Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / ralf.c
1 /*
2 * RealAudio Lossless decoder
3 *
4 * Copyright (c) 2012 Konstantin Shishkov
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 /**
24 * @file
25 * This is a decoder for Real Audio Lossless format.
26 * Dedicated to the mastermind behind it, Ralph Wiggum.
27 */
28
29 #include "libavutil/attributes.h"
30 #include "libavutil/channel_layout.h"
31 #include "avcodec.h"
32 #include "get_bits.h"
33 #include "golomb.h"
34 #include "internal.h"
35 #include "unary.h"
36 #include "ralfdata.h"
37
38 #define FILTER_NONE 0
39 #define FILTER_RAW 642
40
41 typedef struct VLCSet {
42 VLC filter_params;
43 VLC bias;
44 VLC coding_mode;
45 VLC filter_coeffs[10][11];
46 VLC short_codes[15];
47 VLC long_codes[125];
48 } VLCSet;
49
50 #define RALF_MAX_PKT_SIZE 8192
51
52 typedef struct RALFContext {
53 int version;
54 int max_frame_size;
55 VLCSet sets[3];
56 int32_t channel_data[2][4096];
57
58 int filter_params; ///< combined filter parameters for the current channel data
59 int filter_length; ///< length of the filter for the current channel data
60 int filter_bits; ///< filter precision for the current channel data
61 int32_t filter[64];
62
63 int bias[2]; ///< a constant value added to channel data after filtering
64
65 int num_blocks; ///< number of blocks inside the frame
66 int sample_offset;
67 int block_size[1 << 12]; ///< size of the blocks
68 int block_pts[1 << 12]; ///< block start time (in milliseconds)
69
70 uint8_t pkt[16384];
71 int has_pkt;
72 } RALFContext;
73
74 #define MAX_ELEMS 644 // no RALF table uses more than that
75
76 static av_cold int init_ralf_vlc(VLC *vlc, const uint8_t *data, int elems)
77 {
78 uint8_t lens[MAX_ELEMS];
79 uint16_t codes[MAX_ELEMS];
80 int counts[17], prefixes[18];
81 int i, cur_len;
82 int max_bits = 0;
83 int nb = 0;
84
85 for (i = 0; i <= 16; i++)
86 counts[i] = 0;
87 for (i = 0; i < elems; i++) {
88 cur_len = (nb ? *data & 0xF : *data >> 4) + 1;
89 counts[cur_len]++;
90 max_bits = FFMAX(max_bits, cur_len);
91 lens[i] = cur_len;
92 data += nb;
93 nb ^= 1;
94 }
95 prefixes[1] = 0;
96 for (i = 1; i <= 16; i++)
97 prefixes[i + 1] = (prefixes[i] + counts[i]) << 1;
98
99 for (i = 0; i < elems; i++)
100 codes[i] = prefixes[lens[i]]++;
101
102 return ff_init_vlc_sparse(vlc, FFMIN(max_bits, 9), elems,
103 lens, 1, 1, codes, 2, 2, NULL, 0, 0, 0);
104 }
105
106 static av_cold int decode_close(AVCodecContext *avctx)
107 {
108 RALFContext *ctx = avctx->priv_data;
109 int i, j, k;
110
111 for (i = 0; i < 3; i++) {
112 ff_free_vlc(&ctx->sets[i].filter_params);
113 ff_free_vlc(&ctx->sets[i].bias);
114 ff_free_vlc(&ctx->sets[i].coding_mode);
115 for (j = 0; j < 10; j++)
116 for (k = 0; k < 11; k++)
117 ff_free_vlc(&ctx->sets[i].filter_coeffs[j][k]);
118 for (j = 0; j < 15; j++)
119 ff_free_vlc(&ctx->sets[i].short_codes[j]);
120 for (j = 0; j < 125; j++)
