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 WebRtc_Word16 WebRtcIsacfix_DecodeImpl(WebRtc_Word16 *signal_out16, 31 ISACFIX_DecInst_t *ISACdec_obj, 32 WebRtc_Word16 *current_framesamples) 33 { 34 int k; 35 int err; 36 WebRtc_Word16 BWno; 37 WebRtc_Word16 len = 0; 38 39 WebRtc_Word16 model; 40 41 42 WebRtc_Word16 Vector_Word16_1[FRAMESAMPLES/2]; 43 WebRtc_Word16 Vector_Word16_2[FRAMESAMPLES/2]; 44 45 WebRtc_Word32 Vector_Word32_1[FRAMESAMPLES/2]; 46 WebRtc_Word32 Vector_Word32_2[FRAMESAMPLES/2]; 47 48 WebRtc_Word16 lofilt_coefQ15[ORDERLO*SUBFRAMES]; //refl. coeffs 49 WebRtc_Word16 hifilt_coefQ15[ORDERHI*SUBFRAMES]; //refl. coeffs 50 WebRtc_Word32 gain_lo_hiQ17[2*SUBFRAMES]; 51 52 WebRtc_Word16 PitchLags_Q7[PITCH_SUBFRAMES]; 53 WebRtc_Word16 PitchGains_Q12[PITCH_SUBFRAMES]; 54 WebRtc_Word16 AvgPitchGain_Q12; 55 56 WebRtc_Word16 tmp_1, tmp_2; 57 WebRtc_Word32 tmp32a, tmp32b; 58 WebRtc_Word16 gainQ13; 59 60 61 WebRtc_Word16 frame_nb; /* counter */ 62 WebRtc_Word16 frame_mode; /* 0 for 20ms and 30ms, 1 for 60ms */ 63 WebRtc_Word16 processed_samples; 64 65 /* PLC */ 66 WebRtc_Word16 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 = (WebRtc_Word16)WEBRTC_SPL_DIV(*current_framesamples, MAX_FRAMESAMPLES); /* 0, or 1 */ 80 processed_samples = (WebRtc_Word16)WEBRTC_SPL_DIV(*current_framesamples, frame_mode+1); /* either 320 (20ms) or 480 (30, 60 ms) */ 81 82 err = WebRtcIsacfix_DecodeSendBandwidth(&ISACdec_obj->bitstr_obj, &BWno); 83 if (err<0) // error check 84 return err; 85 86 /* one loop if it's one frame (20 or 30ms), 2 loops if 2 frames bundled together (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 = (WebRtc_Word16)(((WebRtc_Word32)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 Vector_Word16_1[k] = (WebRtc_Word16)WEBRTC_SPL_RSHIFT_W32(Vector_Word32_1[k]+64, 7); //Q16 -> Q9 117 } 118 119 /* ---- If this is recovery frame ---- */ 120 if( (ISACdec_obj->plcstr_obj).used == PLC_WAS_USED ) 121 { 122 (ISACdec_obj->plcstr_obj).used = PLC_NOT_USED; 123 if( (ISACdec_obj->plcstr_obj).B < 1000 ) 124 { 125 (ISACdec_obj->plcstr_obj).decayCoeffPriodic = 4000; 126 } 127 128 ISACdec_obj->plcstr_obj.decayCoeffPriodic = WEBRTC_SPL_WORD16_MAX; /* DECAY_RATE is in Q15 */ 129 ISACdec_obj->plcstr_obj.decayCoeffNoise = WEBRTC_SPL_WORD16_MAX; /* DECAY_RATE is in Q15 */ 130 ISACdec_obj->plcstr_obj.pitchCycles = 0; 131 132 PitchGains_Q12[0] = (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT(PitchGains_Q12[0], 700, 10 ); 133 134 /* ---- Add-overlap ---- */ 135 WebRtcSpl_GetHanningWindow( overlapWin, RECOVERY_OVERLAP ); 136 for( k = 0; k < RECOVERY_OVERLAP; k++ ) 137 Vector_Word16_1[k] = WEBRTC_SPL_ADD_SAT_W16( 138 (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT( (ISACdec_obj->plcstr_obj).overlapLP[k], overlapWin[RECOVERY_OVERLAP - k - 1], 14), 139 (WebRtc_Word16)WEBRTC_SPL_MUL_16_16_RSFT( Vector_Word16_1[k], overlapWin[k], 14) ); 140 141 142 143 } 144 145 /* --- Store side info --- */ 146 if( frame_nb == frame_mode ) 147 { 148 /* --- LPC info */ 149 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).lofilt_coefQ15, &lofilt_coefQ15[(SUBFRAMES-1)*ORDERLO], ORDERLO ); 150 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).hifilt_coefQ15, &hifilt_coefQ15[(SUBFRAMES-1)*ORDERHI], ORDERHI ); 151 (ISACdec_obj->plcstr_obj).gain_lo_hiQ17[0] = gain_lo_hiQ17[(SUBFRAMES-1) * 2]; 152 (ISACdec_obj->plcstr_obj).gain_lo_hiQ17[1] = gain_lo_hiQ17[(SUBFRAMES-1) * 2 + 1]; 153 154 /* --- LTP info */ 155 (ISACdec_obj->plcstr_obj).AvgPitchGain_Q12 = PitchGains_Q12[3]; 156 (ISACdec_obj->plcstr_obj).lastPitchGain_Q12 = PitchGains_Q12[3]; 157 (ISACdec_obj->plcstr_obj).lastPitchLag_Q7 = PitchLags_Q7[3]; 158 159 if( PitchLags_Q7[3] < 3000 ) 160 (ISACdec_obj->plcstr_obj).lastPitchLag_Q7 += PitchLags_Q7[3]; 161 162 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).prevPitchInvIn, Vector_Word16_1, FRAMESAMPLES/2 ); 163 164 } 165 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ 166 167 /* inverse pitch filter */ 168 WebRtcIsacfix_PitchFilter(Vector_Word16_1, Vector_Word16_2, &ISACdec_obj->pitchfiltstr_obj, PitchLags_Q7, PitchGains_Q12, 4); 169 170 if( frame_nb == frame_mode ) 171 { 172 WEBRTC_SPL_MEMCPY_W16( (ISACdec_obj->plcstr_obj).prevPitchInvOut, &(Vector_Word16_2[FRAMESAMPLES/2 - (PITCH_MAX_LAG + 10)]), PITCH_MAX_LAG ); 173 } 174 175 176 /* reduce gain to compensate for pitch enhancer */ 177 /* gain = 1.0f - 0.45f * AvgPitchGain; */ 178 tmp32a = WEBRTC_SPL_MUL_16_16_RSFT(AvgPitchGain_Q12, 29, 0); // Q18 179 tmp32b = 262144 - tmp32a; // Q18 180 gainQ13 = (WebRtc_Word16) WEBRTC_SPL_RSHIFT_W32(tmp32b, 5); // Q13 181 182 for (k = 0; k < FRAMESAMPLES/2; k++) 183 { 184 Vector_Word32_1[k] = (WebRtc_Word32) WEBRTC_SPL_LSHIFT_W32(WEBRTC_SPL_MUL_16_16(Vector_Word16_2[k], gainQ13), 3); // Q25 185 } 186 187 188 /* perceptual post-filtering (using normalized lattice filter) */ 189 WebRtcIsacfix_NormLatticeFilterAr(ORDERLO, (ISACdec_obj->maskfiltstr_obj).PostStateLoGQ0, 190 Vector_Word32_1, lofilt_coefQ15, gain_lo_hiQ17, 0, Vector_Word16_1); 191 192 /* --- Store Highpass Residual --- */ 193 for (k = 0; k < FRAMESAMPLES/2; k++) 194 Vector_Word32_1[k] = WEBRTC_SPL_LSHIFT_W32(Vector_Word32_2[k], 9); // Q16 -> Q25 195 196 for( k = 0; k < PITCH_MAX_LAG + 10; k++ ) 197 (ISACdec_obj->plcstr_obj).prevHP[k] = Vector_Word32_1[FRAMESAMPLES/2 - (PITCH_MAX_LAG + 10) + k]; 198 199 200 WebRtcIsacfix_NormLatticeFilterAr(ORDERHI, (ISACdec_obj->maskfiltstr_obj).PostStateHiGQ0, 201 Vector_Word32_1, hifilt_coefQ15, gain_lo_hiQ17, 1, Vector_Word16_2); 202 203 /* recombine the 2 bands */ 204 205 /* Form the polyphase signals, and compensate for DC offset */ 206 for (k=0;k<FRAMESAMPLES/2;k++) { 207 tmp_1 = (WebRtc_Word16)WebRtcSpl_SatW32ToW16(((WebRtc_Word32)Vector_Word16_1[k]+Vector_Word16_2[k] + 1)); /* Construct a new upper channel signal*/ 208 tmp_2 = (WebRtc_Word16)WebRtcSpl_SatW32ToW16(((WebRtc_Word32)Vector_Word16_1[k]-Vector_Word16_2[k])); /* Construct a new lower channel signal*/ 209 Vector_Word16_1[k] = tmp_1; 210 Vector_Word16_2[k] = tmp_2; 211 } 212 213 WebRtcIsacfix_FilterAndCombine1(Vector_Word16_1, Vector_Word16_2, signal_out16 + frame_nb * processed_samples, &ISACdec_obj->postfiltbankstr_obj); 214 215 } 216 return len; 217 } 218
