/// <summary>
/// Decodes an Opus packet, putting the output data into a floating-point buffer.
/// </summary>
/// <param name="in_data">The input payload. This may be NULL if that previous packet was lost in transit (when PLC is enabled)</param>
/// <param name="in_data_offset">The offset to use when reading the input payload. Usually 0</param>
/// <param name="len">The number of bytes in the payload</param>
/// <param name="out_pcm">A buffer to put the output PCM. The output size is (# of samples) * (# of channels).
/// You can use the OpusPacketInfo helpers to get a hint of the frame size before you decode the packet if you need
/// exact sizing. Otherwise, the minimum safe buffer size is 5760 samples</param>
/// <param name="out_pcm_offset">The offset to use when writing to the output buffer</param>
/// <param name="frame_size">The number of samples (per channel) of available space in the output PCM buf.
/// If this is less than the maximum packet duration (120ms; 5760 for 48khz), this function will
/// not be capable of decoding some packets. In the case of PLC (data == NULL) or FEC (decode_fec == true),
/// then frame_size needs to be exactly the duration of the audio that is missing, otherwise the decoder will
/// not be in an optimal state to decode the next incoming packet. For the PLC and FEC cases, frame_size *must*
/// be a multiple of 10 ms.</param>
/// <param name="decode_fec">Indicates that we want to recreate the PREVIOUS (lost) packet using FEC data from THIS packet. Using this packet
/// recovery scheme, you will actually decode this packet twice, first with decode_fec TRUE and then again with FALSE. If FEC data is not
/// available in this packet, the decoder will simply generate a best-effort recreation of the lost packet. In that case,
/// the length of frame_size must be EXACTLY the length of the audio that was lost, or else the decoder will be in an inconsistent state.</param>
/// <returns>The number of decoded samples (per channel)</returns>
public int Decode(byte[] in_data, int in_data_offset,
int len, float[] out_pcm, int out_pcm_offset, int frame_size, bool decode_fec = false)
{
short[] output;
int ret, i;
int nb_samples;
if (frame_size <= 0)
{
throw new ArgumentException("Frame size must be > 0");
}
if (in_data != null && len > 0 && !decode_fec)
{
nb_samples = OpusPacketInfo.GetNumSamples(this, in_data, in_data_offset, len);
if (nb_samples > 0)
{
frame_size = Inlines.IMIN(frame_size, nb_samples);
}
else
{
throw new OpusException("An invalid packet was provided (unable to parse # of samples)");
}
}
output = new short[frame_size * this.channels];
try
{
int dummy;
ret = opus_decode_native(in_data, in_data_offset, len, output, 0, frame_size, decode_fec ? 1 : 0, 0, out dummy, 0);
if (ret < 0)
{
// An error happened; report it
if (ret == OpusError.OPUS_BAD_ARG)
{
throw new ArgumentException("OPUS_BAD_ARG when decoding");
}
throw new OpusException("An error occurred during decoding", ret);
}
if (ret > 0)
{
for (i = 0; i < ret * this.channels; i++)
{
out_pcm[out_pcm_offset + i] = (1.0f / 32768.0f) * (output[i]);
}
}
return(ret);
}
catch (ArgumentException e)
{
throw new OpusException("Internal error during decoding: " + e.Message);
}
}
// FIXME THIS METHOD FAILS IN TEST_OPUS_ENCODE
/** Remove all padding from a given Opus multi-stream packet and rewrite the TOC sequence to
* minimize space usage.
* @param[in,out] data <tt>const unsigned char*</tt>: The buffer containing the
* packet to strip.
* @param len <tt>opus_int32</tt>: The size of the packet.
* This must be at least 1.
* @param nb_streams <tt>opus_int32</tt>: The number of streams (not channels) in the packet.
* This must be at least 1.
* @returns The new size of the output packet on success, or an error code
* on failure.
* @retval #OPUS_BAD_ARG \a len was less than 1 or new_len was less than len.
* @retval #OPUS_INVALID_PACKET \a data did not contain a valid Opus packet.
