/// <summary>
/// Resets all buffers and prepares this decoder to process a fresh (unrelated) stream
/// </summary>
public void ResetState()
{
PartialReset();
Celt_Decoder.ResetState();
DecodeAPI.silk_InitDecoder(SilkDecoder);
stream_channels = channels;
frame_size = Fs / 400;
}
/** Initializes a previously allocated decoder state.
* The state must be at least the size returned by opus_decoder_get_size().
* This is intended for applications which use their own allocator instead of malloc. @see opus_decoder_create,opus_decoder_get_size
* To reset a previously initialized state, use the #OPUS_RESET_STATE CTL.
* @param [in] st <tt>OpusDecoder*</tt>: Decoder state.
* @param [in] Fs <tt>opus_int32</tt>: Sampling rate to decode to (Hz).
* This must be one of 8000, 12000, 16000,
* 24000, or 48000.
* @param [in] channels <tt>int</tt>: Number of channels (1 or 2) to decode
* @retval #OPUS_OK Success or @ref opus_errorcodes
*/
internal int opus_decoder_init(int Fs, int channels)
{
SilkDecoder silk_dec;
CeltDecoder celt_dec;
int ret;
if ((Fs != 48000 && Fs != 24000 && Fs != 16000 && Fs != 12000 && Fs != 8000) ||
(channels != 1 && channels != 2))
{
return(OpusError.OPUS_BAD_ARG);
}
this.Reset();
/* Initialize SILK encoder */
silk_dec = this.SilkDecoder;
celt_dec = this.Celt_Decoder;
this.stream_channels = this.channels = channels;
this.Fs = Fs;
this.DecControl.API_sampleRate = this.Fs;
this.DecControl.nChannelsAPI = this.channels;
/* Reset decoder */
ret = DecodeAPI.silk_InitDecoder(silk_dec);
if (ret != 0)
{
return(OpusError.OPUS_INTERNAL_ERROR);
}
/* Initialize CELT decoder */
ret = celt_dec.celt_decoder_init(Fs, channels);
if (ret != OpusError.OPUS_OK)
{
return(OpusError.OPUS_INTERNAL_ERROR);
}
celt_dec.SetSignalling(0);
this.prev_mode = 0;
this.frame_size = Fs / 400;
return(OpusError.OPUS_OK);
}
internal int opus_decode_frame(byte[] data, int data_ptr,
int len, short[] pcm, int pcm_ptr, int frame_size, int decode_fec)
{
SilkDecoder silk_dec;
CeltDecoder celt_dec;
int i, silk_ret = 0, celt_ret = 0;
EntropyCoder dec = new EntropyCoder(); // porting note: stack var
int silk_frame_size;
int pcm_silk_size;
short[] pcm_silk;
int pcm_transition_silk_size;
short[] pcm_transition_silk;
int pcm_transition_celt_size;
short[] pcm_transition_celt;
short[] pcm_transition = null;
int redundant_audio_size;
short[] redundant_audio;
int audiosize;
OpusMode mode;
int transition = 0;
int start_band;
int redundancy = 0;
int redundancy_bytes = 0;
int celt_to_silk = 0;
int c;
int F2_5, F5, F10, F20;
int[] window;
uint redundant_rng = 0;
int celt_accum;
silk_dec = this.SilkDecoder;
celt_dec = this.Celt_Decoder;
F20 = this.Fs / 50;
F10 = F20 >> 1;
F5 = F10 >> 1;
F2_5 = F5 >> 1;
if (frame_size < F2_5)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
/* Limit frame_size to avoid excessive stack allocations. */
frame_size = Inlines.IMIN(frame_size, this.Fs / 25 * 3);
/* Payloads of 1 (2 including ToC) or 0 trigger the PLC/DTX */
if (len <= 1)
{
data = null;
/* In that case, don't conceal more than what the ToC says */
frame_size = Inlines.IMIN(frame_size, this.frame_size);
}
if (data != null)
{
audiosize = this.frame_size;