121 ff_free_vlc(&ctx->sets[i].long_codes[j]);
122 }
123
124 return 0;
125 }
126
127 static av_cold int decode_init(AVCodecContext *avctx)
128 {
129 RALFContext *ctx = avctx->priv_data;
130 int i, j, k;
131 int ret;
132
133 if (avctx->extradata_size < 24 || memcmp(avctx->extradata, "LSD:", 4)) {
134 av_log(avctx, AV_LOG_ERROR, "Extradata is not groovy, dude\n");
135 return AVERROR_INVALIDDATA;
136 }
137
138 ctx->version = AV_RB16(avctx->extradata + 4);
139 if (ctx->version != 0x103) {
140 avpriv_request_sample(avctx, "Unknown version %X", ctx->version);
141 return AVERROR_PATCHWELCOME;
142 }
143
144 avctx->channels = AV_RB16(avctx->extradata + 8);
145 avctx->sample_rate = AV_RB32(avctx->extradata + 12);
146 if (avctx->channels < 1 || avctx->channels > 2
147 || avctx->sample_rate < 8000 || avctx->sample_rate > 96000) {
148 av_log(avctx, AV_LOG_ERROR, "Invalid coding parameters %d Hz %d ch\n",
149 avctx->sample_rate, avctx->channels);
150 return AVERROR_INVALIDDATA;
151 }
152 avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
153 avctx->channel_layout = (avctx->channels == 2) ? AV_CH_LAYOUT_STEREO
154 : AV_CH_LAYOUT_MONO;
155
156 ctx->max_frame_size = AV_RB32(avctx->extradata + 16);
157 if (ctx->max_frame_size > (1 << 20) || !ctx->max_frame_size) {
158 av_log(avctx, AV_LOG_ERROR, "invalid frame size %d\n",
159 ctx->max_frame_size);
160 }
161 ctx->max_frame_size = FFMAX(ctx->max_frame_size, avctx->sample_rate);
162
163 for (i = 0; i < 3; i++) {
164 ret = init_ralf_vlc(&ctx->sets[i].filter_params, filter_param_def[i],
165 FILTERPARAM_ELEMENTS);
166 if (ret < 0) {
167 decode_close(avctx);
168 return ret;
169 }
170 ret = init_ralf_vlc(&ctx->sets[i].bias, bias_def[i], BIAS_ELEMENTS);
171 if (ret < 0) {
172 decode_close(avctx);
173 return ret;
174 }
175 ret = init_ralf_vlc(&ctx->sets[i].coding_mode, coding_mode_def[i],
176 CODING_MODE_ELEMENTS);
177 if (ret < 0) {
178 decode_close(avctx);
179 return ret;
180 }
181 for (j = 0; j < 10; j++) {
182 for (k = 0; k < 11; k++) {
183 ret = init_ralf_vlc(&ctx->sets[i].filter_coeffs[j][k],
184 filter_coeffs_def[i][j][k],
185 FILTER_COEFFS_ELEMENTS);
186 if (ret < 0) {
187 decode_close(avctx);
188 return ret;
189 }
190 }
191 }
192 for (j = 0; j < 15; j++) {
193 ret = init_ralf_vlc(&ctx->sets[i].short_codes[j],
194 short_codes_def[i][j], SHORT_CODES_ELEMENTS);
195 if (ret < 0) {
196 decode_close(avctx);
197 return ret;
198 }
199 }
200 for (j = 0; j < 125; j++) {
201 ret = init_ralf_vlc(&ctx->sets[i].long_codes[j],
202 long_codes_def[i][j], LONG_CODES_ELEMENTS);
203 if (ret < 0) {
204 decode_close(avctx);
205 return ret;
206 }
207 }
208 }
209
210 return 0;
211 }
212
213 static inline int extend_code(GetBitContext *gb, int val, int range, int bits)
214 {
215 if (val == 0) {
216 val = -range - get_ue_golomb(gb);
217 } else if (val == range * 2) {
218 val = range + get_ue_golomb(gb);
219 } else {
220 val -= range;
221 }
