1 /*********************************************************************************
2 ** ITU-T G.722.1 (2005-05) - Fixed point implementation for main body and Annex C
3 ** > Software Release 2.1 (2008-06)
4 ** (Simple repackaging; no change from 2005-05 Release 2.0 code)
5 **
6 ** � 2004 Polycom, Inc.
7 **
8 ** All rights reserved.
9 **
10 *********************************************************************************/
11
12 /*********************************************************************************
13 * Filename: dct_type_iv_a.c
14 *
15 * Purpose: Discrete Cosine Transform, Type IV used for MLT
16 *
17 * The basis functions are
18 *
19 * cos(PI*(t+0.5)*(k+0.5)/block_length)
20 *
21 * for time t and basis function number k. Due to the symmetry of the expression
22 * in t and k, it is clear that the forward and inverse transforms are the same.
23 *
24 *********************************************************************************/
25
26 /*********************************************************************************
27 Include files
28 *********************************************************************************/
29 #include "defs.h"
30 #include "count.h"
31 #include "dct4_a.h"
32
33 /*********************************************************************************
34 External variable declarations
35 *********************************************************************************/
36 extern Word16 anal_bias[DCT_LENGTH];
37 extern Word16 dct_core_a[DCT_LENGTH_DIV_32][DCT_LENGTH_DIV_32];
38 extern cos_msin_t a_cos_msin_2 [DCT_LENGTH_DIV_32];
39 extern cos_msin_t a_cos_msin_4 [DCT_LENGTH_DIV_16];
40 extern cos_msin_t a_cos_msin_8 [DCT_LENGTH_DIV_8];
41 extern cos_msin_t a_cos_msin_16[DCT_LENGTH_DIV_4];
42 extern cos_msin_t a_cos_msin_32[DCT_LENGTH_DIV_2];
43 extern cos_msin_t a_cos_msin_64[DCT_LENGTH];
44 extern cos_msin_t *a_cos_msin_table[];
45
46 /*********************************************************************************
47 Function: dct_type_iv_a
48
49 Syntax: void dct_type_iv_a (input, output, dct_length)
50 Word16 input[], output[], dct_length;
51
52 Description: Discrete Cosine Transform, Type IV used for MLT
53
54 Design Notes:
55
56 WMOPS: | 24kbit | 32kbit
57 -------|--------------|----------------
58 AVG | 1.14 | 1.14
59 -------|--------------|----------------
60 MAX | 1.14 | 1.14
61 -------|--------------|----------------
62
63 14kHz | 24kbit | 32kbit | 48kbit
64 -------|--------------|----------------|----------------
65 AVG | 2.57 | 2.57 | 2.57
66 -------|--------------|----------------|----------------
67 MAX | 2.57 | 2.57 | 2.57
68 -------|--------------|----------------|----------------
69
70 *********************************************************************************/
71
dct_type_iv_a(Word16 * input,Word16 * output,Word16 dct_length)72 void dct_type_iv_a (Word16 *input,Word16 *output,Word16 dct_length)
73 {
74 Word16 buffer_a[MAX_DCT_LENGTH], buffer_b[MAX_DCT_LENGTH], buffer_c[MAX_DCT_LENGTH];
75 Word16 *in_ptr, *in_ptr_low, *in_ptr_high, *next_in_base;
76 Word16 *out_ptr_low, *out_ptr_high, *next_out_base;
77 Word16 *out_buffer, *in_buffer, *buffer_swap;
78 Word16 in_val_low, in_val_high;
79 Word16 out_val_low, out_val_high;
80 Word16 in_low_even, in_low_odd;
81 Word16 in_high_even, in_high_odd;
82 Word16 out_low_even, out_low_odd;
83 Word16 out_high_even, out_high_odd;
84 Word16 *pair_ptr;
85 Word16 cos_even, cos_odd, msin_even, msin_odd;
86 Word16 neg_cos_odd;
87 Word16 neg_msin_even;
88 Word32 sum;
89 Word16 set_span, set_count, set_count_log, pairs_left, sets_left;
