10:     }
yading@10: 
yading@10:     /* decode frame */
yading@10:     init_get_bits(&s->gb, buf, buf_size*8);
yading@10:     if ((ret = decode_frame(s)) < 0) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "decode_frame() failed\n");
yading@10:         return ret;
yading@10:     }
yading@10:     bytes_read = get_bits_count(&s->gb)/8;
yading@10: 
yading@10:     if ((s->avctx->err_recognition & AV_EF_CRCCHECK) &&
yading@10:         av_crc(av_crc_get_table(AV_CRC_16_ANSI),
yading@10:                0, buf, bytes_read)) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "CRC error at PTS %"PRId64"\n", avpkt->pts);
yading@10:         if (s->avctx->err_recognition & AV_EF_EXPLODE)
yading@10:             return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     /* get output buffer */
yading@10:     frame->nb_samples = s->blocksize;
yading@10:     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     s->dsp.decorrelate[s->ch_mode](frame->data, s->decoded, s->channels,
yading@10:                                    s->blocksize, s->sample_shift);
yading@10: 
yading@10:     if (bytes_read > buf_size) {
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", bytes_read - buf_size);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     if (bytes_read < buf_size) {
yading@10:         av_log(s->avctx, AV_LOG_DEBUG, "underread: %d orig size: %d\n",
yading@10:                buf_size - bytes_read, buf_size);
yading@10:     }
yading@10: 
yading@10:     *got_frame_ptr = 1;
yading@10: 
yading@10:     return bytes_read;
yading@10: }
yading@10: 
yading@10: static av_cold int flac_decode_close(AVCodecContext *avctx)
yading@10: {
yading@10:     FLACContext *s = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&s->decoded_buffer);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_flac_decoder = {
yading@10:     .name           = "flac",
yading@10:     .type           = AVMEDIA_TYPE_AUDIO,
yading@10:     .id             = AV_CODEC_ID_FLAC,
yading@10:     .priv_data_size = sizeof(FLACContext),
yading@10:     .init           = flac_decode_init,
yading@10:     .close          = flac_decode_close,
yading@10:     .decode         = flac_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
yading@10:     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16,
yading@10:                                                       AV_SAMPLE_FMT_S16P,
yading@10:                                                       AV_SAMPLE_FMT_S32,
yading@10:                                                       AV_SAMPLE_FMT_S32P,
yading@10:                                                       AV_SAMPLE_FMT_NONE },
yading@10: };