*/
public static int UnpadMultistreamPacket(byte[] data, int data_offset, int len, int nb_streams)
{
int s;
byte dummy_toc;
short[] size = new short[48];
int packet_offset;
int dummy_offset;
OpusRepacketizer rp = new OpusRepacketizer();
int dst;
int dst_len;
if (len < 1)
{
return(OpusError.OPUS_BAD_ARG);
}
dst = data_offset;
dst_len = 0;
/* Unpad all frames */
for (s = 0; s < nb_streams; s++)
{
int ret;
int self_delimited = ((s != nb_streams) ? 1 : 0) - 1;
if (len <= 0)
{
return(OpusError.OPUS_INVALID_PACKET);
}
rp.Reset();
ret = OpusPacketInfo.opus_packet_parse_impl(data, data_offset, len, self_delimited, out dummy_toc, null, null, 0,
size, 0, out dummy_offset, out packet_offset);
if (ret < 0)
{
return(ret);
}
ret = rp.opus_repacketizer_cat_impl(data, data_offset, packet_offset, self_delimited);
if (ret < 0)
{
return(ret);
}
ret = rp.opus_repacketizer_out_range_impl(0, rp.nb_frames, data, dst, len, self_delimited, 0);
if (ret < 0)
{
return(ret);
}
else
{
dst_len += ret;
}
dst += ret;
data_offset += packet_offset;
len -= packet_offset;
}
return(dst_len);
}
internal int opus_repacketizer_cat_impl(byte[] data, int data_ptr, int len, int self_delimited)
{
byte dummy_toc;
int dummy_offset;
int curr_nb_frames, ret;
/* Set of check ToC */
if (len < 1)
{
return(OpusError.OPUS_INVALID_PACKET);
}
if (this.nb_frames == 0)
{
this.toc = data[data_ptr];
this.framesize = OpusPacketInfo.GetNumSamplesPerFrame(data, data_ptr, 8000);
}
else if ((this.toc & 0xFC) != (data[data_ptr] & 0xFC))
{
/*fprintf(stderr, "toc mismatch: 0x%x vs 0x%x\n", rp.toc, data[0]);*/
return(OpusError.OPUS_INVALID_PACKET);
}
curr_nb_frames = OpusPacketInfo.GetNumFrames(data, data_ptr, len);
if (curr_nb_frames < 1)
{
return(OpusError.OPUS_INVALID_PACKET);
}
/* Check the 120 ms maximum packet size */
if ((curr_nb_frames + this.nb_frames) * this.framesize > 960)
{
return(OpusError.OPUS_INVALID_PACKET);
}
ret = OpusPacketInfo.opus_packet_parse_impl(data, data_ptr, len, self_delimited, out dummy_toc, this.frames, this.frames_ptrs, this.nb_frames, this.len, this.nb_frames, out dummy_offset, out dummy_offset);
if (ret < 1)
{
return(ret);
}
this.nb_frames += curr_nb_frames;
return(OpusError.OPUS_OK);
}
/** Pads a given Opus multi-stream packet to a larger size (possibly changing the TOC sequence).
* @param[in,out] data <tt>const unsigned char*</tt>: The buffer containing the
* packet to pad.
* @param len <tt>opus_int32</tt>: The size of the packet.
* This must be at least 1.
* @param new_len <tt>opus_int32</tt>: The desired size of the packet after padding.
* This must be at least 1.
* @param nb_streams <tt>opus_int32</tt>: The number of streams (not channels) in the packet.
* This must be at least as large as len.
* @returns an error code
* @retval #OPUS_OK \a on success.
* @retval #OPUS_BAD_ARG \a len was less than 1.
* @retval #OPUS_INVALID_PACKET \a data did not contain a valid Opus packet.
*/
public static int PadMultistreamPacket(byte[] data, int data_offset, int len, int new_len, int nb_streams)
{
int s;
int count;
byte dummy_toc;
short[] size = new short[48];
int packet_offset;
int dummy_offset;
int amount;
if (len < 1)
{
return(OpusError.OPUS_BAD_ARG);
}
if (len == new_len)
{
return(OpusError.OPUS_OK);
}
else if (len > new_len)
{
return(OpusError.OPUS_BAD_ARG);
}
amount = new_len - len;
/* Seek to last stream */
for (s = 0; s < nb_streams - 1; s++)
{
if (len <= 0)
{
return(OpusError.OPUS_INVALID_PACKET);
}
count = OpusPacketInfo.opus_packet_parse_impl(data, data_offset, len, 1, out dummy_toc, null, null, 0,
size, 0, out dummy_offset, out packet_offset);
if (count < 0)
{
return(count);
}
data_offset += packet_offset;
len -= packet_offset;
}
return(PadPacket(data, data_offset, len, len + amount));
}
internal static int opus_multistream_packet_validate(byte[] data, int data_ptr,
