movenc.c

FFmpeg is an audio/video conversion tool. It includes libavcodec, the leading open source codec libr

/*
 * MOV, 3GP, MP4 encoder.
 * Copyright (c) 2003 Thomas Raivio.
 * Copyright (c) 2004 Gildas Bazin <gbazin at videolan dot org>.
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "avformat.h"
#include "avi.h"
#include "avio.h"

#undef NDEBUG
#include <assert.h>

#define MOV_INDEX_CLUSTER_SIZE 16384
#define globalTimescale 1000

#define MODE_MP4 0
#define MODE_MOV 1
#define MODE_3GP 2

typedef struct MOVIentry {
    unsigned int flags, pos, size;
    unsigned int samplesInChunk;
    char         key_frame;
    unsigned int entries;
} MOVIentry;

typedef struct MOVIndex {
    int         mode;
    int         entry;
    int         mdat_size;
    int         ents_allocated;
    long        timescale;
    long        time;
    long        trackDuration;
    long        sampleCount;
    long        sampleDuration;
    int         hasKeyframes;
    int         trackID;
    AVCodecContext *enc;

    int         vosLen;
    uint8_t     *vosData;
    MOVIentry** cluster;
} MOVTrack;

typedef struct {
    int     mode;
    long    time;
    int     nb_streams;
    int     mdat_written;
    offset_t mdat_pos;
    long    timescale;
    MOVTrack tracks[MAX_STREAMS];
} MOVContext;

static int mov_write_esds_tag(ByteIOContext *pb, MOVTrack* track);

//FIXME supprt 64bit varaint with wide placeholders
static int updateSize (ByteIOContext *pb, int pos)
{
    long curpos = url_ftell(pb);
    url_fseek(pb, pos, SEEK_SET);
    put_be32(pb, curpos - pos); /* rewrite size */
    url_fseek(pb, curpos, SEEK_SET);

    return curpos - pos;
}

/* Chunk offset atom */
static int mov_write_stco_tag(ByteIOContext *pb, MOVTrack* track)
{
    int i;
    int pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "stco");
    put_be32(pb, 0); /* version & flags */
    put_be32(pb, track->entry); /* entry count */
    for (i=0; i<track->entry; i++) {
        int cl = i / MOV_INDEX_CLUSTER_SIZE;
        int id = i % MOV_INDEX_CLUSTER_SIZE;
        put_be32(pb, track->cluster[cl][id].pos);
    }
    return updateSize (pb, pos);
}

/* Sample size atom */
static int mov_write_stsz_tag(ByteIOContext *pb, MOVTrack* track)
{
    int equalChunks = 1;
    int i, j, entries = 0, tst = -1, oldtst = -1;

    int pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "stsz");
    put_be32(pb, 0); /* version & flags */

    for (i=0; i<track->entry; i++) {
        int cl = i / MOV_INDEX_CLUSTER_SIZE;
        int id = i % MOV_INDEX_CLUSTER_SIZE;
        tst = track->cluster[cl][id].size/track->cluster[cl][id].entries;
        if(oldtst != -1 && tst != oldtst) {
            equalChunks = 0;
        }
        oldtst = tst;
        entries += track->cluster[cl][id].entries;
    }
    if (equalChunks) {
        int sSize = track->cluster[0][0].size/track->cluster[0][0].entries;
        put_be32(pb, sSize); // sample size 
        put_be32(pb, entries); // sample count
    }
    else {
        put_be32(pb, 0); // sample size 
        put_be32(pb, entries); // sample count 
        for (i=0; i<track->entry; i++) {
            int cl = i / MOV_INDEX_CLUSTER_SIZE;
            int id = i % MOV_INDEX_CLUSTER_SIZE;
            for ( j=0; j<track->cluster[cl][id].entries; j++) {
                put_be32(pb, track->cluster[cl][id].size /
                         track->cluster[cl][id].entries);
            }
        }
    }
    return updateSize (pb, pos);
}

