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
, uint16_t **prun_table
,
32 float **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
;
41 int i
, l
, j
, k
, level
;
43 init_vlc(vlc
, VLCBITS
, n
, table_bits
, 1, 1, table_codes
, 4, 4, 0);
45 run_table
= av_malloc(n
* sizeof(uint16_t));
46 level_table
= av_malloc(n
* sizeof(uint16_t));
47 flevel_table
= av_malloc(n
* sizeof(*flevel_table
));
48 int_table
= av_malloc(n
* sizeof(uint16_t));
54 l
= levels_table
[k
++];
55 for (j
= 0; j
< l
; j
++) {
57 level_table
[i
] = level
;
58 flevel_table
[i
]= level
;
63 *prun_table
= run_table
;
64 *plevel_table
= flevel_table
;
65 *pint_table
= int_table
;
70 *@brief Get the samples per frame for this stream.
71 *@param sample_rate output sample_rate
72 *@param version wma version
73 *@param decode_flags codec compression features
74 *@return log2 of the number of output samples per frame
76 int av_cold
ff_wma_get_frame_len_bits(int sample_rate
, int version
,
77 unsigned int decode_flags
)
82 if (sample_rate
<= 16000) {
84 } else if (sample_rate
<= 22050 ||
85 (sample_rate
<= 32000 && version
== 1)) {
87 } else if (sample_rate
<= 48000) {
89 } else if (sample_rate
<= 96000) {
96 int tmp
= decode_flags
& 0x6;
99 } else if (tmp
== 0x4) {
101 } else if (tmp
== 0x6) {
106 return frame_len_bits
;
109 int ff_wma_init(AVCodecContext
*avctx
, int flags2
)
111 WMACodecContext
*s
= avctx
->priv_data
;
113 float bps1
, high_freq
;
118 if ( avctx
->sample_rate
<= 0 || avctx
->sample_rate
> 50000
119 || avctx
->channels
<= 0 || avctx
->channels
> 8
120 || avctx
->bit_rate
<= 0)
123 s
->sample_rate
= avctx
->sample_rate
;
124 s
->nb_channels
= avctx
->channels
;
125 s
->bit_rate
= avctx
->bit_rate
;
126 s
->block_align
= avctx
->block_align
;
128 dsputil_init(&s
->dsp
, avctx
);
130 if (avctx
->codec
->id
== CODEC_ID_WMAV1
) {
136 /* compute MDCT block size */
137 s
->frame_len_bits
= ff_wma_get_frame_len_bits(s
->sample_rate
, s
->version
, 0);
139 s
->frame_len
= 1 << s
->frame_len_bits
;
140 if (s
->use_variable_block_len
) {
142 nb
= ((flags2
>> 3) & 3) + 1;
143 if ((s
->bit_rate
/ s
->nb_channels
) >= 32000)
145 nb_max
= s
->frame_len_bits
- BLOCK_MIN_BITS
;
148 s
->nb_block_sizes
= nb
+ 1;
150 s
->nb_block_sizes
= 1;
153 /* init rate dependent parameters */
154 s
->use_noise_coding
= 1;
155 high_freq
= s
->sample_rate
* 0.5;
157 /* if version 2, then the rates are normalized */
158 sample_rate1
= s
->sample_rate
;
159 if (s
->version
== 2) {
160 if (sample_rate1
>= 44100) {
161 sample_rate1
= 44100;
162 } else if (sample_rate1
>= 22050) {
163 sample_rate1
= 22050;
164 } else if (sample_rate1
>= 16000) {
165 sample_rate1
= 16000;
166 } else if (sample_rate1
>= 11025) {
167 sample_rate1
= 11025;
168 } else if (sample_rate1
>= 8000) {
173 bps
= (float)s
->bit_rate
/ (float)(s
->nb_channels
* s
->sample_rate
);
174 s
->byte_offset_bits
= av_log2((int)(bps
* s
->frame_len
/ 8.0 + 0.5)) + 2;
176 /* compute high frequency value and choose if noise coding should
179 if (s
->nb_channels
== 2)
181 if (sample_rate1
== 44100) {
183 s
->use_noise_coding
= 0;
185 high_freq
= high_freq
* 0.4;
187 } else if (sample_rate1
== 22050) {
189 s
->use_noise_coding
= 0;
190 } else if (bps1
>= 0.72) {
191 high_freq
= high_freq
* 0.7;
193 high_freq
= high_freq
* 0.6;
195 } else if (sample_rate1
== 16000) {
197 high_freq
= high_freq
* 0.5;
199 high_freq
= high_freq
* 0.3;
201 } else if (sample_rate1
== 11025) {
202 high_freq
= high_freq
* 0.7;
203 } else if (sample_rate1
== 8000) {