int len, int nb_streams, int Fs)
{
int s;
int count;
byte toc;
short[] size = new short[48];
int samples = 0;
int packet_offset;
int dummy;
for (s = 0; s < nb_streams; s++)
{
int tmp_samples;
if (len <= 0)
{
return(OpusError.OPUS_INVALID_PACKET);
}
count = OpusPacketInfo.opus_packet_parse_impl(data, data_ptr, len, (s != nb_streams - 1) ? 1 : 0, out toc, null, null, 0,
size, 0, out dummy, out packet_offset);
if (count < 0)
{
return(count);
}
tmp_samples = OpusPacketInfo.GetNumSamples(data, data_ptr, packet_offset, Fs);
if (s != 0 && samples != tmp_samples)
{
return(OpusError.OPUS_INVALID_PACKET);
}
samples = tmp_samples;
data_ptr += packet_offset;
len -= packet_offset;
}
return(samples);
}
internal int opus_repacketizer_out_range_impl(int begin, int end,
byte[] data, int data_ptr, int maxlen, int self_delimited, int pad)
{
int i, count;
int tot_size;
int ptr;
if (begin < 0 || begin >= end || end > this.nb_frames)
{
/*fprintf(stderr, "%d %d %d\n", begin, end, rp.nb_frames);*/
return(OpusError.OPUS_BAD_ARG);
}
count = end - begin;
if (self_delimited != 0)
{
tot_size = 1 + (this.len[count - 1] >= 252 ? 1 : 0);
}
else
{
tot_size = 0;
}
ptr = data_ptr;
if (count == 1)
{
/* Code 0 */
tot_size += this.len[0] + 1;
if (tot_size > maxlen)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
data[ptr++] = (byte)(this.toc & 0xFC);
}
else if (count == 2)
{
if (this.len[1] == this.len[0])
{
/* Code 1 */
tot_size += 2 * this.len[0] + 1;
if (tot_size > maxlen)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
data[ptr++] = (byte)((this.toc & 0xFC) | 0x1);
}
else
{
/* Code 2 */
tot_size += this.len[0] + this.len[1] + 2 + (this.len[0] >= 252 ? 1 : 0);
if (tot_size > maxlen)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
data[ptr++] = (byte)((this.toc & 0xFC) | 0x2);
ptr += OpusPacketInfo.encode_size(this.len[0], data, ptr);
}
}
if (count > 2 || (pad != 0 && tot_size < maxlen))
{
/* Code 3 */
int vbr;
int pad_amount = 0;
/* Restart the process for the padding case */
ptr = data_ptr;
if (self_delimited != 0)
{
tot_size = 1 + (this.len[count - 1] >= 252 ? 1 : 0);
}
else
{
tot_size = 0;
}
vbr = 0;
for (i = 1; i < count; i++)
{
if (this.len[i] != this.len[0])
{
vbr = 1;
break;
}
}
if (vbr != 0)
{
tot_size += 2;
for (i = 0; i < count - 1; i++)
{
tot_size += 1 + (this.len[i] >= 252 ? 1 : 0) + this.len[i];
}
tot_size += this.len[count - 1];
if (tot_size > maxlen)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
data[ptr++] = (byte)((this.toc & 0xFC) | 0x3);
data[ptr++] = (byte)(count | 0x80);
}
else
{
tot_size += count * this.len[0] + 2;
if (tot_size > maxlen)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
data[ptr++] = (byte)((this.toc & 0xFC) | 0x3);
data[ptr++] = (byte)(count);
}
pad_amount = pad != 0 ? (maxlen - tot_size) : 0;
if (pad_amount != 0)
{
int nb_255s;
data[data_ptr + 1] |= 0x40;
nb_255s = (pad_amount - 1) / 255;
for (i = 0; i < nb_255s; i++)
{
data[ptr++] = 255;
}
data[ptr++] = (byte)(pad_amount - 255 * nb_255s - 1);
tot_size += pad_amount;
}
if (vbr != 0)
{
for (i = 0; i < count - 1; i++)
{
ptr += (OpusPacketInfo.encode_size(this.len[i], data, ptr));
}
}
}
if (self_delimited != 0)
{
int sdlen = OpusPacketInfo.encode_size(this.len[count - 1], data, ptr);
ptr += (sdlen);
}
/* Copy the actual data */
for (i = begin; i < count + begin; i++)
{
if (this.frames[i] == data)
{
/* Using OPUS_MOVE() instead of OPUS_COPY() in case we're doing in-place
* padding from opus_packet_pad or opus_packet_unpad(). */
Arrays.MemMove <byte>(data, frames_ptrs[i], ptr, this.len[i]);
}
else
{
Array.Copy(this.frames[i], frames_ptrs[i], data, ptr, this.len[i]);
}
ptr += this.len[i];
}
if (pad != 0)
{
/* Fill padding with zeros. */
//Arrays.MemSetWithOffset<byte>(ptr.Data, 0, ptr.Offset, data.Offset + maxlen - ptr.Offset);
// FIXME why did they not just use a MemSet(0) here?
