/// <summary>
/// Encode quantization indices of excitation
/// </summary>
/// <param name="psRangeEnc">I/O compressor data structure</param>
/// <param name="signalType">I Signal type</param>
/// <param name="quantOffsetType">I quantOffsetType</param>
/// <param name="pulses">I quantization indices</param>
/// <param name="frame_length">I Frame length</param>
internal static void silk_encode_pulses(
EntropyCoder psRangeEnc,
int signalType,
int quantOffsetType,
sbyte[] pulses,
int frame_length)
{
int i, k, j, iter, bit, nLS, scale_down, RateLevelIndex = 0;
int abs_q, minSumBits_Q5, sumBits_Q5;
int[] abs_pulses;
int[] sum_pulses;
int[] nRshifts;
int[] pulses_comb = new int[8];
int abs_pulses_ptr;
int pulses_ptr;
byte[] nBits_ptr;
Arrays.MemSetInt(pulses_comb, 0, 8);
/****************************/
/* Prepare for shell coding */
/****************************/
/* Calculate number of shell blocks */
Inlines.OpusAssert(1 << SilkConstants.LOG2_SHELL_CODEC_FRAME_LENGTH == SilkConstants.SHELL_CODEC_FRAME_LENGTH);
iter = Inlines.silk_RSHIFT(frame_length, SilkConstants.LOG2_SHELL_CODEC_FRAME_LENGTH);
if (iter * SilkConstants.SHELL_CODEC_FRAME_LENGTH < frame_length)
{
Inlines.OpusAssert(frame_length == 12 * 10); /* Make sure only happens for 10 ms @ 12 kHz */
iter++;
Arrays.MemSetWithOffset <sbyte>(pulses, 0, frame_length, SilkConstants.SHELL_CODEC_FRAME_LENGTH);
}
/* Take the absolute value of the pulses */
abs_pulses = new int[iter * SilkConstants.SHELL_CODEC_FRAME_LENGTH];
Inlines.OpusAssert((SilkConstants.SHELL_CODEC_FRAME_LENGTH & 3) == 0);
// unrolled loop
for (i = 0; i < iter * SilkConstants.SHELL_CODEC_FRAME_LENGTH; i += 4)
{
abs_pulses[i + 0] = (int)Inlines.silk_abs(pulses[i + 0]);
abs_pulses[i + 1] = (int)Inlines.silk_abs(pulses[i + 1]);
abs_pulses[i + 2] = (int)Inlines.silk_abs(pulses[i + 2]);
abs_pulses[i + 3] = (int)Inlines.silk_abs(pulses[i + 3]);
}
/* Calc sum pulses per shell code frame */
sum_pulses = new int[iter];
nRshifts = new int[iter];
abs_pulses_ptr = 0;
for (i = 0; i < iter; i++)
{
nRshifts[i] = 0;
while (true)
{
/* 1+1 . 2 */
scale_down = combine_and_check(pulses_comb, 0, abs_pulses, abs_pulses_ptr, Tables.silk_max_pulses_table[0], 8);
/* 2+2 . 4 */
scale_down += combine_and_check(pulses_comb, pulses_comb, Tables.silk_max_pulses_table[1], 4);
/* 4+4 . 8 */
scale_down += combine_and_check(pulses_comb, pulses_comb, Tables.silk_max_pulses_table[2], 2);
/* 8+8 . 16 */
scale_down += combine_and_check(sum_pulses, i, pulses_comb, 0, Tables.silk_max_pulses_table[3], 1);
if (scale_down != 0)
{
/* We need to downscale the quantization signal */
nRshifts[i]++;
for (k = abs_pulses_ptr; k < abs_pulses_ptr + SilkConstants.SHELL_CODEC_FRAME_LENGTH; k++)
{
abs_pulses[k] = Inlines.silk_RSHIFT(abs_pulses[k], 1);
}
}
else
{
/* Jump out of while(1) loop and go to next shell coding frame */
break;
}
}
abs_pulses_ptr += SilkConstants.SHELL_CODEC_FRAME_LENGTH;
}
/**************/
/* Rate level */
/**************/
/* find rate level that leads to fewest bits for coding of pulses per block info */
minSumBits_Q5 = int.MaxValue;
for (k = 0; k < SilkConstants.N_RATE_LEVELS - 1; k++)
{
nBits_ptr = Tables.silk_pulses_per_block_BITS_Q5[k];
sumBits_Q5 = Tables.silk_rate_levels_BITS_Q5[signalType >> 1][k];
for (i = 0; i < iter; i++)
{
if (nRshifts[i] > 0)
{
sumBits_Q5 += nBits_ptr[SilkConstants.SILK_MAX_PULSES + 1];
}
else
{
sumBits_Q5 += nBits_ptr[sum_pulses[i]];
}
}
if (sumBits_Q5 < minSumBits_Q5)
{
minSumBits_Q5 = sumBits_Q5;
RateLevelIndex = k;
}
}
psRangeEnc.enc_icdf(RateLevelIndex, Tables.silk_rate_levels_iCDF[signalType >> 1], 8);
/***************************************************/
/* Sum-Weighted-Pulses Encoding */
/***************************************************/
for (i = 0; i < iter; i++)
{
if (nRshifts[i] == 0)
{
psRangeEnc.enc_icdf(sum_pulses[i], Tables.silk_pulses_per_block_iCDF[RateLevelIndex], 8);
}
else
{
psRangeEnc.enc_icdf(SilkConstants.SILK_MAX_PULSES + 1, Tables.silk_pulses_per_block_iCDF[RateLevelIndex], 8);
for (k = 0; k < nRshifts[i] - 1; k++)
{
psRangeEnc.enc_icdf(SilkConstants.SILK_MAX_PULSES + 1, Tables.silk_pulses_per_block_iCDF[SilkConstants.N_RATE_LEVELS - 1], 8);
