3 * Copyright (c) 2006 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 * @file mpc.c Musepack decoder
25 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
26 * divided into 32 subbands.
30 #include "bitstream.h"
33 #ifdef CONFIG_MPEGAUDIO_HP
34 #define USE_HIGHPRECISION
36 #include "mpegaudio.h"
41 #define SAMPLES_PER_BAND 36
42 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND)
44 static VLC scfi_vlc, dscf_vlc, hdr_vlc, quant_vlc[MPC7_QUANT_VLC_TABLES][2];
46 static DECLARE_ALIGNED_16(MPA_INT, mpa_window[512]);
51 int lastframelen, bands;
52 int oldDSCF[2][BANDS];
56 DECLARE_ALIGNED_16(MPA_INT, synth_buf[MPA_MAX_CHANNELS][512*2]);
57 int synth_buf_offset[MPA_MAX_CHANNELS];
58 DECLARE_ALIGNED_16(int32_t, sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT]);
61 /** Subband structure - hold all variables for each subband */
63 int msf; ///< mid-stereo flag
70 static int mpc7_decode_init(AVCodecContext * avctx)
73 MPCContext *c = avctx->priv_data;
76 float f1=1.20050805774840750476 * 256;
77 static int vlc_inited = 0;
79 if(avctx->extradata_size < 16){
80 av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
83 memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
85 dsputil_init(&c->dsp, avctx);
86 c->dsp.bswap_buf(buf, avctx->extradata, 4);
87 ff_mpa_synth_init(mpa_window);
88 init_get_bits(&gb, buf, 128);
90 c->IS = get_bits1(&gb);
91 c->MSS = get_bits1(&gb);
92 c->bands = get_bits(&gb, 6);
93 if(c->bands >= BANDS){
94 av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->bands);
98 c->gapless = get_bits1(&gb);
99 c->lastframelen = get_bits(&gb, 11);
100 av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
101 c->IS, c->MSS, c->gapless, c->lastframelen, c->bands);
102 c->frames_to_skip = 0;
104 if(vlc_inited) return 0;
105 av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n");
106 if(init_vlc(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE,
108 &mpc7_scfi[0], 2, 1, INIT_VLC_USE_STATIC)){
109 av_log(avctx, AV_LOG_ERROR, "Cannot init SCFI VLC\n");
112 if(init_vlc(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE,
114 &mpc7_dscf[0], 2, 1, INIT_VLC_USE_STATIC)){
115 av_log(avctx, AV_LOG_ERROR, "Cannot init DSCF VLC\n");
118 if(init_vlc(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE,
120 &mpc7_hdr[0], 2, 1, INIT_VLC_USE_STATIC)){
121 av_log(avctx, AV_LOG_ERROR, "Cannot init HDR VLC\n");
124 for(i = 0; i < MPC7_QUANT_VLC_TABLES; i++){
125 for(j = 0; j < 2; j++){
126 if(init_vlc(&quant_vlc[i][j], 9, mpc7_quant_vlc_sizes[i],
127 &mpc7_quant_vlc[i][j][1], 4, 2,
128 &mpc7_quant_vlc[i][j][0], 4, 2, INIT_VLC_USE_STATIC)){
129 av_log(avctx, AV_LOG_ERROR, "Cannot init QUANT VLC %i,%i\n",i,j);
138 // XXX replace with something better
139 static int av_always_inline mpc_rnd(MPCContext *c)
141 c->rnd = c->rnd * 27 + 17;
146 * Process decoded Musepack data and produce PCM
147 * @todo make it available for MPC8 and MPC6
149 static void mpc_synth(MPCContext *c, int16_t *out)
151 int dither_state = 0;
153 OUT_INT samples[MPA_MAX_CHANNELS * MPA_FRAME_SIZE], *samples_ptr;
155 for(ch = 0; ch < 2; ch++){
156 samples_ptr = samples + ch;
157 for(i = 0; i < SAMPLES_PER_BAND; i++) {
158 ff_mpa_synth_filter(c->synth_buf[ch], &(c->synth_buf_offset[ch]),
159 mpa_window, &dither_state,
161 c->sb_samples[ch][i]);
165 for(i = 0; i < MPC_FRAME_SIZE*2; i++)
170 * Fill samples for given subband
172 static void inline idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst)
177 for(i = 0; i < SAMPLES_PER_BAND; i++){
179 *dst++ = ((t>>24)& 0xFF) + ((t>>16) & 0xFF) + ((t>>8) & 0xFF) + (t & 0xFF) - 510;
183 for(i = 0; i < SAMPLES_PER_BAND/3; i++){
184 t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2);
185 *dst++ = mpc_idx30[t];
186 *dst++ = mpc_idx31[t];
187 *dst++ = mpc_idx32[t];
192 for(i = 0; i < SAMPLES_PER_BAND/2; i++){
193 t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2);
194 *dst++ = mpc_idx50[t];
195 *dst++ = mpc_idx51[t];
198 case 3: case 4: case 5: case 6: case 7:
