Exemplo n.º 1
0
static BOOL ffmpeg_resample_frame(AVAudioResampleContext* context,
                                  AVFrame* in, AVFrame* out)
{
	int ret;

	if (!avresample_is_open(context))
	{
		if ((ret = avresample_config(context, out, in)) < 0)
		{
			const char* err = av_err2str(ret);
			WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
			return FALSE;
		}

		if ((ret = (avresample_open(context))) < 0)
		{
			const char* err = av_err2str(ret);
			WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
			return FALSE;
		}
	}

	if ((ret = avresample_convert_frame(context, out, in)) < 0)
	{
		const char* err = av_err2str(ret);
		WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
		return FALSE;
	}

	return TRUE;
}
Exemplo n.º 2
0
static BOOL ffmpeg_decode(AVCodecContext* dec_ctx, AVPacket* pkt,
                          AVFrame* frame,
                          AVAudioResampleContext* resampleContext,
                          AVFrame* resampled, wStream* out)
{
	int ret;
	/* send the packet with the compressed data to the decoder */
	ret = avcodec_send_packet(dec_ctx, pkt);

	if (ret < 0)
	{
		const char* err = av_err2str(ret);
		WLog_ERR(TAG, "Error submitting the packet to the decoder %s [%d]",
		         err, ret);
		return FALSE;
	}

	/* read all the output frames (in general there may be any number of them */
	while (ret >= 0)
	{
		ret = avcodec_receive_frame(dec_ctx, frame);

		if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
			return TRUE;
		else if (ret < 0)
		{
			const char* err = av_err2str(ret);
			WLog_ERR(TAG, "Error during decoding %s [%d]", err, ret);
			return FALSE;
		}

		if (!avresample_is_open(resampleContext))
		{
			if ((ret = avresample_config(resampleContext, resampled, frame)) < 0)
			{
				const char* err = av_err2str(ret);
				WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
				return FALSE;
			}

			if ((ret = (avresample_open(resampleContext))) < 0)
			{
				const char* err = av_err2str(ret);
				WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
				return FALSE;
			}
		}

		if ((ret = avresample_convert_frame(resampleContext, resampled, frame)) < 0)
		{
			const char* err = av_err2str(ret);
			WLog_ERR(TAG, "Error during resampling %s [%d]", err, ret);
			return FALSE;
		}

		{
			const size_t data_size = resampled->channels * resampled->nb_samples * 2;
			Stream_EnsureRemainingCapacity(out, data_size);
			Stream_Write(out, resampled->data[0], data_size);
		}
	}

	return TRUE;
}
Exemplo n.º 3
0
int avresample_open(AVAudioResampleContext *avr)
{
    int ret;

    if (avresample_is_open(avr)) {
        av_log(avr, AV_LOG_ERROR, "The resampling context is already open.\n");
        return AVERROR(EINVAL);
    }

    /* set channel mixing parameters */
    avr->in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
    if (avr->in_channels <= 0 || avr->in_channels > AVRESAMPLE_MAX_CHANNELS) {
        av_log(avr, AV_LOG_ERROR, "Invalid input channel layout: %"PRIu64"\n",
               avr->in_channel_layout);
        return AVERROR(EINVAL);
    }
    avr->out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
    if (avr->out_channels <= 0 || avr->out_channels > AVRESAMPLE_MAX_CHANNELS) {
        av_log(avr, AV_LOG_ERROR, "Invalid output channel layout: %"PRIu64"\n",
               avr->out_channel_layout);
        return AVERROR(EINVAL);
    }
    avr->resample_channels = FFMIN(avr->in_channels, avr->out_channels);
    avr->downmix_needed    = avr->in_channels  > avr->out_channels;
    avr->upmix_needed      = avr->out_channels > avr->in_channels ||
                             (!avr->downmix_needed && (avr->mix_matrix ||
                              avr->in_channel_layout != avr->out_channel_layout));
    avr->mixing_needed     = avr->downmix_needed || avr->upmix_needed;

    /* set resampling parameters */
    avr->resample_needed   = avr->in_sample_rate != avr->out_sample_rate ||
                             avr->force_resampling;

