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 * WebRtcIsacfix_kTransform.c
13 *
14 * Transform functions
15 *
16 */
17
18 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h"
19 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/fft.h"
20 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/settings.h"
21
22 /* Tables are defined in transform_tables.c file or ARM assembly files. */
23 /* Cosine table 1 in Q14 */
24 extern const int16_t WebRtcIsacfix_kCosTab1[FRAMESAMPLES/2];
25 /* Sine table 1 in Q14 */
26 extern const int16_t WebRtcIsacfix_kSinTab1[FRAMESAMPLES/2];
27 /* Sine table 2 in Q14 */
28 extern const int16_t WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4];
29
WebRtcIsacfix_Time2SpecC(int16_t * inre1Q9,int16_t * inre2Q9,int16_t * outreQ7,int16_t * outimQ7)30 void WebRtcIsacfix_Time2SpecC(int16_t *inre1Q9,
31 int16_t *inre2Q9,
32 int16_t *outreQ7,
33 int16_t *outimQ7)
34 {
35
36 int k;
37 int32_t tmpreQ16[FRAMESAMPLES/2], tmpimQ16[FRAMESAMPLES/2];
38 int16_t tmp1rQ14, tmp1iQ14;
39 int32_t xrQ16, xiQ16, yrQ16, yiQ16;
40 int32_t v1Q16, v2Q16;
41 int16_t factQ19, sh;
42
43 /* Multiply with complex exponentials and combine into one complex vector */
44 factQ19 = 16921; // 0.5/sqrt(240) in Q19 is round(.5/sqrt(240)*(2^19)) = 16921
45 for (k = 0; k < FRAMESAMPLES/2; k++) {
46 tmp1rQ14 = WebRtcIsacfix_kCosTab1[k];
47 tmp1iQ14 = WebRtcIsacfix_kSinTab1[k];
48 xrQ16 = (tmp1rQ14 * inre1Q9[k] + tmp1iQ14 * inre2Q9[k]) >> 7;
49 xiQ16 = (tmp1rQ14 * inre2Q9[k] - tmp1iQ14 * inre1Q9[k]) >> 7;
50 // Q-domains below: (Q16*Q19>>16)>>3 = Q16
51 tmpreQ16[k] = (WEBRTC_SPL_MUL_16_32_RSFT16(factQ19, xrQ16) + 4) >> 3;
52 tmpimQ16[k] = (WEBRTC_SPL_MUL_16_32_RSFT16(factQ19, xiQ16) + 4) >> 3;
53 }
54
55
56 xrQ16 = WebRtcSpl_MaxAbsValueW32(tmpreQ16, FRAMESAMPLES/2);
57 yrQ16 = WebRtcSpl_MaxAbsValueW32(tmpimQ16, FRAMESAMPLES/2);
58 if (yrQ16>xrQ16) {
59 xrQ16 = yrQ16;
60 }
61
62 sh = WebRtcSpl_NormW32(xrQ16);
63 sh = sh-24; //if sh becomes >=0, then we should shift sh steps to the left, and the domain will become Q(16+sh)
64 //if sh becomes <0, then we should shift -sh steps to the right, and the domain will become Q(16+sh)
65
66 //"Fastest" vectors
67 if (sh>=0) {
68 for (k=0; k<FRAMESAMPLES/2; k++) {
69 inre1Q9[k] = (int16_t)(tmpreQ16[k] << sh); // Q(16+sh)
70 inre2Q9[k] = (int16_t)(tmpimQ16[k] << sh); // Q(16+sh)
71 }
72 } else {
73 int32_t round = 1 << (-sh - 1);
74 for (k=0; k<FRAMESAMPLES/2; k++) {
75 inre1Q9[k] = (int16_t)((tmpreQ16[k] + round) >> -sh); // Q(16+sh)
76 inre2Q9[k] = (int16_t)((tmpimQ16[k] + round) >> -sh); // Q(16+sh)
77 }
78 }
79
80 /* Get DFT */
81 WebRtcIsacfix_FftRadix16Fastest(inre1Q9, inre2Q9, -1); // real call
82
83 //"Fastest" vectors
84 if (sh>=0) {
85 for (k=0; k<FRAMESAMPLES/2; k++) {
