3 * Copyright (c) 2007 Konstantin Shishkov
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
25 * divided into 32 subbands.
28 #include "libavutil/lfg.h"
32 #include "mpegaudio.h"
39 static VLC band_vlc, scfi_vlc[2], dscf_vlc[2], res_vlc[2];
40 static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
42 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
43 static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
45 static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
47 int len = mpc8_cnk_len[k-1][n-1] - 1;
48 int code = len ? get_bits_long(gb, len) : 0;
50 if (code >= mpc8_cnk_lost[k-1][n-1])
51 code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
56 static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
59 const uint32_t * C = mpc8_cnk[k-1];
60 int code = mpc8_dec_base(gb, k, n);
75 static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
77 if(mpc8_cnk_len[0][m] < 1) return 0;
78 return mpc8_dec_base(gb, 1, m+1);
81 static int mpc8_get_mask(GetBitContext *gb, int size, int t)
86 mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
87 if((t << 1) > size) mask = ~mask;
92 static const uint16_t vlc_offsets[13] = {
93 0, 640, 1184, 1748, 2298, 2426, 2554, 3066, 3578, 4106, 4618, 5196, 5708
96 static av_cold int mpc8_decode_init(AVCodecContext * avctx)
99 MPCContext *c = avctx->priv_data;
101 static int vlc_initialized = 0;
103 static VLC_TYPE band_table[542][2];
104 static VLC_TYPE q1_table[520][2];
105 static VLC_TYPE q9up_table[524][2];
106 static VLC_TYPE scfi0_table[1 << MPC8_SCFI0_BITS][2];
107 static VLC_TYPE scfi1_table[1 << MPC8_SCFI1_BITS][2];
108 static VLC_TYPE dscf0_table[560][2];
109 static VLC_TYPE dscf1_table[598][2];
110 static VLC_TYPE q3_0_table[512][2];
111 static VLC_TYPE q3_1_table[516][2];
112 static VLC_TYPE codes_table[5708][2];
114 if(avctx->extradata_size < 2){
115 av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
118 memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
119 av_lfg_init(&c->rnd, 0xDEADBEEF);
120 dsputil_init(&c->dsp, avctx);
124 init_get_bits(&gb, avctx->extradata, 16);
126 skip_bits(&gb, 3);//sample rate
127 c->maxbands = get_bits(&gb, 5) + 1;
128 skip_bits(&gb, 4);//channels
129 c->MSS = get_bits1(&gb);
130 c->frames = 1 << (get_bits(&gb, 3) * 2);
132 avctx->sample_fmt = SAMPLE_FMT_S16;
133 avctx->channel_layout = (avctx->channels==2) ? CH_LAYOUT_STEREO : CH_LAYOUT_MONO;
135 if(vlc_initialized) return 0;
136 av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
138 band_vlc.table = band_table;
139 band_vlc.table_allocated = 542;
140 init_vlc(&band_vlc, MPC8_BANDS_BITS, MPC8_BANDS_SIZE,
141 mpc8_bands_bits, 1, 1,
142 mpc8_bands_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
144 q1_vlc.table = q1_table;
145 q1_vlc.table_allocated = 520;
146 init_vlc(&q1_vlc, MPC8_Q1_BITS, MPC8_Q1_SIZE,
148 mpc8_q1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
149 q9up_vlc.table = q9up_table;
150 q9up_vlc.table_allocated = 524;
151 init_vlc(&q9up_vlc, MPC8_Q9UP_BITS, MPC8_Q9UP_SIZE,
152 mpc8_q9up_bits, 1, 1,
153 mpc8_q9up_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
155 scfi_vlc[0].table = scfi0_table;
156 scfi_vlc[0].table_allocated = 1 << MPC8_SCFI0_BITS;
157 init_vlc(&scfi_vlc[0], MPC8_SCFI0_BITS, MPC8_SCFI0_SIZE,
158 mpc8_scfi0_bits, 1, 1,
159 mpc8_scfi0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
160 scfi_vlc[1].table = scfi1_table;
161 scfi_vlc[1].table_allocated = 1 << MPC8_SCFI1_BITS;