    /* select internal sample format if not specified by the user */
    if (avr->internal_sample_fmt == AV_SAMPLE_FMT_NONE &&
        (avr->mixing_needed || avr->resample_needed)) {
        enum AVSampleFormat  in_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
        enum AVSampleFormat out_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
        int max_bps = FFMAX(av_get_bytes_per_sample(in_fmt),
                            av_get_bytes_per_sample(out_fmt));
        if (max_bps <= 2) {
            avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;
        } else if (avr->mixing_needed) {
            avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
        } else {
            if (max_bps <= 4) {
                if (in_fmt  == AV_SAMPLE_FMT_S32P ||
                    out_fmt == AV_SAMPLE_FMT_S32P) {
                    if (in_fmt  == AV_SAMPLE_FMT_FLTP ||
                        out_fmt == AV_SAMPLE_FMT_FLTP) {
                        /* if one is s32 and the other is flt, use dbl */
                        avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
                    } else {
                        /* if one is s32 and the other is s32, s16, or u8, use s32 */
                        avr->internal_sample_fmt = AV_SAMPLE_FMT_S32P;
                    }
                } else {
                    /* if one is flt and the other is flt, s16 or u8, use flt */
                    avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
                }
            } else {
                /* if either is dbl, use dbl */
                avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
            }
        }
        av_log(avr, AV_LOG_DEBUG, "Using %s as internal sample format\n",
               av_get_sample_fmt_name(avr->internal_sample_fmt));
    }

    /* treat all mono as planar for easier comparison */
    if (avr->in_channels == 1)
        avr->in_sample_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
    if (avr->out_channels == 1)
        avr->out_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);

    /* we may need to add an extra conversion in order to remap channels if
       the output format is not planar */
    if (avr->use_channel_map && !avr->mixing_needed && !avr->resample_needed &&
        !av_sample_fmt_is_planar(avr->out_sample_fmt)) {
        avr->internal_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
    }

    /* set sample format conversion parameters */
    if (avr->resample_needed || avr->mixing_needed)
        avr->in_convert_needed = avr->in_sample_fmt != avr->internal_sample_fmt;
    else
        avr->in_convert_needed = avr->use_channel_map &&
                                 !av_sample_fmt_is_planar(avr->out_sample_fmt);

    if (avr->resample_needed || avr->mixing_needed || avr->in_convert_needed)
        avr->out_convert_needed = avr->internal_sample_fmt != avr->out_sample_fmt;
    else
        avr->out_convert_needed = avr->in_sample_fmt != avr->out_sample_fmt;

    avr->in_copy_needed = !avr->in_convert_needed && (avr->mixing_needed ||
                          (avr->use_channel_map && avr->resample_needed));

    if (avr->use_channel_map) {
        if (avr->in_copy_needed) {
            avr->remap_point = REMAP_IN_COPY;
            av_dlog(avr, "remap channels during in_copy\n");
        } else if (avr->in_convert_needed) {
            avr->remap_point = REMAP_IN_CONVERT;
            av_dlog(avr, "remap channels during in_convert\n");
        } else if (avr->out_convert_needed) {
            avr->remap_point = REMAP_OUT_CONVERT;
            av_dlog(avr, "remap channels during out_convert\n");
        } else {
            avr->remap_point = REMAP_OUT_COPY;
            av_dlog(avr, "remap channels during out_copy\n");
        }

#ifdef DEBUG
        {
            int ch;
            av_dlog(avr, "output map: ");
            if (avr->ch_map_info.do_remap)
                for (ch = 0; ch < avr->in_channels; ch++)
                    av_dlog(avr, " % 2d", avr->ch_map_info.channel_map[ch]);
            else
                av_dlog(avr, "n/a");
            av_dlog(avr, "\n");
            av_dlog(avr, "copy map:   ");
            if (avr->ch_map_info.do_copy)
                for (ch = 0; ch < avr->in_channels; ch++)
                    av_dlog(avr, " % 2d", avr->ch_map_info.channel_copy[ch]);
            else
                av_dlog(avr, "n/a");
            av_dlog(avr, "\n");
            av_dlog(avr, "zero map:   ");
            if (avr->ch_map_info.do_zero)
                for (ch = 0; ch < avr->in_channels; ch++)
                    av_dlog(avr, " % 2d", avr->ch_map_info.channel_zero[ch]);
            else
                av_dlog(avr, "n/a");
            av_dlog(avr, "\n");
            av_dlog(avr, "input map:  ");
            for (ch = 0; ch < avr->in_channels; ch++)
                av_dlog(avr, " % 2d", avr->ch_map_info.input_map[ch]);
            av_dlog(avr, "\n");
        }
#endif
    } else
        avr->remap_point = REMAP_NONE;

