PeerStreamer

/*

 * RIFF codec tags

 * Copyright (c) 2000 Fabrice Bellard.

 *

 * 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 "avformat.h"

#include "avcodec.h"

#include "riff.h"

#include "allformats.h" // for asf_muxer

/* Note: when encoding, the first matching tag is used, so order is

   important if multiple tags possible for a given codec. */

const AVCodecTag codec_bmp_tags[] = {

    { CODEC_ID_H264, MKTAG('H', '2', '6', '4') },

    { CODEC_ID_H264, MKTAG('h', '2', '6', '4') },

    { CODEC_ID_H264, MKTAG('X', '2', '6', '4') },

    { CODEC_ID_H264, MKTAG('x', '2', '6', '4') },

    { CODEC_ID_H264, MKTAG('a', 'v', 'c', '1') },

    { CODEC_ID_H264, MKTAG('V', 'S', 'S', 'H') },

    { CODEC_ID_H263, MKTAG('H', '2', '6', '3') },

    { CODEC_ID_H263P, MKTAG('H', '2', '6', '3') },

    { CODEC_ID_H263I, MKTAG('I', '2', '6', '3') }, /* intel h263 */

    { CODEC_ID_H261, MKTAG('H', '2', '6', '1') },

    /* added based on MPlayer */

    { CODEC_ID_H263P, MKTAG('U', '2', '6', '3') },

    { CODEC_ID_H263P, MKTAG('v', 'i', 'v', '1') },

    { CODEC_ID_MPEG4, MKTAG('F', 'M', 'P', '4') },

    { CODEC_ID_MPEG4, MKTAG('D', 'I', 'V', 'X') },

    { CODEC_ID_MPEG4, MKTAG('D', 'X', '5', '0') },

    { CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') },

    { CODEC_ID_MPEG4, MKTAG('M', 'P', '4', 'S') },

    { CODEC_ID_MPEG4, MKTAG('M', '4', 'S', '2') },

    { CODEC_ID_MPEG4, MKTAG(0x04, 0, 0, 0) }, /* some broken avi use this */

    /* added based on MPlayer */

    { CODEC_ID_MPEG4, MKTAG('D', 'I', 'V', '1') },

    { CODEC_ID_MPEG4, MKTAG('B', 'L', 'Z', '0') },

    { CODEC_ID_MPEG4, MKTAG('m', 'p', '4', 'v') },

    { CODEC_ID_MPEG4, MKTAG('U', 'M', 'P', '4') },

    { CODEC_ID_MPEG4, MKTAG('W', 'V', '1', 'F') },

    { CODEC_ID_MPEG4, MKTAG('S', 'E', 'D', 'G') },

    { CODEC_ID_MPEG4, MKTAG('R', 'M', 'P', '4') },

    { CODEC_ID_MSMPEG4V3, MKTAG('D', 'I', 'V', '3') }, /* default signature when using MSMPEG4 */

