1 /*
2 * Musepack SV7 decoder
3 * Copyright (c) 2006 Konstantin Shishkov
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 /**
23 * @file
24 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
25 * divided into 32 subbands.
26 */
27
28 #include "libavutil/channel_layout.h"
29 #include "libavutil/internal.h"
30 #include "libavutil/lfg.h"
31 #include "libavutil/mem_internal.h"
32 #include "libavutil/thread.h"
33
34 #include "avcodec.h"
35 #include "codec_internal.h"
36 #include "get_bits.h"
37 #include "internal.h"
38 #include "mpegaudiodsp.h"
39
40 #include "mpc.h"
41 #include "mpc7data.h"
42
43 static VLC scfi_vlc, dscf_vlc, hdr_vlc, quant_vlc[MPC7_QUANT_VLC_TABLES][2];
44
mpc7_init_static(void)45 static av_cold void mpc7_init_static(void)
46 {
47 static VLCElem quant_tables[7224];
48 const uint8_t *raw_quant_table = mpc7_quant_vlcs;
49
50 INIT_VLC_STATIC_FROM_LENGTHS(&scfi_vlc, MPC7_SCFI_BITS, MPC7_SCFI_SIZE,
51 &mpc7_scfi[1], 2,
52 &mpc7_scfi[0], 2, 1, 0, 0, 1 << MPC7_SCFI_BITS);
53 INIT_VLC_STATIC_FROM_LENGTHS(&dscf_vlc, MPC7_DSCF_BITS, MPC7_DSCF_SIZE,
54 &mpc7_dscf[1], 2,
55 &mpc7_dscf[0], 2, 1, -7, 0, 1 << MPC7_DSCF_BITS);
56 INIT_VLC_STATIC_FROM_LENGTHS(&hdr_vlc, MPC7_HDR_BITS, MPC7_HDR_SIZE,
57 &mpc7_hdr[1], 2,
58 &mpc7_hdr[0], 2, 1, -5, 0, 1 << MPC7_HDR_BITS);
59 for (unsigned i = 0, offset = 0; i < MPC7_QUANT_VLC_TABLES; i++){
60 for (int j = 0; j < 2; j++) {
61 quant_vlc[i][j].table = &quant_tables[offset];
62 quant_vlc[i][j].table_allocated = FF_ARRAY_ELEMS(quant_tables) - offset;
63 ff_init_vlc_from_lengths(&quant_vlc[i][j], 9, mpc7_quant_vlc_sizes[i],
64 &raw_quant_table[1], 2,
65 &raw_quant_table[0], 2, 1,
66 mpc7_quant_vlc_off[i],
67 INIT_VLC_STATIC_OVERLONG, NULL);
68 raw_quant_table += 2 * mpc7_quant_vlc_sizes[i];
69 offset += quant_vlc[i][j].table_size;
70 }
71 }
72 ff_mpa_synth_init_fixed();
73 }
74
mpc7_decode_init(AVCodecContext * avctx)75 static av_cold int mpc7_decode_init(AVCodecContext * avctx)
76 {
77 static AVOnce init_static_once = AV_ONCE_INIT;
78 MPCContext *c = avctx->priv_data;
79 GetBitContext gb;
80 LOCAL_ALIGNED_16(uint8_t, buf, [16]);
81
82 /* Musepack SV7 is always stereo */
83 if (avctx->ch_layout.nb_channels != 2) {
84 avpriv_request_sample(avctx, "%d channels", avctx->ch_layout.nb_channels);
85 return AVERROR_PATCHWELCOME;
86 }
87
88 if(avctx->extradata_size < 16){
89 av_log(avctx, AV_LOG_ERROR, "Too small extradata size (%i)!\n", avctx->extradata_size);
90 return AVERROR_INVALIDDATA;
91 }
92 memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
93 av_lfg_init(&c->rnd, 0xDEADBEEF);
94 ff_bswapdsp_init(&c->bdsp);
95 ff_mpadsp_init(&c->mpadsp);
96 c->bdsp.bswap_buf((uint32_t *) buf, (const uint32_t *) avctx->extradata, 4);
97 init_get_bits(&gb, buf, 128);
98
99 c->IS = get_bits1(&gb);
100 c->MSS = get_bits1(&gb);
101 c->maxbands = get_bits(&gb, 6);
102 if(c->maxbands >= BANDS){
103 av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->maxbands);
104 return AVERROR_INVALIDDATA;
105 }
106 skip_bits_long(&gb, 88);
107 c->gapless = get_bits1(&gb);
108 c->lastframelen = get_bits(&gb, 11);
109 av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
110 c->IS, c->MSS, c->gapless, c->lastframelen, c->maxbands);
111 c->frames_to_skip = 0;
112
113 avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
