1/* 2 * Bink Audio decoder 3 * Copyright (c) 2007-2011 Peter Ross (pross@xvid.org) 4 * Copyright (c) 2009 Daniel Verkamp (daniel@drv.nu) 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 * Bink Audio decoder 26 * 27 * Technical details here: 28 * http://wiki.multimedia.cx/index.php?title=Bink_Audio 29 */ 30 31#include "config_components.h" 32 33#include "libavutil/channel_layout.h" 34#include "libavutil/intfloat.h" 35#include "libavutil/mem_internal.h" 36 37#define BITSTREAM_READER_LE 38#include "avcodec.h" 39#include "dct.h" 40#include "decode.h" 41#include "get_bits.h" 42#include "codec_internal.h" 43#include "internal.h" 44#include "rdft.h" 45#include "wma_freqs.h" 46 47#define MAX_DCT_CHANNELS 6 48#define MAX_CHANNELS 2 49#define BINK_BLOCK_MAX_SIZE (MAX_CHANNELS << 11) 50 51typedef struct BinkAudioContext { 52 GetBitContext gb; 53 int version_b; ///< Bink version 'b' 54 int first; 55 int channels; 56 int ch_offset; 57 int frame_len; ///< transform size (samples) 58 int overlap_len; ///< overlap size (samples) 59 int block_size; 60 int num_bands; 61 float root; 62 unsigned int bands[26]; 63 float previous[MAX_DCT_CHANNELS][BINK_BLOCK_MAX_SIZE / 16]; ///< coeffs from previous audio block 64 float quant_table[96]; 65 AVPacket *pkt; 66 union { 67 RDFTContext rdft; 68 DCTContext dct; 69 } trans; 70} BinkAudioContext; 71 72 73static av_cold int decode_init(AVCodecContext *avctx) 74{ 75 BinkAudioContext *s = avctx->priv_data; 76 int sample_rate = avctx->sample_rate; 77 int sample_rate_half; 78 int i, ret; 79 int frame_len_bits; 80 int max_channels = avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT ? MAX_CHANNELS : MAX_DCT_CHANNELS; 81 int channels = avctx->ch_layout.nb_channels; 82 83 /* determine frame length */ 84 if (avctx->sample_rate < 22050) { 85 frame_len_bits = 9; 86 } else if (avctx->sample_rate < 44100) { 87 frame_len_bits = 10; 88 } else { 89 frame_len_bits = 11; 90 } 91 92 if (channels < 1 || channels > max_channels) { 93 av_log(avctx, AV_LOG_ERROR, "invalid number of channels: %d\n", channels); 94 return AVERROR_INVALIDDATA; 95 } 96 av_channel_layout_uninit(&avctx->ch_layout); 97 av_channel_layout_default(&avctx->ch_layout, channels); 98 99 s->version_b = avctx->extradata_size >= 4 && avctx->extradata[3] == 'b'; 100 101 if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) { 102 // audio is already interleaved for the RDFT format variant 103 avctx->sample_fmt = AV_SAMPLE_FMT_FLT; 104 if (sample_rate > INT_MAX / channels) 105 return AVERROR_INVALIDDATA; 106 sample_rate *= channels; 107 s->channels = 1; 108 if (!s->version_b) 109 frame_len_bits += av_log2(channels); 110 } else { 111 s->channels = channels; 112 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP; 113 } 114 115 s->frame_len = 1 << frame_len_bits; 116 s->overlap_len = s->frame_len / 16; 117 s->block_size = (s->frame_len - s->overlap_len) * FFMIN(MAX_CHANNELS, s->channels); 118 sample_rate_half = (sample_rate + 1LL) / 2; 119 if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) 120 s->root = 2.0 / (sqrt(s->frame_len) * 32768.0); 121 else 122 s->root = s->frame_len / (sqrt(s->frame_len) * 32768.0); 123 for (i = 0; i < 96; i++) { 124 /* constant is result of 0.066399999/log10(M_E) */ 125 s->quant_table[i] = expf(i * 0.15289164787221953823f) * s->root; 126 } 127 128 /* calculate number of bands */ 129 for (s->num_bands = 1; s->num_bands < 25; s->num_bands++) 130 if (sample_rate_half <= ff_wma_critical_freqs[s->num_bands - 1]) 131 break; 132 133 /* populate bands data */ 134 s->bands[0] = 2; 135 for (i = 1; i < s->num_bands; i++) 136 s->bands[i] = (ff_wma_critical_freqs[i - 1] * s->frame_len / sample_rate_half) & ~1; 137 s->bands[s->num_bands] = s->frame_len; 138 139 s->first = 1; 140 141 if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) 142 ret = ff_rdft_init(&s->trans.rdft, frame_len_bits, DFT_C2R); 143 else if (CONFIG_BINKAUDIO_DCT_DECODER) 144 ret = ff_dct_init(&s->trans.dct, frame_len_bits, DCT_III); 145 else 146 av_assert0(0); 147 if (ret < 0) 148 return ret; 149 150 s->pkt = avctx->internal->in_pkt; 151 152 return 0; 153} 154 155static float get_float(GetBitContext *gb) 156{ 157 int power = get_bits(gb, 5); 158 float f = ldexpf(get_bits(gb, 23), power - 23); 159 if (get_bits1(gb)) 160 f = -f; 161 return f; 162} 163 164static const uint8_t rle_length_tab[16] = { 165 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 32, 64 166}; 167 168/** 169 * Decode Bink Audio block 170 * @param[out] out Output buffer (must contain s->block_size elements) 171 * @return 0 on success, negative error code on failure 172 */ 173static int decode_block(BinkAudioContext *s, float **out, int use_dct, 174 int channels, int ch_offset) 175{ 176 int ch, i, j, k; 177 float q, quant[25]; 178 int width, coeff; 179 GetBitContext *gb = &s->gb; 180 181 if (use_dct) 182 skip_bits(gb, 2); 183 184 for (ch = 0; ch < channels; ch++) { 185 FFTSample *coeffs = out[ch + ch_offset]; 186 187 if (s->version_b) { 188 if (get_bits_left(gb) < 64) 189 return AVERROR_INVALIDDATA; 190 coeffs[0] = av_int2float(get_bits_long(gb, 32)) * s->root; 191 coeffs[1] = av_int2float(get_bits_long(gb, 32)) * s->root; 192 } else { 193 if (get_bits_left(gb) < 58) 194 return AVERROR_INVALIDDATA; 195 coeffs[0] = get_float(gb) * s->root; 196 coeffs[1] = get_float(gb) * s->root; 197 } 198 199 if (get_bits_left(gb) < s->num_bands * 8) 200 return AVERROR_INVALIDDATA; 201 for (i = 0; i < s->num_bands; i++) { 202 int value = get_bits(gb, 8); 203 quant[i] = s->quant_table[FFMIN(value, 95)]; 204 } 205 206 k = 0; 207 q = quant[0]; 208 209 // parse coefficients 210 i = 2; 211 while (i < s->frame_len) { 212 if (s->version_b) { 213 j = i + 16; 214 } else { 215 int v = get_bits1(gb); 216 if (v) { 217 v = get_bits(gb, 4); 218 j = i + rle_length_tab[v] * 8; 219 } else { 220 j = i + 8; 221 } 222 } 223 224 j = FFMIN(j, s->frame_len); 225 226 width = get_bits(gb, 4); 227 if (width == 0) { 228 memset(coeffs + i, 0, (j - i) * sizeof(*coeffs)); 229 i = j; 230 while (s->bands[k] < i) 231 q = quant[k++]; 232 } else { 233 while (i < j) { 234 if (s->bands[k] == i) 235 q = quant[k++]; 236 coeff = get_bits(gb, width); 237 if (coeff) { 238 int v; 239 v = get_bits1(gb); 240 if (v) 241 coeffs[i] = -q * coeff; 242 else 243 coeffs[i] = q * coeff; 244 } else { 245 coeffs[i] = 0.0f; 246 } 247 i++; 248 } 249 } 250 } 251 252 if (CONFIG_BINKAUDIO_DCT_DECODER && use_dct) { 253 coeffs[0] /= 0.5; 254 s->trans.dct.dct_calc(&s->trans.dct, coeffs); 255 } 256 else if (CONFIG_BINKAUDIO_RDFT_DECODER) 257 s->trans.rdft.rdft_calc(&s->trans.rdft, coeffs); 258 } 259 260 for (ch = 0; ch < channels; ch++) { 261 int j; 262 int count = s->overlap_len * channels; 263 if (!s->first) { 264 j = ch; 265 for (i = 0; i < s->overlap_len; i++, j += channels) 266 out[ch + ch_offset][i] = (s->previous[ch + ch_offset][i] * (count - j) + 267 out[ch + ch_offset][i] * j) / count; 268 } 269 memcpy(s->previous[ch + ch_offset], &out[ch + ch_offset][s->frame_len - s->overlap_len], 270 s->overlap_len * sizeof(*s->previous[ch + ch_offset])); 271 } 272 273 s->first = 0; 274 275 return 0; 276} 277 278static av_cold int decode_end(AVCodecContext *avctx) 279{ 280 BinkAudioContext * s = avctx->priv_data; 281 if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) 282 ff_rdft_end(&s->trans.rdft); 283 else if (CONFIG_BINKAUDIO_DCT_DECODER) 284 ff_dct_end(&s->trans.dct); 285 286 return 0; 287} 288 289static void get_bits_align32(GetBitContext *s) 290{ 291 int n = (-get_bits_count(s)) & 31; 292 if (n) skip_bits(s, n); 293} 294 295static int binkaudio_receive_frame(AVCodecContext *avctx, AVFrame *frame) 296{ 297 BinkAudioContext *s = avctx->priv_data; 298 GetBitContext *gb = &s->gb; 299 int ret; 300 301again: 302 if (!s->pkt->data) { 303 ret = ff_decode_get_packet(avctx, s->pkt); 304 if (ret < 0) { 305 s->ch_offset = 0; 306 return ret; 307 } 308 309 if (s->pkt->size < 4) { 310 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n"); 311 ret = AVERROR_INVALIDDATA; 312 goto fail; 313 } 314 315 ret = init_get_bits8(gb, s->pkt->data, s->pkt->size); 316 if (ret < 0) 317 goto fail; 318 319 /* skip reported size */ 320 skip_bits_long(gb, 32); 321 } 322 323 /* get output buffer */ 324 if (s->ch_offset == 0) { 325 frame->nb_samples = s->frame_len; 326 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) 327 return ret; 328 } 329 330 if (decode_block(s, (float **)frame->extended_data, 331 avctx->codec->id == AV_CODEC_ID_BINKAUDIO_DCT, 332 FFMIN(MAX_CHANNELS, s->channels - s->ch_offset), s->ch_offset)) { 333 av_log(avctx, AV_LOG_ERROR, "Incomplete packet\n"); 334 s->ch_offset = 0; 335 return AVERROR_INVALIDDATA; 336 } 337 s->ch_offset += MAX_CHANNELS; 338 get_bits_align32(gb); 339 if (!get_bits_left(gb)) { 340 memset(gb, 0, sizeof(*gb)); 341 av_packet_unref(s->pkt); 342 } 343 if (s->ch_offset >= s->channels) { 344 s->ch_offset = 0; 345 } else { 346 goto again; 347 } 348 349 frame->nb_samples = s->block_size / FFMIN(avctx->ch_layout.nb_channels, MAX_CHANNELS); 350 351 return 0; 352fail: 353 s->ch_offset = 0; 354 av_packet_unref(s->pkt); 355 return ret; 356} 357 358static void decode_flush(AVCodecContext *avctx) 359{ 360 BinkAudioContext *const s = avctx->priv_data; 361 362 /* s->pkt coincides with avctx->internal->in_pkt 363 * and is unreferenced generically when flushing. */ 364 s->first = 1; 365 s->ch_offset = 0; 366} 367 368const FFCodec ff_binkaudio_rdft_decoder = { 369 .p.name = "binkaudio_rdft", 370 .p.long_name = NULL_IF_CONFIG_SMALL("Bink Audio (RDFT)"), 371 .p.type = AVMEDIA_TYPE_AUDIO, 372 .p.id = AV_CODEC_ID_BINKAUDIO_RDFT, 373 .priv_data_size = sizeof(BinkAudioContext), 374 .init = decode_init, 375 .flush = decode_flush, 376 .close = decode_end, 377 FF_CODEC_RECEIVE_FRAME_CB(binkaudio_receive_frame), 378 .p.capabilities = AV_CODEC_CAP_DR1, 379 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP, 380}; 381 382const FFCodec ff_binkaudio_dct_decoder = { 383 .p.name = "binkaudio_dct", 384 .p.long_name = NULL_IF_CONFIG_SMALL("Bink Audio (DCT)"), 385 .p.type = AVMEDIA_TYPE_AUDIO, 386 .p.id = AV_CODEC_ID_BINKAUDIO_DCT, 387 .priv_data_size = sizeof(BinkAudioContext), 388 .init = decode_init, 389 .flush = decode_flush, 390 .close = decode_end, 391 FF_CODEC_RECEIVE_FRAME_CB(binkaudio_receive_frame), 392 .p.capabilities = AV_CODEC_CAP_DR1, 393 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP, 394}; 395