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
23 * @file mpc7.c Musepack SV7 decoder
24 * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
25 * divided into 32 subbands.
29 #include "bitstream.h"
33 #ifdef CONFIG_MPEGAUDIO_HP
34 #define USE_HIGHPRECISION
36 #include "mpegaudio.h"
42 #define SAMPLES_PER_BAND 36
43 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND)
45 static VLC scfi_vlc
, dscf_vlc
, hdr_vlc
, quant_vlc
[MPC7_QUANT_VLC_TABLES
][2];
47 static int mpc7_decode_init(AVCodecContext
* avctx
)
50 MPCContext
*c
= avctx
->priv_data
;
53 static int vlc_inited
= 0;
55 if(avctx
->extradata_size
< 16){
56 av_log(avctx
, AV_LOG_ERROR
, "Too small extradata size (%i)!\n", avctx
->extradata_size
);
59 memset(c
->oldDSCF
, 0, sizeof(c
->oldDSCF
));
60 av_init_random(0xDEADBEEF, &c
->rnd
);
61 dsputil_init(&c
->dsp
, avctx
);
62 c
->dsp
.bswap_buf(buf
, avctx
->extradata
, 4);
64 init_get_bits(&gb
, buf
, 128);
66 c
->IS
= get_bits1(&gb
);
67 c
->MSS
= get_bits1(&gb
);
68 c
->maxbands
= get_bits(&gb
, 6);
69 if(c
->maxbands
>= BANDS
){
70 av_log(avctx
, AV_LOG_ERROR
, "Too many bands: %i\n", c
->maxbands
);
74 c
->gapless
= get_bits1(&gb
);
75 c
->lastframelen
= get_bits(&gb
, 11);
76 av_log(avctx
, AV_LOG_DEBUG
, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
77 c
->IS
, c
->MSS
, c
->gapless
, c
->lastframelen
, c
->maxbands
);
78 c
->frames_to_skip
= 0;
80 if(vlc_inited
) return 0;
81 av_log(avctx
, AV_LOG_DEBUG
, "Initing VLC\n");
82 if(init_vlc(&scfi_vlc
, MPC7_SCFI_BITS
, MPC7_SCFI_SIZE
,
84 &mpc7_scfi
[0], 2, 1, INIT_VLC_USE_STATIC
)){
85 av_log(avctx
, AV_LOG_ERROR
, "Cannot init SCFI VLC\n");
88 if(init_vlc(&dscf_vlc
, MPC7_DSCF_BITS
, MPC7_DSCF_SIZE
,
90 &mpc7_dscf
[0], 2, 1, INIT_VLC_USE_STATIC
)){
91 av_log(avctx
, AV_LOG_ERROR
, "Cannot init DSCF VLC\n");
94 if(init_vlc(&hdr_vlc
, MPC7_HDR_BITS
, MPC7_HDR_SIZE
,
96 &mpc7_hdr
[0], 2, 1, INIT_VLC_USE_STATIC
)){
97 av_log(avctx
, AV_LOG_ERROR
, "Cannot init HDR VLC\n");
100 for(i
= 0; i
< MPC7_QUANT_VLC_TABLES
; i
++){
101 for(j
= 0; j
< 2; j
++){
102 if(init_vlc(&quant_vlc
[i
][j
], 9, mpc7_quant_vlc_sizes
[i
],
103 &mpc7_quant_vlc
[i
][j
][1], 4, 2,
104 &mpc7_quant_vlc
[i
][j
][0], 4, 2, INIT_VLC_USE_STATIC
)){
105 av_log(avctx
, AV_LOG_ERROR
, "Cannot init QUANT VLC %i,%i\n",i
,j
);
115 * Fill samples for given subband
117 static inline void idx_to_quant(MPCContext
*c
, GetBitContext
*gb
, int idx
, int *dst
)
122 for(i
= 0; i
< SAMPLES_PER_BAND
; i
++){
123 *dst
++ = (av_random(&c
->rnd
) & 0x3FC) - 510;
128 for(i
= 0; i
< SAMPLES_PER_BAND
/3; i
++){
129 t
= get_vlc2(gb
, quant_vlc
[0][i1
].table
, 9, 2);
130 *dst
++ = mpc7_idx30
[t
];
131 *dst
++ = mpc7_idx31
[t
];
132 *dst
++ = mpc7_idx32
[t
];
137 for(i
= 0; i
< SAMPLES_PER_BAND
/2; i
++){
138 t
= get_vlc2(gb
, quant_vlc
[1][i1
].table
, 9, 2);
139 *dst
++ = mpc7_idx50
[t
];
140 *dst
++ = mpc7_idx51
[t
];
143 case 3: case 4: case 5: case 6: case 7:
145 for(i
= 0; i
< SAMPLES_PER_BAND
; i
++)
146 *dst
++ = get_vlc2(gb
, quant_vlc
[idx
-1][i1
].table
, 9, 2) - mpc7_quant_vlc_off
[idx
-1];
148 case 8: case 9: case 10: case 11: case 12:
149 case 13: case 14: case 15: case 16: case 17:
150 t
= (1 << (idx
- 2)) - 1;
151 for(i
= 0; i
< SAMPLES_PER_BAND
; i
++)
152 *dst
++ = get_bits(gb
, idx
- 1) - t
;
154 default: // case 0 and -2..-17