    { CODEC_ID_MSMPEG4V3, MKTAG('M', 'P', '4', '3') },

    /* added based on MPlayer */

    { CODEC_ID_MSMPEG4V3, MKTAG('M', 'P', 'G', '3') },

    { CODEC_ID_MSMPEG4V3, MKTAG('D', 'I', 'V', '5') },

    { CODEC_ID_MSMPEG4V3, MKTAG('D', 'I', 'V', '6') },

    { CODEC_ID_MSMPEG4V3, MKTAG('D', 'I', 'V', '4') },

    { CODEC_ID_MSMPEG4V3, MKTAG('A', 'P', '4', '1') },

    { CODEC_ID_MSMPEG4V3, MKTAG('C', 'O', 'L', '1') },

    { CODEC_ID_MSMPEG4V3, MKTAG('C', 'O', 'L', '0') },

    { CODEC_ID_MSMPEG4V2, MKTAG('M', 'P', '4', '2') },

    /* added based on MPlayer */

    { CODEC_ID_MSMPEG4V2, MKTAG('D', 'I', 'V', '2') },

    { CODEC_ID_MSMPEG4V1, MKTAG('M', 'P', 'G', '4') },

    { CODEC_ID_WMV1, MKTAG('W', 'M', 'V', '1') },

    /* added based on MPlayer */

    { CODEC_ID_WMV2, MKTAG('W', 'M', 'V', '2') },

    { CODEC_ID_DVVIDEO, MKTAG('d', 'v', 's', 'd') },

    { CODEC_ID_DVVIDEO, MKTAG('d', 'v', 'h', 'd') },

    { CODEC_ID_DVVIDEO, MKTAG('d', 'v', 's', 'l') },

    { CODEC_ID_DVVIDEO, MKTAG('d', 'v', '2', '5') },

    { CODEC_ID_MPEG1VIDEO, MKTAG('m', 'p', 'g', '1') },

    { CODEC_ID_MPEG1VIDEO, MKTAG('m', 'p', 'g', '2') },

    { CODEC_ID_MPEG2VIDEO, MKTAG('m', 'p', 'g', '2') },

    { CODEC_ID_MPEG2VIDEO, MKTAG('M', 'P', 'E', 'G') },

    { CODEC_ID_MPEG1VIDEO, MKTAG('P', 'I', 'M', '1') },

    { CODEC_ID_MPEG1VIDEO, MKTAG('V', 'C', 'R', '2') },

    { CODEC_ID_MPEG1VIDEO, 0x10000001 },

    { CODEC_ID_MPEG2VIDEO, 0x10000002 },

    { CODEC_ID_MPEG2VIDEO, MKTAG('D', 'V', 'R', ' ') },

    { CODEC_ID_MJPEG, MKTAG('M', 'J', 'P', 'G') },

    { CODEC_ID_MJPEG, MKTAG('L', 'J', 'P', 'G') },

    { CODEC_ID_LJPEG, MKTAG('L', 'J', 'P', 'G') },

    { CODEC_ID_MJPEG, MKTAG('J', 'P', 'G', 'L') }, /* Pegasus lossless JPEG */

    { CODEC_ID_MJPEG, MKTAG('M', 'J', 'L', 'S') }, /* JPEG-LS custom FOURCC for avi - decoder */

    { CODEC_ID_MJPEG, MKTAG('j', 'p', 'e', 'g') },

    { CODEC_ID_MJPEG, MKTAG('I', 'J', 'P', 'G') },

    { CODEC_ID_JPEGLS, MKTAG('M', 'J', 'L', 'S') }, /* JPEG-LS custom FOURCC for avi - encoder */

