movenc.c

来自「ffmpeg的完整源代码和作者自己写的文档。不但有在Linux的工程哦」· C语言 代码 · 共 1,708 行 · 第 1/4 页

            if( p[3] == 0 ) {
                if( p[2] == 0 && p[4] == 1 )
                    return p+1;
                if( p[4] == 0 && p[5] == 1 )
                    return p+2;
            }
        }
    }

    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 (AV_RB32(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;

            /* look for sps and pps */
            while (buf < end) {
                unsigned int size;
                uint8_t nal_type;
                size = AV_RB32(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_byte(pb, 1); /* version */
            put_byte(pb, sps[1]); /* profile */
            put_byte(pb, sps[2]); /* profile compat */
            put_byte(pb, sps[3]); /* 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) */

            put_be16(pb, sps_size);
            put_buffer(pb, sps, sps_size);
            put_byte(pb, 1); /* number of pps */
            put_be16(pb, pps_size);
            put_buffer(pb, pps, pps_size);
        } else {
            put_buffer(pb, track->vosData, track->vosLen);
        }
    }
    return updateSize(pb, pos);
}

static int mov_find_video_codec_tag(AVFormatContext *s, MOVTrack *track)
{
    int tag = track->enc->codec_tag;
    if (!tag) {
        if (track->enc->codec_id == CODEC_ID_DVVIDEO) {
            if (track->enc->height == 480) { /* NTSC */
                if (track->enc->pix_fmt == PIX_FMT_YUV422P)
                    tag = MKTAG('d', 'v', '5', 'n');
                else
                    tag = MKTAG('d', 'v', 'c', ' ');
            } else { /* assume PAL */
                if (track->enc->pix_fmt == PIX_FMT_YUV422P)
                    tag = MKTAG('d', 'v', '5', 'p');
                else if (track->enc->pix_fmt == PIX_FMT_YUV420P)
                    tag = MKTAG('d', 'v', 'c', 'p');
                else
                    tag = MKTAG('d', 'v', 'p', 'p');
            }
        } else if (track->enc->codec_id == CODEC_ID_H263) {
            if (track->mode == MODE_MOV)
                tag = MKTAG('h', '2', '6', '3');
            else
                tag = MKTAG('s', '2', '6', '3');
        } else {
            tag = codec_get_tag(codec_movvideo_tags, track->enc->codec_id);
        }
    }
    // if no mac fcc found, try with Microsoft tags
    if (!tag) {
        tag = codec_get_tag(codec_bmp_tags, track->enc->codec_id);
        if (tag) {
            av_log(s, AV_LOG_INFO, "Warning, using MS style video codec tag, the file may be unplayable!\n");
        }
    }
    assert(tag);
    return tag;
}

static int mov_find_audio_codec_tag(AVFormatContext *s, MOVTrack *track)
{
    int 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 ms_tag = codec_get_tag(codec_wav_tags, track->enc->codec_id);
        if (ms_tag) {
            tag = MKTAG('m', 's', ((ms_tag >> 8) & 0xff), (ms_tag & 0xff));
            av_log(s, AV_LOG_INFO, "Warning, using MS style audio codec tag, the file may be unplayable!\n");
        }
    }
    assert(tag);
    return tag;
}

static int mov_write_video_tag(ByteIOContext *pb, MOVTrack* track)
{
    offset_t pos = url_ftell(pb);
    char compressor_name[32];

    put_be32(pb, 0); /* size */
    put_le32(pb, track->tag); // store it byteswapped
    put_be32(pb, 0); /* Reserved */
    put_be16(pb, 0); /* Reserved */
    put_be16(pb, 1); /* Data-reference index */

    put_be16(pb, 0); /* Codec stream version */
    put_be16(pb, 0); /* Codec stream revision (=0) */
    if (track->mode == MODE_MOV) {
        put_tag(pb, "FFMP"); /* Vendor */
        if(track->enc->codec_id == CODEC_ID_RAWVIDEO) {
            put_be32(pb, 0); /* Temporal Quality */
            put_be32(pb, 0x400); /* Spatial Quality = lossless*/
        } else {
            put_be32(pb, 0x200); /* Temporal Quality = normal */
            put_be32(pb, 0x200); /* Spatial Quality = normal */
        }
    } else {
        put_be32(pb, 0); /* Reserved */
        put_be32(pb, 0); /* Reserved */
        put_be32(pb, 0); /* Reserved */
    }
    put_be16(pb, track->enc->width); /* Video width */
    put_be16(pb, track->enc->height); /* Video height */
    put_be32(pb, 0x00480000); /* Horizontal resolution 72dpi */
    put_be32(pb, 0x00480000); /* Vertical resolution 72dpi */
    put_be32(pb, 0); /* Data size (= 0) */
    put_be16(pb, 1); /* Frame count (= 1) */