159 static int mpc7_decode_frame(AVCodecContext
* avctx
,
160 void *data
, int *data_size
,
161 uint8_t * buf
, int buf_size
)
163 MPCContext
*c
= avctx
->priv_data
;
168 Band
*bands
= c
->bands
;
170 int bits_used
, bits_avail
;
172 memset(bands
, 0, sizeof(bands
));
174 av_log(avctx
, AV_LOG_ERROR
, "Too small buffer passed (%i bytes)\n", buf_size
);
177 bits
= av_malloc(((buf_size
- 1) & ~3) + FF_INPUT_BUFFER_PADDING_SIZE
);
178 c
->dsp
.bswap_buf(bits
, buf
+ 4, (buf_size
- 4) >> 2);
179 init_get_bits(&gb
, bits
, (buf_size
- 4)* 8);
180 skip_bits(&gb
, buf
[0]);
182 /* read subband indexes */
183 for(i
= 0; i
<= c
->maxbands
; i
++){
184 for(ch
= 0; ch
< 2; ch
++){
185 if(i
) t
= get_vlc2(&gb
, hdr_vlc
.table
, MPC7_HDR_BITS
, 1) - 5;
186 if(!i
|| (t
== 4)) bands
[i
].res
[ch
] = get_bits(&gb
, 4);
187 else bands
[i
].res
[ch
] = bands
[i
-1].res
[ch
] + t
;
190 if(bands
[i
].res
[0] || bands
[i
].res
[1]){
192 if(c
->MSS
) bands
[i
].msf
= get_bits1(&gb
);
195 /* get scale indexes coding method */
196 for(i
= 0; i
<= mb
; i
++)
197 for(ch
= 0; ch
< 2; ch
++)
198 if(bands
[i
].res
[ch
]) bands
[i
].scfi
[ch
] = get_vlc2(&gb
, scfi_vlc
.table
, MPC7_SCFI_BITS
, 1);
199 /* get scale indexes */
200 for(i
= 0; i
<= mb
; i
++){
201 for(ch
= 0; ch
< 2; ch
++){
202 if(bands
[i
].res
[ch
]){
203 bands
[i
].scf_idx
[ch
][2] = c
->oldDSCF
[ch
][i
];
204 t
= get_vlc2(&gb
, dscf_vlc
.table
, MPC7_DSCF_BITS
, 1) - 7;
205 bands
[i
].scf_idx
[ch
][0] = (t
== 8) ? get_bits(&gb
, 6) : (bands
[i
].scf_idx
[ch
][2] + t
);
206 switch(bands
[i
].scfi
[ch
]){
208 t
= get_vlc2(&gb
, dscf_vlc
.table
, MPC7_DSCF_BITS
, 1) - 7;
209 bands
[i
].scf_idx
[ch
][1] = (t
== 8) ? get_bits(&gb
, 6) : (bands
[i
].scf_idx
[ch
][0] + t
);
210 t
= get_vlc2(&gb
, dscf_vlc
.table
, MPC7_DSCF_BITS
, 1) - 7;
211 bands
[i
].scf_idx
[ch
][2] = (t
== 8) ? get_bits(&gb
, 6) : (bands
[i
].scf_idx
[ch
][1] + t
);
214 t
= get_vlc2(&gb
, dscf_vlc
.table
, MPC7_DSCF_BITS
, 1) - 7;
215 bands
[i
].scf_idx
[ch
][1] = (t
== 8) ? get_bits(&gb
, 6) : (bands
[i
].scf_idx
[ch
][0] + t
);
216 bands
[i
].scf_idx
[ch
][2] = bands
[i
].scf_idx
[ch
][1];
219 bands
[i
].scf_idx
[ch
][1] = bands
[i
].scf_idx
[ch
][0];
220 t
= get_vlc2(&gb
, dscf_vlc
.table
, MPC7_DSCF_BITS
, 1) - 7;
221 bands
[i
].scf_idx
[ch
][2] = (t
== 8) ? get_bits(&gb
, 6) : (bands
[i
].scf_idx
[ch
][1] + t
);
224 bands
[i
].scf_idx
[ch
][2] = bands
[i
].scf_idx
[ch
][1] = bands
[i
].scf_idx
[ch
][0];
227 c
->oldDSCF
[ch
][i
] = bands
[i
].scf_idx
[ch
][2];
232 memset(c
->Q
, 0, sizeof(c
->Q
));
234 for(i
= 0; i
< BANDS
; i
++, off
+= SAMPLES_PER_BAND
)
235 for(ch
= 0; ch
< 2; ch
++)
236 idx_to_quant(c
, &gb
, bands
[i
].res
[ch
], c
->Q
[ch
] + off
);
238 ff_mpc_dequantize_and_synth(c
, mb
, data
);
242 bits_used
= get_bits_count(&gb
);
243 bits_avail
= (buf_size
- 4) * 8;
244 if(!buf
[1] && ((bits_avail
< bits_used
) || (bits_used
+ 32 <= bits_avail
))){
245 av_log(NULL
,0, "Error decoding frame: used %i of %i bits\n", bits_used
, bits_avail
);
248 if(c
->frames_to_skip
){
253 *data_size
= (buf
[1] ? c
->lastframelen
: MPC_FRAME_SIZE
) * 4;
258 static void mpc7_decode_flush(AVCodecContext
*avctx
)
260 MPCContext
*c
= avctx
->priv_data
;
262 memset(c
->oldDSCF
, 0, sizeof(c
->oldDSCF
));
263 c
->frames_to_skip
= 32;
266 AVCodec mpc7_decoder
= {
275 .flush
= mpc7_decode_flush
,