}
psRangeEnc.enc_icdf(sum_pulses[i], Tables.silk_pulses_per_block_iCDF[SilkConstants.N_RATE_LEVELS - 1], 8);
}
}
/******************/
/* Shell Encoding */
/******************/
for (i = 0; i < iter; i++)
{
if (sum_pulses[i] > 0)
{
ShellCoder.silk_shell_encoder(psRangeEnc, abs_pulses, i * SilkConstants.SHELL_CODEC_FRAME_LENGTH);
}
}
/****************/
/* LSB Encoding */
/****************/
for (i = 0; i < iter; i++)
{
if (nRshifts[i] > 0)
{
pulses_ptr = i * SilkConstants.SHELL_CODEC_FRAME_LENGTH;
nLS = nRshifts[i] - 1;
for (k = 0; k < SilkConstants.SHELL_CODEC_FRAME_LENGTH; k++)
{
abs_q = (sbyte)Inlines.silk_abs(pulses[pulses_ptr + k]);
for (j = nLS; j > 0; j--)
{
bit = Inlines.silk_RSHIFT(abs_q, j) & 1;
psRangeEnc.enc_icdf(bit, Tables.silk_lsb_iCDF, 8);
}
bit = abs_q & 1;
psRangeEnc.enc_icdf(bit, Tables.silk_lsb_iCDF, 8);
}
}
}
/****************/
/* Encode signs */
/****************/
CodeSigns.silk_encode_signs(psRangeEnc, pulses, frame_length, signalType, quantOffsetType, sum_pulses);
}
/*********************************************/
/* Decode quantization indices of excitation */
/*********************************************/
internal static void silk_decode_pulses(
EntropyCoder psRangeDec, /* I/O Compressor data structure */
short[] pulses, /* O Excitation signal */
int signalType, /* I Sigtype */
int quantOffsetType, /* I quantOffsetType */
int frame_length /* I Frame length */
)
{
int i, j, k, iter, abs_q, nLS, RateLevelIndex;
int[] sum_pulses = new int[SilkConstants.MAX_NB_SHELL_BLOCKS];
int[] nLshifts = new int[SilkConstants.MAX_NB_SHELL_BLOCKS];
int pulses_ptr;
/*********************/
/* Decode rate level */
/*********************/
RateLevelIndex = psRangeDec.dec_icdf(Tables.silk_rate_levels_iCDF[signalType >> 1], 8);
/* Calculate number of shell blocks */
Inlines.OpusAssert(1 << SilkConstants.LOG2_SHELL_CODEC_FRAME_LENGTH == SilkConstants.SHELL_CODEC_FRAME_LENGTH);
iter = Inlines.silk_RSHIFT(frame_length, SilkConstants.LOG2_SHELL_CODEC_FRAME_LENGTH);
if (iter * SilkConstants.SHELL_CODEC_FRAME_LENGTH < frame_length)
{
Inlines.OpusAssert(frame_length == 12 * 10); /* Make sure only happens for 10 ms @ 12 kHz */
iter++;
}
/***************************************************/
/* Sum-Weighted-Pulses Decoding */
/***************************************************/
for (i = 0; i < iter; i++)
{
nLshifts[i] = 0;
sum_pulses[i] = psRangeDec.dec_icdf(Tables.silk_pulses_per_block_iCDF[RateLevelIndex], 8);
/* LSB indication */
while (sum_pulses[i] == SilkConstants.SILK_MAX_PULSES + 1)
{
nLshifts[i]++;
/* When we've already got 10 LSBs, we shift the table to not allow (SILK_MAX_PULSES + 1) */
sum_pulses[i] = psRangeDec.dec_icdf(
Tables.silk_pulses_per_block_iCDF[SilkConstants.N_RATE_LEVELS - 1], (nLshifts[i] == 10 ? 1 : 0), 8);
}
}
/***************************************************/
/* Shell decoding */
/***************************************************/
for (i = 0; i < iter; i++)
{
if (sum_pulses[i] > 0)
{
ShellCoder.silk_shell_decoder(pulses, Inlines.silk_SMULBB(i, SilkConstants.SHELL_CODEC_FRAME_LENGTH), psRangeDec, sum_pulses[i]);
}
else
{
Arrays.MemSetWithOffset <short>(pulses, 0, Inlines.silk_SMULBB(i, SilkConstants.SHELL_CODEC_FRAME_LENGTH), SilkConstants.SHELL_CODEC_FRAME_LENGTH);
}
}
/***************************************************/
/* LSB Decoding */
/***************************************************/
for (i = 0; i < iter; i++)
{
if (nLshifts[i] > 0)
{
nLS = nLshifts[i];
pulses_ptr = Inlines.silk_SMULBB(i, SilkConstants.SHELL_CODEC_FRAME_LENGTH);
for (k = 0; k < SilkConstants.SHELL_CODEC_FRAME_LENGTH; k++)
{
abs_q = pulses[pulses_ptr + k];
for (j = 0; j < nLS; j++)
{
abs_q = Inlines.silk_LSHIFT(abs_q, 1);
abs_q += psRangeDec.dec_icdf(Tables.silk_lsb_iCDF, 8);
}
pulses[pulses_ptr + k] = (short)(abs_q);
}
/* Mark the number of pulses non-zero for sign decoding. */
sum_pulses[i] |= nLS << 5;
}
}
/****************************************/
/* Decode and add signs to pulse signal */
/****************************************/
CodeSigns.silk_decode_signs(psRangeDec, pulses, frame_length, signalType, quantOffsetType, sum_pulses);
}