    memset(compressor_name,0,32);
    /* FIXME not sure, ISO 14496-1 draft where it shall be set to 0 */
    if (track->mode == MODE_MOV && track->enc->codec && track->enc->codec->name)
        strncpy(compressor_name,track->enc->codec->name,31);
    put_byte(pb, strlen(compressor_name));
    put_buffer(pb, compressor_name, 31);

    put_be16(pb, 0x18); /* Reserved */
    put_be16(pb, 0xffff); /* Reserved */
    if(track->enc->codec_id == CODEC_ID_MPEG4)
        mov_write_esds_tag(pb, track);
    else if(track->enc->codec_id == CODEC_ID_H263)
        mov_write_d263_tag(pb);
    else if(track->enc->codec_id == CODEC_ID_SVQ3)
        mov_write_svq3_tag(pb);
    else if(track->enc->codec_id == CODEC_ID_H264)
        mov_write_avcc_tag(pb, track);

    return updateSize (pb, pos);
}

static int mov_write_stsd_tag(ByteIOContext *pb, MOVTrack* track)
{
    offset_t pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "stsd");
    put_be32(pb, 0); /* version & flags */
    put_be32(pb, 1); /* entry count */
    if (track->enc->codec_type == CODEC_TYPE_VIDEO)
        mov_write_video_tag(pb, track);
    else if (track->enc->codec_type == CODEC_TYPE_AUDIO)
        mov_write_audio_tag(pb, track);
    return updateSize(pb, pos);
}

static int mov_write_ctts_tag(ByteIOContext *pb, MOVTrack* track)
{
    MOV_stts_t *ctts_entries;
    uint32_t entries = 0;
    uint32_t atom_size;
    int i;

    ctts_entries = av_malloc((track->entry + 1) * sizeof(*ctts_entries)); /* worst case */
    ctts_entries[0].count = 1;
    ctts_entries[0].duration = track->cluster[0].cts;
    for (i=1; i<track->entry; i++) {
        if (track->cluster[i].cts == ctts_entries[entries].duration) {
            ctts_entries[entries].count++; /* compress */
        } else {
            entries++;
            ctts_entries[entries].duration = track->cluster[i].cts;
            ctts_entries[entries].count = 1;
        }
    }
    entries++; /* last one */
    atom_size = 16 + (entries * 8);
    put_be32(pb, atom_size); /* size */
    put_tag(pb, "ctts");
    put_be32(pb, 0); /* version & flags */
    put_be32(pb, entries); /* entry count */
    for (i=0; i<entries; i++) {
        put_be32(pb, ctts_entries[i].count);
        put_be32(pb, ctts_entries[i].duration);
    }
    av_free(ctts_entries);
    return atom_size;
}

/* Time to sample atom */
static int mov_write_stts_tag(ByteIOContext *pb, MOVTrack* track)
{
    MOV_stts_t *stts_entries;
    uint32_t entries = -1;
    uint32_t atom_size;
    int i;

    if (track->enc->codec_type == CODEC_TYPE_AUDIO && !track->audio_vbr) {
        stts_entries = av_malloc(sizeof(*stts_entries)); /* one entry */
        stts_entries[0].count = track->sampleCount;
        stts_entries[0].duration = 1;
        entries = 1;
    } else {
        stts_entries = av_malloc(track->entry * sizeof(*stts_entries)); /* worst case */
        for (i=0; i<track->entry; i++) {
            int64_t duration = i + 1 == track->entry ?
                track->trackDuration - track->cluster[i].dts + track->cluster[0].dts : /* readjusting */
                track->cluster[i+1].dts - track->cluster[i].dts;
            if (i && duration == stts_entries[entries].duration) {
                stts_entries[entries].count++; /* compress */
            } else {
                entries++;
                stts_entries[entries].duration = duration;
                stts_entries[entries].count = 1;
            }
        }
        entries++; /* last one */
    }
    atom_size = 16 + (entries * 8);
    put_be32(pb, atom_size); /* size */
    put_tag(pb, "stts");
    put_be32(pb, 0); /* version & flags */
    put_be32(pb, entries); /* entry count */
    for (i=0; i<entries; i++) {
        put_be32(pb, stts_entries[i].count);
        put_be32(pb, stts_entries[i].duration);
    }
    av_free(stts_entries);
    return atom_size;
}

static int mov_write_dref_tag(ByteIOContext *pb)
{
    put_be32(pb, 28); /* size */
    put_tag(pb, "dref");
    put_be32(pb, 0); /* version & flags */
    put_be32(pb, 1); /* entry count */

    put_be32(pb, 0xc); /* size */
    put_tag(pb, "url ");
    put_be32(pb, 1); /* version & flags */

