3 * Copyright (c) 2002-2007 The FFmpeg Project.
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
29 /* XXX: use same run/length optimization as mpeg decoders */
30 //FIXME maybe split decode / encode or pass flag
31 static void init_coef_vlc(VLC
*vlc
,
32 uint16_t **prun_table
, uint16_t **plevel_table
, uint16_t **pint_table
,
33 const CoefVLCTable
*vlc_table
)
36 const uint8_t *table_bits
= vlc_table
->huffbits
;
37 const uint32_t *table_codes
= vlc_table
->huffcodes
;
38 const uint16_t *levels_table
= vlc_table
->levels
;
39 uint16_t *run_table
, *level_table
, *int_table
;
40 int i
, l
, j
, k
, level
;
42 init_vlc(vlc
, VLCBITS
, n
, table_bits
, 1, 1, table_codes
, 4, 4, 0);
44 run_table
= av_malloc(n
* sizeof(uint16_t));
45 level_table
= av_malloc(n
* sizeof(uint16_t));
46 int_table
= av_malloc(n
* sizeof(uint16_t));
52 l
= levels_table
[k
++];
55 level_table
[i
] = level
;
60 *prun_table
= run_table
;
61 *plevel_table
= level_table
;
62 *pint_table
= int_table
;
65 int ff_wma_init(AVCodecContext
* avctx
, int flags2
)
67 WMACodecContext
*s
= avctx
->priv_data
;
69 float bps1
, high_freq
;
74 if( avctx
->sample_rate
<=0 || avctx
->sample_rate
>50000
75 || avctx
->channels
<=0 || avctx
->channels
>8
76 || avctx
->bit_rate
<=0)
79 s
->sample_rate
= avctx
->sample_rate
;
80 s
->nb_channels
= avctx
->channels
;
81 s
->bit_rate
= avctx
->bit_rate
;
82 s
->block_align
= avctx
->block_align
;
84 dsputil_init(&s
->dsp
, avctx
);
86 if (avctx
->codec
->id
== CODEC_ID_WMAV1
) {
92 /* compute MDCT block size */
93 if (s
->sample_rate
<= 16000) {
94 s
->frame_len_bits
= 9;
95 } else if (s
->sample_rate
<= 22050 ||
96 (s
->sample_rate
<= 32000 && s
->version
== 1)) {
97 s
->frame_len_bits
= 10;
99 s
->frame_len_bits
= 11;
101 s
->frame_len
= 1 << s
->frame_len_bits
;
102 if (s
->use_variable_block_len
) {
104 nb
= ((flags2
>> 3) & 3) + 1;
105 if ((s
->bit_rate
/ s
->nb_channels
) >= 32000)
107 nb_max
= s
->frame_len_bits
- BLOCK_MIN_BITS
;
110 s
->nb_block_sizes
= nb
+ 1;
112 s
->nb_block_sizes
= 1;
115 /* init rate dependent parameters */
116 s
->use_noise_coding
= 1;
117 high_freq
= s
->sample_rate
* 0.5;
119 /* if version 2, then the rates are normalized */
120 sample_rate1
= s
->sample_rate
;
121 if (s
->version
== 2) {
122 if (sample_rate1
>= 44100)
123 sample_rate1
= 44100;
124 else if (sample_rate1
>= 22050)
125 sample_rate1
= 22050;
126 else if (sample_rate1
>= 16000)
127 sample_rate1
= 16000;
128 else if (sample_rate1
>= 11025)
129 sample_rate1
= 11025;
130 else if (sample_rate1
>= 8000)
134 bps
= (float)s
->bit_rate
/ (float)(s
->nb_channels
* s
->sample_rate
);
135 s
->byte_offset_bits
= av_log2((int)(bps
* s
->frame_len
/ 8.0 + 0.5)) + 2;
137 /* compute high frequency value and choose if noise coding should
140 if (s
->nb_channels
== 2)
142 if (sample_rate1
== 44100) {
144 s
->use_noise_coding
= 0;
146 high_freq
= high_freq
* 0.4;
147 } else if (sample_rate1
== 22050) {
149 s
->use_noise_coding
= 0;
150 else if (bps1
>= 0.72)
151 high_freq
= high_freq
* 0.7;
153 high_freq
= high_freq
* 0.6;
154 } else if (sample_rate1
== 16000) {
156 high_freq
= high_freq
* 0.5;
158 high_freq
= high_freq
* 0.3;
159 } else if (sample_rate1
== 11025) {
160 high_freq
= high_freq
* 0.7;
161 } else if (sample_rate1
== 8000) {
163 high_freq
= high_freq
* 0.5;
164 } else if (bps
> 0.75) {
165 s
->use_noise_coding
= 0;
167 high_freq
= high_freq
* 0.65;
171 high_freq
= high_freq
* 0.75;
172 } else if (bps
>= 0.6) {
173 high_freq
= high_freq
* 0.6;
175 high_freq
= high_freq
* 0.5;
178 dprintf(s
->avctx
, "flags2=0x%x\n", flags2
);
179 dprintf(s
->avctx
, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
180 s
->version
, s
->nb_channels
, s
->sample_rate
, s
->bit_rate
,
182 dprintf(s
->avctx
, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
183 bps
, bps1
, high_freq
, s
->byte_offset_bits
);
184 dprintf(s
->avctx
, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
185 s
->use_noise_coding
, s
->use_exp_vlc
, s