/* Sample to chunk atom */
static int mov_write_stsc_tag(ByteIOContext *pb, MOVTrack* track)
{
    int index = 0, oldval = -1, i, entryPos, curpos;

    int pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "stsc");
    put_be32(pb, 0); // version & flags 
    entryPos = url_ftell(pb);
    put_be32(pb, track->entry); // entry count 
    for (i=0; i<track->entry; i++) {
        int cl = i / MOV_INDEX_CLUSTER_SIZE;
        int id = i % MOV_INDEX_CLUSTER_SIZE;
        if(oldval != track->cluster[cl][id].samplesInChunk)
        {
            put_be32(pb, i+1); // first chunk 
            put_be32(pb, track->cluster[cl][id].samplesInChunk); // samples per chunk
            put_be32(pb, 0x1); // sample description index 
            oldval = track->cluster[cl][id].samplesInChunk;
            index++;
        }
    }
    curpos = url_ftell(pb);
    url_fseek(pb, entryPos, SEEK_SET);
    put_be32(pb, index); // rewrite size 
    url_fseek(pb, curpos, SEEK_SET);

    return updateSize (pb, pos);
}

/* Sync sample atom */
static int mov_write_stss_tag(ByteIOContext *pb, MOVTrack* track)
{
    long curpos;
    int i, index = 0, entryPos;
    int pos = url_ftell(pb);
    put_be32(pb, 0); // size 
    put_tag(pb, "stss");
    put_be32(pb, 0); // version & flags 
    entryPos = url_ftell(pb);
    put_be32(pb, track->entry); // entry count 
    for (i=0; i<track->entry; i++) {
        int cl = i / MOV_INDEX_CLUSTER_SIZE;
        int id = i % MOV_INDEX_CLUSTER_SIZE;
        if(track->cluster[cl][id].key_frame == 1) {
            put_be32(pb, i+1);
            index++;
        }
    }
    curpos = url_ftell(pb);
    url_fseek(pb, entryPos, SEEK_SET);
    put_be32(pb, index); // rewrite size 
    url_fseek(pb, curpos, SEEK_SET);
    return updateSize (pb, pos);
}

static int mov_write_damr_tag(ByteIOContext *pb)
{
    put_be32(pb, 0x11); /* size */
    put_tag(pb, "damr");
    put_tag(pb, "FFMP");
    put_byte(pb, 0);

    put_be16(pb, 0x80); /* Mode set (all modes for AMR_NB) */
    put_be16(pb, 0xa); /* Mode change period (no restriction) */
    //put_be16(pb, 0x81ff); /* Mode set (all modes for AMR_NB) */
    //put_be16(pb, 1); /* Mode change period (no restriction) */
    return 0x11;
}

static int mov_write_wave_tag(ByteIOContext *pb, MOVTrack* track)
{
    int pos = url_ftell(pb);

    put_be32(pb, 0);     /* size */
    put_tag(pb, "wave");

    put_be32(pb, 12);    /* size */
    put_tag(pb, "frma");
    put_tag(pb, "mp4a");

    put_be32(pb, 12);    /* size */
    put_tag(pb, "mp4a");
    put_be32(pb, 0);

    mov_write_esds_tag(pb, track);

    put_be32(pb, 12);    /* size */
    put_tag(pb, "srcq");
    put_be32(pb, 0x40);

    put_be32(pb, 8);     /* size */
    put_be32(pb, 0);     /* null tag */

    return updateSize (pb, pos);
}

const CodecTag codec_movaudio_tags[] = {
    { CODEC_ID_PCM_MULAW, MKTAG('u', 'l', 'a', 'w') },
    { CODEC_ID_PCM_ALAW, MKTAG('a', 'l', 'a', 'w') },
    { CODEC_ID_ADPCM_IMA_QT, MKTAG('i', 'm', 'a', '4') },
    { CODEC_ID_MACE3, MKTAG('M', 'A', 'C', '3') },
    { CODEC_ID_MACE6, MKTAG('M', 'A', 'C', '6') },
    { CODEC_ID_AAC, MKTAG('m', 'p', '4', 'a') },
    { CODEC_ID_AMR_NB, MKTAG('s', 'a', 'm', 'r') },
    { CODEC_ID_PCM_S16BE, MKTAG('t', 'w', 'o', 's') },
    { CODEC_ID_PCM_S16LE, MKTAG('s', 'o', 'w', 't') },
    { CODEC_ID_MP3, MKTAG('.', 'm', 'p', '3') },
    { 0, 0 },
};