114 av_channel_layout_uninit(&avctx->ch_layout);
115 avctx->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO;
116
117 ff_thread_once(&init_static_once, mpc7_init_static);
118
119 return 0;
120 }
121
122 /**
123 * Fill samples for given subband
124 */
idx_to_quant(MPCContext * c,GetBitContext * gb,int idx,int * dst)125 static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst)
126 {
127 int i, i1, t;
128 switch(idx){
129 case -1:
130 for(i = 0; i < SAMPLES_PER_BAND; i++){
131 *dst++ = (av_lfg_get(&c->rnd) & 0x3FC) - 510;
132 }
133 break;
134 case 1:
135 i1 = get_bits1(gb);
136 for(i = 0; i < SAMPLES_PER_BAND/3; i++){
137 t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2);
138 *dst++ = mpc7_idx30[t];
139 *dst++ = mpc7_idx31[t];
140 *dst++ = mpc7_idx32[t];
141 }
142 break;
143 case 2:
144 i1 = get_bits1(gb);
145 for(i = 0; i < SAMPLES_PER_BAND/2; i++){
146 t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2);
147 *dst++ = mpc7_idx50[t];
148 *dst++ = mpc7_idx51[t];
149 }
150 break;
151 case 3: case 4: case 5: case 6: case 7:
152 i1 = get_bits1(gb);
153 for(i = 0; i < SAMPLES_PER_BAND; i++)
154 *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2);
155 break;
156 case 8: case 9: case 10: case 11: case 12:
157 case 13: case 14: case 15: case 16: case 17:
158 t = (1 << (idx - 2)) - 1;
159 for(i = 0; i < SAMPLES_PER_BAND; i++)
160 *dst++ = get_bits(gb, idx - 1) - t;
161 break;
162 default: // case 0 and -2..-17
163 return;
164 }
165 }
166
get_scale_idx(GetBitContext * gb,int ref)167 static int get_scale_idx(GetBitContext *gb, int ref)
168 {
169 int t = get_vlc2(gb, dscf_vlc.table, MPC7_DSCF_BITS, 1);
170 if (t == 8)
171 return get_bits(gb, 6);
172 return ref + t;
173 }
174
mpc7_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame_ptr,AVPacket * avpkt)175 static int mpc7_decode_frame(AVCodecContext *avctx, AVFrame *frame,
176 int *got_frame_ptr, AVPacket *avpkt)
177 {
178 const uint8_t *buf = avpkt->data;
179 int buf_size;
180 MPCContext *c = avctx->priv_data;
181 GetBitContext gb;
182 int i, ch;
183 int mb = -1;
184 Band *bands = c->bands;
185 int off, ret, last_frame, skip;
186 int bits_used, bits_avail;
187
188 memset(bands, 0, sizeof(*bands) * (c->maxbands + 1));
189
190 buf_size = avpkt->size & ~3;
191 if (buf_size <= 0) {
192 av_log(avctx, AV_LOG_ERROR, "packet size is too small (%i bytes)\n",
193 avpkt->size);
194 return AVERROR_INVALIDDATA;
195 }
196 if (buf_size != avpkt->size) {
197 av_log(avctx, AV_LOG_WARNING, "packet size is not a multiple of 4. "
198 "extra bytes at the end will be skipped.\n");
199 }
200
201 skip = buf[0];
202 last_frame = buf[1];
203 buf += 4;
204 buf_size -= 4;
205
206 /* get output buffer */
207 frame->nb_samples = MPC_FRAME_SIZE;
208 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
209 return ret;
210
211 av_fast_padded_malloc(&c->bits, &c->buf_size, buf_size);
212 if (!c->bits)
213 return AVERROR(ENOMEM);
214 c->bdsp.bswap_buf((uint32_t *) c->bits, (const uint32_t *) buf,
215 buf_size >> 2);
216 if ((ret = init_get_bits8(&gb, c->bits, buf_size)) < 0)
217 return ret;
218 skip_bits_long(&gb, skip);
219
220 /* read subband indexes */
221 for(i = 0; i <= c->maxbands; i++){
222 for(ch = 0; ch < 2; ch++){
223 int t = i ? get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) : 4;