    { CODEC_ID_HUFFYUV, MKTAG('H', 'F', 'Y', 'U') },

    { CODEC_ID_FFVHUFF, MKTAG('F', 'F', 'V', 'H') },

    { CODEC_ID_CYUV, MKTAG('C', 'Y', 'U', 'V') },

    { CODEC_ID_RAWVIDEO, 0 },

    { CODEC_ID_RAWVIDEO, MKTAG('I', '4', '2', '0') },

    { CODEC_ID_RAWVIDEO, MKTAG('Y', 'U', 'Y', '2') },

    { CODEC_ID_RAWVIDEO, MKTAG('Y', '4', '2', '2') },

    { CODEC_ID_RAWVIDEO, MKTAG('Y', 'V', '1', '2') },

    { CODEC_ID_RAWVIDEO, MKTAG('U', 'Y', 'V', 'Y') },

    { CODEC_ID_RAWVIDEO, MKTAG('I', 'Y', 'U', 'V') },

    { CODEC_ID_RAWVIDEO, MKTAG('Y', '8', '0', '0') },

    { CODEC_ID_INDEO3, MKTAG('I', 'V', '3', '1') },

    { CODEC_ID_INDEO3, MKTAG('I', 'V', '3', '2') },

    { CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },

    { CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },

    { CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },

    { CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },

    { CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },

    { CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },

    { CODEC_ID_ASV1, MKTAG('A', 'S', 'V', '1') },

    { CODEC_ID_ASV2, MKTAG('A', 'S', 'V', '2') },

    { CODEC_ID_VCR1, MKTAG('V', 'C', 'R', '1') },

    { CODEC_ID_FFV1, MKTAG('F', 'F', 'V', '1') },

    { CODEC_ID_XAN_WC4, MKTAG('X', 'x', 'a', 'n') },

    { CODEC_ID_MSRLE, MKTAG('m', 'r', 'l', 'e') },

    { CODEC_ID_MSRLE, MKTAG(0x1, 0x0, 0x0, 0x0) },

    { CODEC_ID_MSVIDEO1, MKTAG('M', 'S', 'V', 'C') },

    { CODEC_ID_MSVIDEO1, MKTAG('m', 's', 'v', 'c') },

    { CODEC_ID_MSVIDEO1, MKTAG('C', 'R', 'A', 'M') },

    { CODEC_ID_MSVIDEO1, MKTAG('c', 'r', 'a', 'm') },

    { CODEC_ID_MSVIDEO1, MKTAG('W', 'H', 'A', 'M') },

    { CODEC_ID_MSVIDEO1, MKTAG('w', 'h', 'a', 'm') },

    { CODEC_ID_CINEPAK, MKTAG('c', 'v', 'i', 'd') },

    { CODEC_ID_TRUEMOTION1, MKTAG('D', 'U', 'C', 'K') },

    { CODEC_ID_MSZH, MKTAG('M', 'S', 'Z', 'H') },

    { CODEC_ID_ZLIB, MKTAG('Z', 'L', 'I', 'B') },

    { CODEC_ID_SNOW, MKTAG('S', 'N', 'O', 'W') },

    { CODEC_ID_4XM, MKTAG('4', 'X', 'M', 'V') },

    { CODEC_ID_FLV1, MKTAG('F', 'L', 'V', '1') },

    { CODEC_ID_FLASHSV, MKTAG('F', 'S', 'V', '1') },

    { CODEC_ID_VP6F, MKTAG('V', 'P', '6', 'F') },

    { CODEC_ID_SVQ1, MKTAG('s', 'v', 'q', '1') },

    { CODEC_ID_TSCC, MKTAG('t', 's', 'c', 'c') },

    { CODEC_ID_ULTI, MKTAG('U', 'L', 'T', 'I') },

    { CODEC_ID_VIXL, MKTAG('V', 'I', 'X', 'L') },

    { CODEC_ID_QPEG, MKTAG('Q', 'P', 'E', 'G') },

    { CODEC_ID_QPEG, MKTAG('Q', '1', '.', '0') },

    { CODEC_ID_QPEG, MKTAG('Q', '1', '.', '1') },

    { CODEC_ID_WMV3, MKTAG('W', 'M', 'V', '3') },

    { CODEC_ID_VC1, MKTAG('W', 'V', 'C', '1') },

    { CODEC_ID_LOCO, MKTAG('L', 'O', 'C', 'O') },

    { CODEC_ID_WNV1, MKTAG('W', 'N', 'V', '1') },

    { CODEC_ID_AASC, MKTAG('A', 'A', 'S', 'C') },

    { CODEC_ID_INDEO2, MKTAG('R', 'T', '2', '1') },

    { CODEC_ID_FRAPS, MKTAG('F', 'P', 'S', '1') },

    { CODEC_ID_THEORA, MKTAG('t', 'h', 'e', 'o') },

    { CODEC_ID_TRUEMOTION2, MKTAG('T', 'M', '2', '0') },

    { CODEC_ID_CSCD, MKTAG('C', 'S', 'C', 'D') },

    { CODEC_ID_ZMBV, MKTAG('Z', 'M', 'B', 'V') },

    { CODEC_ID_KMVC, MKTAG('K', 'M', 'V', 'C') },

    { CODEC_ID_CAVS, MKTAG('C', 'A', 'V', 'S') },

    { CODEC_ID_JPEG2000, MKTAG('M', 'J', '2', 'C') },

    { CODEC_ID_VMNC, MKTAG('V', 'M', 'n', 'c') },

    { CODEC_ID_TARGA, MKTAG('t', 'g', 'a', ' ') },

    { CODEC_ID_NONE, 0 },

};

