3 * Copyright (c) 2007-2011 Peter Ross (pross@xvid.org)
4 * Copyright (c) 2009 Daniel Verkamp (daniel@drv.nu)
6 * This file is part of FFmpeg.
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.
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.
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
27 * Technical details here:
28 * http://wiki.multimedia.cx/index.php?title=Bink_Audio
31 #include "libavutil/channel_layout.h"
32 #include "libavutil/intfloat.h"
34 #define BITSTREAM_READER_LE
41 #include "wma_freqs.h"
43 static float quant_table[96];
45 #define MAX_CHANNELS 2
46 #define BINK_BLOCK_MAX_SIZE (MAX_CHANNELS << 11)
48 typedef struct BinkAudioContext {
50 int version_b; ///< Bink version 'b'
53 int frame_len; ///< transform size (samples)
54 int overlap_len; ///< overlap size (samples)
59 DECLARE_ALIGNED(32, FFTSample, coeffs)[BINK_BLOCK_MAX_SIZE];
60 float previous[MAX_CHANNELS][BINK_BLOCK_MAX_SIZE / 16]; ///< coeffs from previous audio block
69 static av_cold int decode_init(AVCodecContext *avctx)
71 BinkAudioContext *s = avctx->priv_data;
72 int sample_rate = avctx->sample_rate;
77 /* determine frame length */
78 if (avctx->sample_rate < 22050) {
80 } else if (avctx->sample_rate < 44100) {
86 if (avctx->channels < 1 || avctx->channels > MAX_CHANNELS) {
87 av_log(avctx, AV_LOG_ERROR, "invalid number of channels: %d\n", avctx->channels);
88 return AVERROR_INVALIDDATA;
90 avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO :
93 s->version_b = avctx->extradata_size >= 4 && avctx->extradata[3] == 'b';
95 if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT) {
96 // audio is already interleaved for the RDFT format variant
97 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
98 if (sample_rate > INT_MAX / avctx->channels)
99 return AVERROR_INVALIDDATA;
100 sample_rate *= avctx->channels;
103 frame_len_bits += av_log2(avctx->channels);
105 s->channels = avctx->channels;
106 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
109 s->frame_len = 1 << frame_len_bits;
110 s->overlap_len = s->frame_len / 16;
111 s->block_size = (s->frame_len - s->overlap_len) * s->channels;
112 sample_rate_half = (sample_rate + 1LL) / 2;
113 if (avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT)
114 s->root = 2.0 / (sqrt(s->frame_len) * 32768.0);
116 s->root = s->frame_len / (sqrt(s->frame_len) * 32768.0);
117 for (i = 0; i < 96; i++) {
118 /* constant is result of 0.066399999/log10(M_E) */
119 quant_table[i] = expf(i * 0.15289164787221953823f) * s->root;
122 /* calculate number of bands */
123 for (s->num_bands = 1; s->num_bands < 25; s->num_bands++)
124 if (sample_rate_half <= ff_wma_critical_freqs[s->num_bands - 1])
127 s->bands = av_malloc((s->num_bands + 1) * sizeof(*s->bands));
129 return AVERROR(ENOMEM);
131 /* populate bands data */
133 for (i = 1; i < s->num_bands; i++)
134 s->bands[i] = (ff_wma_critical_freqs[i - 1] * s->frame_len / sample_rate_half) & ~1;
135 s->bands[s->num_bands] = s->frame_len;
139 if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT)
140 ff_rdft_init(&s->trans.rdft, frame_len_bits, DFT_C2R);
141 else if (CONFIG_BINKAUDIO_DCT_DECODER)
142 ff_dct_init(&s->trans.dct, frame_len_bits, DCT_III);
146 s->pkt = av_packet_alloc();
148 return AVERROR(ENOMEM);
153 static float get_float(GetBitContext *gb)
155 int power = get_bits(gb, 5);
156 float f = ldexpf(get_bits(gb, 23), power - 23);
162 static const uint8_t rle_length_tab[16] = {
163 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 32, 64
167 * Decode Bink Audio block
168 * @param[out] out Output buffer (must contain s->block_size elements)
169 * @return 0 on success, negative error code on failure
171 static int decode_block(BinkAudioContext *s, float **out, int use_dct)
