Function dv_write_pack

libavformat/dvenc.c:98–188

}

static int dv_write_pack(enum DVPackType pack_id, DVMuxContext *c, uint8_t* buf, int channel, int seq)
{
    struct tm tc;
    time_t ct;
    uint32_t timecode;
    int audio_type = 0;

    buf[0] = (uint8_t)pack_id;
    switch (pack_id) {
    case DV_TIMECODE:
        timecode  = av_timecode_get_smpte_from_framenum(&c->tc, c->frames);
        timecode |= 1<<23 | 1<<15 | 1<<7 | 1<<6; // biphase and binary group flags
        AV_WB32(buf + 1, timecode);
        break;
    case DV_AUDIO_SOURCE:  /* AAUX source pack */
        if (c->ast[channel]->codecpar->sample_rate == 44100) {
            audio_type = 1;
        } else if (c->ast[channel]->codecpar->sample_rate == 32000)
            audio_type = 2;
        buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
                 (1 << 6) | /* reserved -- always 1 */
                 (dv_audio_frame_size(c->sys, c->frames, c->ast[channel]->codecpar->sample_rate) -
                  c->sys->audio_min_samples[audio_type]);
                            /* # of samples      */
        buf[2] = (0 << 7) | /* multi-stereo      */
                 (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
                 (0 << 4) | /* pair bit: 0 -- one pair of channels */
                 (seq >= c->sys->difseg_size/2); /* audio mode (1st or 2nd channel) */
        buf[3] = (1 << 7) | /* res               */
                 (1 << 6) | /* multi-language flag */
                 (c->sys->dsf << 5) | /*  system: 60fields/50fields */
                 (DV_PROFILE_IS_HD(c->sys) ? 0x3 : c->sys->video_stype ? 2 : 0); /* stype */
        buf[4] = (1 << 7) | /* emphasis: 1 -- off */
                 (0 << 6) | /* emphasis time constant: 0 -- reserved */
                 (audio_type << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
                  0;        /* quantization: 0 -- 16-bit linear, 1 -- 12-bit nonlinear */

        break;
    case DV_AUDIO_CONTROL:
        buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
                 (1 << 4) | /* input source: 1 -- digital input */
                 (3 << 2) | /* compression: 3 -- no information */
                  0;        /* misc. info/SMPTE emphasis off */
        buf[2] = (1 << 7) | /* recording start point: 1 -- no */
                 (1 << 6) | /* recording end point: 1 -- no */
                 (1 << 3) | /* recording mode: 1 -- original */
                  7;
        buf[3] = (1 << 7) | /* direction: 1 -- forward */
                 (c->sys->pix_fmt == AV_PIX_FMT_YUV420P ? 0x20 : /* speed */
                                                       c->sys->ltc_divisor * 4);
        buf[4] = (1 << 7) | /* reserved -- always 1 */
                  0x7f;     /* genre category */
        break;
    case DV_AUDIO_RECDATE:
    case DV_VIDEO_RECDATE:  /* VAUX recording date */
        ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
                                            c->sys->time_base.den, AV_ROUND_DOWN);
        brktimegm(ct, &tc);