1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 /* 12 * decode.c 13 * 14 * This C file contains the internal decoding function. 15 * 16 */ 17 18 #include <string.h> 19 20 #include "bandwidth_estimator.h" 21 #include "codec.h" 22 #include "entropy_coding.h" 23 #include "pitch_estimator.h" 24 #include "settings.h" 25 #include "structs.h" 26 27 28 29 30 int WebRtcIsacfix_DecodeImpl(int16_t* signal_out16, 31 IsacFixDecoderInstance* ISACdec_obj, 32 size_t* current_framesamples) 33 { 34 int k; 35 int err; 36 int16_t BWno; 37 int len = 0; 38 39 int16_t model; 40 41 42 int16_t Vector_Word16_1[FRAMESAMPLES/2]; 43 int16_t Vector_Word16_2[FRAMESAMPLES/2]; 44 45 int32_t Vector_Word32_1[FRAMESAMPLES/2]; 46 int32_t Vector_Word32_2[FRAMESAMPLES/2]; 47 48 int16_t lofilt_coefQ15[ORDERLO*SUBFRAMES]; //refl. coeffs 49 int16_t hifilt_coefQ15[ORDERHI*SUBFRAMES]; //refl. coeffs 50 int32_t gain_lo_hiQ17[2*SUBFRAMES]; 51 52 int16_t PitchLags_Q7[PITCH_SUBFRAMES]; 53 int16_t PitchGains_Q12[PITCH_SUBFRAMES]; 54 int16_t AvgPitchGain_Q12; 55 56 int16_t tmp_1, tmp_2; 57 int32_t tmp32a; 58 int16_t gainQ13; 59 60 61 size_t frame_nb; /* counter */ 62 size_t frame_mode; /* 0 for 30ms, 1 for 60ms */ 63 static const size_t kProcessedSamples = 480; /* 480 (for both 30, 60 ms) */ 64 65 /* PLC */ 66 int16_t overlapWin[ 240 ]; 67 68 (ISACdec_obj->bitstr_obj).W_upper = 0xFFFFFFFF; 69 (ISACdec_obj->bitstr_obj).streamval = 0; 70 (ISACdec_obj->bitstr_obj).stream_index = 0; 71 (ISACdec_obj->bitstr_obj).full = 1; 72 73 74 /* decode framelength and BW estimation - not used, only for stream pointer*/ 75 err = WebRtcIsacfix_DecodeFrameLen(&ISACdec_obj->bitstr_obj, current_framesamples); 76 if (err<0) // error check 77 return err; 78 79 frame_mode = *current_framesamples / MAX_FRAMESAMPLES; /* 0, or 1 */ 80 81 err = WebRtcIsacfix_DecodeSendBandwidth(&ISACdec_obj->bitstr_obj, &BWno); 82 if (err<0) // error check 83 return err; 84 85 /* one loop if it's one frame (30ms), two loops if two frames bundled together 86 * (60ms) */ 87 for (frame_nb = 0; frame_nb <= frame_mode; frame_nb++) { 88 89 /* decode & dequantize pitch parameters */ 90 err = WebRtcIsacfix_DecodePitchGain(&(ISACdec_obj->bitstr_obj), PitchGains_Q12); 91 if (err<0) // error check 92 return err; 93 94 err = WebRtcIsacfix_DecodePitchLag(&ISACdec_obj->bitstr_obj, PitchGains_Q12, PitchLags_Q7); 95 if (err<0) // error check 96 return err; 97 98 AvgPitchGain_Q12 = (int16_t)(((int32_t)PitchGains_Q12[0] + PitchGains_Q12[1] + PitchGains_Q12[2] + PitchGains_Q12[3])>>2); 99 100 /* decode & dequantize FiltCoef */ 101 err = WebRtcIsacfix_DecodeLpc(gain_lo_hiQ17, lofilt_coefQ15, hifilt_coefQ15, 102 &ISACdec_obj->bitstr_obj, &model); 103 104 if (err<0) // error check 105 return err; 106 107 /* decode & dequantize spectrum */ 108 len = WebRtcIsacfix_DecodeSpec(&ISACdec_obj->bitstr_obj, Vector_Word16_1, Vector_Word16_2, AvgPitchGain_Q12); 109 if (len < 0) // error check 110 return len; 111 112 // Why does this need Q16 in and out? /JS 113 WebRtcIsacfix_Spec2Time(Vector_Word16_1, Vector_Word16_2, Vector_Word32_1, Vector_Word32_2); 114 115 for (k=0; k<FRAMESAMPLES/2; k++) { 116 // Q16 -> Q9. 