const AVCodecTag codec_wav_tags[] = {

    { CODEC_ID_MP2, 0x50 },

    { CODEC_ID_MP3, 0x55 },

    { CODEC_ID_AC3, 0x2000 },

    { CODEC_ID_DTS, 0x2001 },

    { CODEC_ID_PCM_S16LE, 0x01 },

    { CODEC_ID_PCM_U8, 0x01 }, /* must come after s16le in this list */

    { CODEC_ID_PCM_S24LE, 0x01 },

    { CODEC_ID_PCM_S32LE, 0x01 },

    { CODEC_ID_PCM_ALAW, 0x06 },

    { CODEC_ID_PCM_MULAW, 0x07 },

    { CODEC_ID_ADPCM_MS, 0x02 },

    { CODEC_ID_ADPCM_IMA_WAV, 0x11 },

    { CODEC_ID_ADPCM_YAMAHA, 0x20 },

    { CODEC_ID_ADPCM_G726, 0x45 },

    { CODEC_ID_ADPCM_IMA_DK4, 0x61 },  /* rogue format number */

    { CODEC_ID_ADPCM_IMA_DK3, 0x62 },  /* rogue format number */

    { CODEC_ID_WMAV1, 0x160 },

    { CODEC_ID_WMAV2, 0x161 },

    { CODEC_ID_AAC, 0x706d },

    { CODEC_ID_AAC, 0xff },

    { CODEC_ID_VORBIS, ('V'<<8)+'o' }, //HACK/FIXME, does vorbis in WAV/AVI have an (in)official id?

    { CODEC_ID_SONIC, 0x2048 },

    { CODEC_ID_SONIC_LS, 0x2048 },

    { CODEC_ID_ADPCM_CT, 0x200 },

    { CODEC_ID_ADPCM_SWF, ('S'<<8)+'F' },

    { CODEC_ID_TRUESPEECH, 0x22 },

    { CODEC_ID_FLAC, 0xF1AC },

    { CODEC_ID_IMC, 0x401 },

    { CODEC_ID_GSM_MS, 0x31 },

    /* FIXME: All of the IDs below are not 16 bit and thus illegal. */

    // for NuppelVideo (nuv.c)

    { CODEC_ID_PCM_S16LE, MKTAG('R', 'A', 'W', 'A') },

    { CODEC_ID_MP3, MKTAG('L', 'A', 'M', 'E') },

    { CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },

    { 0, 0 },

};

unsigned int codec_get_tag(const AVCodecTag *tags, int id)

{

    while (tags->id != CODEC_ID_NONE) {

        if (tags->id == id)

            return tags->tag;

        tags++;

    }

    return 0;

}

enum CodecID codec_get_id(const AVCodecTag *tags, unsigned int tag)

{

    while (tags->id != CODEC_ID_NONE) {

        if(   toupper((tag >> 0)&0xFF) == toupper((tags->tag >> 0)&0xFF)

           && toupper((tag >> 8)&0xFF) == toupper((tags->tag >> 8)&0xFF)

           && toupper((tag >>16)&0xFF) == toupper((tags->tag >>16)&0xFF)

           && toupper((tag >>24)&0xFF) == toupper((tags->tag >>24)&0xFF))

            return tags->id;

        tags++;

    }

    return CODEC_ID_NONE;

}

unsigned int av_codec_get_tag(const AVCodecTag *tags[4], enum CodecID id)

{

    int i;

    for(i=0; tags && tags[i]; i++){

        int tag= codec_get_tag(tags[i], id);

        if(tag) return tag;

    }

    return 0;

}

enum CodecID av_codec_get_id(const AVCodecTag *tags[4], unsigned int tag)

{

    int i;

    for(i=0; tags && tags[i]; i++){

        enum CodecID id= codec_get_id(tags[i], tag);

        if(id!=CODEC_ID_NONE) return id;

    }

    return CODEC_ID_NONE;

}

unsigned int codec_get_bmp_tag(int id)

{

    return codec_get_tag(codec_bmp_tags, id);

}

unsigned int codec_get_wav_tag(int id)

{

    return codec_get_tag(codec_wav_tags, id);

}

enum CodecID codec_get_bmp_id(unsigned int tag)

{

    return codec_get_id(codec_bmp_tags, tag);

}

enum CodecID codec_get_wav_id(unsigned int tag)

{

    return codec_get_id(codec_wav_tags, tag);

}

#ifdef CONFIG_MUXERS

offset_t start_tag(ByteIOContext *pb, const char *tag)

{

    put_tag(pb, tag);

    put_le32(pb, 0);

    return url_ftell(pb);

}

void end_tag(ByteIOContext *pb, offset_t start)

{

    offset_t pos;

    pos = url_ftell(pb);

    url_fseek(pb, start - 4, SEEK_SET);

    put_le32(pb, (uint32_t)(pos - start));

    url_fseek(pb, pos, SEEK_SET);

}

/* WAVEFORMATEX header */

/* returns the size or -1 on error */

int put_wav_header(ByteIOContext *pb, AVCodecContext *enc)

