Move the *-1 to a more sane place as well.
[libav.git] / libavcodec / nellymoserdec.c
CommitLineData
636b13c5
BL
1/*
2 * NellyMoser audio decoder
3 * Copyright (c) 2007 a840bda5870ba11f19698ff6eb9581dfb0f95fa5,
4 * 539459aeb7d425140b62a3ec7dbf6dc8e408a306, and
5 * 520e17cd55896441042b14df2566a6eb610ed444
6 * Copyright (c) 2007 Loic Minier <lool at dooz.org>
7 * Benjamin Larsson
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the "Software"),
11 * to deal in the Software without restriction, including without limitation
12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13 * and/or sell copies of the Software, and to permit persons to whom the
14 * Software is furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25 * DEALINGS IN THE SOFTWARE.
26 */
27
28/**
29 * @file nellymoserdec.c
30 * The 3 alphanumeric copyright notices are md5summed they are from the original
31 * implementors. The original code is available from http://code.google.com/p/nelly2pcm/
32 */
33#include "avcodec.h"
34#include "random.h"
35#include "dsputil.h"
36
37#define ALT_BITSTREAM_READER_LE
38#include "bitstream.h"
39
40#define NELLY_BANDS 23
41#define NELLY_BLOCK_LEN 64
42#define NELLY_HEADER_BITS 116
43#define NELLY_DETAIL_BITS 198
44#define NELLY_BUF_LEN 128
45#define NELLY_FILL_LEN 124
46#define NELLY_BIT_CAP 6
47#define NELLY_BASE_OFF 4228
48#define NELLY_BASE_SHIFT 19
eb1c687b 49#define NELLY_SAMPLES (2 * NELLY_BUF_LEN)
636b13c5
BL
50
51static const float dequantization_table[127] = {
520.0000000000,-0.8472560048, 0.7224709988, -1.5247479677, -0.4531480074, 0.3753609955, 1.4717899561,
53-1.9822579622, -1.1929379702, -0.5829370022, -0.0693780035, 0.3909569979,0.9069200158, 1.4862740040,
54 2.2215409279, -2.3887870312, -1.8067539930, -1.4105420113, -1.0773609877, -0.7995010018,-0.5558109879,
55-0.3334020078, -0.1324490011, 0.0568020009, 0.2548770010, 0.4773550034, 0.7386850119, 1.0443060398,
561.3954459429, 1.8098750114, 2.3918759823,-2.3893830776, -1.9884680510, -1.7514040470, -1.5643119812,
57-1.3922129869,-1.2164649963, -1.0469499826, -0.8905100226, -0.7645580173, -0.6454579830, -0.5259280205,
58-0.4059549868, -0.3029719889, -0.2096900046, -0.1239869967, -0.0479229987, 0.0257730000, 0.1001340002,
590.1737180054, 0.2585540116, 0.3522900045, 0.4569880068, 0.5767750144, 0.7003160119, 0.8425520062,
601.0093879700, 1.1821349859, 1.3534560204, 1.5320819616, 1.7332619429, 1.9722349644, 2.3978140354,
61-2.5756309032, -2.0573320389, -1.8984919786, -1.7727810144, -1.6662600040, -1.5742180347, -1.4993319511,
62-1.4316639900, -1.3652280569, -1.3000990152, -1.2280930281, -1.1588579416, -1.0921250582, -1.0135740042,
63-0.9202849865, -0.8287050128, -0.7374889851, -0.6447759867, -0.5590940118, -0.4857139885, -0.4110319912,
64-0.3459700048, -0.2851159871, -0.2341620028, -0.1870580018, -0.1442500055, -0.1107169986, -0.0739680007,
65-0.0365610011, -0.0073290002, 0.0203610007, 0.0479039997, 0.0751969963, 0.0980999991, 0.1220389977,
660.1458999962, 0.1694349945, 0.1970459968, 0.2252430022, 0.2556869984, 0.2870100141, 0.3197099864,
670.3525829911, 0.3889069855, 0.4334920049, 0.4769459963, 0.5204820037, 0.5644530058, 0.6122040153,