mode = this.mode;
dec.dec_init(data, data_ptr, (uint)len);
}
else
{
audiosize = frame_size;
mode = this.prev_mode;
if (mode == 0)
{
/* If we haven't got any packet yet, all we can do is return zeros */
for (i = pcm_ptr; i < pcm_ptr + (audiosize * this.channels); i++)
{
pcm[i] = 0;
}
return(audiosize);
}
/* Avoids trying to run the PLC on sizes other than 2.5 (CELT), 5 (CELT),
* 10, or 20 (e.g. 12.5 or 30 ms). */
if (audiosize > F20)
{
do
{
int ret = opus_decode_frame(null, 0, 0, pcm, pcm_ptr, Inlines.IMIN(audiosize, F20), 0);
if (ret < 0)
{
return(ret);
}
pcm_ptr += ret * this.channels;
audiosize -= ret;
} while (audiosize > 0);
return(frame_size);
}
else if (audiosize < F20)
{
if (audiosize > F10)
{
audiosize = F10;
}
else if (mode != OpusMode.MODE_SILK_ONLY && audiosize > F5 && audiosize < F10)
{
audiosize = F5;
}
}
}
/* In fixed-point, we can tell CELT to do the accumulation on top of the
* SILK PCM buffer. This saves some stack space. */
celt_accum = ((mode != OpusMode.MODE_CELT_ONLY) && (frame_size >= F10)) ? 1 : 0;
pcm_transition_silk_size = 0;
pcm_transition_celt_size = 0;
if (data != null && this.prev_mode > 0 && (
(mode == OpusMode.MODE_CELT_ONLY && this.prev_mode != OpusMode.MODE_CELT_ONLY && (this.prev_redundancy == 0)) ||
(mode != OpusMode.MODE_CELT_ONLY && this.prev_mode == OpusMode.MODE_CELT_ONLY))
)
{
transition = 1;
/* Decide where to allocate the stack memory for pcm_transition */
if (mode == OpusMode.MODE_CELT_ONLY)
{
pcm_transition_celt_size = F5 * this.channels;
}
else
{
pcm_transition_silk_size = F5 * this.channels;
}
}
pcm_transition_celt = new short[pcm_transition_celt_size];
if (transition != 0 && mode == OpusMode.MODE_CELT_ONLY)
{
pcm_transition = pcm_transition_celt;
opus_decode_frame(null, 0, 0, pcm_transition, 0, Inlines.IMIN(F5, audiosize), 0);
}
if (audiosize > frame_size)
{
/*fprintf(stderr, "PCM buffer too small: %d vs %d (mode = %d)\n", audiosize, frame_size, mode);*/
return(OpusError.OPUS_BAD_ARG);
}
else
{
frame_size = audiosize;
}
/* Don't allocate any memory when in CELT-only mode */
pcm_silk_size = (mode != OpusMode.MODE_CELT_ONLY && (celt_accum == 0)) ? Inlines.IMAX(F10, frame_size) * this.channels : 0;
pcm_silk = new short[pcm_silk_size];
/* SILK processing */
if (mode != OpusMode.MODE_CELT_ONLY)
{
int lost_flag, decoded_samples;
short[] pcm_ptr2;
int pcm_ptr2_ptr = 0;
if (celt_accum != 0)
{
pcm_ptr2 = pcm;
pcm_ptr2_ptr = pcm_ptr;
}
else
{
pcm_ptr2 = pcm_silk;
pcm_ptr2_ptr = 0;
}
if (this.prev_mode == OpusMode.MODE_CELT_ONLY)
{
DecodeAPI.silk_InitDecoder(silk_dec);
}
/* The SILK PLC cannot produce frames of less than 10 ms */
this.DecControl.payloadSize_ms = Inlines.IMAX(10, 1000 * audiosize / this.Fs);
if (data != null)
{
this.DecControl.nChannelsInternal = this.stream_channels;
if (mode == OpusMode.MODE_SILK_ONLY)
{
if (this.bandwidth == OpusBandwidth.OPUS_BANDWIDTH_NARROWBAND)
{
this.DecControl.internalSampleRate = 8000;
}
else if (this.bandwidth == OpusBandwidth.OPUS_BANDWIDTH_MEDIUMBAND)
{
this.DecControl.internalSampleRate = 12000;
}
else if (this.bandwidth == OpusBandwidth.OPUS_BANDWIDTH_WIDEBAND)
{
this.DecControl.internalSampleRate = 16000;
}
else
{