{

    int bps, blkalign, bytespersec;

    int hdrsize = 18;

    if(!enc->codec_tag || enc->codec_tag > 0xffff)

        return -1;

    put_le16(pb, enc->codec_tag);

    put_le16(pb, enc->channels);

    put_le32(pb, enc->sample_rate);

    if (enc->codec_id == CODEC_ID_PCM_U8 ||

        enc->codec_id == CODEC_ID_PCM_ALAW ||

        enc->codec_id == CODEC_ID_PCM_MULAW) {

        bps = 8;

    } else if (enc->codec_id == CODEC_ID_MP2 || enc->codec_id == CODEC_ID_MP3 || enc->codec_id == CODEC_ID_GSM_MS) {

        bps = 0;

    } else if (enc->codec_id == CODEC_ID_ADPCM_IMA_WAV || enc->codec_id == CODEC_ID_ADPCM_MS || enc->codec_id == CODEC_ID_ADPCM_G726 || enc->codec_id == CODEC_ID_ADPCM_YAMAHA) { //

        bps = 4;

    } else if (enc->codec_id == CODEC_ID_PCM_S24LE) {

        bps = 24;

    } else if (enc->codec_id == CODEC_ID_PCM_S32LE) {

        bps = 32;

    } else {

        bps = 16;

    }

    if(bps != enc->bits_per_sample && enc->bits_per_sample){

        av_log(enc, AV_LOG_WARNING, "requested bits_per_sample (%d) and actually stored (%d) differ\n", enc->bits_per_sample, bps);

    }

    if (enc->codec_id == CODEC_ID_MP2 || enc->codec_id == CODEC_ID_MP3 || enc->codec_id == CODEC_ID_GSM_MS) {

        blkalign = enc->frame_size; //this is wrong, but seems many demuxers dont work if this is set correctly

        //blkalign = 144 * enc->bit_rate/enc->sample_rate;

    } else if (enc->codec_id == CODEC_ID_ADPCM_G726) { //

        blkalign = 1;

    } else if (enc->block_align != 0) { /* specified by the codec */

        blkalign = enc->block_align;

    } else

        blkalign = enc->channels*bps >> 3;

    if (enc->codec_id == CODEC_ID_PCM_U8 ||

        enc->codec_id == CODEC_ID_PCM_S24LE ||

        enc->codec_id == CODEC_ID_PCM_S32LE ||

        enc->codec_id == CODEC_ID_PCM_S16LE) {

        bytespersec = enc->sample_rate * blkalign;

    } else {

        bytespersec = enc->bit_rate / 8;

    }

    put_le32(pb, bytespersec); /* bytes per second */

    put_le16(pb, blkalign); /* block align */

    put_le16(pb, bps); /* bits per sample */

    if (enc->codec_id == CODEC_ID_MP3) {

        put_le16(pb, 12); /* wav_extra_size */

        hdrsize += 12;

        put_le16(pb, 1); /* wID */

        put_le32(pb, 2); /* fdwFlags */

        put_le16(pb, 1152); /* nBlockSize */

        put_le16(pb, 1); /* nFramesPerBlock */

        put_le16(pb, 1393); /* nCodecDelay */

    } else if (enc->codec_id == CODEC_ID_MP2) {

        put_le16(pb, 22); /* wav_extra_size */

        hdrsize += 22;

        put_le16(pb, 2);  /* fwHeadLayer */

        put_le32(pb, enc->bit_rate); /* dwHeadBitrate */

        put_le16(pb, enc->channels == 2 ? 1 : 8); /* fwHeadMode */

        put_le16(pb, 0);  /* fwHeadModeExt */

        put_le16(pb, 1);  /* wHeadEmphasis */

        put_le16(pb, 16); /* fwHeadFlags */

        put_le32(pb, 0);  /* dwPTSLow */

        put_le32(pb, 0);  /* dwPTSHigh */

    } else if (enc->codec_id == CODEC_ID_GSM_MS) {

        put_le16(pb, 2); /* wav_extra_size */

        hdrsize += 2;

        put_le16(pb, enc->frame_size); /* wSamplesPerBlock */

    } else if (enc->codec_id == CODEC_ID_ADPCM_IMA_WAV) {

        put_le16(pb, 2); /* wav_extra_size */

        hdrsize += 2;

        put_le16(pb, enc->frame_size); /* wSamplesPerBlock */

    } else if(enc->extradata_size){

        put_le16(pb, enc->extradata_size);

        put_buffer(pb, enc->extradata, enc->extradata_size);

        hdrsize += enc->extradata_size;

        if(hdrsize&1){

            hdrsize++;

            put_byte(pb, 0);