224 if(t == 4) bands[i].res[ch] = get_bits(&gb, 4);
225 else bands[i].res[ch] = bands[i-1].res[ch] + t;
226 if (bands[i].res[ch] < -1 || bands[i].res[ch] > 17) {
227 av_log(avctx, AV_LOG_ERROR, "subband index invalid\n");
228 return AVERROR_INVALIDDATA;
229 }
230 }
231
232 if(bands[i].res[0] || bands[i].res[1]){
233 mb = i;
234 if(c->MSS) bands[i].msf = get_bits1(&gb);
235 }
236 }
237 /* get scale indexes coding method */
238 for(i = 0; i <= mb; i++)
239 for(ch = 0; ch < 2; ch++)
240 if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1);
241 /* get scale indexes */
242 for(i = 0; i <= mb; i++){
243 for(ch = 0; ch < 2; ch++){
244 if(bands[i].res[ch]){
245 bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i];
246 bands[i].scf_idx[ch][0] = get_scale_idx(&gb, bands[i].scf_idx[ch][2]);
247 switch(bands[i].scfi[ch]){
248 case 0:
249 bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]);
250 bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]);
251 break;
252 case 1:
253 bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]);
254 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1];
255 break;
256 case 2:
257 bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
258 bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]);
259 break;
260 case 3:
261 bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
262 break;
263 }
264 c->oldDSCF[ch][i] = bands[i].scf_idx[ch][2];
265 }
266 }
267 }
268 /* get quantizers */
269 memset(c->Q, 0, sizeof(c->Q));
270 off = 0;
271 for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND)
272 for(ch = 0; ch < 2; ch++)
273 idx_to_quant(c, &gb, bands[i].res[ch], c->Q[ch] + off);
274
275 ff_mpc_dequantize_and_synth(c, mb, (int16_t **)frame->extended_data, 2);
276 if(last_frame)
277 frame->nb_samples = c->lastframelen;
278
279 bits_used = get_bits_count(&gb);
280 bits_avail = buf_size * 8;
281 if (!last_frame && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))) {
282 av_log(avctx, AV_LOG_ERROR, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail);
283 return AVERROR_INVALIDDATA;
284 }
285 if(c->frames_to_skip){
286 c->frames_to_skip--;
287 *got_frame_ptr = 0;
288 return avpkt->size;
289 }
290
291 *got_frame_ptr = 1;
292
293 return avpkt->size;
294 }
295
mpc7_decode_flush(AVCodecContext * avctx)296 static void mpc7_decode_flush(AVCodecContext *avctx)
297 {
298 MPCContext *c = avctx->priv_data;
299
300 memset(c->oldDSCF, 0, sizeof(c->oldDSCF));
301 c->frames_to_skip = 32;
302 }
303
mpc7_decode_close(AVCodecContext * avctx)304 static av_cold int mpc7_decode_close(AVCodecContext *avctx)
305 {
306 MPCContext *c = avctx->priv_data;
307 av_freep(&c->bits);
308 c->buf_size = 0;
309 return 0;
310 }
311
312 const FFCodec ff_mpc7_decoder = {
313 .p.name = "mpc7",
314 .p.long_name = NULL_IF_CONFIG_SMALL("Musepack SV7"),
315 .p.type = AVMEDIA_TYPE_AUDIO,
316 .p.id = AV_CODEC_ID_MUSEPACK7,
317 .priv_data_size = sizeof(MPCContext),
318 .init = mpc7_decode_init,
319 .close = mpc7_decode_close,
320 FF_CODEC_DECODE_CB(mpc7_decode_frame),
321 .flush = mpc7_decode_flush,
322 .p.capabilities = AV_CODEC_CAP_DR1,
323 .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
324 AV_SAMPLE_FMT_NONE },
325 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
326 };
327