void ff_af_queue_remove(AudioFrameQueue *afq, int nb_samples, int64_t *pts,
                        int *duration)
{
    int64_t out_pts = AV_NOPTS_VALUE;
    int removed_samples = 0;

#ifdef DEBUG
    ff_af_queue_log_state(afq);
#endif

    /* get output pts from the next frame or generated pts */
    if (afq->frame_queue) {
        if (afq->frame_queue->pts != AV_NOPTS_VALUE)
            out_pts = afq->frame_queue->pts - afq->remaining_delay;
    } else {
        if (afq->next_pts != AV_NOPTS_VALUE)
            out_pts = afq->next_pts - afq->remaining_delay;
    }
    if (pts) {
        if (out_pts != AV_NOPTS_VALUE)
            *pts = ff_samples_to_time_base(afq->avctx, out_pts);
        else
            *pts = AV_NOPTS_VALUE;
    }

    /* if the delay is larger than the packet duration, we use up delay samples
       for the output packet and leave all frames in the queue */
    if (afq->remaining_delay >= nb_samples) {
        removed_samples      += nb_samples;
        afq->remaining_delay -= nb_samples;
    }
    /* remove frames from the queue until we have enough to cover the
       requested number of samples or until the queue is empty */
    while (removed_samples < nb_samples && afq->frame_queue) {
        removed_samples += afq->frame_queue->duration;
        delete_next_frame(afq);
    }
    afq->remaining_samples -= removed_samples;

    /* if there are no frames left and we have room for more samples, use
       any remaining delay samples */
    if (removed_samples < nb_samples && afq->remaining_samples > 0) {
        int add_samples = FFMIN(afq->remaining_samples,
                                nb_samples - removed_samples);
        removed_samples        += add_samples;
        afq->remaining_samples -= add_samples;
    }
    if (removed_samples > nb_samples)
        av_log(afq->avctx, AV_LOG_WARNING, "frame_size is too large\n");
    if (duration)
        *duration = ff_samples_to_time_base(afq->avctx, removed_samples);
}