162 init_vlc(&scfi_vlc[1], MPC8_SCFI1_BITS, MPC8_SCFI1_SIZE,
163 mpc8_scfi1_bits, 1, 1,
164 mpc8_scfi1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
166 dscf_vlc[0].table = dscf0_table;
167 dscf_vlc[0].table_allocated = 560;
168 init_vlc(&dscf_vlc[0], MPC8_DSCF0_BITS, MPC8_DSCF0_SIZE,
169 mpc8_dscf0_bits, 1, 1,
170 mpc8_dscf0_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
171 dscf_vlc[1].table = dscf1_table;
172 dscf_vlc[1].table_allocated = 598;
173 init_vlc(&dscf_vlc[1], MPC8_DSCF1_BITS, MPC8_DSCF1_SIZE,
174 mpc8_dscf1_bits, 1, 1,
175 mpc8_dscf1_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
177 q3_vlc[0].table = q3_0_table;
178 q3_vlc[0].table_allocated = 512;
179 init_vlc_sparse(&q3_vlc[0], MPC8_Q3_BITS, MPC8_Q3_SIZE,
182 mpc8_q3_syms, 1, 1, INIT_VLC_USE_NEW_STATIC);
183 q3_vlc[1].table = q3_1_table;
184 q3_vlc[1].table_allocated = 516;
185 init_vlc_sparse(&q3_vlc[1], MPC8_Q4_BITS, MPC8_Q4_SIZE,
188 mpc8_q4_syms, 1, 1, INIT_VLC_USE_NEW_STATIC);
190 for(i = 0; i < 2; i++){
191 res_vlc[i].table = &codes_table[vlc_offsets[0+i]];
192 res_vlc[i].table_allocated = vlc_offsets[1+i] - vlc_offsets[0+i];
193 init_vlc(&res_vlc[i], MPC8_RES_BITS, MPC8_RES_SIZE,
194 &mpc8_res_bits[i], 1, 1,
195 &mpc8_res_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
197 q2_vlc[i].table = &codes_table[vlc_offsets[2+i]];
198 q2_vlc[i].table_allocated = vlc_offsets[3+i] - vlc_offsets[2+i];
199 init_vlc(&q2_vlc[i], MPC8_Q2_BITS, MPC8_Q2_SIZE,
200 &mpc8_q2_bits[i], 1, 1,
201 &mpc8_q2_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
203 quant_vlc[0][i].table = &codes_table[vlc_offsets[4+i]];
204 quant_vlc[0][i].table_allocated = vlc_offsets[5+i] - vlc_offsets[4+i];
205 init_vlc(&quant_vlc[0][i], MPC8_Q5_BITS, MPC8_Q5_SIZE,
206 &mpc8_q5_bits[i], 1, 1,
207 &mpc8_q5_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
208 quant_vlc[1][i].table = &codes_table[vlc_offsets[6+i]];
209 quant_vlc[1][i].table_allocated = vlc_offsets[7+i] - vlc_offsets[6+i];
210 init_vlc(&quant_vlc[1][i], MPC8_Q6_BITS, MPC8_Q6_SIZE,
211 &mpc8_q6_bits[i], 1, 1,
212 &mpc8_q6_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
213 quant_vlc[2][i].table = &codes_table[vlc_offsets[8+i]];
214 quant_vlc[2][i].table_allocated = vlc_offsets[9+i] - vlc_offsets[8+i];
215 init_vlc(&quant_vlc[2][i], MPC8_Q7_BITS, MPC8_Q7_SIZE,
216 &mpc8_q7_bits[i], 1, 1,
217 &mpc8_q7_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
218 quant_vlc[3][i].table = &codes_table[vlc_offsets[10+i]];
219 quant_vlc[3][i].table_allocated = vlc_offsets[11+i] - vlc_offsets[10+i];
220 init_vlc(&quant_vlc[3][i], MPC8_Q8_BITS, MPC8_Q8_SIZE,
221 &mpc8_q8_bits[i], 1, 1,
222 &mpc8_q8_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
228 static int mpc8_decode_frame(AVCodecContext * avctx,
229 void *data, int *data_size,
232 const uint8_t *buf = avpkt->data;
233 int buf_size = avpkt->size;
234 MPCContext *c = avctx->priv_data;
235 GetBitContext gb2, *gb = &gb2;
236 int i, j, k, ch, cnt, res, t;
237 Band *bands = c->bands;
239 int maxband, keyframe;
242 keyframe = c->cur_frame == 0;
245 memset(c->Q, 0, sizeof(c->Q));
246 c->last_bits_used = 0;
248 init_get_bits(gb, buf, buf_size * 8);
249 skip_bits(gb, c->last_bits_used & 7);
252 maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
254 maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
255 if(maxband > 32) maxband -= 33;
257 c->last_max_band = maxband;
259 /* read subband indexes */