176 GetBitContext *gb = &s->gb;
181 for (ch = 0; ch < s->channels; ch++) {
182 FFTSample *coeffs = out[ch];
185 if (get_bits_left(gb) < 64)
186 return AVERROR_INVALIDDATA;
187 coeffs[0] = av_int2float(get_bits_long(gb, 32)) * s->root;
188 coeffs[1] = av_int2float(get_bits_long(gb, 32)) * s->root;
190 if (get_bits_left(gb) < 58)
191 return AVERROR_INVALIDDATA;
192 coeffs[0] = get_float(gb) * s->root;
193 coeffs[1] = get_float(gb) * s->root;
196 if (get_bits_left(gb) < s->num_bands * 8)
197 return AVERROR_INVALIDDATA;
198 for (i = 0; i < s->num_bands; i++) {
199 int value = get_bits(gb, 8);
200 quant[i] = quant_table[FFMIN(value, 95)];
206 // parse coefficients
208 while (i < s->frame_len) {
212 int v = get_bits1(gb);
215 j = i + rle_length_tab[v] * 8;
221 j = FFMIN(j, s->frame_len);
223 width = get_bits(gb, 4);
225 memset(coeffs + i, 0, (j - i) * sizeof(*coeffs));
227 while (s->bands[k] < i)
231 if (s->bands[k] == i)
233 coeff = get_bits(gb, width);
238 coeffs[i] = -q * coeff;
240 coeffs[i] = q * coeff;
249 if (CONFIG_BINKAUDIO_DCT_DECODER && use_dct) {
251 s->trans.dct.dct_calc(&s->trans.dct, coeffs);
253 else if (CONFIG_BINKAUDIO_RDFT_DECODER)
254 s->trans.rdft.rdft_calc(&s->trans.rdft, coeffs);
257 for (ch = 0; ch < s->channels; ch++) {
259 int count = s->overlap_len * s->channels;
262 for (i = 0; i < s->overlap_len; i++, j += s->channels)
263 out[ch][i] = (s->previous[ch][i] * (count - j) +
264 out[ch][i] * j) / count;
266 memcpy(s->previous[ch], &out[ch][s->frame_len - s->overlap_len],
267 s->overlap_len * sizeof(*s->previous[ch]));
275 static av_cold int decode_end(AVCodecContext *avctx)
277 BinkAudioContext * s = avctx->priv_data;
279 if (CONFIG_BINKAUDIO_RDFT_DECODER && avctx->codec->id == AV_CODEC_ID_BINKAUDIO_RDFT)
280 ff_rdft_end(&s->trans.rdft);
281 else if (CONFIG_BINKAUDIO_DCT_DECODER)
282 ff_dct_end(&s->trans.dct);
284 av_packet_free(&s->pkt);
289 static void get_bits_align32(GetBitContext *s)
291 int n = (-get_bits_count(s)) & 31;
292 if (n) skip_bits(s, n);
295 static int binkaudio_receive_frame(AVCodecContext *avctx, AVFrame *frame)
297 BinkAudioContext *s = avctx->priv_data;
298 GetBitContext *gb = &s->gb;
302 ret = ff_decode_get_packet(avctx, s->pkt);
306 if (s->pkt->size < 4) {
307 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
308 ret = AVERROR_INVALIDDATA;
312 ret = init_get_bits8(gb, s->pkt->data, s->pkt->size);
316 /* skip reported size */
317 skip_bits_long(gb, 32);
320 /* get output buffer */
321 frame->nb_samples = s->frame_len;
322 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
325 if (decode_block(s, (float **)frame->extended_data,
326 avctx->codec->id == AV_CODEC_ID_BINKAUDIO_DCT)) {
327 av_log(avctx, AV_LOG_ERROR, "Incomplete packet\n");
328 return AVERROR_INVALIDDATA;
330 get_bits_align32(gb);
331 if (!get_bits_left(gb)) {
332 memset(gb, 0, sizeof(*gb));
333 av_packet_unref(s->pkt);
336 frame->nb_samples = s->block_size / avctx->channels;
340 av_packet_unref(s->pkt);
344 AVCodec ff_binkaudio_rdft_decoder = {
345 .name = "binkaudio_rdft",
346 .long_name = NULL_IF_CONFIG_SMALL("Bink Audio (RDFT)"),
347 .type = AVMEDIA_TYPE_AUDIO,
348 .id = AV_CODEC_ID_BINKAUDIO_RDFT,
349 .priv_data_size = sizeof(BinkAudioContext),
352 .receive_frame = binkaudio_receive_frame,
353 .capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_DR1,
356 AVCodec ff_binkaudio_dct_decoder = {
357 .name = "binkaudio_dct",
358 .long_name = NULL_IF_CONFIG_SMALL("Bink Audio (DCT)"),
359 .type = AVMEDIA_TYPE_AUDIO,
360 .id = AV_CODEC_ID_BINKAUDIO_DCT,
361 .priv_data_size = sizeof(BinkAudioContext),
364 .receive_frame = binkaudio_receive_frame,
365 .capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_DR1,