680.6685929894, 0.7341650128, 0.8032159805, 0.8784040213, 0.9566209912, 1.0397069454, 1.1293770075,
691.2211159468, 1.3080279827, 1.4024800062, 1.5056819916, 1.6227730513, 1.7724959850, 1.9430880547,
70 2.2903931141
71};
72
73static const uint8_t nelly_band_sizes_table[NELLY_BANDS] = {
742, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 5, 6, 6, 7, 8, 9, 10, 12, 14, 15
75};
76
77static const uint16_t nelly_init_table[64] = {
783134, 5342, 6870, 7792, 8569, 9185, 9744, 10191, 10631, 11061, 11434, 11770,
7912116, 12513, 12925, 13300, 13674, 14027, 14352, 14716, 15117, 15477, 15824,
8016157, 16513, 16804, 17090, 17401, 17679, 17948, 18238, 18520, 18764, 19078,
8119381, 19640, 19921, 20205, 20500, 20813, 21162, 21465, 21794, 22137, 22453,
8222756, 23067, 23350, 23636, 23926, 24227, 24521, 24819, 25107, 25414, 25730,
8326120, 26497, 26895, 27344, 27877, 28463, 29426, 31355
84};
85
86static const int16_t nelly_delta_table[32] = {
87-11725, -9420, -7910, -6801, -5948, -5233, -4599, -4039, -3507, -3030, -2596,
88-2170, -1774, -1383, -1016, -660, -329, -1, 337, 696, 1085, 1512, 1962, 2433,
892968, 3569, 4314, 5279, 6622, 8154, 10076, 12975
90};
91
92typedef struct NellyMoserDecodeContext {
93 AVCodecContext* avctx;
ff4b050a 94 DECLARE_ALIGNED_16(float,float_buf[NELLY_SAMPLES]);
5c656605 95 float state[128];
636b13c5
BL
96 AVRandomState random_state;
97 GetBitContext gb;
98 int add_bias;
5d32325a 99 float scale_bias;
636b13c5 100 DSPContext dsp;
eb1c687b
FB
101 MDCTContext imdct_ctx;
102 DECLARE_ALIGNED_16(float,imdct_tmp[NELLY_BUF_LEN]);
103 DECLARE_ALIGNED_16(float,imdct_out[NELLY_BUF_LEN * 2]);
636b13c5
BL
104} NellyMoserDecodeContext;
105
b64fa5b4 106static DECLARE_ALIGNED_16(float,sine_window[128]);
636b13c5
BL
107
108static inline int signed_shift(int i, int shift) {
109 if (shift > 0)
110 return i << shift;
111 return i >> -shift;
112}
113
e616c6d6
MN
114
115static void overlap_and_window(NellyMoserDecodeContext *s, float *state, float *audio, float *a_in)
636b13c5 116{
e616c6d6 117 int bot, top, top2;
636b13c5
BL
118
119 bot = 0;
120 top = NELLY_BUF_LEN-1;
636b13c5 121
687550d3 122 while (bot < NELLY_BUF_LEN) {
5d32325a 123 audio[bot] = a_in[bot]*sine_window[bot]+state[bot]*sine_window[top] + s->add_bias;
636b13c5
BL
124
125 bot++;
636b13c5
BL
126 top--;
127 }
5c656605 128 memcpy(state, a_in + NELLY_BUF_LEN, sizeof(float)*NELLY_BUF_LEN);
636b13c5
BL
129}
130
131static int sum_bits(short *buf, short shift, short off)
132{
133 int b, i = 0, ret = 0;
134
135 for (i = 0; i < NELLY_FILL_LEN; i++) {
136 b = buf[i]-off;
137 b = ((b>>(shift-1))+1)>>1;
138 ret += av_clip(b, 0, NELLY_BIT_CAP);
139 }
140
141 return ret;
142}
143
144static int headroom(int *la)
145{
146 int l;
147 if (*la == 0) {
148 return 31;
149 }
150 l = 30 - av_log2(FFABS(*la));
151 *la <<= l;
152 return l;
153}
154
155
eb1c687b 156static void get_sample_bits(const float *buf, int *bits)
636b13c5
BL
157{
158 int i, j;
159 short sbuf[128];
160 int bitsum = 0, last_bitsum, small_bitsum, big_bitsum;
161 short shift, shift_saved;
162 int max, sum, last_off, tmp;
163 int big_off, small_off;