this.DecControl.internalSampleRate = 16000;
Inlines.OpusAssert(false);
}
}
else
{
/* Hybrid mode */
this.DecControl.internalSampleRate = 16000;
}
}
lost_flag = data == null ? 1 : 2 * decode_fec;
decoded_samples = 0;
do
{
/* Call SILK decoder */
int first_frame = (decoded_samples == 0) ? 1 : 0;
silk_ret = DecodeAPI.silk_Decode(silk_dec, this.DecControl,
lost_flag, first_frame, dec, pcm_ptr2, pcm_ptr2_ptr, out silk_frame_size);
if (silk_ret != 0)
{
if (lost_flag != 0)
{
/* PLC failure should not be fatal */
silk_frame_size = frame_size;
Arrays.MemSetWithOffset <short>(pcm_ptr2, 0, pcm_ptr2_ptr, frame_size * this.channels);
}
else
{
return(OpusError.OPUS_INTERNAL_ERROR);
}
}
pcm_ptr2_ptr += (silk_frame_size * this.channels);
decoded_samples += silk_frame_size;
} while (decoded_samples < frame_size);
}
start_band = 0;
if (decode_fec == 0 && mode != OpusMode.MODE_CELT_ONLY && data != null &&
dec.tell() + 17 + 20 * (this.mode == OpusMode.MODE_HYBRID ? 1 : 0) <= 8 * len)
{
/* Check if we have a redundant 0-8 kHz band */
if (mode == OpusMode.MODE_HYBRID)
{
redundancy = dec.dec_bit_logp(12);
}
else
{
redundancy = 1;
}
if (redundancy != 0)
{
celt_to_silk = dec.dec_bit_logp(1);
/* redundancy_bytes will be at least two, in the non-hybrid
* case due to the ec_tell() check above */
redundancy_bytes = mode == OpusMode.MODE_HYBRID ?
(int)dec.dec_uint(256) + 2 :
len - ((dec.tell() + 7) >> 3);
len -= redundancy_bytes;
/* This is a sanity check. It should never happen for a valid
* packet, so the exact behaviour is not normative. */
if (len * 8 < dec.tell())
{
len = 0;
redundancy_bytes = 0;
redundancy = 0;
}
/* Shrink decoder because of raw bits */
dec.storage = (uint)(dec.storage - redundancy_bytes);
}
}
if (mode != OpusMode.MODE_CELT_ONLY)
{
start_band = 17;
}
{
int endband = 21;
switch (this.bandwidth)
{
case OpusBandwidth.OPUS_BANDWIDTH_NARROWBAND:
endband = 13;
break;
case OpusBandwidth.OPUS_BANDWIDTH_MEDIUMBAND:
case OpusBandwidth.OPUS_BANDWIDTH_WIDEBAND:
endband = 17;
break;
case OpusBandwidth.OPUS_BANDWIDTH_SUPERWIDEBAND:
endband = 19;
break;
case OpusBandwidth.OPUS_BANDWIDTH_FULLBAND:
endband = 21;
break;
}
celt_dec.SetEndBand(endband);
celt_dec.SetChannels(this.stream_channels);
}
if (redundancy != 0)
{
transition = 0;
pcm_transition_silk_size = 0;
}
pcm_transition_silk = new short[pcm_transition_silk_size];
if (transition != 0 && mode != OpusMode.MODE_CELT_ONLY)
{
pcm_transition = pcm_transition_silk;
opus_decode_frame(null, 0, 0, pcm_transition, 0, Inlines.IMIN(F5, audiosize), 0);
}
/* Only allocation memory for redundancy if/when needed */
redundant_audio_size = redundancy != 0 ? F5 * this.channels : 0;
redundant_audio = new short[redundant_audio_size];
/* 5 ms redundant frame for CELT->SILK*/
if (redundancy != 0 && celt_to_silk != 0)
{
celt_dec.SetStartBand(0);
celt_dec.celt_decode_with_ec(data, (data_ptr + len), redundancy_bytes,
redundant_audio, 0, F5, null, 0);
redundant_rng = celt_dec.GetFinalRange();
}
/* MUST be after PLC */
celt_dec.SetStartBand(start_band);
if (mode != OpusMode.MODE_SILK_ONLY)
{
int celt_frame_size = Inlines.IMIN(F20, frame_size);
/* Make sure to discard any previous CELT state */