205 high_freq
= high_freq
* 0.5;
206 } else if (bps
> 0.75) {
207 s
->use_noise_coding
= 0;
209 high_freq
= high_freq
* 0.65;
213 high_freq
= high_freq
* 0.75;
214 } else if (bps
>= 0.6) {
215 high_freq
= high_freq
* 0.6;
217 high_freq
= high_freq
* 0.5;
220 dprintf(s
->avctx
, "flags2=0x%x\n", flags2
);
221 dprintf(s
->avctx
, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
222 s
->version
, s
->nb_channels
, s
->sample_rate
, s
->bit_rate
,
224 dprintf(s
->avctx
, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
225 bps
, bps1
, high_freq
, s
->byte_offset_bits
);
226 dprintf(s
->avctx
, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
227 s
->use_noise_coding
, s
->use_exp_vlc
, s
->nb_block_sizes
);
229 /* compute the scale factor band sizes for each MDCT block size */
231 int a
, b
, pos
, lpos
, k
, block_len
, i
, j
, n
;
232 const uint8_t *table
;
234 if (s
->version
== 1) {
239 for (k
= 0; k
< s
->nb_block_sizes
; k
++) {
240 block_len
= s
->frame_len
>> k
;
242 if (s
->version
== 1) {
244 for (i
= 0; i
< 25; i
++) {
245 a
= wma_critical_freqs
[i
];
247 pos
= ((block_len
* 2 * a
) + (b
>> 1)) / b
;
250 s
->exponent_bands
[0][i
] = pos
- lpos
;
251 if (pos
>= block_len
) {
257 s
->exponent_sizes
[0] = i
;
259 /* hardcoded tables */
261 a
= s
->frame_len_bits
- BLOCK_MIN_BITS
- k
;
263 if (s
->sample_rate
>= 44100) {
264 table
= exponent_band_44100
[a
];
265 } else if (s
->sample_rate
>= 32000) {
266 table
= exponent_band_32000
[a
];
267 } else if (s
->sample_rate
>= 22050) {
268 table
= exponent_band_22050
[a
];
273 for (i
= 0; i
< n
; i
++)
274 s
->exponent_bands
[k
][i
] = table
[i
];
275 s
->exponent_sizes
[k
] = n
;
279 for (i
= 0; i
< 25; i
++) {
280 a
= wma_critical_freqs
[i
];
282 pos
= ((block_len
* 2 * a
) + (b
<< 1)) / (4 * b
);
287 s
->exponent_bands
[k
][j
++] = pos
- lpos
;
288 if (pos
>= block_len
)
292 s
->exponent_sizes
[k
] = j
;
296 /* max number of coefs */
297 s
->coefs_end
[k
] = (s
->frame_len
- ((s
->frame_len
* 9) / 100)) >> k
;
298 /* high freq computation */
299 s
->high_band_start
[k
] = (int)((block_len
* 2 * high_freq
) /
300 s
->sample_rate
+ 0.5);
301 n
= s
->exponent_sizes
[k
];
304 for (i
= 0; i
< n
; i
++) {
307 pos
+= s
->exponent_bands
[k
][i
];
309 if (start
< s
->high_band_start
[k
])
310 start
= s
->high_band_start
[k
];
311 if (end
> s
->coefs_end
[k
])
312 end
= s
->coefs_end
[k
];
314 s
->exponent_high_bands
[k
][j
++] = end
- start
;
316 s
->exponent_high_sizes
[k
] = j
;
318 tprintf(s
->avctx
, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
321 s
->high_band_start
[k
],
322 s
->exponent_high_sizes
[k
]);
323 for (j
= 0; j
< s
->exponent_high_sizes
[k
]; j
++)
324 tprintf(s
->avctx
, " %d", s
->exponent_high_bands
[k
][j
]);
325 tprintf(s
->avctx
, "\n");
333 for (i
= 0; i
< s
->nb_block_sizes
; i
++) {
334 tprintf(s
->avctx
, "%5d: n=%2d:",
336 s
->exponent_sizes
[i
]);
337 for (j
= 0; j
< s
->exponent_sizes
[i
]; j
++)
338 tprintf(s
->avctx
, " %d", s
->exponent_bands
[i
][j
]);
339 tprintf(s
->avctx
, "\n");
344 /* init MDCT windows : simple sinus window */
345 for (i
= 0; i
< s
->nb_block_sizes
; i
++) {
347 n
= 1 << (s
->frame_len_bits
- i
);
348 ff_sine_window_init(ff_sine_windows
[s
->frame_len_bits
- i
], n
);
349 s
->windows
[i
] = ff_sine_windows
[s
->frame_len_bits
- i
];
352 s
->reset_block_lengths
= 1;
354 if (s
->use_noise_coding
) {
356 /* init the noise generator */
357 if (s
->use_exp_vlc
) {
358 s
->noise_mult
= 0.02;
360 s
->noise_mult
= 0.04;
364 for (i
= 0; i