    /* allocate buffers */
    if (avr->in_copy_needed || avr->in_convert_needed) {
        avr->in_buffer = ff_audio_data_alloc(FFMAX(avr->in_channels, avr->out_channels),
                                             0, avr->internal_sample_fmt,
                                             "in_buffer");
        if (!avr->in_buffer) {
            ret = AVERROR(EINVAL);
            goto error;
        }
    }
    if (avr->resample_needed) {
        avr->resample_out_buffer = ff_audio_data_alloc(avr->out_channels,
                                                       1024, avr->internal_sample_fmt,
                                                       "resample_out_buffer");
        if (!avr->resample_out_buffer) {
            ret = AVERROR(EINVAL);
            goto error;
        }
    }
    if (avr->out_convert_needed) {
        avr->out_buffer = ff_audio_data_alloc(avr->out_channels, 0,
                                              avr->out_sample_fmt, "out_buffer");
        if (!avr->out_buffer) {
            ret = AVERROR(EINVAL);
            goto error;
        }
    }
    avr->out_fifo = av_audio_fifo_alloc(avr->out_sample_fmt, avr->out_channels,
                                        1024);
    if (!avr->out_fifo) {
        ret = AVERROR(ENOMEM);
        goto error;
    }

    /* setup contexts */
    if (avr->in_convert_needed) {
        avr->ac_in = ff_audio_convert_alloc(avr, avr->internal_sample_fmt,
                                            avr->in_sample_fmt, avr->in_channels,
                                            avr->in_sample_rate,
                                            avr->remap_point == REMAP_IN_CONVERT);
        if (!avr->ac_in) {
            ret = AVERROR(ENOMEM);
            goto error;
        }
    }
    if (avr->out_convert_needed) {
        enum AVSampleFormat src_fmt;
        if (avr->in_convert_needed)
            src_fmt = avr->internal_sample_fmt;
        else
            src_fmt = avr->in_sample_fmt;
        avr->ac_out = ff_audio_convert_alloc(avr, avr->out_sample_fmt, src_fmt,
                                             avr->out_channels,
                                             avr->out_sample_rate,
                                             avr->remap_point == REMAP_OUT_CONVERT);
        if (!avr->ac_out) {
            ret = AVERROR(ENOMEM);
            goto error;
        }
    }
    if (avr->resample_needed) {
        avr->resample = ff_audio_resample_init(avr);
        if (!avr->resample) {
            ret = AVERROR(ENOMEM);
            goto error;
        }
    }
    if (avr->mixing_needed) {
        avr->am = ff_audio_mix_alloc(avr);
        if (!avr->am) {
            ret = AVERROR(ENOMEM);
            goto error;
        }
    }

    return 0;

error:
    avresample_close(avr);
    return ret;
}
Exemplo n.º 4
0
static int opus_decode_subpacket(OpusStreamContext *s,
                                 const uint8_t *buf, int buf_size,
                                 int nb_samples)
{
    int output_samples = 0;
    int flush_needed   = 0;
    int i, j, ret;

    /* check if we need to flush the resampler */
    if (avresample_is_open(s->avr)) {
        if (buf) {
            int64_t cur_samplerate;
            av_opt_get_int(s->avr, "in_sample_rate", 0, &cur_samplerate);
            flush_needed = (s->packet.mode == OPUS_MODE_CELT) || (cur_samplerate != s->silk_samplerate);
        } else {
            flush_needed = !!s->delayed_samples;
        }
    }

    if (!buf && !flush_needed)
        return 0;

    /* use dummy output buffers if the channel is not mapped to anything */
    if (!s->out[0] ||
        (s->output_channels == 2 && !s->out[1])) {
        av_fast_malloc(&s->out_dummy, &s->out_dummy_allocated_size, s->out_size);
        if (!s->out_dummy)
            return AVERROR(ENOMEM);
        if (!s->out[0])
            s->out[0] = s->out_dummy;
        if (!s->out[1])
            s->out[1] = s->out_dummy;
    }