86 tmpreQ16[k] = inre1Q9[k] >> sh; // Q(16+sh) -> Q16
87 tmpimQ16[k] = inre2Q9[k] >> sh; // Q(16+sh) -> Q16
88 }
89 } else {
90 for (k=0; k<FRAMESAMPLES/2; k++) {
91 tmpreQ16[k] = inre1Q9[k] << -sh; // Q(16+sh) -> Q16
92 tmpimQ16[k] = inre2Q9[k] << -sh; // Q(16+sh) -> Q16
93 }
94 }
95
96
97 /* Use symmetry to separate into two complex vectors and center frames in time around zero */
98 for (k = 0; k < FRAMESAMPLES/4; k++) {
99 xrQ16 = tmpreQ16[k] + tmpreQ16[FRAMESAMPLES/2 - 1 - k];
100 yiQ16 = -tmpreQ16[k] + tmpreQ16[FRAMESAMPLES/2 - 1 - k];
101 xiQ16 = tmpimQ16[k] - tmpimQ16[FRAMESAMPLES/2 - 1 - k];
102 yrQ16 = tmpimQ16[k] + tmpimQ16[FRAMESAMPLES/2 - 1 - k];
103 tmp1rQ14 = -WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4 - 1 - k];
104 tmp1iQ14 = WebRtcIsacfix_kSinTab2[k];
105 v1Q16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, xrQ16) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, xiQ16);
106 v2Q16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, xrQ16) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, xiQ16);
107 outreQ7[k] = (int16_t)(v1Q16 >> 9);
108 outimQ7[k] = (int16_t)(v2Q16 >> 9);
109 v1Q16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, yrQ16) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, yiQ16);
110 v2Q16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, yrQ16) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, yiQ16);
111 // CalcLrIntQ(v1Q16, 9);
112 outreQ7[FRAMESAMPLES / 2 - 1 - k] = (int16_t)(v1Q16 >> 9);
113 // CalcLrIntQ(v2Q16, 9);
114 outimQ7[FRAMESAMPLES / 2 - 1 - k] = (int16_t)(v2Q16 >> 9);
115
116 }
117 }
118
119
WebRtcIsacfix_Spec2TimeC(int16_t * inreQ7,int16_t * inimQ7,int32_t * outre1Q16,int32_t * outre2Q16)120 void WebRtcIsacfix_Spec2TimeC(int16_t *inreQ7, int16_t *inimQ7, int32_t *outre1Q16, int32_t *outre2Q16)
121 {
122
123 int k;
124 int16_t tmp1rQ14, tmp1iQ14;
125 int32_t xrQ16, xiQ16, yrQ16, yiQ16;
126 int32_t tmpInRe, tmpInIm, tmpInRe2, tmpInIm2;
127 int16_t factQ11;
128 int16_t sh;
129
130 for (k = 0; k < FRAMESAMPLES/4; k++) {
131 /* Move zero in time to beginning of frames */
132 tmp1rQ14 = -WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4 - 1 - k];
133 tmp1iQ14 = WebRtcIsacfix_kSinTab2[k];
134
135 tmpInRe = inreQ7[k] << 9; // Q7 -> Q16
136 tmpInIm = inimQ7[k] << 9; // Q7 -> Q16
137 tmpInRe2 = inreQ7[FRAMESAMPLES / 2 - 1 - k] << 9; // Q7 -> Q16
138 tmpInIm2 = inimQ7[FRAMESAMPLES / 2 - 1 - k] << 9; // Q7 -> Q16
139
140 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInRe) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInIm);
141 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInIm) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInRe);
142 yrQ16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInIm2) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInRe2);