< NOISE_TAB_SIZE
; i
++)
365 s
->noise_table
[i
] = 1.0 * s
->noise_mult
;
371 norm
= (1.0 / (float)(1LL << 31)) * sqrt(3) * s
->noise_mult
;
372 for (i
= 0; i
< NOISE_TAB_SIZE
; i
++) {
373 seed
= seed
* 314159 + 1;
374 s
->noise_table
[i
] = (float)((int)seed
) * norm
;
380 /* choose the VLC tables for the coefficients */
382 if (s
->sample_rate
>= 32000) {
385 } else if (bps1
< 1.16) {
389 s
->coef_vlcs
[0]= &coef_vlcs
[coef_vlc_table
* 2 ];
390 s
->coef_vlcs
[1]= &coef_vlcs
[coef_vlc_table
* 2 + 1];
391 init_coef_vlc(&s
->coef_vlc
[0], &s
->run_table
[0], &s
->level_table
[0], &s
->int_table
[0],
393 init_coef_vlc(&s
->coef_vlc
[1], &s
->run_table
[1], &s
->level_table
[1], &s
->int_table
[1],
399 int ff_wma_total_gain_to_bits(int total_gain
)
401 if (total_gain
< 15) return 13;
402 else if (total_gain
< 32) return 12;
403 else if (total_gain
< 40) return 11;
404 else if (total_gain
< 45) return 10;
408 int ff_wma_end(AVCodecContext
*avctx
)
410 WMACodecContext
*s
= avctx
->priv_data
;
413 for (i
= 0; i
< s
->nb_block_sizes
; i
++)
414 ff_mdct_end(&s
->mdct_ctx
[i
]);
416 if (s
->use_exp_vlc
) {
417 free_vlc(&s
->exp_vlc
);
419 if (s
->use_noise_coding
) {
420 free_vlc(&s
->hgain_vlc
);
422 for (i
= 0; i
< 2; i
++) {
423 free_vlc(&s
->coef_vlc
[i
]);
424 av_free(s
->run_table
[i
]);
425 av_free(s
->level_table
[i
]);
426 av_free(s
->int_table
[i
]);
433 * Decode an uncompressed coefficient.
434 * @param s codec context
435 * @return the decoded coefficient
437 unsigned int ff_wma_get_large_val(GetBitContext
* gb
)
439 /** consumes up to 34 bits */
451 return get_bits_long(gb
, n_bits
);
455 * Decode run level compressed coefficients.
456 * @param avctx codec context
457 * @param gb bitstream reader context
458 * @param vlc vlc table for get_vlc2
459 * @param level_table level codes
460 * @param run_table run codes
461 * @param version 0 for wma1,2 1 for wmapro
462 * @param ptr output buffer
463 * @param offset offset in the output buffer
464 * @param num_coefs number of input coefficents
465 * @param block_len input buffer length (2^n)
466 * @param frame_len_bits number of bits for escaped run codes
467 * @param coef_nb_bits number of bits for escaped level codes
468 * @return 0 on success, -1 otherwise
470 int ff_wma_run_level_decode(AVCodecContext
* avctx
, GetBitContext
* gb
,
472 const float *level_table
, const uint16_t *run_table
,
473 int version
, WMACoef
*ptr
, int offset
,
474 int num_coefs
, int block_len
, int frame_len_bits
,
477 int code
, level
, sign
;
478 const uint32_t *ilvl
= (const uint32_t*)level_table
;
479 uint32_t *iptr
= (uint32_t*)ptr
;
480 const unsigned int coef_mask
= block_len
- 1;
481 for (; offset
< num_coefs
; offset
++) {
482 code
= get_vlc2(gb
, vlc
->table
, VLCBITS
, VLCMAX
);
485 offset
+= run_table
[code
];
486 sign
= get_bits1(gb
) - 1;
487 iptr
[offset
& coef_mask
] = ilvl
[code
] ^ sign
<<31;
488 } else if (code
== 1) {
494 level
= get_bits(gb
, coef_nb_bits
);
495 /** NOTE: this is rather suboptimal. reading
496 block_len_bits would be better */
497 offset
+= get_bits(gb
, frame_len_bits
);
499 level
= ff_wma_get_large_val(gb
);
504 av_log(avctx
,AV_LOG_ERROR
,
505 "broken escape sequence\n");
508 offset
+= get_bits(gb
, frame_len_bits
) + 4;
510 offset
+= get_bits(gb
, 2) + 1;
513 sign
= get_bits1(gb
) - 1;
514 ptr
[offset
& coef_mask
] = (level
^sign
) - sign
;
517 /** NOTE: EOB can be omitted */
518 if (offset
> num_coefs
) {
519 av_log(avctx
, AV_LOG_ERROR
, "overflow in spectral RLE, ignoring\n");