Asterisk - The Open Source Telephony Project GIT-master-2de1a68
g722_encode.c
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1/*
2 * SpanDSP - a series of DSP components for telephony
3 *
4 * g722_encode.c - The ITU G.722 codec, encode part.
5 *
6 * Written by Steve Underwood <steveu@coppice.org>
7 *
8 * Copyright (C) 2005 Steve Underwood
9 *
10 * All rights reserved.
11 *
12 * Despite my general liking of the GPL, I place my own contributions
13 * to this code in the public domain for the benefit of all mankind -
14 * even the slimy ones who might try to proprietize my work and use it
15 * to my detriment.
16 *
17 * Based on a single channel 64kbps only G.722 codec which is:
18 *
19 ***** Copyright (c) CMU 1993 *****
20 * Computer Science, Speech Group
21 * Chengxiang Lu and Alex Hauptmann
22 *
23 * $Id$
24 */
25
26/*! \file */
27
28#ifdef HAVE_CONFIG_H
29#include <config.h>
30#endif
31
32#include <stdio.h>
33#include <inttypes.h>
34#include <memory.h>
35#include <stdlib.h>
36#if 0
37#include <tgmath.h>
38#endif
39
40#include "g722.h"
41
42#if !defined(FALSE)
43#define FALSE 0
44#endif
45#if !defined(TRUE)
46#define TRUE (!FALSE)
47#endif
48
49static __inline__ int16_t saturate(int32_t amp)
50{
51 int16_t amp16;
52
53 /* Hopefully this is optimised for the common case - not clipping */
54 amp16 = (int16_t) amp;
55 if (amp == amp16)
56 return amp16;
57 if (amp > INT16_MAX)
58 return INT16_MAX;
59 return INT16_MIN;
60}
61/*- End of function --------------------------------------------------------*/
62
63static void block4(g722_encode_state_t *s, int band, int d)
64{
65 int wd1;
66 int wd2;
67 int wd3;
68 int i;
69
70 /* Block 4, RECONS */
71 s->band[band].d[0] = d;
72 s->band[band].r[0] = saturate(s->band[band].s + d);
73
74 /* Block 4, PARREC */
75 s->band[band].p[0] = saturate(s->band[band].sz + d);
76
77 /* Block 4, UPPOL2 */
78 for (i = 0; i < 3; i++)
79 s->band[band].sg[i] = s->band[band].p[i] >> 15;
80 wd1 = saturate(s->band[band].a[1] << 2);
81
82 wd2 = (s->band[band].sg[0] == s->band[band].sg[1]) ? -wd1 : wd1;
83 if (wd2 > 32767)
84 wd2 = 32767;
85 wd3 = (wd2 >> 7) + ((s->band[band].sg[0] == s->band[band].sg[2]) ? 128 : -128);
86 wd3 += (s->band[band].a[2]*32512) >> 15;
87 if (wd3 > 12288)
88 wd3 = 12288;
89 else if (wd3 < -12288)
90 wd3 = -12288;
91 s->band[band].ap[2] = wd3;
92
93 /* Block 4, UPPOL1 */
94 s->band[band].sg[0] = s->band[band].p[0] >> 15;
95 s->band[band].sg[1] = s->band[band].p[1] >> 15;
96 wd1 = (s->band[band].sg[0] == s->band[band].sg[1]) ? 192 : -192;
97 wd2 = (s->band[band].a[1]*32640) >> 15;
98
99 s->band[band].ap[1] = saturate(wd1 + wd2);
100 wd3 = saturate(15360 - s->band[band].ap[2]);
101 if (s->band[band].ap[1] > wd3)
102 s->band[band].ap[1] = wd3;
103 else if (s->band[band].ap[1] < -wd3)
104 s->band[band].ap[1] = -wd3;
105
106 /* Block 4, UPZERO */