    /* flush the resampler if necessary */
    if (flush_needed) {
        ret = opus_flush_resample(s, s->delayed_samples);
        if (ret < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error flushing the resampler.\n");
            return ret;
        }
        avresample_close(s->avr);
        output_samples += s->delayed_samples;
        s->delayed_samples = 0;

        if (!buf)
            goto finish;
    }

    /* decode all the frames in the packet */
    for (i = 0; i < s->packet.frame_count; i++) {
        int size = s->packet.frame_size[i];
        int samples = opus_decode_frame(s, buf + s->packet.frame_offset[i], size);

        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error decoding an Opus frame.\n");
            if (s->avctx->err_recognition & AV_EF_EXPLODE)
                return samples;

            for (j = 0; j < s->output_channels; j++)
                memset(s->out[j], 0, s->packet.frame_duration * sizeof(float));
            samples = s->packet.frame_duration;
        }
        output_samples += samples;

        for (j = 0; j < s->output_channels; j++)
            s->out[j] += samples;
        s->out_size -= samples * sizeof(float);
    }

finish:
    s->out[0] = s->out[1] = NULL;
    s->out_size = 0;

    return output_samples;
}
Exemplo n.º 5
0
static int opus_decode_frame(OpusStreamContext *s, const uint8_t *data, int size)
{
    int samples    = s->packet.frame_duration;
    int redundancy = 0;
    int redundancy_size, redundancy_pos;
    int ret, i, consumed;
    int delayed_samples = s->delayed_samples;

    ret = opus_rc_init(&s->rc, data, size);
    if (ret < 0)
        return ret;

    /* decode the silk frame */
    if (s->packet.mode == OPUS_MODE_SILK || s->packet.mode == OPUS_MODE_HYBRID) {
        if (!avresample_is_open(s->avr)) {
            ret = opus_init_resample(s);
            if (ret < 0)
                return ret;
        }

        samples = ff_silk_decode_superframe(s->silk, &s->rc, s->silk_output,
                                            FFMIN(s->packet.bandwidth, OPUS_BANDWIDTH_WIDEBAND),
                                            s->packet.stereo + 1,
                                            silk_frame_duration_ms[s->packet.config]);
        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error decoding a SILK frame.\n");
            return samples;
        }

        samples = avresample_convert(s->avr, (uint8_t**)s->out, s->out_size,
                                     s->packet.frame_duration,
                                     (uint8_t**)s->silk_output,
                                     sizeof(s->silk_buf[0]),
                                     samples);
        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error resampling SILK data.\n");
            return samples;
        }
        s->delayed_samples += s->packet.frame_duration - samples;
    } else
        ff_silk_flush(s->silk);

    // decode redundancy information
    consumed = opus_rc_tell(&s->rc);
    if (s->packet.mode == OPUS_MODE_HYBRID && consumed + 37 <= size * 8)
        redundancy = opus_rc_p2model(&s->rc, 12);
    else if (s->packet.mode == OPUS_MODE_SILK && consumed + 17 <= size * 8)
        redundancy = 1;

    if (redundancy) {
        redundancy_pos = opus_rc_p2model(&s->rc, 1);

        if (s->packet.mode == OPUS_MODE_HYBRID)
            redundancy_size = opus_rc_unimodel(&s->rc, 256) + 2;
        else
            redundancy_size = size - (consumed + 7) / 8;
        size -= redundancy_size;
        if (size < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid redundancy frame size.\n");
            return AVERROR_INVALIDDATA;
        }

        if (redundancy_pos) {
            ret = opus_decode_redundancy(s, data + size, redundancy_size);
            if (ret < 0)
                return ret;
            ff_celt_flush(s->celt);
        }
    }

    /* decode the CELT frame */
    if (s->packet.mode == OPUS_MODE_CELT || s->packet.mode == OPUS_MODE_HYBRID) {
        float *out_tmp[2] = { s->out[0], s->out[1] };
        float **dst = (s->packet.mode == OPUS_MODE_CELT) ?
                      out_tmp : s->celt_output;
        int celt_output_samples = samples;
        int delay_samples = av_audio_fifo_size(s->celt_delay);

        if (delay_samples) {
            if (s->packet.mode == OPUS_MODE_HYBRID) {
                av_audio_fifo_read(s->celt_delay, (void**)s->celt_output, delay_samples);

