2 * WMA compatible decoder
4 * Extracted 2009 from the mplayer source code 2009-02-10.
6 * Copyright (c) 2002 The FFmpeg Project
8 * Licensed under the GNU Lesser General Public License.
9 * For licencing details see COPYING.LIB.
12 /** * \file wmadec_filter.c paraslash's WMA decoder. */
15 * This decoder handles Microsoft Windows Media Audio data version 2.
18 #define _XOPEN_SOURCE 600
36 #include "bitstream.h"
43 #define BLOCK_MIN_BITS 7
44 #define BLOCK_MAX_BITS 11
45 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
47 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
49 /* XXX: find exact max size */
50 #define HIGH_BAND_MAX_SIZE 16
52 /* XXX: is it a suitable value ? */
53 #define MAX_CODED_SUPERFRAME_SIZE 16384
55 #define MAX_CHANNELS 2
57 #define NOISE_TAB_SIZE 8192
59 #define LSP_POW_BITS 7
61 struct private_wmadec_data
{
62 struct asf_header_info ahi
;
63 struct getbit_context gb
;
64 int use_bit_reservoir
;
65 int use_variable_block_len
;
66 int use_exp_vlc
; ///< exponent coding: 0 = lsp, 1 = vlc + delta
67 int use_noise_coding
; ///< true if perceptual noise is added
70 int exponent_sizes
[BLOCK_NB_SIZES
];
71 uint16_t exponent_bands
[BLOCK_NB_SIZES
][25];
72 int high_band_start
[BLOCK_NB_SIZES
]; ///< index of first coef in high band
73 int coefs_start
; ///< first coded coef
74 int coefs_end
[BLOCK_NB_SIZES
]; ///< max number of coded coefficients
75 int exponent_high_sizes
[BLOCK_NB_SIZES
];
76 int exponent_high_bands
[BLOCK_NB_SIZES
][HIGH_BAND_MAX_SIZE
];
79 /* coded values in high bands */
80 int high_band_coded
[MAX_CHANNELS
][HIGH_BAND_MAX_SIZE
];
81 int high_band_values
[MAX_CHANNELS
][HIGH_BAND_MAX_SIZE
];
83 /* there are two possible tables for spectral coefficients */
84 struct vlc coef_vlc
[2];
85 uint16_t *run_table
[2];
86 uint16_t *level_table
[2];
87 uint16_t *int_table
[2];
88 const struct coef_vlc_table
*coef_vlcs
[2];
90 int frame_len
; ///< frame length in samples
91 int frame_len_bits
; ///< frame_len = 1 << frame_len_bits
92 int nb_block_sizes
; ///< number of block sizes
94 int reset_block_lengths
;
95 int block_len_bits
; ///< log2 of current block length
96 int next_block_len_bits
; ///< log2 of next block length
97 int prev_block_len_bits
; ///< log2 of prev block length
98 int block_len
; ///< block length in samples
99 int block_num
; ///< block number in current frame
100 int block_pos
; ///< current position in frame
101 uint8_t ms_stereo
; ///< true if mid/side stereo mode
102 uint8_t channel_coded
[MAX_CHANNELS
]; ///< true if channel is coded
103 int exponents_bsize
[MAX_CHANNELS
]; ///< log2 ratio frame/exp. length
104 float exponents
[MAX_CHANNELS
][BLOCK_MAX_SIZE
];
105 float max_exponent
[MAX_CHANNELS
];
106 int16_t coefs1
[MAX_CHANNELS
][BLOCK_MAX_SIZE
];
107 float coefs
[MAX_CHANNELS
][BLOCK_MAX_SIZE
];
108 float output
[BLOCK_MAX_SIZE
* 2];
109 struct mdct_context
*mdct_ctx
[BLOCK_NB_SIZES
];
110 float *windows
[BLOCK_NB_SIZES
];
111 /* output buffer for one frame and the last for IMDCT windowing */
112 float frame_out
[MAX_CHANNELS
][BLOCK_MAX_SIZE
* 2];
113 /* last frame info */
114 uint8_t last_superframe
[MAX_CODED_SUPERFRAME_SIZE
+ 4]; /* padding added */
116 int last_superframe_len
;
117 float noise_table
[NOISE_TAB_SIZE
];
119 float noise_mult
; /* XXX: suppress that and integrate it in the noise array */
120 /* lsp_to_curve tables */
121 float lsp_cos_table
[BLOCK_MAX_SIZE
];