while (ptr < data_ptr + maxlen)
{
data[ptr++] = 0;
}
}
return(tot_size);
}
internal int opus_decode_native(byte[] data, int data_ptr,
int len, short[] pcm_out, int pcm_out_ptr, int frame_size, int decode_fec,
int self_delimited, out int packet_offset, int soft_clip)
{
int i, nb_samples;
int count, offset;
byte toc;
int packet_frame_size, packet_stream_channels;
packet_offset = 0;
OpusBandwidth packet_bandwidth;
OpusMode packet_mode;
/* 48 x 2.5 ms = 120 ms */
// fixme: make sure these values can fit in an int16
short[] size = new short[48];
if (decode_fec < 0 || decode_fec > 1)
{
return(OpusError.OPUS_BAD_ARG);
}
/* For FEC/PLC, frame_size has to be to have a multiple of 2.5 ms */
if ((decode_fec != 0 || len == 0 || data == null) && frame_size % (this.Fs / 400) != 0)
{
return(OpusError.OPUS_BAD_ARG);
}
if (len == 0 || data == null)
{
int pcm_count = 0;
do
{
int ret;
ret = opus_decode_frame(null, 0, 0, pcm_out, pcm_out_ptr + (pcm_count * this.channels), frame_size - pcm_count, 0);
if (ret < 0)
{
return(ret);
}
pcm_count += ret;
} while (pcm_count < frame_size);
Inlines.OpusAssert(pcm_count == frame_size);
this.last_packet_duration = pcm_count;
return(pcm_count);
}
else if (len < 0)
{
return(OpusError.OPUS_BAD_ARG);
}
packet_mode = OpusPacketInfo.GetEncoderMode(data, data_ptr);
packet_bandwidth = OpusPacketInfo.GetBandwidth(data, data_ptr);
packet_frame_size = OpusPacketInfo.GetNumSamplesPerFrame(data, data_ptr, this.Fs);
packet_stream_channels = OpusPacketInfo.GetNumEncodedChannels(data, data_ptr);
count = OpusPacketInfo.opus_packet_parse_impl(data, data_ptr, len, self_delimited, out toc, null, null, 0,
size, 0, out offset, out packet_offset);
if (count < 0)
{
return(count);
}
data_ptr += offset;
if (decode_fec != 0)
{
int dummy;
int duration_copy;
int ret;
/* If no FEC can be present, run the PLC (recursive call) */
if (frame_size < packet_frame_size || packet_mode == OpusMode.MODE_CELT_ONLY || this.mode == OpusMode.MODE_CELT_ONLY)
{
return(opus_decode_native(null, 0, 0, pcm_out, pcm_out_ptr, frame_size, 0, 0, out dummy, soft_clip));
}
/* Otherwise, run the PLC on everything except the size for which we might have FEC */
duration_copy = this.last_packet_duration;
if (frame_size - packet_frame_size != 0)
{
ret = opus_decode_native(null, 0, 0, pcm_out, pcm_out_ptr, frame_size - packet_frame_size, 0, 0, out dummy, soft_clip);
if (ret < 0)
{
this.last_packet_duration = duration_copy;
return(ret);
}
Inlines.OpusAssert(ret == frame_size - packet_frame_size);
}
/* Complete with FEC */
this.mode = packet_mode;
this.bandwidth = packet_bandwidth;
this.frame_size = packet_frame_size;
this.stream_channels = packet_stream_channels;
ret = opus_decode_frame(data, data_ptr, size[0], pcm_out, pcm_out_ptr + (this.channels * (frame_size - packet_frame_size)),
packet_frame_size, 1);
if (ret < 0)
{
return(ret);
}
else
{
this.last_packet_duration = frame_size;
return(frame_size);
}
}
if (count * packet_frame_size > frame_size)
{
return(OpusError.OPUS_BUFFER_TOO_SMALL);
}
/* Update the state as the last step to avoid updating it on an invalid packet */
this.mode = packet_mode;
this.bandwidth = packet_bandwidth;
this.frame_size = packet_frame_size;
this.stream_channels = packet_stream_channels;
nb_samples = 0;
for (i = 0; i < count; i++)
{
int ret;
ret = opus_decode_frame(data, data_ptr, size[i], pcm_out, pcm_out_ptr + (nb_samples * this.channels), frame_size - nb_samples, 0);
if (ret < 0)
{
return(ret);
}
Inlines.OpusAssert(ret == packet_frame_size);
data_ptr += size[i];
nb_samples += ret;
}
this.last_packet_duration = nb_samples;
return(nb_samples);
}