90 Word16 i,k;
91 Word16 index;
92 cos_msin_t **table_ptr_ptr, *cos_msin_ptr;
93
94 Word16 temp;
95 Word32 acca;
96
97 Word16 dct_length_log;
98
99
100 /*++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
101 /* Do the sum/difference butterflies, the first part of */
102 /* converting one N-point transform into N/2 two-point */
103 /* transforms, where N = 1 << DCT_LENGTH_LOG. = 64/128 */
104 /*++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
105 test();
106 if (dct_length==DCT_LENGTH)
107 {
108 dct_length_log = DCT_LENGTH_LOG;
109
110 /* Add bias offsets */
111 for (i=0;i<dct_length;i++)
112 {
113 input[i] = add(input[i],anal_bias[i]);
114 move16();
115 }
116 }
117 else
118 dct_length_log = MAX_DCT_LENGTH_LOG;
119
120 index = 0L;
121 move16();
122
123 in_buffer = input;
124 move16();
125
126 out_buffer = buffer_a;
127 move16();
128
129 temp = sub(dct_length_log,2);
130 for (set_count_log=0;set_count_log<=temp;set_count_log++)
131 {
132
133 /*===========================================================*/
134 /* Initialization for the loop over sets at the current size */
135 /*===========================================================*/
136
137 /* set_span = 1 << (DCT_LENGTH_LOG - set_count_log); */
138 set_span = shr(dct_length,set_count_log);
139
140 set_count = shl(1,set_count_log);
141
142 in_ptr = in_buffer;
143 move16();
144
145 next_out_base = out_buffer;
146 move16();
147
148 /*=====================================*/
149 /* Loop over all the sets of this size */
150 /*=====================================*/
151
152 for (sets_left=set_count;sets_left>0;sets_left--)
153 {
154
155 /*||||||||||||||||||||||||||||||||||||||||||||*/
156 /* Set up output pointers for the current set */
157 /*||||||||||||||||||||||||||||||||||||||||||||*/
158
159 out_ptr_low = next_out_base;
160 next_out_base = next_out_base + set_span;
161 out_ptr_high = next_out_base;
162
163 /*||||||||||||||||||||||||||||||||||||||||||||||||||*/
164 /* Loop over all the butterflies in the current set */
165 /*||||||||||||||||||||||||||||||||||||||||||||||||||*/
166
167 do
168 {
169 in_val_low = *in_ptr++;
170 in_val_high = *in_ptr++;
171 acca = L_add(in_val_low,in_val_high);
172 acca = L_shr(acca,1);
173 out_val_low = extract_l(acca);
174
175 acca = L_sub(in_val_low,in_val_high);
176 acca = L_shr(acca,1);
177 out_val_high = extract_l(acca);
178
179 *out_ptr_low++ = out_val_low;
180 *--out_ptr_high = out_val_high;
181
182 test();
183 } while (out_ptr_low < out_ptr_high);
184
185 } /* End of loop over sets of the current size */
186
187 /*============================================================*/
188 /* Decide which buffers to use as input and output next time. */
189 /* Except for the first time (when the input buffer is the */
190 /* subroutine input) we just alternate the local buffers. */
191 /*============================================================*/
192
193 in_buffer = out_buffer;
194 move16();
195 if (out_buffer == buffer_a)
196 out_buffer = buffer_b;
197 else
198 out_buffer = buffer_a;
199 index = add(index,1);
200
201 } /* End of loop over set sizes */
202
203
204 /*++++++++++++++++++++++++++++++++*/
205 /* Do N/2 two-point transforms, */
206 /* where N = 1 << DCT_LENGTH_LOG */
207 /*++++++++++++++++++++++++++++++++*/
208
209 pair_ptr = in_buffer;
210 move16();
211
212 buffer_swap = buffer_c;
213 move16();
214
215 temp = sub(dct_length_log,1);
216 temp = shl(1,temp);
217
218 for (pairs_left=temp; pairs_left > 0; pairs_left--)
219 {
220 for ( k=0; k<CORE_SIZE; k++ )
221 {
222 sum=0L;
223 move32();