    return 28;
}

static int mov_write_stbl_tag(ByteIOContext *pb, MOVTrack* track)
{
    offset_t pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "stbl");
    mov_write_stsd_tag(pb, track);
    mov_write_stts_tag(pb, track);
    if (track->enc->codec_type == CODEC_TYPE_VIDEO &&
        track->hasKeyframes < track->entry)
        mov_write_stss_tag(pb, track);
    if (track->enc->codec_type == CODEC_TYPE_VIDEO &&
        track->hasBframes)
        mov_write_ctts_tag(pb, track);
    mov_write_stsc_tag(pb, track);
    mov_write_stsz_tag(pb, track);
    mov_write_stco_tag(pb, track);
    return updateSize(pb, pos);
}

static int mov_write_dinf_tag(ByteIOContext *pb)
{
    offset_t pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "dinf");
    mov_write_dref_tag(pb);
    return updateSize(pb, pos);
}

static int mov_write_smhd_tag(ByteIOContext *pb)
{
    put_be32(pb, 16); /* size */
    put_tag(pb, "smhd");
    put_be32(pb, 0); /* version & flags */
    put_be16(pb, 0); /* reserved (balance, normally = 0) */
    put_be16(pb, 0); /* reserved */
    return 16;
}

static int mov_write_vmhd_tag(ByteIOContext *pb)
{
    put_be32(pb, 0x14); /* size (always 0x14) */
    put_tag(pb, "vmhd");
    put_be32(pb, 0x01); /* version & flags */
    put_be64(pb, 0); /* reserved (graphics mode = copy) */
    return 0x14;
}

static int mov_write_hdlr_tag(ByteIOContext *pb, MOVTrack* track)
{
    const char *descr, *hdlr, *hdlr_type;
    offset_t pos = url_ftell(pb);

    if (!track) { /* no media --> data handler */
        hdlr = "dhlr";
        hdlr_type = "url ";
        descr = "DataHandler";
    } else {
        hdlr = (track->mode == MODE_MOV) ? "mhlr" : "\0\0\0\0";
        if (track->enc->codec_type == CODEC_TYPE_VIDEO) {
            hdlr_type = "vide";
            descr = "VideoHandler";
        } else {
            hdlr_type = "soun";
            descr = "SoundHandler";
        }
    }

    put_be32(pb, 0); /* size */
    put_tag(pb, "hdlr");
    put_be32(pb, 0); /* Version & flags */
    put_buffer(pb, hdlr, 4); /* handler */
    put_tag(pb, hdlr_type); /* handler type */
    put_be32(pb ,0); /* reserved */
    put_be32(pb ,0); /* reserved */
    put_be32(pb ,0); /* reserved */
    put_byte(pb, strlen(descr)); /* string counter */
    put_buffer(pb, descr, strlen(descr)); /* handler description */
    return updateSize(pb, pos);
}

static int mov_write_minf_tag(ByteIOContext *pb, MOVTrack* track)
{
    offset_t pos = url_ftell(pb);
    put_be32(pb, 0); /* size */
    put_tag(pb, "minf");
    if(track->enc->codec_type == CODEC_TYPE_VIDEO)
        mov_write_vmhd_tag(pb);
    else
        mov_write_smhd_tag(pb);
    if (track->mode == MODE_MOV) /* FIXME: Why do it for MODE_MOV only ? */
        mov_write_hdlr_tag(pb, NULL);
    mov_write_dinf_tag(pb);
    mov_write_stbl_tag(pb, track);
    return updateSize(pb, pos);
}

static int mov_write_mdhd_tag(ByteIOContext *pb, MOVTrack* track)
{
    int version = track->trackDuration < INT32_MAX ? 0 : 1;

    (version == 1) ? put_be32(pb, 44) : put_be32(pb, 32); /* size */
    put_tag(pb, "mdhd");
    put_byte(pb, version);
    put_be24(pb, 0); /* flags */
    if (version == 1) {
        put_be64(pb, track->time);
        put_be64(pb, track->time);
    } else {
        put_be32(pb, track->time); /* creation time */
        put_be32(pb, track->time); /* modification time */
    }
    put_be32(pb, track->timescale); /* time scale (sample rate for audio) */
    (version == 1) ? put_be64(pb, track->trackDuration) : put_be32(pb, track->trackDuration); /* duration */
    put_be16(pb, track->language); /* language */
    put_be16(pb, 0); /* reserved (quality) */

    if(version!=0 && track->mode == MODE_MOV){
        av_log(NULL, AV_LOG_ERROR,
            "FATAL error, file duration too long for timebase, this file will not be\n"
            "playable with quicktime. Choose a different timebase or a different\n"
            "container format\n");
    }