                for (i = 0; i < s->output_channels; i++) {
                    s->fdsp->vector_fmac_scalar(out_tmp[i], s->celt_output[i], 1.0,
                                                delay_samples);
                    out_tmp[i] += delay_samples;
                }
                celt_output_samples -= delay_samples;
            } else {
                av_log(s->avctx, AV_LOG_WARNING,
                       "Spurious CELT delay samples present.\n");
                av_audio_fifo_drain(s->celt_delay, delay_samples);
                if (s->avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_BUG;
            }
        }

        opus_raw_init(&s->rc, data + size, size);

        ret = ff_celt_decode_frame(s->celt, &s->rc, dst,
                                   s->packet.stereo + 1,
                                   s->packet.frame_duration,
                                   (s->packet.mode == OPUS_MODE_HYBRID) ? 17 : 0,
                                   celt_band_end[s->packet.bandwidth]);
        if (ret < 0)
            return ret;

        if (s->packet.mode == OPUS_MODE_HYBRID) {
            int celt_delay = s->packet.frame_duration - celt_output_samples;
            void *delaybuf[2] = { s->celt_output[0] + celt_output_samples,
                                  s->celt_output[1] + celt_output_samples };

            for (i = 0; i < s->output_channels; i++) {
                s->fdsp->vector_fmac_scalar(out_tmp[i],
                                            s->celt_output[i], 1.0,
                                            celt_output_samples);
            }

            ret = av_audio_fifo_write(s->celt_delay, delaybuf, celt_delay);
            if (ret < 0)
                return ret;
        }
    } else
        ff_celt_flush(s->celt);

    if (s->redundancy_idx) {
        for (i = 0; i < s->output_channels; i++)
            opus_fade(s->out[i], s->out[i],
                      s->redundancy_output[i] + 120 + s->redundancy_idx,
                      ff_celt_window2 + s->redundancy_idx, 120 - s->redundancy_idx);
        s->redundancy_idx = 0;
    }
    if (redundancy) {
        if (!redundancy_pos) {
            ff_celt_flush(s->celt);
            ret = opus_decode_redundancy(s, data + size, redundancy_size);
            if (ret < 0)
                return ret;

            for (i = 0; i < s->output_channels; i++) {
                opus_fade(s->out[i] + samples - 120 + delayed_samples,
                          s->out[i] + samples - 120 + delayed_samples,
                          s->redundancy_output[i] + 120,
                          ff_celt_window2, 120 - delayed_samples);
                if (delayed_samples)
                    s->redundancy_idx = 120 - delayed_samples;
            }
        } else {
            for (i = 0; i < s->output_channels; i++) {
                memcpy(s->out[i] + delayed_samples, s->redundancy_output[i], 120 * sizeof(float));
                opus_fade(s->out[i] + 120 + delayed_samples,
                          s->redundancy_output[i] + 120,
                          s->out[i] + 120 + delayed_samples,
                          ff_celt_window2, 120);
            }
        }
    }

    return samples;
}
Exemplo n.º 6
0
static int opus_decode_frame(OpusStreamContext *s, const uint8_t *data, int size)
{
    int samples    = s->packet.frame_duration;
    int redundancy = 0;
    int redundancy_size, redundancy_pos;
    int ret, i, consumed;
    int delayed_samples = s->delayed_samples;

    ret = ff_opus_rc_dec_init(&s->rc, data, size);
    if (ret < 0)
        return ret;

    /* decode the silk frame */
    if (s->packet.mode == OPUS_MODE_SILK || s->packet.mode == OPUS_MODE_HYBRID) {
#if CONFIG_SWRESAMPLE
        if (!swr_is_initialized(s->swr)) {
#elif CONFIG_AVRESAMPLE
        if (!avresample_is_open(s->avr)) {
#endif
            ret = opus_init_resample(s);
            if (ret < 0)
                return ret;
        }