107 wd1 = (d == 0) ? 0 : 128;
108 s->band[band].sg[0] = d >> 15;
109 for (i = 1; i < 7; i++)
110 {
111 s->band[band].sg[i] = s->band[band].d[i] >> 15;
112 wd2 = (s->band[band].sg[i] == s->band[band].sg[0]) ? wd1 : -wd1;
113 wd3 = (s->band[band].b[i]*32640) >> 15;
114 s->band[band].bp[i] = saturate(wd2 + wd3);
115 }
116
117 /* Block 4, DELAYA */
118 for (i = 6; i > 0; i--)
119 {
120 s->band[band].d[i] = s->band[band].d[i - 1];
121 s->band[band].b[i] = s->band[band].bp[i];
122 }
123
124 for (i = 2; i > 0; i--)
125 {
126 s->band[band].r[i] = s->band[band].r[i - 1];
127 s->band[band].p[i] = s->band[band].p[i - 1];
128 s->band[band].a[i] = s->band[band].ap[i];
129 }
130
131 /* Block 4, FILTEP */
132 wd1 = saturate(s->band[band].r[1] + s->band[band].r[1]);
133 wd1 = (s->band[band].a[1]*wd1) >> 15;
134 wd2 = saturate(s->band[band].r[2] + s->band[band].r[2]);
135 wd2 = (s->band[band].a[2]*wd2) >> 15;
136 s->band[band].sp = saturate(wd1 + wd2);
137
138 /* Block 4, FILTEZ */
139 s->band[band].sz = 0;
140 for (i = 6; i > 0; i--)
141 {
142 wd1 = saturate(s->band[band].d[i] + s->band[band].d[i]);
143 s->band[band].sz += (s->band[band].b[i]*wd1) >> 15;
144 }
145 s->band[band].sz = saturate(s->band[band].sz);
146
147 /* Block 4, PREDIC */
148 s->band[band].s = saturate(s->band[band].sp + s->band[band].sz);
149}
150/*- End of function --------------------------------------------------------*/
151
153{
154 if (s == NULL)
155 {
156 if ((s = (g722_encode_state_t *) malloc(sizeof(*s))) == NULL)
157 return NULL;
158 }
159 memset(s, 0, sizeof(*s));
160 if (rate == 48000)
161 s->bits_per_sample = 6;
162 else if (rate == 56000)
163 s->bits_per_sample = 7;
164 else
165 s->bits_per_sample = 8;
167 s->eight_k = TRUE;
168 if ((options & G722_PACKED) && s->bits_per_sample != 8)
169 s->packed = TRUE;
170 else
171 s->packed = FALSE;
172 s->band[0].det = 32;
173 s->band[1].det = 8;
174 return s;
175}
176/*- End of function --------------------------------------------------------*/
177
179{
180 free(s);
181 return 0;
182}
183/*- End of function --------------------------------------------------------*/
184
185int g722_encode(g722_encode_state_t *s, uint8_t g722_data[], const int16_t amp[], int len)
186{
187 static const int q6[32] =
188 {
189 0, 35, 72, 110, 150, 190, 233, 276,
190 323, 370, 422, 473, 530, 587, 650, 714,
191 786, 858, 940, 1023, 1121, 1219, 1339, 1458,
192 1612, 1765, 1980, 2195, 2557, 2919, 0, 0
193 };
194 static const int iln[32] =
195 {
196 0, 63, 62, 31, 30, 29, 28, 27,
197 26, 25, 24, 23, 22, 21, 20, 19,
198 18, 17, 16, 15, 14, 13, 12, 11,
199 10, 9, 8, 7, 6, 5, 4, 0
200 };
201 static const int ilp[32] =
202 {
203 0, 61, 60, 59, 58, 57, 56, 55,
204 54, 53, 52, 51, 50, 49, 48, 47,
205 46, 45, 44, 43, 42, 41, 40, 39,
206 38, 37, 36, 35, 34, 33, 32, 0
207 };
208 static const int wl[8] =
209 {
