/* * Siren Encoder/Decoder library * * @author: Youness Alaoui * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #include "siren7.h" SirenEncoder Siren7_NewEncoder (int sample_rate) { SirenEncoder encoder = (SirenEncoder) malloc (sizeof (struct stSirenEncoder)); encoder->sample_rate = sample_rate; encoder->WavHeader.riff.RiffId = ME_TO_LE32 (RIFF_ID); encoder->WavHeader.riff.RiffSize = sizeof (SirenWavHeader) - 2 * sizeof (int); encoder->WavHeader.riff.RiffSize = ME_TO_LE32 (encoder->WavHeader.riff.RiffSize); encoder->WavHeader.WaveId = ME_TO_LE32 (WAVE_ID); encoder->WavHeader.FmtId = ME_TO_LE32 (FMT__ID); encoder->WavHeader.FmtSize = ME_TO_LE32 (sizeof (SirenFmtChunk)); encoder->WavHeader.fmt.fmt.Format = ME_TO_LE16 (0x028E); encoder->WavHeader.fmt.fmt.Channels = ME_TO_LE16 (1); encoder->WavHeader.fmt.fmt.SampleRate = ME_TO_LE32 (16000); encoder->WavHeader.fmt.fmt.ByteRate = ME_TO_LE32 (2000); encoder->WavHeader.fmt.fmt.BlockAlign = ME_TO_LE16 (40); encoder->WavHeader.fmt.fmt.BitsPerSample = ME_TO_LE16 (0); encoder->WavHeader.fmt.ExtraSize = ME_TO_LE16 (2); encoder->WavHeader.fmt.DctLength = ME_TO_LE16 (320); encoder->WavHeader.FactId = ME_TO_LE32 (FACT_ID); encoder->WavHeader.FactSize = ME_TO_LE32 (sizeof (int)); encoder->WavHeader.Samples = ME_TO_LE32 (0); encoder->WavHeader.DataId = ME_TO_LE32 (DATA_ID); encoder->WavHeader.DataSize = ME_TO_LE32 (0); memset (encoder->context, 0, sizeof (encoder->context)); siren_init (); return encoder; } void Siren7_CloseEncoder (SirenEncoder encoder) { free (encoder); } int Siren7_EncodeFrame (SirenEncoder encoder, unsigned char *DataIn, unsigned char *DataOut) { int number_of_coefs, sample_rate_bits, rate_control_bits, rate_control_possibilities, checksum_bits, esf_adjustment, scale_factor, number_of_regions, sample_rate_code, bits_per_frame; int sample_rate = encoder->sample_rate; int absolute_region_power_index[28] = { 0 }; int power_categories[28] = { 0 }; int category_balance[28] = { 0 }; int drp_num_bits[30] = { 0 }; int drp_code_bits[30] = { 0 }; int region_mlt_bit_counts[28] = { 0 }; int region_mlt_bits[112] = { 0 }; int ChecksumTable[4] = { 0x7F80, 0x7878, 0x6666, 0x5555 }; int i, j; int dwRes = 0; short out_word; int bits_left; int current_word_bits_left; int region_bit_count; unsigned int current_word; unsigned int sum; unsigned int checksum; int temp1 = 0; int temp2 = 0; int region; int idx = 0; int envelope_bits = 0; int rate_control; int number_of_available_bits; float coefs[320]; float In[320]; short BufferOut[20]; float *context = encoder->context; for (i = 0; i < 320; i++) In[i] = (float) ((short) ME_FROM_LE16 (((short *) DataIn)[i])); dwRes = siren_rmlt_encode_samples (In, context, 320, coefs); if (dwRes != 0) return dwRes; dwRes = GetSirenCodecInfo (1, sample_rate, &number_of_coefs, &sample_rate_bits, &rate_control_bits, &rate_control_possibilities, &checksum_bits, &esf_adjustment, &scale_factor, &number_of_regions, &sample_rate_code, &bits_per_frame); if (dwRes != 0) return dwRes; envelope_bits = compute_region_powers (number_of_regions, coefs, drp_num_bits, drp_code_bits, absolute_region_power_index, esf_adjustment); number_of_available_bits = bits_per_frame - rate_control_bits - envelope_bits - sample_rate_bits - checksum_bits; categorize_regions (number_of_regions, number_of_available_bits, absolute_region_power_index, power_categories, category_balance); for (region = 0; region < number_of_regions; region++) { absolute_region_power_index[region] += 24; region_mlt_bit_counts[region] = 0; } rate_control = quantize_mlt (number_of_regions, rate_control_possibilities, number_of_available_bits, coefs, absolute_region_power_index, power_categories, category_balance, region_mlt_bit_counts, region_mlt_bits); idx = 0; bits_left = 16 - sample_rate_bits; out_word = sample_rate_code << (16 - sample_rate_bits); drp_num_bits[number_of_regions] = rate_control_bits; drp_code_bits[number_of_regions] = rate_control; for (region = 0; region <= number_of_regions; region++) { i = drp_num_bits[region] - bits_left; if (i < 0) { out_word += drp_code_bits[region] << -i; bits_left -= drp_num_bits[region]; } else { BufferOut[idx++] = out_word + (drp_code_bits[region] >> i); bits_left += 16 - drp_num_bits[region]; out_word = drp_code_bits[region] << bits_left; } } for (region = 0; region < number_of_regions && (16 * idx) < bits_per_frame; region++) { current_word_bits_left = region_bit_count = region_mlt_bit_counts[region]; if (current_word_bits_left > 32) current_word_bits_left = 32; current_word = region_mlt_bits[region * 4]; i = 1; while (region_bit_count > 0 && (16 * idx) < bits_per_frame) { if (current_word_bits_left < bits_left) { bits_left -= current_word_bits_left; out_word += (current_word >> (32 - current_word_bits_left)) << bits_left; current_word_bits_left = 0; } else { BufferOut[idx++] = (short) (out_word + (current_word >> (32 - bits_left))); current_word_bits_left -= bits_left; current_word <<= bits_left; bits_left = 16; out_word = 0; } if (current_word_bits_left == 0) { region_bit_count -= 32; current_word = region_mlt_bits[(region * 4) + i++]; current_word_bits_left = region_bit_count; if (current_word_bits_left > 32) current_word_bits_left = 32; } } } while ((16 * idx) < bits_per_frame) { BufferOut[idx++] = (short) ((0xFFFF >> (16 - bits_left)) + out_word); bits_left = 16; out_word = 0; } if (checksum_bits > 0) { BufferOut[idx - 1] &= (-1 << checksum_bits); sum = 0; idx = 0; do { sum ^= (BufferOut[idx] & 0xFFFF) << (idx % 15); } while ((16 * ++idx) < bits_per_frame); sum = (sum >> 15) ^ (sum & 0x7FFF); checksum = 0; for (i = 0; i < 4; i++) { temp1 = ChecksumTable[i] & sum; for (j = 8; j > 0; j >>= 1) { temp2 = temp1 >> j; temp1 ^= temp2; } checksum <<= 1; checksum |= temp1 & 1; } BufferOut[idx - 1] |= ((1 << checksum_bits) - 1) & checksum; } for (i = 0; i < 20; i++) #ifdef __BIG_ENDIAN__ ((short *) DataOut)[i] = BufferOut[i]; #else ((short *) DataOut)[i] = ((BufferOut[i] << 8) & 0xFF00) | ((BufferOut[i] >> 8) & 0x00FF); #endif encoder->WavHeader.Samples = ME_FROM_LE32 (encoder->WavHeader.Samples); encoder->WavHeader.Samples += 320; encoder->WavHeader.Samples = ME_TO_LE32 (encoder->WavHeader.Samples); encoder->WavHeader.DataSize = ME_FROM_LE32 (encoder->WavHeader.DataSize); encoder->WavHeader.DataSize += 40; encoder->WavHeader.DataSize = ME_TO_LE32 (encoder->WavHeader.DataSize); encoder->WavHeader.riff.RiffSize = ME_FROM_LE32 (encoder->WavHeader.riff.RiffSize); encoder->WavHeader.riff.RiffSize += 40; encoder->WavHeader.riff.RiffSize = ME_TO_LE32 (encoder->WavHeader.riff.RiffSize); return 0; }