00001 /* 00002 * Musepack SV7 decoder 00003 * Copyright (c) 2006 Konstantin Shishkov 00004 * 00005 * This file is part of FFmpeg. 00006 * 00007 * FFmpeg is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * FFmpeg is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with FFmpeg; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00028 #include "libavutil/lfg.h" 00029 #include "avcodec.h" 00030 #include "get_bits.h" 00031 #include "dsputil.h" 00032 #include "mpegaudiodsp.h" 00033 #include "libavutil/audioconvert.h" 00034 00035 #include "mpc.h" 00036 #include "mpc7data.h" 00037 00038 #define BANDS 32 00039 #define SAMPLES_PER_BAND 36 00040 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND) 00041 00042 static VLC scfi_vlc, dscf_vlc, hdr_vlc, quant_vlc[MPC7_QUANT_VLC_TABLES][2]; 00043 00044 static const uint16_t quant_offsets[MPC7_QUANT_VLC_TABLES*2 + 1] = 00045 { 00046 0, 512, 1024, 1536, 2052, 2564, 3076, 3588, 4100, 4612, 5124, 00047 5636, 6164, 6676, 7224 00048 }; 00049 00050 00051 static av_cold int mpc7_decode_init(AVCodecContext * avctx) 00052 { 00053 int i, j; 00054 MPCContext *c = avctx->priv_data; 00055 GetBitContext gb; 00056 uint8_t buf[16]; 00057 static int vlc_initialized = 0; 00058 00059 static VLC_TYPE scfi_table[1 << MPC7_SCFI_BITS][2]; 00060 static VLC_TYPE dscf_table[1 << MPC7_DSCF_BITS][2]; 00061 static VLC_TYPE hdr_table[1 << MPC7_HDR_BITS][2]; 00062 static VLC_TYPE quant_tables[7224][2]; 00063 00064 /* Musepack SV7 is always stereo */ 00065 if (avctx->channels != 2) { 00066 av_log_ask_for_sample(avctx, "Unsupported number of channels: %d\n", 00067 avctx->channels); 00068 return AVERROR_PATCHWELCOME; 00069 } 00070 00071 if(avctx->extradata_size < 16){ 00072 av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size); 00073 return -1; 00074 } 00075 memset(c->oldDSCF, 0, sizeof(c->oldDSCF)); 00076 av_lfg_init(&c->rnd, 0xDEADBEEF); 00077 dsputil_init(&c->dsp, avctx); 00078 ff_mpadsp_init(&c->mpadsp); 00079 c->dsp.bswap_buf((uint32_t*)buf, (const uint32_t*)avctx->extradata, 4); 00080 ff_mpc_init(); 00081 init_get_bits(&gb, buf, 128); 00082 00083 c->IS = get_bits1(&gb); 00084 c->MSS = get_bits1(&gb); 00085 c->maxbands = get_bits(&gb, 6); 00086 if(c->maxbands >= BANDS){ 00087 av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->maxbands); 00088 return -1; 00089 } 00090 skip_bits_long(&gb, 88); 00091 c->gapless = get_bits1(&gb); 00092 c->lastframelen = get_bits(&gb, 11); 00093 av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n", 00094 c->IS, c->MSS, c->gapless, c->lastframelen, c->maxbands); 00095 c->frames_to_skip = 0; 00096 00097 avctx->sample_fmt = AV_SAMPLE_FMT_S16; 00098 avctx->channel_layout = AV_CH_LAYOUT_STEREO; 00099 00100 if(vlc_initialized) return 0; 00101 av_log(avctx, AV_LOG_DEBUG, "Initing VLC\n"); 00102 scfi_vlc.table = scfi_table; 00103 scfi_vlc.table_allocated = 1 << MPC7_SCFI_BITS; 00104 if(init_vlc(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE, 00105 &mpc7_scfi[1], 2, 1, 00106 &mpc7_scfi[0], 2, 1, INIT_VLC_USE_NEW_STATIC)){ 00107 av_log(avctx, AV_LOG_ERROR, "Cannot init SCFI VLC\n"); 00108 return -1; 00109 } 00110 dscf_vlc.table = dscf_table; 00111 dscf_vlc.table_allocated = 1 << MPC7_DSCF_BITS; 00112 if(init_vlc(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE, 00113 &mpc7_dscf[1], 2, 1, 00114 &mpc7_dscf[0], 2, 1, INIT_VLC_USE_NEW_STATIC)){ 00115 av_log(avctx, AV_LOG_ERROR, "Cannot init DSCF VLC\n"); 