movenc.c

现在关于h.264的源码很多

/*
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */
#include "avformat.h"
#include "avi.h"
#include "avio.h"
#include "mov.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
#define MODE_PSP 3 // example working PSP command line:
// ffmpeg -i testinput.avi  -f psp -r 14.985 -s 320x240 -b 768 -ar 24000 -ab 32 M4V00001.MP4
#define MODE_3G2 4

typedef struct MOVIentry {
    unsigned int flags, size;
    uint64_t     pos;
    unsigned int samplesInChunk;
    char         key_frame;
    unsigned int entries;
    int64_t      cts;
} MOVIentry;

typedef struct MOVIndex {
    int         mode;
    int         entry;
    uint64_t    mdat_size;
    int         ents_allocated;
    long        timescale;
    long        time;
    int64_t     trackDuration;
    long        sampleCount;
    long        sampleDuration;
    int         hasKeyframes;
    int         hasBframes;
    int         language;
    int         trackID;
    AVCodecContext *enc;

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

typedef struct MOVContext {
    int     mode;
    int64_t 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);

/* output language code from iso639 language name */
extern int ff_mov_iso639_to_lang(const char *lang, int mp4);

//FIXME supprt 64bit varaint with wide placeholders
static offset_t updateSize (ByteIOContext *pb, offset_t pos)
{
    offset_t 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 mode64 = 0; //   use 32 bit size variant if possible
    offset_t pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    if (pos > UINT32_MAX) {
        mode64 = 1;
        put_tag(pb, "co64");
    } else
        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;
        if(mode64 == 1)
            put_be64(pb, track->cluster[cl][id].pos);
        else
            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;

    offset_t 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;
    offset_t entryPos, curpos;

    offset_t 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)
{
    offset_t curpos, entryPos;
    int i, index = 0;
    offset_t 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)
{
    offset_t 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);
}

static 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_AMR_WB, MKTAG('s', 'a', 'w', 'b') },
    { 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') },
    { CODEC_ID_NONE, 0 },
};

static int mov_write_audio_tag(ByteIOContext *pb, MOVTrack* track)
{
    offset_t pos = url_ftell(pb);
    int tag;

    put_be32(pb, 0); /* size */

    tag = track->enc->codec_tag;
    if (!tag)
    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);
        tag = MKTAG('m', 's', ((tmp >> 8) & 0xff), (tmp & 0xff));
    }
    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 */

    if(track->enc->codec_id == CODEC_ID_AAC ||
       track->enc->codec_id == CODEC_ID_MP3)
    {
        put_be16(pb, 0xfffe); /* compression ID (vbr)*/
    }
    else
    {
        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 uint8_t *avc_find_startcode( uint8_t *p, uint8_t *end )
{
    uint8_t *a = p + 4 - ((int)p & 3);

    for( end -= 3; p < a && p < end; p++ ) {
        if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
            return p;
    }

    for( end -= 3; p < end; p += 4 ) {
        uint32_t x = *(uint32_t*)p;
//      if( (x - 0x01000100) & (~x) & 0x80008000 ) // little endian
//      if( (x - 0x00010001) & (~x) & 0x00800080 ) // big endian
        if( (x - 0x01010101) & (~x) & 0x80808080 ) { // generic
            if( p[1] == 0 ) {
                if( p[0] == 0 && p[2] == 1 )
                    return p;
                if( p[2] == 0 && p[3] == 1 )
                    return p+1;
            }
            if( p[3] == 0 ) {
                if( p[2] == 0 && p[4] == 1 )
                    return p+2;
                if( p[4] == 0 && p[5] == 1 )
                    return p+3;
            }
        }
    }

    for( end += 3; p < end; p++ ) {
        if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
            return p;
    }

    return end + 3;
}

static void avc_parse_nal_units(uint8_t **buf, int *size)
{
    ByteIOContext pb;
    uint8_t *p = *buf;
    uint8_t *end = p + *size;
    uint8_t *nal_start, *nal_end;

    url_open_dyn_buf(&pb);
    nal_start = avc_find_startcode(p, end);
    while (nal_start < end) {
        while(!*(nal_start++));
        nal_end = avc_find_startcode(nal_start, end);
        put_be32(&pb, nal_end - nal_start);
        put_buffer(&pb, nal_start, nal_end - nal_start);
        nal_start = nal_end;
    }
    av_freep(buf);
    *size = url_close_dyn_buf(&pb, buf);
}

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

    put_be32(pb, 0);
    put_tag(pb, "avcC");
    if (track->vosLen > 6) {
        /* check for h264 start code */
        if (BE_32(track->vosData) == 0x00000001) {
            uint8_t *buf, *end;
            uint32_t sps_size=0, pps_size=0;
            uint8_t *sps=0, *pps=0;

            avc_parse_nal_units(&track->vosData, &track->vosLen);
            buf = track->vosData;
            end = track->vosData + track->vosLen;

            put_byte(pb, 1); /* version */
            put_byte(pb, 77); /* profile */
            put_byte(pb, 64); /* profile compat */
            put_byte(pb, 30); /* level */
            put_byte(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */
            put_byte(pb, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */

            /* look for sps and pps */
            while (buf < end) {
                unsigned int size;
                uint8_t nal_type;
                size = BE_32(buf);
                nal_type = buf[4] & 0x1f;
                if (nal_type == 7) { /* SPS */
                    sps = buf + 4;
                    sps_size = size;
                } else if (nal_type == 8) { /* PPS */
                    pps = buf + 4;
                    pps_size = size;
                }
                buf += size + 4;
            }
            assert(sps);
            assert(pps);
            put_be16(pb, sps_size);
            put_buffer(pb, sps, sps_size);
            put_byte(pb, 1); /* number of pps */
            put_be16(pb, pps_size);