224 for ( i=0; i<CORE_SIZE; i++ )
225 {
226 sum = L_mac(sum, pair_ptr[i],dct_core_a[i][k]);
227 }
228 buffer_swap[k] = round(sum);
229 }
230 /* address arithmetic */
231 pair_ptr += CORE_SIZE;
232 buffer_swap += CORE_SIZE;
233 }
234
235 for (i=0;i<dct_length;i++)
236 {
237 in_buffer[i] = buffer_c[i];
238 move16();
239 }
240
241 table_ptr_ptr = a_cos_msin_table;
242
243 /*++++++++++++++++++++++++++++++*/
244 /* Perform rotation butterflies */
245 /*++++++++++++++++++++++++++++++*/
246 temp = sub(dct_length_log,2);
247 for (set_count_log = temp; set_count_log >= 0; set_count_log--)
248 {
249 /*===========================================================*/
250 /* Initialization for the loop over sets at the current size */
251 /*===========================================================*/
252 /* set_span = 1 << (DCT_LENGTH_LOG - set_count_log); */
253 set_span = shr(dct_length,set_count_log);
254
255 set_count = shl(1,set_count_log);
256 next_in_base = in_buffer;
257 move16();
258
259 test();
260 if (set_count_log == 0)
261 {
262 next_out_base = output;
263 }
264 else
265 {
266 next_out_base = out_buffer;
267 }
268
269
270 /*=====================================*/
271 /* Loop over all the sets of this size */
272 /*=====================================*/
273 for (sets_left = set_count; sets_left > 0;sets_left--)
274 {
275 /*|||||||||||||||||||||||||||||||||||||||||*/
276 /* Set up the pointers for the current set */
277 /*|||||||||||||||||||||||||||||||||||||||||*/
278 in_ptr_low = next_in_base;
279 move16();
280 temp = shr(set_span,1);
281
282 /* address arithmetic */
283 in_ptr_high = in_ptr_low + temp;
284 next_in_base += set_span;
285 out_ptr_low = next_out_base;
286 next_out_base += set_span;
287 out_ptr_high = next_out_base;
288 cos_msin_ptr = *table_ptr_ptr;
289
290 /*||||||||||||||||||||||||||||||||||||||||||||||||||||||*/
291 /* Loop over all the butterfly pairs in the current set */
292 /*||||||||||||||||||||||||||||||||||||||||||||||||||||||*/
293
294 do
295 {
296 /* address arithmetic */
297 in_low_even = *in_ptr_low++;
298 in_low_odd = *in_ptr_low++;
299 in_high_even = *in_ptr_high++;
300 in_high_odd = *in_ptr_high++;
301 cos_even = cos_msin_ptr[0].cosine;
302 move16();
303 msin_even = cos_msin_ptr[0].minus_sine;
304 move16();
305 cos_odd = cos_msin_ptr[1].cosine;
306 move16();
307 msin_odd = cos_msin_ptr[1].minus_sine;
308 move16();
309 cos_msin_ptr += 2;
310
311 sum = 0L;
312 sum=L_mac(sum,cos_even,in_low_even);
313 neg_msin_even = negate(msin_even);
314 sum=L_mac(sum,neg_msin_even,in_high_even);
315 out_low_even = round(sum);
316
317 sum = 0L;
318 sum=L_mac(sum,msin_even,in_low_even);
319 sum=L_mac(sum,cos_even,in_high_even);
320 out_high_even= round(sum);
321
322 sum = 0L;
323 sum=L_mac(sum,cos_odd,in_low_odd);
324 sum=L_mac(sum,msin_odd,in_high_odd);
325 out_low_odd= round(sum);
326
327 sum = 0L;
328 sum=L_mac(sum,msin_odd,in_low_odd);
329 neg_cos_odd = negate(cos_odd);
330 sum=L_mac(sum,neg_cos_odd,in_high_odd);
331 out_high_odd= round(sum);
332
333 *out_ptr_low++ = out_low_even;
334 *--out_ptr_high = out_high_even;
335 *out_ptr_low++ = out_low_odd;
336 *--out_ptr_high = out_high_odd;
337 test();
338 } while (out_ptr_low < out_ptr_high);
339
340 } /* End of loop over sets of the current size */
341
342 /*=============================================*/
343 /* Swap input and output buffers for next time */
344 /*=============================================*/
345
346 buffer_swap = in_buffer;
347 in_buffer = out_buffer;
348 out_buffer = buffer_swap;
349 table_ptr_ptr++;
350 }
351 }
352
353