164 int off;
165
166 max = 0;
167 for (i = 0; i < NELLY_FILL_LEN; i++) {
168 max = FFMAX(max, buf[i]);
169 }
170 shift = -16;
171 shift += headroom(&max);
172
173 sum = 0;
174 for (i = 0; i < NELLY_FILL_LEN; i++) {
175 sbuf[i] = signed_shift(buf[i], shift);
176 sbuf[i] = (3*sbuf[i])>>2;
177 sum += sbuf[i];
178 }
179
180 shift += 11;
181 shift_saved = shift;
182 sum -= NELLY_DETAIL_BITS << shift;
183 shift += headroom(&sum);
184 small_off = (NELLY_BASE_OFF * (sum>>16)) >> 15;
185 shift = shift_saved - (NELLY_BASE_SHIFT+shift-31);
186
187 small_off = signed_shift(small_off, shift);
188
189 bitsum = sum_bits(sbuf, shift_saved, small_off);
190
191 if (bitsum != NELLY_DETAIL_BITS) {
192 shift = 0;
193 off = bitsum - NELLY_DETAIL_BITS;
194
195 for(shift=0; FFABS(off) <= 16383; shift++)
196 off *= 2;
197
198 off = (off * NELLY_BASE_OFF) >> 15;
199 shift = shift_saved-(NELLY_BASE_SHIFT+shift-15);
200
201 off = signed_shift(off, shift);
202
203 for (j = 1; j < 20; j++) {
204 last_off = small_off;
205 small_off += off;
206 last_bitsum = bitsum;
207
208 bitsum = sum_bits(sbuf, shift_saved, small_off);
209
210 if ((bitsum-NELLY_DETAIL_BITS) * (last_bitsum-NELLY_DETAIL_BITS) <= 0)
211 break;
212 }
213
214 if (bitsum > NELLY_DETAIL_BITS) {
215 big_off = small_off;
216 small_off = last_off;
217 big_bitsum=bitsum;
218 small_bitsum=last_bitsum;
219 } else {
220 big_off = last_off;
221 big_bitsum=last_bitsum;
222 small_bitsum=bitsum;
223 }
224
225 while (bitsum != NELLY_DETAIL_BITS && j <= 19) {
226 off = (big_off+small_off)>>1;
227 bitsum = sum_bits(sbuf, shift_saved, off);
228 if (bitsum > NELLY_DETAIL_BITS) {
229 big_off=off;
230 big_bitsum=bitsum;
231 } else {
232 small_off = off;
233 small_bitsum=bitsum;
234 }
235 j++;
236 }
237
238 if (abs(big_bitsum-NELLY_DETAIL_BITS) >=
239 abs(small_bitsum-NELLY_DETAIL_BITS)) {
240 bitsum = small_bitsum;
241 } else {
242 small_off = big_off;
243 bitsum = big_bitsum;
244 }
245 }
246
247 for (i = 0; i < NELLY_FILL_LEN; i++) {
248 tmp = sbuf[i]-small_off;
249 tmp = ((tmp>>(shift_saved-1))+1)>>1;
250 bits[i] = av_clip(tmp, 0, NELLY_BIT_CAP);
251 }
252
253 if (bitsum > NELLY_DETAIL_BITS) {
254 tmp = i = 0;
255 while (tmp < NELLY_DETAIL_BITS) {
256 tmp += bits[i];
257 i++;
258 }
259
260 bits[i-1] -= tmp - NELLY_DETAIL_BITS;
261 for(; i < NELLY_FILL_LEN; i++)
262 bits[i] = 0;
263 }
264}
265
7993df65 266void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
636b13c5
BL
267{
268 int i,j;
eb1c687b 269 float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
636b13c5
BL
270 float *aptr, *bptr, *pptr, val, pval;
271 int bits[NELLY_BUF_LEN];
272 unsigned char v;
273
274 init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
275
276 bptr = buf;
277 pptr = pows;
278 val = nelly_init_table[get_bits(&s->gb, 6)];
279 for (i=0 ; i<NELLY_BANDS ; i++) {
280 if (i > 0)
281 val += nelly_delta_table[get_bits(&s->gb, 5)];
a1b914b2 282 pval = -pow(2, val/2048) * s->scale_bias;
636b13c5
BL
283 for (j = 0; j < nelly_band_sizes_table[i]; j++) {
284 *bptr++ = val;
285 *pptr++ = pval;
286 }
287
288 }
289
636b13c5
BL
290 get_sample_bits(buf, bits);
291