->nb_block_sizes
);
187 /* compute the scale factor band sizes for each MDCT block size */
189 int a
, b
, pos
, lpos
, k
, block_len
, i
, j
, n
;
190 const uint8_t *table
;
192 if (s
->version
== 1) {
197 for(k
= 0; k
< s
->nb_block_sizes
; k
++) {
198 block_len
= s
->frame_len
>> k
;
200 if (s
->version
== 1) {
203 a
= wma_critical_freqs
[i
];
205 pos
= ((block_len
* 2 * a
) + (b
>> 1)) / b
;
208 s
->exponent_bands
[0][i
] = pos
- lpos
;
209 if (pos
>= block_len
) {
215 s
->exponent_sizes
[0] = i
;
217 /* hardcoded tables */
219 a
= s
->frame_len_bits
- BLOCK_MIN_BITS
- k
;
221 if (s
->sample_rate
>= 44100)
222 table
= exponent_band_44100
[a
];
223 else if (s
->sample_rate
>= 32000)
224 table
= exponent_band_32000
[a
];
225 else if (s
->sample_rate
>= 22050)
226 table
= exponent_band_22050
[a
];
231 s
->exponent_bands
[k
][i
] = table
[i
];
232 s
->exponent_sizes
[k
] = n
;
237 a
= wma_critical_freqs
[i
];
239 pos
= ((block_len
* 2 * a
) + (b
<< 1)) / (4 * b
);
244 s
->exponent_bands
[k
][j
++] = pos
- lpos
;
245 if (pos
>= block_len
)
249 s
->exponent_sizes
[k
] = j
;
253 /* max number of coefs */
254 s
->coefs_end
[k
] = (s
->frame_len
- ((s
->frame_len
* 9) / 100)) >> k
;
255 /* high freq computation */
256 s
->high_band_start
[k
] = (int)((block_len
* 2 * high_freq
) /
257 s
->sample_rate
+ 0.5);
258 n
= s
->exponent_sizes
[k
];
264 pos
+= s
->exponent_bands
[k
][i
];
266 if (start
< s
->high_band_start
[k
])
267 start
= s
->high_band_start
[k
];
268 if (end
> s
->coefs_end
[k
])
269 end
= s
->coefs_end
[k
];
271 s
->exponent_high_bands
[k
][j
++] = end
- start
;
273 s
->exponent_high_sizes
[k
] = j
;
275 tprintf(s
->avctx
, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
278 s
->high_band_start
[k
],
279 s
->exponent_high_sizes
[k
]);
280 for(j
=0;j
<s
->exponent_high_sizes
[k
];j
++)
281 tprintf(s
->avctx
, " %d", s
->exponent_high_bands
[k
][j
]);
282 tprintf(s
->avctx
, "\n");
290 for(i
= 0; i
< s
->nb_block_sizes
; i
++) {
291 tprintf(s
->avctx
, "%5d: n=%2d:",
293 s
->exponent_sizes
[i
]);
294 for(j
=0;j
<s
->exponent_sizes
[i
];j
++)
295 tprintf(s
->avctx
, " %d", s
->exponent_bands
[i
][j
]);
296 tprintf(s
->avctx
, "\n");
301 /* init MDCT windows : simple sinus window */
302 for(i
= 0; i
< s
->nb_block_sizes
; i
++) {
304 n
= 1 << (s
->frame_len_bits
- i
);
305 ff_sine_window_init(ff_sine_windows
[s
->frame_len_bits
- i
- 7], n
);
306 s
->windows
[i
] = ff_sine_windows
[s
->frame_len_bits
- i
- 7];
309 s
->reset_block_lengths
= 1;
311 if (s
->use_noise_coding
) {
313 /* init the noise generator */
315 s
->noise_mult
= 0.02;
317 s
->noise_mult
= 0.04;
320 for(i
=0;i
<NOISE_TAB_SIZE
;i
++)
321 s
->noise_table
[i
] = 1.0 * s
->noise_mult
;
327 norm
= (1.0 / (float)(1LL << 31)) * sqrt(3) * s
->noise_mult
;
328 for(i
=0;i
<NOISE_TAB_SIZE
;i
++) {
329 seed
= seed
* 314159 + 1;
330 s
->noise_table
[i
] = (float)((int)seed
) * norm
;
336 /* choose the VLC tables for the coefficients */
338 if (s
->sample_rate
>= 32000) {
341 else if (bps1
< 1.16)
344 s
->coef_vlcs
[0]= &coef_vlcs
[coef_vlc_table
* 2 ];
345 s
->coef_vlcs
[1]= &coef_vlcs
[coef_vlc_table
* 2 + 1];
346 init_coef_vlc(&s
->coef_vlc
[0], &s
->run_table
[0], &s
->level_table
[0], &s
->int_table
[0],
348 init_coef_vlc(&s
->coef_vlc
[1], &s
->run_table
[1], &s
->level_table
[1], &s
->int_table
[1],
354 int ff_wma_total_gain_to_bits(int total_gain
){
355 if (total_gain
< 15) return 13;
356 else if (total_gain
< 32) return 12;
357 else if (total_gain
< 40) return 11;
358 else if (total_gain
< 45) return 10;
362 int ff_wma_end(AVCodecContext
*avctx
)
364 WMACodecContext
*s
= avctx
->priv_data
;
367 for(i
= 0; i
< s
->nb_block_sizes
; i
++)
368 ff_mdct_end(&s
->mdct_ctx
[i
]);
370 if (s
->use_exp_vlc
) {
371 free_vlc(&s
->exp_vlc
);
373 if (s
->use_noise_coding
) {
374 free_vlc(&s
->hgain_vlc
);
376 for(i
= 0;i
< 2; i
++) {
377 free_vlc(&s
->coef_vlc
[i
]);
378 av_free(s
->run_table
[i
]);
379 av_free(s
->level_table
[i
]);
380 av_free(s
->int_table
[i
]);