122 float lsp_pow_e_table
[256];
123 float lsp_pow_m_table1
[(1 << LSP_POW_BITS
)];
124 float lsp_pow_m_table2
[(1 << LSP_POW_BITS
)];
128 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
130 #define HGAINVLCBITS 9
131 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
134 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
136 static int wmadec_cleanup(struct private_wmadec_data
*s
)
140 for (i
= 0; i
< s
->nb_block_sizes
; i
++)
141 imdct_end(s
->mdct_ctx
[i
]);
144 free_vlc(&s
->exp_vlc
);
145 if (s
->use_noise_coding
)
146 free_vlc(&s
->hgain_vlc
);
147 for (i
= 0; i
< 2; i
++) {
148 free_vlc(&s
->coef_vlc
[i
]);
149 free(s
->run_table
[i
]);
150 free(s
->level_table
[i
]);
151 free(s
->int_table
[i
]);
156 /* XXX: use same run/length optimization as mpeg decoders */
157 //FIXME maybe split decode / encode or pass flag
158 static void init_coef_vlc(struct vlc
*vlc
, uint16_t **prun_table
,
159 uint16_t **plevel_table
, uint16_t **pint_table
,
160 const struct coef_vlc_table
*vlc_table
)
162 int n
= vlc_table
->n
;
163 const uint8_t *table_bits
= vlc_table
->huffbits
;
164 const uint32_t *table_codes
= vlc_table
->huffcodes
;
165 const uint16_t *levels_table
= vlc_table
->levels
;
166 uint16_t *run_table
, *level_table
, *int_table
;
167 int i
, l
, j
, k
, level
;
169 init_vlc(vlc
, VLCBITS
, n
, table_bits
, 1, 1, table_codes
, 4, 4);
171 run_table
= para_malloc(n
* sizeof (uint16_t));
172 level_table
= para_malloc(n
* sizeof (uint16_t));
173 int_table
= para_malloc(n
* sizeof (uint16_t));
179 l
= levels_table
[k
++];
180 for (j
= 0; j
< l
; j
++) {
182 level_table
[i
] = level
;
187 *prun_table
= run_table
;
188 *plevel_table
= level_table
;
189 *pint_table
= int_table
;
192 /* compute the scale factor band sizes for each MDCT block size */
193 static void compute_scale_factor_band_sizes(struct private_wmadec_data
*s
,
196 struct asf_header_info
*ahi
= &s
->ahi
;
197 int a
, b
, pos
, lpos
, k
, block_len
, i
, j
, n
;
198 const uint8_t *table
;
201 for (k
= 0; k
< s
->nb_block_sizes
; k
++) {
202 block_len
= s
->frame_len
>> k
;
205 a
= s
->frame_len_bits
- BLOCK_MIN_BITS
- k
;
207 if (ahi
->sample_rate
>= 44100)
208 table
= exponent_band_44100
[a
];
209 else if (ahi
->sample_rate
>= 32000)
210 table
= exponent_band_32000
[a
];
211 else if (ahi
->sample_rate
>= 22050)
212 table
= exponent_band_22050
[a
];
216 for (i
= 0; i
< n
; i
++)
217 s
->exponent_bands
[k
][i
] = table
[i
];
218 s
->exponent_sizes
[k
] = n
;
222 for (i
= 0; i
< 25; i
++) {
223 a
= wma_critical_freqs
[i
];
224 b
= ahi
->sample_rate
;
225 pos
= ((block_len
* 2 * a
) + (b
<< 1)) / (4 * b
);
230 s
->exponent_bands
[k
][j
++] = pos
- lpos
;
231 if (pos
>= block_len
)
235 s
->exponent_sizes
[k
] = j
;
238 /* max number of coefs */
239 s
->coefs_end
[k
] = (s
->frame_len
- ((s
->frame_len
* 9) / 100)) >> k
;
240 /* high freq computation */
241 s
->high_band_start
[k
] = (int) ((block_len
* 2 * high_freq
)
242 / ahi
->sample_rate
+ 0.5);
243 n
= s
->exponent_sizes
[k
];
246 for (i
= 0; i
< n
; i
++) {
249 pos
+= s
->exponent_bands
[k
][i
];
251 if (start
< s
->high_band_start
[k
])
252 start
= s
->high_band_start
[k
];
253 if (end
> s
->coefs_end
[k
])
254 end
= s
->coefs_end
[k
];
256 s
->exponent_high_bands
[k
][j
++] = end
- start
;
258 s
->exponent_high_sizes
[k
] = j
;
262 static int wma_init(struct private_wmadec_data
*s
, int flags2
, struct asf_header_info