if (mode != this.prev_mode && this.prev_mode > 0 && this.prev_redundancy == 0)
{
celt_dec.ResetState();
}
/* Decode CELT */
celt_ret = celt_dec.celt_decode_with_ec(decode_fec != 0 ? null : data, data_ptr,
len, pcm, pcm_ptr, celt_frame_size, dec, celt_accum);
}
else
{
if (celt_accum == 0)
{
for (i = pcm_ptr; i < (frame_size * this.channels) + pcm_ptr; i++)
{
pcm[i] = 0;
}
}
/* For hybrid -> SILK transitions, we let the CELT MDCT
* do a fade-out by decoding a silence frame */
if (this.prev_mode == OpusMode.MODE_HYBRID && !(redundancy != 0 && celt_to_silk != 0 && this.prev_redundancy != 0))
{
celt_dec.SetStartBand(0);
celt_dec.celt_decode_with_ec(SILENCE, 0, 2, pcm, pcm_ptr, F2_5, null, celt_accum);
}
}
if (mode != OpusMode.MODE_CELT_ONLY && celt_accum == 0)
{
for (i = 0; i < frame_size * this.channels; i++)
{
pcm[pcm_ptr + i] = Inlines.SAT16(Inlines.ADD32(pcm[pcm_ptr + i], pcm_silk[i]));
}
}
window = celt_dec.GetMode().window;
/* 5 ms redundant frame for SILK->CELT */
if (redundancy != 0 && celt_to_silk == 0)
{
celt_dec.ResetState();
celt_dec.SetStartBand(0);
celt_dec.celt_decode_with_ec(data, data_ptr + len, redundancy_bytes, redundant_audio, 0, F5, null, 0);
redundant_rng = celt_dec.GetFinalRange();
CodecHelpers.smooth_fade(pcm, pcm_ptr + this.channels * (frame_size - F2_5), redundant_audio, this.channels * F2_5,
pcm, (pcm_ptr + this.channels * (frame_size - F2_5)), F2_5, this.channels, window, this.Fs);
}
if (redundancy != 0 && celt_to_silk != 0)
{
for (c = 0; c < this.channels; c++)
{
for (i = 0; i < F2_5; i++)
{
pcm[this.channels * i + c + pcm_ptr] = redundant_audio[this.channels * i + c];
}
}
CodecHelpers.smooth_fade(redundant_audio, (this.channels * F2_5), pcm, (pcm_ptr + (this.channels * F2_5)),
pcm, (pcm_ptr + (this.channels * F2_5)), F2_5, this.channels, window, this.Fs);
}
if (transition != 0)
{
if (audiosize >= F5)
{
for (i = 0; i < this.channels * F2_5; i++)
{
pcm[i] = pcm_transition[i];
}
CodecHelpers.smooth_fade(pcm_transition, (this.channels * F2_5), pcm, (pcm_ptr + (this.channels * F2_5)),
pcm, (pcm_ptr + (this.channels * F2_5)), F2_5,
this.channels, window, this.Fs);
}
else
{
/* Not enough time to do a clean transition, but we do it anyway
* This will not preserve amplitude perfectly and may introduce
* a bit of temporal aliasing, but it shouldn't be too bad and
* that's pretty much the best we can do. In any case, generating this
* transition is pretty silly in the first place */
CodecHelpers.smooth_fade(pcm_transition, 0, pcm, pcm_ptr,
pcm, pcm_ptr, F2_5,
this.channels, window, this.Fs);
}
}
if (this.decode_gain != 0)
{
int gain;
gain = Inlines.celt_exp2(Inlines.MULT16_16_P15(((short)(0.5 + (6.48814081e-4f) * (((int)1) << (25)))) /*Inlines.QCONST16(6.48814081e-4f, 25)*/, this.decode_gain));
for (i = pcm_ptr; i < pcm_ptr + (frame_size * this.channels); i++)
{
int x;
x = Inlines.MULT16_32_P16(pcm[i], gain);
pcm[i] = (short)Inlines.SATURATE(x, 32767);
}
}
if (len <= 1)
{
this.rangeFinal = 0;
}
else
{
this.rangeFinal = dec.rng ^ redundant_rng;
}
this.prev_mode = mode;
this.prev_redundancy = (redundancy != 0 && celt_to_silk == 0) ? 1 : 0;
return(celt_ret < 0 ? celt_ret : audiosize);
}