200 for(i = 0; i < SAMPLES_PER_BAND; i++)
201 *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx-1];
203 case 8: case 9: case 10: case 11: case 12:
204 case 13: case 14: case 15: case 16: case 17:
205 t = (1 << (idx - 2)) - 1;
206 for(i = 0; i < SAMPLES_PER_BAND; i++)
207 *dst++ = get_bits(gb, idx - 1) - t;
209 default: // case 0 and -2..-17
214 static int mpc7_decode_frame(AVCodecContext * avctx,
215 void *data, int *data_size,
216 uint8_t * buf, int buf_size)
218 MPCContext *c = avctx->priv_data;
224 int Q[2][MPC_FRAME_SIZE];
227 int bits_used, bits_avail;
229 memset(bands, 0, sizeof(bands));
231 av_log(avctx, AV_LOG_ERROR, "Too small buffer passed (%i bytes)\n", buf_size);
234 bits = av_malloc((buf_size - 1) & ~3);
235 c->dsp.bswap_buf(bits, buf + 4, (buf_size - 4) >> 2);
236 init_get_bits(&gb, bits, (buf_size - 4)* 8);
237 skip_bits(&gb, buf[0]);
239 /* read subband indexes */
240 for(i = 0; i <= c->bands; i++){
241 for(ch = 0; ch < 2; ch++){
242 if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5;
243 if(!i || (t == 4)) bands[i].res[ch] = get_bits(&gb, 4);
244 else bands[i].res[ch] = bands[i-1].res[ch] + t;
247 if(bands[i].res[0] || bands[i].res[1]){
249 if(c->MSS) bands[i].msf = get_bits1(&gb);
252 /* get scale indexes coding method */
253 for(i = 0; i <= mb; i++)
254 for(ch = 0; ch < 2; ch++)
255 if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1);
256 /* get scale indexes */
257 for(i = 0; i <= mb; i++){
258 for(ch = 0; ch < 2; ch++){
259 if(bands[i].res[ch]){
260 bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i];
261 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
262 bands[i].scf_idx[ch][0] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][2] + t);
263 switch(bands[i].scfi[ch]){
265 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
266 bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
267 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
268 bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
271 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
272 bands[i].scf_idx[ch][1] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][0] + t);
273 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1];
276 bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
277 t = get_vlc2(&gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
278 bands[i].scf_idx[ch][2] = (t == 8) ? get_bits(&gb, 6) : (bands[i].scf_idx[ch][1] + t);
281 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
284 c->oldDSCF[ch][i] = bands[i].scf_idx[ch][2];
289 memset(Q, 0, sizeof(Q));
291 for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND)
292 for(ch = 0; ch < 2; ch++)
293 idx_to_quant(c, &gb, bands[i].res[ch], Q[ch] + off);
295 memset(c->sb_samples, 0, sizeof(c->sb_samples));
297 for(i = 0; i <= mb; i++, off += SAMPLES_PER_BAND){
298 for(ch = 0; ch < 2; ch++){
299 if(bands[i].res[ch]){
301 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][0]];
303 c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
304 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][1]];
306 c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
307 mul = mpc_CC[bands[i].res[ch]] * mpc7_SCF[bands[i].scf_idx[ch][2]];
309 c->sb_samples[ch][j][i] = mul * Q[ch][j + off];
314 for(j = 0; j < SAMPLES_PER_BAND; j++){
315 t1 = c->sb_samples[0][j][i];
316 t2 = c->sb_samples[1][j][i];
317 c->sb_samples[0][j][i] = t1 + t2;
318 c->sb_samples[1][j][i] = t1 - t2;
327 bits_used = get_bits_count(&gb);
328 bits_avail = (buf_size - 4) * 8;
329 if(!buf[1] && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))){
330 av_log(NULL,0, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail);
333 if(c->frames_to_skip){
338 *data_size = (buf[1] ? c->lastframelen : MPC_FRAME_SIZE) * 4;
343 static void mpc7_decode_flush(AVCodecContext *avctx)
345 MPCContext *c = avctx->priv_data;
347 memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
348 c->frames_to_skip = 32;
351 AVCodec mpc7_decoder = {
360 .flush = mpc7_decode_flush,