222 if (bits)
223 val = (val << bits) | get_bits(gb, bits);
224 return val;
225 }
226
227 static int decode_channel(RALFContext *ctx, GetBitContext *gb, int ch,
228 int length, int mode, int bits)
229 {
230 int i, t;
231 int code_params;
232 VLCSet *set = ctx->sets + mode;
233 VLC *code_vlc; int range, range2, add_bits;
234 int *dst = ctx->channel_data[ch];
235
236 ctx->filter_params = get_vlc2(gb, set->filter_params.table, 9, 2);
237 ctx->filter_bits = (ctx->filter_params - 2) >> 6;
238 ctx->filter_length = ctx->filter_params - (ctx->filter_bits << 6) - 1;
239
240 if (ctx->filter_params == FILTER_RAW) {
241 for (i = 0; i < length; i++)
242 dst[i] = get_bits(gb, bits);
243 ctx->bias[ch] = 0;
244 return 0;
245 }
246
247 ctx->bias[ch] = get_vlc2(gb, set->bias.table, 9, 2);
248 ctx->bias[ch] = extend_code(gb, ctx->bias[ch], 127, 4);
249
250 if (ctx->filter_params == FILTER_NONE) {
251 memset(dst, 0, sizeof(*dst) * length);
252 return 0;
253 }
254
255 if (ctx->filter_params > 1) {
256 int cmode = 0, coeff = 0;
257 VLC *vlc = set->filter_coeffs[ctx->filter_bits] + 5;
258
259 add_bits = ctx->filter_bits;
260
261 for (i = 0; i < ctx->filter_length; i++) {
262 t = get_vlc2(gb, vlc[cmode].table, vlc[cmode].bits, 2);
263 t = extend_code(gb, t, 21, add_bits);
264 if (!cmode)
265 coeff -= 12 << add_bits;
266 coeff = t - coeff;
267 ctx->filter[i] = coeff;
268
269 cmode = coeff >> add_bits;
270 if (cmode < 0) {
271 cmode = -1 - av_log2(-cmode);
272 if (cmode < -5)
273 cmode = -5;
274 } else if (cmode > 0) {
275 cmode = 1 + av_log2(cmode);
276 if (cmode > 5)
277 cmode = 5;
278 }
279 }
280 }
281
282 code_params = get_vlc2(gb, set->coding_mode.table, set->coding_mode.bits, 2);
283 if (code_params >= 15) {
284 add_bits = av_clip((code_params / 5 - 3) / 2, 0, 10);
285 if (add_bits > 9 && (code_params % 5) != 2)
286 add_bits--;
287 range = 10;
288 range2 = 21;
289 code_vlc = set->long_codes + code_params - 15;
290 } else {
291 add_bits = 0;
292 range = 6;
293 range2 = 13;
294 code_vlc = set->short_codes + code_params;
295 }
296
297 for (i = 0; i < length; i += 2) {
298 int code1, code2;
299
300 t = get_vlc2(gb, code_vlc->table, code_vlc->bits, 2);
301 code1 = t / range2;
302 code2 = t % range2;
303 dst[i] = extend_code(gb, code1, range, 0) << add_bits;
304 dst[i + 1] = extend_code(gb, code2, range, 0) << add_bits;
305 if (add_bits) {
306 dst[i] |= get_bits(gb, add_bits);
307 dst[i + 1] |= get_bits(gb, add_bits);
308 }
309 }
310
311 return 0;
312 }
313
314 static void apply_lpc(RALFContext *ctx, int ch, int length, int bits)
315 {
316 int i, j, acc;
317 int *audio = ctx->channel_data[ch];
318 int bias = 1 << (ctx->filter_bits - 1);
319 int max_clip = (1 << bits) - 1, min_clip = -max_clip - 1;
320
321 for (i = 1; i < length; i++) {
322 int flen = FFMIN(ctx->filter_length, i);
323
324 acc = 0;
325 for (j = 0; j < flen; j++)
326 acc += ctx->filter[j] * audio[i - j - 1];