210 -60, -30, 58, 172, 334, 538, 1198, 3042
211 };
212 static const int rl42[16] =
213 {
214 0, 7, 6, 5, 4, 3, 2, 1, 7, 6, 5, 4, 3, 2, 1, 0
215 };
216 static const int ilb[32] =
217 {
218 2048, 2093, 2139, 2186, 2233, 2282, 2332,
219 2383, 2435, 2489, 2543, 2599, 2656, 2714,
220 2774, 2834, 2896, 2960, 3025, 3091, 3158,
221 3228, 3298, 3371, 3444, 3520, 3597, 3676,
222 3756, 3838, 3922, 4008
223 };
224 static const int qm4[16] =
225 {
226 0, -20456, -12896, -8968,
227 -6288, -4240, -2584, -1200,
228 20456, 12896, 8968, 6288,
229 4240, 2584, 1200, 0
230 };
231 static const int qm2[4] =
232 {
233 -7408, -1616, 7408, 1616
234 };
235 static const int qmf_coeffs[12] =
236 {
237 3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11,
238 };
239 static const int ihn[3] = {0, 1, 0};
240 static const int ihp[3] = {0, 3, 2};
241 static const int wh[3] = {0, -214, 798};
242 static const int rh2[4] = {2, 1, 2, 1};
243
244 int dlow;
245 int dhigh;
246 int el;
247 int wd;
248 int wd1;
249 int ril;
250 int wd2;
251 int il4;
252 int ih2;
253 int wd3;
254 int eh;
255 int mih;
256 int i;
257 int j;
258 /* Low and high band PCM from the QMF */
259 int xlow;
260 int xhigh;
261 int g722_bytes;
262 /* Even and odd tap accumulators */
263 int sumeven;
264 int sumodd;
265 int ihigh;
266 int ilow;
267 int code;
268
269 g722_bytes = 0;
270 xhigh = 0;
271 for (j = 0; j < len; )
272 {
273 if (s->itu_test_mode)
274 {
275 xlow =
276 xhigh = amp[j++] >> 1;
277 }
278 else
279 {
280 if (s->eight_k)
281 {
282 xlow = amp[j++] >> 1;
283 }
284 else
285 {
286 /* Apply the transmit QMF */
287 /* Shuffle the buffer down */
288 for (i = 0; i < 22; i++)
289 s->x[i] = s->x[i + 2];
290 s->x[22] = amp[j++];
291 s->x[23] = amp[j++];
292
293 /* Discard every other QMF output */
294 sumeven = 0;
295 sumodd = 0;
296 for (i = 0; i < 12; i++)
297 {
298 sumodd += s->x[2*i]*qmf_coeffs[i];
299 sumeven += s->x[2*i + 1]*qmf_coeffs[11 - i];
300 }
301 xlow = (sumeven + sumodd) >> 14;
302 xhigh = (sumeven - sumodd) >> 14;
303 }
304 }
305 /* Block 1L, SUBTRA */
306 el = saturate(xlow - s->band[0].s);
307
308 /* Block 1L, QUANTL */
309 wd = (el >= 0) ? el : -(el + 1);
310
311 for (i = 1; i < 30; i++)
312 {
313 wd1 = (q6[i]*s->band[0].det) >> 12;
314 if (wd < wd1)
315 break;
316 }
317 ilow = (el < 0) ? iln[i] : ilp[i];
318
319 /* Block 2L, INVQAL */
320 ril = ilow >> 2;
321 wd2 = qm4[ril];
322 dlow = (s->band[0].det*wd2) >> 15;
323
324 /* Block 3L, LOGSCL */
325 il4 = rl42[ril];
326 wd = (s->band[0].nb*127) >> 7;
327 s->band[0].nb = wd + wl[il4];
328 if (s->band[0].nb < 0)
329 s->band[0].nb = 0;
330 else if (s->band[0].nb > 18432)
331 s->band[0].nb = 18432;
332
333 /* Block 3L, SCALEL */
334 wd1 = (s->band[0].nb >> 6) & 31;
335 wd2 = 8 - (s->band[0].nb >> 11);
336 wd3 = (wd2 < 0) ? (ilb[wd1] << -wd2) : (ilb[wd1] >> wd2);
337 s->band[0].det = wd3 << 2;
