PeerStreamer

/*

 * AIFF/AIFF-C muxer

 * Copyright (c) 2006  Patrick Guimond

 *

 * 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 "aiff.h"

#include "avio_internal.h"

typedef struct {

    int64_t form;

    int64_t frames;

    int64_t ssnd;

} AIFFOutputContext;

static int aiff_write_header(AVFormatContext *s)

{

    AIFFOutputContext *aiff = s->priv_data;

    AVIOContext *pb = s->pb;

    AVCodecContext *enc = s->streams[0]->codec;

    AVExtFloat sample_rate;

    int aifc = 0;

    /* First verify if format is ok */

    if (!enc->codec_tag)

        return -1;

    if (enc->codec_tag != MKTAG('N','O','N','E'))

        aifc = 1;

    /* FORM AIFF header */

    ffio_wfourcc(pb, "FORM");

    aiff->form = url_ftell(pb);

    avio_wb32(pb, 0);                    /* file length */

    ffio_wfourcc(pb, aifc ? "AIFC" : "AIFF");

    if (aifc) { // compressed audio

        enc->bits_per_coded_sample = 16;

        if (!enc->block_align) {

            av_log(s, AV_LOG_ERROR, "block align not set\n");

            return -1;

        }

        /* Version chunk */

        ffio_wfourcc(pb, "FVER");

        avio_wb32(pb, 4);

        avio_wb32(pb, 0xA2805140);

    }

    /* Common chunk */

    ffio_wfourcc(pb, "COMM");

    avio_wb32(pb, aifc ? 24 : 18); /* size */

    avio_wb16(pb, enc->channels);  /* Number of channels */

    aiff->frames = url_ftell(pb);

    avio_wb32(pb, 0);              /* Number of frames */

    if (!enc->bits_per_coded_sample)

        enc->bits_per_coded_sample = av_get_bits_per_sample(enc->codec_id);

    if (!enc->bits_per_coded_sample) {

        av_log(s, AV_LOG_ERROR, "could not compute bits per sample\n");

        return -1;

    }

    if (!enc->block_align)

        enc->block_align = (enc->bits_per_coded_sample * enc->channels) >> 3;

    avio_wb16(pb, enc->bits_per_coded_sample); /* Sample size */

    sample_rate = av_dbl2ext((double)enc->sample_rate);

    avio_write(pb, (uint8_t*)&sample_rate, sizeof(sample_rate));

    if (aifc) {

        avio_wl32(pb, enc->codec_tag);

        avio_wb16(pb, 0);

    }

    /* Sound data chunk */

    ffio_wfourcc(pb, "SSND");

    aiff->ssnd = url_ftell(pb);         /* Sound chunk size */

    avio_wb32(pb, 0);                    /* Sound samples data size */

    avio_wb32(pb, 0);                    /* Data offset */

    avio_wb32(pb, 0);                    /* Block-size (block align) */

    av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);

    /* Data is starting here */

    put_flush_packet(pb);

    return 0;

}

static int aiff_write_packet(AVFormatContext *s, AVPacket *pkt)

{

    AVIOContext *pb = s->pb;

    avio_write(pb, pkt->data, pkt->size);

    return 0;

}

static int aiff_write_trailer(AVFormatContext *s)

{

    AVIOContext *pb = s->pb;

    AIFFOutputContext *aiff = s->priv_data;

    AVCodecContext *enc = s->streams[0]->codec;

    /* Chunks sizes must be even */

    int64_t file_size, end_size;

    end_size = file_size = url_ftell(pb);

    if (file_size & 1) {

        avio_w8(pb, 0);

        end_size++;

    }

    if (!url_is_streamed(s->pb)) {

        /* File length */

        url_fseek(pb, aiff->form, SEEK_SET);

        avio_wb32(pb, file_size - aiff->form - 4);

        /* Number of sample frames */

        url_fseek(pb, aiff->frames, SEEK_SET);

        avio_wb32(pb, (file_size-aiff->ssnd-12)/enc->block_align);

        /* Sound Data chunk size */

        url_fseek(pb, aiff->ssnd, SEEK_SET);

        avio_wb32(pb, file_size - aiff->ssnd - 4);

        /* return to the end */

        url_fseek(pb, end_size, SEEK_SET);

        put_flush_packet(pb);

    }

    return 0;

}

AVOutputFormat ff_aiff_muxer = {

    "aiff",

    NULL_IF_CONFIG_SMALL("Audio IFF"),

    "audio/aiff",

    "aif,aiff,afc,aifc",

    sizeof(AIFFOutputContext),

    CODEC_ID_PCM_S16BE,

    CODEC_ID_NONE,

    aiff_write_header,

    aiff_write_packet,

    aiff_write_trailer,

    .codec_tag= (const AVCodecTag* const []){ff_codec_aiff_tags, 0},

};