        samples = ff_silk_decode_superframe(s->silk, &s->rc, s->silk_output,
                                            FFMIN(s->packet.bandwidth, OPUS_BANDWIDTH_WIDEBAND),
                                            s->packet.stereo + 1,
                                            silk_frame_duration_ms[s->packet.config]);
        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error decoding a SILK frame.\n");
            return samples;
        }
#if CONFIG_SWRESAMPLE
        samples = swr_convert(s->swr,
                              (uint8_t**)s->out, s->packet.frame_duration,
                              (const uint8_t**)s->silk_output, samples);
#elif CONFIG_AVRESAMPLE
        samples = avresample_convert(s->avr, (uint8_t**)s->out, s->out_size,
                                     s->packet.frame_duration,
                                     (uint8_t**)s->silk_output,
                                     sizeof(s->silk_buf[0]),
                                     samples);
#endif
        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error resampling SILK data.\n");
            return samples;
        }
        av_assert2((samples & 7) == 0);
        s->delayed_samples += s->packet.frame_duration - samples;
    } else
        ff_silk_flush(s->silk);

    // decode redundancy information
    consumed = opus_rc_tell(&s->rc);
    if (s->packet.mode == OPUS_MODE_HYBRID && consumed + 37 <= size * 8)
        redundancy = ff_opus_rc_dec_log(&s->rc, 12);
    else if (s->packet.mode == OPUS_MODE_SILK && consumed + 17 <= size * 8)
        redundancy = 1;

    if (redundancy) {
        redundancy_pos = ff_opus_rc_dec_log(&s->rc, 1);

        if (s->packet.mode == OPUS_MODE_HYBRID)
            redundancy_size = ff_opus_rc_dec_uint(&s->rc, 256) + 2;
        else
            redundancy_size = size - (consumed + 7) / 8;
        size -= redundancy_size;
        if (size < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid redundancy frame size.\n");
            return AVERROR_INVALIDDATA;
        }

        if (redundancy_pos) {
            ret = opus_decode_redundancy(s, data + size, redundancy_size);
            if (ret < 0)
                return ret;
            ff_celt_flush(s->celt);
        }
    }

    /* decode the CELT frame */
    if (s->packet.mode == OPUS_MODE_CELT || s->packet.mode == OPUS_MODE_HYBRID) {
        float *out_tmp[2] = { s->out[0], s->out[1] };
        float **dst = (s->packet.mode == OPUS_MODE_CELT) ?
                      out_tmp : s->celt_output;
        int celt_output_samples = samples;
        int delay_samples = av_audio_fifo_size(s->celt_delay);

        if (delay_samples) {
            if (s->packet.mode == OPUS_MODE_HYBRID) {
                av_audio_fifo_read(s->celt_delay, (void**)s->celt_output, delay_samples);

                for (i = 0; i < s->output_channels; i++) {
                    s->fdsp->vector_fmac_scalar(out_tmp[i], s->celt_output[i], 1.0,
                                                delay_samples);
                    out_tmp[i] += delay_samples;
                }
                celt_output_samples -= delay_samples;
            } else {
                av_log(s->avctx, AV_LOG_WARNING,
                       "Spurious CELT delay samples present.\n");
                av_audio_fifo_drain(s->celt_delay, delay_samples);
                if (s->avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_BUG;
            }
        }

        ff_opus_rc_dec_raw_init(&s->rc, data + size, size);

        ret = ff_celt_decode_frame(s->celt, &s->rc, dst,
                                   s->packet.stereo + 1,
                                   s->packet.frame_duration,
                                   (s->packet.mode == OPUS_MODE_HYBRID) ? 17 : 0,
                                   ff_celt_band_end[s->packet.bandwidth]);
        if (ret < 0)
            return ret;

        if (s->packet.mode == OPUS_MODE_HYBRID) {
            int celt_delay = s->packet.frame_duration - celt_output_samples;
            void *delaybuf[2] = { s->celt_output[0] + celt_output_samples,
                                  s->celt_output[1] + celt_output_samples };

            for (i = 0; i < s->output_channels; i++) {
                s->fdsp->vector_fmac_scalar(out_tmp[i],
                                            s->celt_output[i], 1.0,
                                            celt_output_samples);
            }

            ret = av_audio_fifo_write(s->celt_delay, delaybuf, celt_delay);
            if (ret < 0)
                return ret;
        }
    } else
        ff_celt_flush(s->celt);

    if (s->redundancy_idx) {
        for (i = 0; i < s->output_channels; i++)
            opus_fade(s->out[i], s->out[i],
                      s->redundancy_output[i] + 120 + s->redundancy_idx,
                      ff_celt_window2 + s->redundancy_idx, 120 - s->redundancy_idx);
        s->redundancy_idx = 0;
    }
    if (redundancy) {
        if (!redundancy_pos) {
            ff_celt_flush(s->celt);
            ret = opus_decode_redundancy(s, data + size, redundancy_size);
            if (ret < 0)
                return ret;