338
339 block4(s, 0, dlow);
340
341 if (s->eight_k)
342 {
343 /* Just leave the high bits as zero */
344 code = (0xC0 | ilow) >> (8 - s->bits_per_sample);
345 }
346 else
347 {
348 /* Block 1H, SUBTRA */
349 eh = saturate(xhigh - s->band[1].s);
350
351 /* Block 1H, QUANTH */
352 wd = (eh >= 0) ? eh : -(eh + 1);
353 wd1 = (564*s->band[1].det) >> 12;
354 mih = (wd >= wd1) ? 2 : 1;
355 ihigh = (eh < 0) ? ihn[mih] : ihp[mih];
356
357 /* Block 2H, INVQAH */
358 wd2 = qm2[ihigh];
359 dhigh = (s->band[1].det*wd2) >> 15;
360
361 /* Block 3H, LOGSCH */
362 ih2 = rh2[ihigh];
363 wd = (s->band[1].nb*127) >> 7;
364 s->band[1].nb = wd + wh[ih2];
365 if (s->band[1].nb < 0)
366 s->band[1].nb = 0;
367 else if (s->band[1].nb > 22528)
368 s->band[1].nb = 22528;
369
370 /* Block 3H, SCALEH */
371 wd1 = (s->band[1].nb >> 6) & 31;
372 wd2 = 10 - (s->band[1].nb >> 11);
373 wd3 = (wd2 < 0) ? (ilb[wd1] << -wd2) : (ilb[wd1] >> wd2);
374 s->band[1].det = wd3 << 2;
375
376 block4(s, 1, dhigh);
377 code = ((ihigh << 6) | ilow) >> (8 - s->bits_per_sample);
378 }
379
380 if (s->packed)
381 {
382 /* Pack the code bits */
383 s->out_buffer |= (code << s->out_bits);
384 s->out_bits += s->bits_per_sample;
385 if (s->out_bits >= 8)
386 {
387 g722_data[g722_bytes++] = (uint8_t) (s->out_buffer & 0xFF);
388 s->out_bits -= 8;
389 s->out_buffer >>= 8;
390 }
391 }
392 else
393 {
394 g722_data[g722_bytes++] = (uint8_t) code;
395 }
396 }
397 return g722_bytes;
398}
399/*- End of function --------------------------------------------------------*/
400/*- End of file ------------------------------------------------------------*/
static EditLine * el
Definition: asterisk.c:340
int int32_t
Definition: db.h:60
short int16_t
Definition: db.h:59
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
@ G722_PACKED
Definition: g722.h:46
@ G722_SAMPLE_RATE_8000
Definition: g722.h:45
#define INT16_MAX
Definition: g722.h:50
#define INT16_MIN
Definition: g722.h:53
int g722_encode_release(g722_encode_state_t *s)
Definition: g722_encode.c:178
static void block4(g722_encode_state_t *s, int band, int d)
Definition: g722_encode.c:63
int g722_encode(g722_encode_state_t *s, uint8_t g722_data[], const int16_t amp[], int len)
Definition: g722_encode.c:185
g722_encode_state_t * g722_encode_init(g722_encode_state_t *s, int rate, int options)
Definition: g722_encode.c:152
#define TRUE
Definition: g722_encode.c:46
#define FALSE
Definition: g722_encode.c:43
static __inline__ int16_t saturate(int32_t amp)
Definition: g722_encode.c:49
char * malloc()
void free()
#define NULL
Definition: resample.c:96
int bits_per_sample
Definition: g722.h:66
unsigned int out_buffer
Definition: g722.h:90
struct g722_encode_state_t::@148 band[2]
int itu_test_mode
Definition: g722.h:60
int x[24]
Definition: g722.h:69
static struct test_options options
static struct test_val d