static int mov_write_audio_tag(ByteIOContext *pb, MOVTrack* track)
{
    int pos = url_ftell(pb), tag;
    
    put_be32(pb, 0); /* size */

    tag = codec_get_tag(codec_movaudio_tags, track->enc->codec_id);
    // if no mac fcc found, try with Microsoft tags
    if (!tag)
    {
	int tmp = codec_get_tag(codec_wav_tags, track->enc->codec_id);
	if (tmp)
	    tag = MKTAG('m', 's', ((tmp >> 8) & 0xff), (tmp & 0xff));
    }
    if (!tag)
	put_tag(pb, "    ");
    else
	put_le32(pb, tag); // store it byteswapped

    put_be32(pb, 0); /* Reserved */
    put_be16(pb, 0); /* Reserved */
    put_be16(pb, 1); /* Data-reference index, XXX  == 1 */

    /* SoundDescription */
    if(track->mode == MODE_MOV && track->enc->codec_id == CODEC_ID_AAC)
        put_be16(pb, 1); /* Version 1 */
    else
        put_be16(pb, 0); /* Version 0 */
    put_be16(pb, 0); /* Revision level */
    put_be32(pb, 0); /* Reserved */

    put_be16(pb, track->enc->channels); /* Number of channels */
    /* TODO: Currently hard-coded to 16-bit, there doesn't seem
                 to be a good way to get number of bits of audio */
    put_be16(pb, 0x10); /* Reserved */
    put_be16(pb, 0); /* compression ID (= 0) */
    put_be16(pb, 0); /* packet size (= 0) */
    put_be16(pb, track->timescale); /* Time scale */
    put_be16(pb, 0); /* Reserved */

    if(track->mode == MODE_MOV && track->enc->codec_id == CODEC_ID_AAC)
    {
        /* SoundDescription V1 extended info */
        put_be32(pb, track->enc->frame_size); /* Samples per packet  */
        put_be32(pb, 1536); /* Bytes per packet */
        put_be32(pb, 2); /* Bytes per frame */
        put_be32(pb, 2); /* Bytes per sample */
    }

    if(track->enc->codec_id == CODEC_ID_AAC) {
        if( track->mode == MODE_MOV ) mov_write_wave_tag(pb, track);
        else mov_write_esds_tag(pb, track);
    }
    if(track->enc->codec_id == CODEC_ID_AMR_NB)
        mov_write_damr_tag(pb);
    return updateSize (pb, pos);
}

static int mov_write_d263_tag(ByteIOContext *pb)
{
    put_be32(pb, 0xf); /* size */
    put_tag(pb, "d263");
    put_tag(pb, "FFMP");
    put_be16(pb, 0x0a);
    put_byte(pb, 0);
    return 0xf;
}

/* TODO: No idea about these values */
static int mov_write_svq3_tag(ByteIOContext *pb)
{
    put_be32(pb, 0x15);
    put_tag(pb, "SMI ");
    put_tag(pb, "SEQH");
    put_be32(pb, 0x5);
    put_be32(pb, 0xe2c0211d);
    put_be32(pb, 0xc0000000);
    put_byte(pb, 0);   
    return 0x15;
}

static unsigned int descrLength(unsigned int len)
{
    if (len < 0x00000080)
        return 2 + len;
    else if (len < 0x00004000)
        return 3 + len;
    else if(len < 0x00200000)
        return 4 + len;
    else
        return 5 + len;
}

static void putDescr(ByteIOContext *pb, int tag, int size)
{
    uint32_t len;
    uint8_t  vals[4];

    len = size;
    vals[3] = (uint8_t)(len & 0x7f);
    len >>= 7;
    vals[2] = (uint8_t)((len & 0x7f) | 0x80); 
    len >>= 7;
    vals[1] = (uint8_t)((len & 0x7f) | 0x80); 
    len >>= 7;
    vals[0] = (uint8_t)((len & 0x7f) | 0x80);

    put_byte(pb, tag); // DescriptorTag

    if (size < 0x00000080)
    {
        put_byte(pb, vals[3]);
    }
    else if (size < 0x00004000)
    {
        put_byte(pb, vals[2]);
        put_byte(pb, vals[3]);
    }
    else if (size < 0x00200000)
    {
        put_byte(pb, vals[1]);
        put_byte(pb, vals[2]);