261 last[0] = last[1] = 0;
262 for(i = maxband - 1; i >= 0; i--){
263 for(ch = 0; ch < 2; ch++){
264 last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
265 if(last[ch] > 15) last[ch] -= 17;
266 bands[i].res[ch] = last[ch];
273 for(i = 0; i < maxband; i++)
274 if(bands[i].res[0] || bands[i].res[1])
276 t = mpc8_get_mod_golomb(gb, cnt);
277 mask = mpc8_get_mask(gb, cnt, t);
278 for(i = maxband - 1; i >= 0; i--)
279 if(bands[i].res[0] || bands[i].res[1]){
280 bands[i].msf = mask & 1;
285 for(i = maxband; i < c->maxbands; i++)
286 bands[i].res[0] = bands[i].res[1] = 0;
289 for(i = 0; i < 32; i++)
290 c->oldDSCF[0][i] = c->oldDSCF[1][i] = 1;
293 for(i = 0; i < maxband; i++){
294 if(bands[i].res[0] || bands[i].res[1]){
295 cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
297 t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
298 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
299 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
304 for(i = 0; i < maxband; i++){
305 for(ch = 0; ch < 2; ch++){
306 if(!bands[i].res[ch]) continue;
308 if(c->oldDSCF[ch][i]){
309 bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
310 c->oldDSCF[ch][i] = 0;
312 t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
314 t += get_bits(gb, 6);
315 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
317 for(j = 0; j < 2; j++){
318 if((bands[i].scfi[ch] << j) & 2)
319 bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
321 t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
323 t = 64 + get_bits(gb, 6);
324 bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
330 for(i = 0, off = 0; i < maxband; i++, off += SAMPLES_PER_BAND){
331 for(ch = 0; ch < 2; ch++){
332 res = bands[i].res[ch];
335 for(j = 0; j < SAMPLES_PER_BAND; j++)
336 c->Q[ch][off + j] = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
341 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
342 cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
343 t = mpc8_get_mask(gb, 18, cnt);
344 for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
345 c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
349 cnt = 6;//2*mpc8_thres[res]
350 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
351 t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
352 c->Q[ch][off + j + 0] = mpc8_idx50[t];
353 c->Q[ch][off + j + 1] = mpc8_idx51[t];
354 c->Q[ch][off + j + 2] = mpc8_idx52[t];
355 cnt = (cnt >> 1) + mpc8_huffq2[t];
360 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
361 t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
362 c->Q[ch][off + j + 1] = t >> 4;
363 c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
370 cnt = 2 * mpc8_thres[res];
371 for(j = 0; j < SAMPLES_PER_BAND; j++){
372 t = get_vlc2(gb, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
373 c->Q[ch][off + j] = t;
374 cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
378 for(j = 0; j < SAMPLES_PER_BAND; j++){
379 c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
381 c->Q[ch][off + j] <<= res - 9;
382 c->Q[ch][off + j] |= get_bits(gb, res - 9);
384 c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
390 ff_mpc_dequantize_and_synth(c, maxband, data);
394 c->last_bits_used = get_bits_count(gb);
395 if(c->cur_frame >= c->frames)
397 *data_size = MPC_FRAME_SIZE * 4;
399 return c->cur_frame ? c->last_bits_used >> 3 : buf_size;
402 AVCodec mpc8_decoder = {
411 .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),