00116 return -1; 00117 } 00118 hdr_vlc.table = hdr_table; 00119 hdr_vlc.table_allocated = 1 << MPC7_HDR_BITS; 00120 if(init_vlc(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE, 00121 &mpc7_hdr[1], 2, 1, 00122 &mpc7_hdr[0], 2, 1, INIT_VLC_USE_NEW_STATIC)){ 00123 av_log(avctx, AV_LOG_ERROR, "Cannot init HDR VLC\n"); 00124 return -1; 00125 } 00126 for(i = 0; i < MPC7_QUANT_VLC_TABLES; i++){ 00127 for(j = 0; j < 2; j++){ 00128 quant_vlc[i][j].table = &quant_tables[quant_offsets[i*2 + j]]; 00129 quant_vlc[i][j].table_allocated = quant_offsets[i*2 + j + 1] - quant_offsets[i*2 + j]; 00130 if(init_vlc(&quant_vlc[i][j], 9, mpc7_quant_vlc_sizes[i], 00131 &mpc7_quant_vlc[i][j][1], 4, 2, 00132 &mpc7_quant_vlc[i][j][0], 4, 2, INIT_VLC_USE_NEW_STATIC)){ 00133 av_log(avctx, AV_LOG_ERROR, "Cannot init QUANT VLC %i,%i\n",i,j); 00134 return -1; 00135 } 00136 } 00137 } 00138 vlc_initialized = 1; 00139 00140 avcodec_get_frame_defaults(&c->frame); 00141 avctx->coded_frame = &c->frame; 00142 00143 return 0; 00144 } 00145 00149 static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst) 00150 { 00151 int i, i1, t; 00152 switch(idx){ 00153 case -1: 00154 for(i = 0; i < SAMPLES_PER_BAND; i++){ 00155 *dst++ = (av_lfg_get(&c->rnd) & 0x3FC) - 510; 00156 } 00157 break; 00158 case 1: 00159 i1 = get_bits1(gb); 00160 for(i = 0; i < SAMPLES_PER_BAND/3; i++){ 00161 t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2); 00162 *dst++ = mpc7_idx30[t]; 00163 *dst++ = mpc7_idx31[t]; 00164 *dst++ = mpc7_idx32[t]; 00165 } 00166 break; 00167 case 2: 00168 i1 = get_bits1(gb); 00169 for(i = 0; i < SAMPLES_PER_BAND/2; i++){ 00170 t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2); 00171 *dst++ = mpc7_idx50[t]; 00172 *dst++ = mpc7_idx51[t]; 00173 } 00174 break; 00175 case 3: case 4: case 5: case 6: case 7: 00176 i1 = get_bits1(gb); 00177 for(i = 0; i < SAMPLES_PER_BAND; i++) 00178 *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx-1]; 00179 break; 00180 case 8: case 9: case 10: case 11: case 12: 00181 case 13: case 14: case 15: case 16: case 17: 00182 t = (1 << (idx - 2)) - 1; 00183 for(i = 0; i < SAMPLES_PER_BAND; i++) 00184 *dst++ = get_bits(gb, idx - 1) - t; 00185 break; 00186 default: // case 0 and -2..-17 00187 return; 00188 } 00189 } 00190 00191 static int get_scale_idx(GetBitContext *gb, int ref) 00192 { 00193 int t = get_vlc2(gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7; 00194 if (t == 8) 00195 return get_bits(gb, 6); 00196 return av_clip_uintp2(ref + t, 7); 00197 } 00198 00199 static int mpc7_decode_frame(AVCodecContext * avctx, void *data, 00200 int *got_frame_ptr, AVPacket *avpkt) 00201 { 00202 const uint8_t *buf = avpkt->data; 00203 int buf_size = avpkt->size; 00204 MPCContext *c = avctx->priv_data; 00205 GetBitContext gb; 00206 int i, ch; 00207 int mb = -1; 00208 Band *bands = c->bands; 00209 int off, ret; 00210 int bits_used, bits_avail; 00211 00212 memset(bands, 0, sizeof(*bands) * (c->maxbands + 1)); 00213 if(buf_size <= 4){ 00214 av_log(avctx, AV_LOG_ERROR, "Too small buffer passed (%i bytes)\n", buf_size); 00215 return AVERROR(EINVAL); 00216 } 00217 00218 /* get output buffer */ 00219 c->frame.nb_samples = buf[1] ? c->lastframelen : MPC_FRAME_SIZE; 00220 if ((ret = avctx->get_buffer(avctx, &c->frame)) < 0) { 00221 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 00222 return ret; 00223 } 00224 00225 av_fast_padded_malloc(&c->buffer, &c->buffer_size, FFALIGN(buf_size - 1, 4)); 00226 if (!c->buffer) 00227 return AVERROR(ENOMEM); 00228 c->dsp.bswap_buf((uint32_t*)c->buffer, (const uint32_t*)(buf + 4), (buf_size - 4) >> 2); 00229 init_get_bits(&gb, c->buffer, (buf_size - 4)* 8); 00230 skip_bits_long(&gb, buf[0]); 00231 00232 /* read subband indexes */ 00233 for(i = 0; i <= c->maxbands; i++){ 00234 for(ch = 0; ch < 2; ch++){ 00235 int t = 4; 00236 if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5; 00237 if(t == 4) bands[i].res[ch] = get_bits(&gb, 4); 00238 else bands[i].res[ch] = av_clip(bands[i-1].res[ch] + t, 0, 17); 00239 } 00240 00241 if(bands[i].res[0] || bands[i].res[1]){ 00242 mb = i; 00243 if(c->MSS) bands[i].msf = get_bits1(&gb); 00244 } 00245 } 00246 /* get scale indexes coding method */ 00247 for(i = 0; i <= mb; i++) 00248 for(ch = 0; ch < 2; ch++) 00249 if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1); 00250 /* get scale indexes */ 00251 for(i = 0; i <= mb; i++){ 00252 for(ch = 0; ch < 2; ch++){ 00253 if(bands[i].res[ch]){ 00254 bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i]; 00255 bands[i].scf_idx[ch][0] = get_scale_idx(&gb, bands[i].scf_idx[ch][2]); 00256 switch(bands[i].scfi[ch]){ 00257 case 0: 00258 bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]); 00259 bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]); 00260 break; 00261 case 1: 00262 bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]); 00263 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1]; 00264 break; 00265 case 2: 00266 bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0]; 00267 bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]); 00268 break; 00269 case 3: 00270 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0]; 00271 break; 00272 } 00273 c->oldDSCF[ch][i] = bands[i].scf_idx[ch][2]; 00274 } 00275 } 00276 } 00277 /* get quantizers */ 00278 memset(c->Q, 0, sizeof(c->Q)); 00279 off = 0; 00280 for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND) 00281 for(ch = 0; ch < 2; ch++) 00282 idx_to_quant(c, &gb, bands[i].res[ch], c->Q[ch] + off); 00283 00284 ff_mpc_dequantize_and_synth(c, mb, c->frame.data[0], 2); 00285 00286 bits_used = get_bits_count(&gb); 00287 bits_avail = (buf_size - 4) * 8; 00288 if(!buf[1] && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))){ 00289 av_log(NULL,0, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail); 00290 return -1; 00291 } 00292 if(c->frames_to_skip){ 00293 c->frames_to_skip--; 00294 *got_frame_ptr = 0; 00295 return buf_size; 00296 } 00297 00298 *got_frame_ptr = 1; 00299 *(AVFrame *)data = c->frame; 00300 00301 return buf_size; 00302 } 00303 00304 static void mpc7_decode_flush(AVCodecContext *avctx) 00305 { 00306 MPCContext *c = avctx->priv_data; 00307 00308 memset(c->oldDSCF, 0, sizeof(c->oldDSCF)); 00309 c->frames_to_skip = 32; 00310 } 00311 00312 static av_cold int mpc7_decode_close(AVCodecContext *avctx) 00313 { 00314 MPCContext *c = avctx->priv_data; 00315 av_freep(&c->buffer); 00316 c->buffer_size = 0; 00317 return 0; 00318 } 00319 00320 AVCodec ff_mpc7_decoder = { 00321 .name = "mpc7", 00322 .type = AVMEDIA_TYPE_AUDIO, 00323 .id = CODEC_ID_MUSEPACK7, 00324 .priv_data_size = sizeof(MPCContext), 00325 .init = mpc7_decode_init, 00326 .close = mpc7_decode_close, 00327 .decode = mpc7_decode_frame, 00328 .flush = mpc7_decode_flush, 00329 .capabilities = CODEC_CAP_DR1, 00330 .long_name = NULL_IF_CONFIG_SMALL("Musepack SV7"), 00331 };