        }

    } else {

        hdrsize -= 2;

    }

    return hdrsize;

}

/* BITMAPINFOHEADER header */

void put_bmp_header(ByteIOContext *pb, AVCodecContext *enc, const AVCodecTag *tags, int for_asf)

{

    put_le32(pb, 40 + enc->extradata_size); /* size */

    put_le32(pb, enc->width);

    put_le32(pb, enc->height);

    put_le16(pb, 1); /* planes */

    put_le16(pb, enc->bits_per_sample ? enc->bits_per_sample : 24); /* depth */

    /* compression type */

    put_le32(pb, enc->codec_tag);

    put_le32(pb, enc->width * enc->height * 3);

    put_le32(pb, 0);

    put_le32(pb, 0);

    put_le32(pb, 0);

    put_le32(pb, 0);

    put_buffer(pb, enc->extradata, enc->extradata_size);

    if (enc->extradata_size & 1)

        put_byte(pb, 0);

}

#endif //CONFIG_MUXERS

#ifdef CONFIG_DEMUXERS

/* We could be given one of the three possible structures here:

 * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure

 * is an expansion of the previous one with the fields added

 * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and

 * WAVEFORMATEX adds 'WORD  cbSize' and basically makes itself

 * an openended structure.

 */

void get_wav_header(ByteIOContext *pb, AVCodecContext *codec, int size)

{

    int id;

    id = get_le16(pb);

    codec->codec_type = CODEC_TYPE_AUDIO;

    codec->codec_tag = id;

    codec->channels = get_le16(pb);

    codec->sample_rate = get_le32(pb);

    codec->bit_rate = get_le32(pb) * 8;

    codec->block_align = get_le16(pb);

    if (size == 14) {  /* We're dealing with plain vanilla WAVEFORMAT */

        codec->bits_per_sample = 8;

    }else

        codec->bits_per_sample = get_le16(pb);

    if (size >= 18) {  /* We're obviously dealing with WAVEFORMATEX */

        int cbSize = get_le16(pb); /* cbSize */

        size -= 18;

        cbSize = FFMIN(size, cbSize);

        if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */

            codec->bits_per_sample = get_le16(pb);

            get_le32(pb); /* dwChannelMask */

            id = get_le32(pb); /* 4 first bytes of GUID */

            url_fskip(pb, 12); /* skip end of GUID */

            cbSize -= 22;

            size -= 22;

        }

        codec->extradata_size = cbSize;

        if (cbSize > 0) {

            codec->extradata = av_mallocz(codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

            get_buffer(pb, codec->extradata, codec->extradata_size);

            size -= cbSize;

        }

        /* It is possible for the chunk to contain garbage at the end */

        if (size > 0)

            url_fskip(pb, size);

    }

    codec->codec_id = wav_codec_get_id(id, codec->bits_per_sample);

}

int wav_codec_get_id(unsigned int tag, int bps)

{

    int id;

    id = codec_get_id(codec_wav_tags, tag);

    if (id <= 0)

        return id;

    /* handle specific u8 codec */

    if (id == CODEC_ID_PCM_S16LE && bps == 8)

        id = CODEC_ID_PCM_U8;

    if (id == CODEC_ID_PCM_S16LE && bps == 24)

        id = CODEC_ID_PCM_S24LE;

    if (id == CODEC_ID_PCM_S16LE && bps == 32)

        id = CODEC_ID_PCM_S32LE;

    return id;

}

#endif // CONFIG_DEMUXERS

void ff_parse_specific_params(AVCodecContext *stream, int *au_rate, int *au_ssize, int *au_scale)

{

    int gcd;

    *au_ssize= stream->block_align;

    if(stream->frame_size && stream->sample_rate){

        *au_scale=stream->frame_size;

        *au_rate= stream->sample_rate;

    }else if(stream->codec_type == CODEC_TYPE_VIDEO){

        *au_scale= stream->time_base.num;

        *au_rate = stream->time_base.den;

    }else{

        *au_scale= stream->block_align ? stream->block_align*8 : 8;

        *au_rate = stream->bit_rate;

    }

    gcd= ff_gcd(*au_scale, *au_rate);

    *au_scale /= gcd;

    *au_rate /= gcd;

}