143 yiQ16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInRe2) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInIm2);
144
145 /* Combine into one vector, z = x + j * y */
146 outre1Q16[k] = xrQ16 - yiQ16;
147 outre1Q16[FRAMESAMPLES/2 - 1 - k] = xrQ16 + yiQ16;
148 outre2Q16[k] = xiQ16 + yrQ16;
149 outre2Q16[FRAMESAMPLES/2 - 1 - k] = -xiQ16 + yrQ16;
150 }
151
152 /* Get IDFT */
153 tmpInRe = WebRtcSpl_MaxAbsValueW32(outre1Q16, 240);
154 tmpInIm = WebRtcSpl_MaxAbsValueW32(outre2Q16, 240);
155 if (tmpInIm>tmpInRe) {
156 tmpInRe = tmpInIm;
157 }
158
159 sh = WebRtcSpl_NormW32(tmpInRe);
160 sh = sh-24; //if sh becomes >=0, then we should shift sh steps to the left, and the domain will become Q(16+sh)
161 //if sh becomes <0, then we should shift -sh steps to the right, and the domain will become Q(16+sh)
162
163 //"Fastest" vectors
164 if (sh>=0) {
165 for (k=0; k<240; k++) {
166 inreQ7[k] = (int16_t)(outre1Q16[k] << sh); // Q(16+sh)
167 inimQ7[k] = (int16_t)(outre2Q16[k] << sh); // Q(16+sh)
168 }
169 } else {
170 int32_t round = 1 << (-sh - 1);
171 for (k=0; k<240; k++) {
172 inreQ7[k] = (int16_t)((outre1Q16[k] + round) >> -sh); // Q(16+sh)
173 inimQ7[k] = (int16_t)((outre2Q16[k] + round) >> -sh); // Q(16+sh)
174 }
175 }
176
177 WebRtcIsacfix_FftRadix16Fastest(inreQ7, inimQ7, 1); // real call
178
179 //"Fastest" vectors
180 if (sh>=0) {
181 for (k=0; k<240; k++) {
182 outre1Q16[k] = inreQ7[k] >> sh; // Q(16+sh) -> Q16
183 outre2Q16[k] = inimQ7[k] >> sh; // Q(16+sh) -> Q16
184 }
185 } else {
186 for (k=0; k<240; k++) {
187 outre1Q16[k] = inreQ7[k] << -sh; // Q(16+sh) -> Q16
188 outre2Q16[k] = inimQ7[k] << -sh; // Q(16+sh) -> Q16
189 }
190 }
191
192 /* Divide through by the normalizing constant: */
193 /* scale all values with 1/240, i.e. with 273 in Q16 */
194 /* 273/65536 ~= 0.0041656 */
195 /* 1/240 ~= 0.0041666 */
196 for (k=0; k<240; k++) {
197 outre1Q16[k] = WEBRTC_SPL_MUL_16_32_RSFT16(273, outre1Q16[k]);
198 outre2Q16[k] = WEBRTC_SPL_MUL_16_32_RSFT16(273, outre2Q16[k]);
199 }
200
201 /* Demodulate and separate */
202 factQ11 = 31727; // sqrt(240) in Q11 is round(15.49193338482967*2048) = 31727
203 for (k = 0; k < FRAMESAMPLES/2; k++) {
204 tmp1rQ14 = WebRtcIsacfix_kCosTab1[k];
205 tmp1iQ14 = WebRtcIsacfix_kSinTab1[k];
206 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, outre1Q16[k]) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, outre2Q16[k]);
207 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, outre2Q16[k]) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, outre1Q16[k]);
208 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT11(factQ11, xrQ16);
209 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT11(factQ11, xiQ16);
210 outre2Q16[k] = xiQ16;
211 outre1Q16[k] = xrQ16;
212 }
213 }
214