327 if (acc < 0) {
328 acc = (acc + bias - 1) >> ctx->filter_bits;
329 acc = FFMAX(acc, min_clip);
330 } else {
331 acc = (acc + bias) >> ctx->filter_bits;
332 acc = FFMIN(acc, max_clip);
333 }
334 audio[i] += acc;
335 }
336 }
337
338 static int decode_block(AVCodecContext *avctx, GetBitContext *gb,
339 int16_t *dst0, int16_t *dst1)
340 {
341 RALFContext *ctx = avctx->priv_data;
342 int len, ch, ret;
343 int dmode, mode[2], bits[2];
344 int *ch0, *ch1;
345 int i, t, t2;
346
347 len = 12 - get_unary(gb, 0, 6);
348
349 if (len <= 7) len ^= 1; // codes for length = 6 and 7 are swapped
350 len = 1 << len;
351
352 if (ctx->sample_offset + len > ctx->max_frame_size) {
353 av_log(avctx, AV_LOG_ERROR,
354 "Decoder's stomach is crying, it ate too many samples\n");
355 return AVERROR_INVALIDDATA;
356 }
357
358 if (avctx->channels > 1)
359 dmode = get_bits(gb, 2) + 1;
360 else
361 dmode = 0;
362
363 mode[0] = (dmode == 4) ? 1 : 0;
364 mode[1] = (dmode >= 2) ? 2 : 0;
365 bits[0] = 16;
366 bits[1] = (mode[1] == 2) ? 17 : 16;
367
368 for (ch = 0; ch < avctx->channels; ch++) {
369 if ((ret = decode_channel(ctx, gb, ch, len, mode[ch], bits[ch])) < 0)
370 return ret;
371 if (ctx->filter_params > 1 && ctx->filter_params != FILTER_RAW) {
372 ctx->filter_bits += 3;
373 apply_lpc(ctx, ch, len, bits[ch]);
374 }
375 if (get_bits_left(gb) < 0)
376 return AVERROR_INVALIDDATA;
377 }
378 ch0 = ctx->channel_data[0];
379 ch1 = ctx->channel_data[1];
380 switch (dmode) {
381 case 0:
382 for (i = 0; i < len; i++)
383 dst0[i] = ch0[i] + ctx->bias[0];
384 break;
385 case 1:
386 for (i = 0; i < len; i++) {
387 dst0[i] = ch0[i] + ctx->bias[0];
388 dst1[i] = ch1[i] + ctx->bias[1];
389 }
390 break;
391 case 2:
392 for (i = 0; i < len; i++) {
393 ch0[i] += ctx->bias[0];
394 dst0[i] = ch0[i];
395 dst1[i] = ch0[i] - (ch1[i] + ctx->bias[1]);
396 }
397 break;
398 case 3:
399 for (i = 0; i < len; i++) {
400 t = ch0[i] + ctx->bias[0];
401 t2 = ch1[i] + ctx->bias[1];
402 dst0[i] = t + t2;
403 dst1[i] = t;
404 }
405 break;
406 case 4:
407 for (i = 0; i < len; i++) {
408 t = ch1[i] + ctx->bias[1];
409 t2 = ((ch0[i] + ctx->bias[0]) << 1) | (t & 1);
410 dst0[i] = (t2 + t) / 2;
411 dst1[i] = (t2 - t) / 2;
412 }
413 break;
414 }
415
416 ctx->sample_offset += len;
417
418 return 0;
419 }
420
421 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
422 AVPacket *avpkt)
423 {
424 RALFContext *ctx = avctx->priv_data;
425 AVFrame *frame = data;
426 int16_t *samples0;
427 int16_t *samples1;
428 int ret;
429 GetBitContext gb;
430 int table_size, table_bytes, i;
431 const uint8_t *src, *block_pointer;
432 int src_size;
433 int bytes_left;
434
435 if (ctx->has_pkt) {
436 ctx->has_pkt = 0;
437 table_bytes = (AV_RB16(avpkt->data) + 7) >> 3;
438 if (table_bytes + 3 > avpkt->size || avpkt->size > RALF_MAX_PKT_SIZE) {
439 av_log(avctx, AV_LOG_ERROR, "Wrong packet's breath smells of wrong data!\n");