            for (i = 0; i < s->output_channels; i++) {
                opus_fade(s->out[i] + samples - 120 + delayed_samples,
                          s->out[i] + samples - 120 + delayed_samples,
                          s->redundancy_output[i] + 120,
                          ff_celt_window2, 120 - delayed_samples);
                if (delayed_samples)
                    s->redundancy_idx = 120 - delayed_samples;
            }
        } else {
            for (i = 0; i < s->output_channels; i++) {
                memcpy(s->out[i] + delayed_samples, s->redundancy_output[i], 120 * sizeof(float));
                opus_fade(s->out[i] + 120 + delayed_samples,
                          s->redundancy_output[i] + 120,
                          s->out[i] + 120 + delayed_samples,
                          ff_celt_window2, 120);
            }
        }
    }

    return samples;
}

static int opus_decode_subpacket(OpusStreamContext *s,
                                 const uint8_t *buf, int buf_size,
                                 float **out, int out_size,
                                 int nb_samples)
{
    int output_samples = 0;
    int flush_needed   = 0;
    int i, j, ret;

    s->out[0]   = out[0];
    s->out[1]   = out[1];
    s->out_size = out_size;

    /* check if we need to flush the resampler */
#if CONFIG_SWRESAMPLE
    if (swr_is_initialized(s->swr)) {
        if (buf) {
            int64_t cur_samplerate;
            av_opt_get_int(s->swr, "in_sample_rate", 0, &cur_samplerate);
            flush_needed = (s->packet.mode == OPUS_MODE_CELT) || (cur_samplerate != s->silk_samplerate);
        } else {
            flush_needed = !!s->delayed_samples;
        }
    }
#elif CONFIG_AVRESAMPLE
    if (avresample_is_open(s->avr)) {
        if (buf) {
            int64_t cur_samplerate;
            av_opt_get_int(s->avr, "in_sample_rate", 0, &cur_samplerate);
            flush_needed = (s->packet.mode == OPUS_MODE_CELT) || (cur_samplerate != s->silk_samplerate);
        } else {
            flush_needed = !!s->delayed_samples;
        }
    }
#endif

    if (!buf && !flush_needed)
        return 0;

    /* use dummy output buffers if the channel is not mapped to anything */
    if (!s->out[0] ||
        (s->output_channels == 2 && !s->out[1])) {
        av_fast_malloc(&s->out_dummy, &s->out_dummy_allocated_size, s->out_size);
        if (!s->out_dummy)
            return AVERROR(ENOMEM);
        if (!s->out[0])
            s->out[0] = s->out_dummy;
        if (!s->out[1])
            s->out[1] = s->out_dummy;
    }

    /* flush the resampler if necessary */
    if (flush_needed) {
        ret = opus_flush_resample(s, s->delayed_samples);
        if (ret < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error flushing the resampler.\n");
            return ret;
        }
#if CONFIG_SWRESAMPLE
        swr_close(s->swr);
#elif CONFIG_AVRESAMPLE
        avresample_close(s->avr);
#endif
        output_samples += s->delayed_samples;
        s->delayed_samples = 0;

        if (!buf)
            goto finish;
    }

    /* decode all the frames in the packet */
    for (i = 0; i < s->packet.frame_count; i++) {
        int size = s->packet.frame_size[i];
        int samples = opus_decode_frame(s, buf + s->packet.frame_offset[i], size);

        if (samples < 0) {
            av_log(s->avctx, AV_LOG_ERROR, "Error decoding an Opus frame.\n");
            if (s->avctx->err_recognition & AV_EF_EXPLODE)
                return samples;

            for (j = 0; j < s->output_channels; j++)
                memset(s->out[j], 0, s->packet.frame_duration * sizeof(float));
            samples = s->packet.frame_duration;
        }
        output_samples += samples;

        for (j = 0; j < s->output_channels; j++)
            s->out[j] += samples;
        s->out_size -= samples * sizeof(float);
    }

finish:
    s->out[0] = s->out[1] = NULL;
    s->out_size = 0;

    return output_samples;
}