Function alignStreams

libhb/sync.c:558–623

}

static void alignStreams( sync_common_t * common, int64_t pts )
{
    int           ii;
    hb_buffer_t * buf;

    if (common->job->align_av_start)
    {
        int64_t first_pts = AV_NOPTS_VALUE;
        int     audio_passthru = 0;

        for (ii = 0; ii < common->stream_count; ii++)
        {
            sync_stream_t * stream = &common->streams[ii];

            buf = hb_list_item(stream->in_queue, 0);

            // P-to-P encoding will pass the start point in pts.
            // Drop any buffers that are before the start point.
            while (buf != NULL && buf->s.start < pts)
            {
                hb_list_rem(stream->in_queue, buf);
                hb_buffer_close(&buf);
                buf = hb_list_item(stream->in_queue, 0);
            }
            if (buf == NULL)
            {
                continue;
            }
            if (stream->type == SYNC_TYPE_AUDIO &&
                stream->audio.audio->config.out.codec & HB_ACODEC_PASS_FLAG)
            {
                // Find the largest initial pts of all passthru audio streams.
                // We can not add silence to passthru audio streams.
                // To align with a passthru audio stream, we must drop
                // buffers from all other streams that are before
                // the first buffer in the passthru audio stream.
                audio_passthru = 1;
                if (first_pts < buf->s.start)
                {
                    first_pts = buf->s.start;
                }
            }
            else if (!audio_passthru)
            {
                // Find the smallest initial pts of all streams when
                // there is *no* passthru audio.
                // When there is no passthru audio stream, we insert
                // silence or black buffers to fill any gaps between
                // the start of any stream and the start of the stream
                // with the smallest pts.
                if (first_pts == AV_NOPTS_VALUE || first_pts > buf->s.start)
                {
                    first_pts = buf->s.start;
                }
            }
        }
        if (first_pts != AV_NOPTS_VALUE)
        {