292 for (i = 0; i < 2; i++) {
eb1c687b
FB
293 aptr = audio + i * NELLY_BUF_LEN;
294
636b13c5
BL
295 init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
296 skip_bits(&s->gb, NELLY_HEADER_BITS + i*NELLY_DETAIL_BITS);
297
298 for (j = 0; j < NELLY_FILL_LEN; j++) {
299 if (bits[j] <= 0) {
eb1c687b 300 aptr[j] = M_SQRT1_2*pows[j];
a1b914b2 301 if (av_random(&s->random_state) & 1)
eb1c687b 302 aptr[j] *= -1.0;
636b13c5
BL
303 } else {
304 v = get_bits(&s->gb, bits[j]);
a1b914b2 305 aptr[j] = dequantization_table[(1<<bits[j])-1+v]*pows[j];
636b13c5
BL
306 }
307 }
eb1c687b
FB
308 memset(&aptr[NELLY_FILL_LEN], 0,
309 (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
310
311 s->imdct_ctx.fft.imdct_calc(&s->imdct_ctx, s->imdct_out,
312 aptr, s->imdct_tmp);
313 /* XXX: overlapping and windowing should be part of a more
314 generic imdct function */
e616c6d6 315 overlap_and_window(s, s->state, aptr, s->imdct_out);
636b13c5
BL
316 }
317}
318
98a6fff9 319static av_cold int decode_init(AVCodecContext * avctx) {
636b13c5
BL
320 NellyMoserDecodeContext *s = avctx->priv_data;
321 int i;
636b13c5
BL
322
323 s->avctx = avctx;
324 av_init_random(0, &s->random_state);
eb1c687b
FB
325 ff_mdct_init(&s->imdct_ctx, 8, 1);
326
636b13c5
BL
327 dsputil_init(&s->dsp, avctx);
328
329 if(s->dsp.float_to_int16 == ff_float_to_int16_c) {
330 s->add_bias = 385;
5d32325a 331 s->scale_bias = 1.0/(8*32768);
636b13c5
BL
332 } else {
333 s->add_bias = 0;
5d32325a 334 s->scale_bias = 1.0/(1*8);
636b13c5
BL
335 }
336
337 /* Generate overlap window */
338 if (!sine_window[0])
339 for (i=0 ; i<128; i++) {
340 sine_window[i] = sin((i + 0.5) / 256.0 * M_PI);
341 }
342
636b13c5
BL
343 return 0;
344}
345
346static int decode_tag(AVCodecContext * avctx,
347 void *data, int *data_size,
7993df65 348 const uint8_t * buf, int buf_size) {
636b13c5
BL
349 NellyMoserDecodeContext *s = avctx->priv_data;
350 int blocks, i;
351 int16_t* samples;
352 *data_size = 0;
353 samples = (int16_t*)data;
354
355 if (buf_size < avctx->block_align)
356 return buf_size;
357
358 switch (buf_size) {
359 case 64: // 8000Hz
360 blocks = 1; break;
361 case 128: // 11025Hz
362 blocks = 2; break;
363 case 256: // 22050Hz
364 blocks = 4; break;
8e1b957c
AB
365 case 512: // 44100Hz
366 blocks = 8; break;
636b13c5 367 default:
8ef4de4e 368 av_log(avctx, AV_LOG_ERROR, "Tag size %d unknown, report sample!\n", buf_size);
636b13c5
BL
369 return buf_size;
370 }
371
372 for (i=0 ; i<blocks ; i++) {
373 nelly_decode_block(s, &buf[i*NELLY_BLOCK_LEN], s->float_buf);
374 s->dsp.float_to_int16(&samples[i*NELLY_SAMPLES], s->float_buf, NELLY_SAMPLES);
375 *data_size += NELLY_SAMPLES*sizeof(int16_t);
376 }
377
5b0b5ecf 378 return buf_size;
636b13c5
BL
379}
380
98a6fff9 381static av_cold int decode_end(AVCodecContext * avctx) {
636b13c5
BL
382 NellyMoserDecodeContext *s = avctx->priv_data;
383
eb1c687b 384 ff_mdct_end(&s->imdct_ctx);
636b13c5
BL
385 return 0;
386}
387
388AVCodec nellymoser_decoder = {
389 "nellymoser",
390 CODEC_TYPE_AUDIO,
391 CODEC_ID_NELLYMOSER,
392 sizeof(NellyMoserDecodeContext),
393 decode_init,
394 NULL,
395 decode_end,
396 decode_tag,
397};
398