117 Vector_Word16_1[k] = (int16_t)((Vector_Word32_1[k] + 64) >> 7); 118 } 119 120 /* ---- If this is recovery frame ---- */ 121 if( (ISACdec_obj->plcstr_obj).used == PLC_WAS_USED ) 122 { 123 (ISACdec_obj->plcstr_obj).used = PLC_NOT_USED; 124 if( (ISACdec_obj->plcstr_obj).B < 1000 ) 125 { 126 (ISACdec_obj->plcstr_obj).decayCoeffPriodic = 4000; 127 } 128 129 ISACdec_obj->plcstr_obj.decayCoeffPriodic = WEBRTC_SPL_WORD16_MAX; /* DECAY_RATE is in Q15 */ 130 ISACdec_obj->plcstr_obj.decayCoeffNoise = WEBRTC_SPL_WORD16_MAX; /* DECAY_RATE is in Q15 */ 131 ISACdec_obj->plcstr_obj.pitchCycles = 0; 132 133 PitchGains_Q12[0] = (int16_t)(PitchGains_Q12[0] * 700 >> 10); 134 135 /* ---- Add-overlap ---- */ 136 WebRtcSpl_GetHanningWindow( overlapWin, RECOVERY_OVERLAP ); 137 for( k = 0; k < RECOVERY_OVERLAP; k++ ) 138 Vector_Word16_1[k] = WebRtcSpl_AddSatW16( 139 (int16_t)(ISACdec_obj->plcstr_obj.overlapLP[k] * 140 overlapWin[RECOVERY_OVERLAP - k - 1] >> 14), 141 (int16_t)(Vector_Word16_1[k] * overlapWin[k] >> 14)); 142 143 144 145 } 146 147 /* --- Store side info --- */ 148 if( frame_nb == frame_mode ) 149 { 150 /* --- LPC info */ 151 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).lofilt_coefQ15, &lofilt_coefQ15[(SUBFRAMES-1)*ORDERLO], ORDERLO ); 152 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).hifilt_coefQ15, &hifilt_coefQ15[(SUBFRAMES-1)*ORDERHI], ORDERHI ); 153 (ISACdec_obj->plcstr_obj).gain_lo_hiQ17[0] = gain_lo_hiQ17[(SUBFRAMES-1) * 2]; 154 (ISACdec_obj->plcstr_obj).gain_lo_hiQ17[1] = gain_lo_hiQ17[(SUBFRAMES-1) * 2 + 1]; 155 156 /* --- LTP info */ 157 (ISACdec_obj->plcstr_obj).AvgPitchGain_Q12 = PitchGains_Q12[3]; 158 (ISACdec_obj->plcstr_obj).lastPitchGain_Q12 = PitchGains_Q12[3]; 159 (ISACdec_obj->plcstr_obj).lastPitchLag_Q7 = PitchLags_Q7[3]; 160 161 if( PitchLags_Q7[3] < 3000 ) 162 (ISACdec_obj->plcstr_obj).lastPitchLag_Q7 += PitchLags_Q7[3]; 163 164 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).prevPitchInvIn, Vector_Word16_1, FRAMESAMPLES/2 ); 165 166 } 167 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ 168 169 /* inverse pitch filter */ 170 WebRtcIsacfix_PitchFilter(Vector_Word16_1, Vector_Word16_2, &ISACdec_obj->pitchfiltstr_obj, PitchLags_Q7, PitchGains_Q12, 4); 171 172 if( frame_nb == frame_mode ) 173 { 174 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).prevPitchInvOut, &(Vector_Word16_2[FRAMESAMPLES/2 - (PITCH_MAX_LAG + 10)]), PITCH_MAX_LAG ); 175 } 176 177 178 /* reduce gain to compensate for pitch enhancer */ 179 /* gain = 1.0f - 0.45f * AvgPitchGain; */ 180 tmp32a = AvgPitchGain_Q12 * 29; // Q18 181 gainQ13 = (int16_t)((262144 - tmp32a) >> 5); // Q18 -> Q13. 182 183 for (k = 0; k < FRAMESAMPLES/2; k++) 184 { 185 Vector_Word32_1[k] = (Vector_Word16_2[k] * gainQ13) << 3; // Q25 186 } 187 188 189 /* perceptual post-filtering (using normalized lattice filter) */ 190 WebRtcIsacfix_NormLatticeFilterAr(ORDERLO, (ISACdec_obj->maskfiltstr_obj).PostStateLoGQ0, 191 Vector_Word32_1, lofilt_coefQ15, gain_lo_hiQ17, 0, Vector_Word16_1); 192 193 /* --- Store Highpass Residual --- */ 194 for (k = 0; k < FRAMESAMPLES/2; k++) 195 Vector_Word32_1[k] = Vector_Word32_2[k] << 9; // Q16 -> Q25 196 197 for( k = 0; k < PITCH_MAX_LAG + 10; k++ ) 198 (ISACdec_obj->plcstr_obj).prevHP[k] = Vector_Word32_1[FRAMESAMPLES/2 - (PITCH_MAX_LAG + 10) + k]; 199 200 201 WebRtcIsacfix_NormLatticeFilterAr(ORDERHI, (ISACdec_obj->maskfiltstr_obj).PostStateHiGQ0, 202 Vector_Word32_1, hifilt_coefQ15, gain_lo_hiQ17, 1, Vector_Word16_2); 203 204 /* recombine the 2 bands */ 205 206 /* Form the polyphase signals, and compensate for DC offset */ 207 for (k=0;k<FRAMESAMPLES/2;k++) { 208 tmp_1 = (int16_t)WebRtcSpl_SatW32ToW16(((int32_t)Vector_Word16_1[k]+Vector_Word16_2[k] + 1)); /* Construct a new upper channel signal*/ 209 tmp_2 = (int16_t)WebRtcSpl_SatW32ToW16(((int32_t)Vector_Word16_1[k]-Vector_Word16_2[k])); /* Construct a new lower channel signal*/ 210 Vector_Word16_1[k] = tmp_1; 211 Vector_Word16_2[k] = tmp_2; 212 } 213 214 WebRtcIsacfix_FilterAndCombine1(Vector_Word16_1, 215 Vector_Word16_2, 216 signal_out16 + frame_nb * kProcessedSamples, 217 &ISACdec_obj->postfiltbankstr_obj); 218 219 } 220 return len; 221 } 222