440 return AVERROR_INVALIDDATA;
441 }
442 if (memcmp(ctx->pkt, avpkt->data, 2 + table_bytes)) {
443 av_log(avctx, AV_LOG_ERROR, "Wrong packet tails are wrong!\n");
444 return AVERROR_INVALIDDATA;
445 }
446
447 src = ctx->pkt;
448 src_size = RALF_MAX_PKT_SIZE + avpkt->size;
449 memcpy(ctx->pkt + RALF_MAX_PKT_SIZE, avpkt->data + 2 + table_bytes,
450 avpkt->size - 2 - table_bytes);
451 } else {
452 if (avpkt->size == RALF_MAX_PKT_SIZE) {
453 memcpy(ctx->pkt, avpkt->data, avpkt->size);
454 ctx->has_pkt = 1;
455 *got_frame_ptr = 0;
456
457 return avpkt->size;
458 }
459 src = avpkt->data;
460 src_size = avpkt->size;
461 }
462
463 frame->nb_samples = ctx->max_frame_size;
464 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
465 return ret;
466 samples0 = (int16_t *)frame->data[0];
467 samples1 = (int16_t *)frame->data[1];
468
469 if (src_size < 5) {
470 av_log(avctx, AV_LOG_ERROR, "too short packets are too short!\n");
471 return AVERROR_INVALIDDATA;
472 }
473 table_size = AV_RB16(src);
474 table_bytes = (table_size + 7) >> 3;
475 if (src_size < table_bytes + 3) {
476 av_log(avctx, AV_LOG_ERROR, "short packets are short!\n");
477 return AVERROR_INVALIDDATA;
478 }
479 init_get_bits(&gb, src + 2, table_size);
480 ctx->num_blocks = 0;
481 while (get_bits_left(&gb) > 0) {
482 ctx->block_size[ctx->num_blocks] = get_bits(&gb, 15);
483 if (get_bits1(&gb)) {
484 ctx->block_pts[ctx->num_blocks] = get_bits(&gb, 9);
485 } else {
486 ctx->block_pts[ctx->num_blocks] = 0;
487 }
488 ctx->num_blocks++;
489 }
490
491 block_pointer = src + table_bytes + 2;
492 bytes_left = src_size - table_bytes - 2;
493 ctx->sample_offset = 0;
494 for (i = 0; i < ctx->num_blocks; i++) {
495 if (bytes_left < ctx->block_size[i]) {
496 av_log(avctx, AV_LOG_ERROR, "I'm pedaling backwards\n");
497 break;
498 }
499 init_get_bits(&gb, block_pointer, ctx->block_size[i] * 8);
500 if (decode_block(avctx, &gb, samples0 + ctx->sample_offset,
501 samples1 + ctx->sample_offset) < 0) {
502 av_log(avctx, AV_LOG_ERROR, "Sir, I got carsick in your office. Not decoding the rest of packet.\n");
503 break;
504 }
505 block_pointer += ctx->block_size[i];
506 bytes_left -= ctx->block_size[i];
507 }
508
509 frame->nb_samples = ctx->sample_offset;
510 *got_frame_ptr = ctx->sample_offset > 0;
511
512 return avpkt->size;
513 }
514
515 static void decode_flush(AVCodecContext *avctx)
516 {
517 RALFContext *ctx = avctx->priv_data;
518
519 ctx->has_pkt = 0;
520 }
521
522
523 AVCodec ff_ralf_decoder = {
524 .name = "ralf",
525 .long_name = NULL_IF_CONFIG_SMALL("RealAudio Lossless"),
526 .type = AVMEDIA_TYPE_AUDIO,
527 .id = AV_CODEC_ID_RALF,
528 .priv_data_size = sizeof(RALFContext),
529 .init = decode_init,
530 .close = decode_close,
531 .decode = decode_frame,
532 .flush = decode_flush,
533 .capabilities = CODEC_CAP_DR1,
534 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
535 AV_SAMPLE_FMT_NONE },
536 };