*ahi
)
265 float bps1
, high_freq
;
270 if (ahi
->sample_rate
<= 0 || ahi
->sample_rate
> 50000
271 || ahi
->channels
<= 0 || ahi
->channels
> 8
272 || ahi
->bit_rate
<= 0)
273 return -E_WMA_BAD_PARAMS
;
275 /* compute MDCT block size */
276 if (ahi
->sample_rate
<= 16000) {
277 s
->frame_len_bits
= 9;
278 } else if (ahi
->sample_rate
<= 22050) {
279 s
->frame_len_bits
= 10;
281 s
->frame_len_bits
= 11;
283 s
->frame_len
= 1 << s
->frame_len_bits
;
284 if (s
->use_variable_block_len
) {
286 nb
= ((flags2
>> 3) & 3) + 1;
287 if ((ahi
->bit_rate
/ ahi
->channels
) >= 32000)
289 nb_max
= s
->frame_len_bits
- BLOCK_MIN_BITS
;
292 s
->nb_block_sizes
= nb
+ 1;
294 s
->nb_block_sizes
= 1;
297 /* init rate dependent parameters */
298 s
->use_noise_coding
= 1;
299 high_freq
= ahi
->sample_rate
* 0.5;
301 /* wma2 rates are normalized */
302 sample_rate1
= ahi
->sample_rate
;
303 if (sample_rate1
>= 44100)
304 sample_rate1
= 44100;
305 else if (sample_rate1
>= 22050)
306 sample_rate1
= 22050;
307 else if (sample_rate1
>= 16000)
308 sample_rate1
= 16000;
309 else if (sample_rate1
>= 11025)
310 sample_rate1
= 11025;
311 else if (sample_rate1
>= 8000)
314 bps
= (float) ahi
->bit_rate
/ (float) (ahi
->channels
* ahi
->sample_rate
);
315 s
->byte_offset_bits
= wma_log2((int) (bps
* s
->frame_len
/ 8.0 + 0.5)) + 2;
317 * Compute high frequency value and choose if noise coding should be
321 if (ahi
->channels
== 2)
323 if (sample_rate1
== 44100) {
325 s
->use_noise_coding
= 0;
327 high_freq
= high_freq
* 0.4;
328 } else if (sample_rate1
== 22050) {
330 s
->use_noise_coding
= 0;
331 else if (bps1
>= 0.72)
332 high_freq
= high_freq
* 0.7;
334 high_freq
= high_freq
* 0.6;
335 } else if (sample_rate1
== 16000) {
337 high_freq
= high_freq
* 0.5;
339 high_freq
= high_freq
* 0.3;
340 } else if (sample_rate1
== 11025) {
341 high_freq
= high_freq
* 0.7;
342 } else if (sample_rate1
== 8000) {
344 high_freq
= high_freq
* 0.5;
345 } else if (bps
> 0.75) {
346 s
->use_noise_coding
= 0;
348 high_freq
= high_freq
* 0.65;
352 high_freq
= high_freq
* 0.75;
353 } else if (bps
>= 0.6) {
354 high_freq
= high_freq
* 0.6;
356 high_freq
= high_freq
* 0.5;
359 PARA_INFO_LOG("channels=%d sample_rate=%d "
360 "bitrate=%d block_align=%d\n",
361 ahi
->channels
, ahi
->sample_rate
,
362 ahi
->bit_rate
, ahi
->block_align
);
363 PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
364 "high_freq=%f bitoffset=%d\n",
365 s
->frame_len
, bps
, bps1
,
366 high_freq
, s
->byte_offset_bits
);
367 PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
368 s
->use_noise_coding
, s
->use_exp_vlc
, s
->nb_block_sizes
);
370 compute_scale_factor_band_sizes(s
, high_freq
);
371 /* init MDCT windows : simple sinus window */
372 for (i
= 0; i
< s
->nb_block_sizes
; i
++) {
374 n
= 1 << (s
->frame_len_bits
- i
);
375 sine_window_init(ff_sine_windows
[s
->frame_len_bits
- i
- 7], n
);
376 s
->windows
[i
] = ff_sine_windows
[s
->frame_len_bits
- i
- 7];
379 s
->reset_block_lengths
= 1;
381 if (s
->use_noise_coding
) {
382 /* init the noise generator */
384 s
->noise_mult
= 0.02;
386 s
->noise_mult
= 0.04;
392 norm
= (1.0 / (float) (1LL << 31)) * sqrt(3) * s
->noise_mult
;
393 for (i
= 0; i
< NOISE_TAB_SIZE
; i
++) {
394 seed
= seed
* 314159 + 1;
395 s
->noise_table
[i
] = (float) ((int) seed
) * norm
;
400 /* choose the VLC tables for the coefficients */
402 if (ahi
->sample_rate
>= 32000) {
405 else if (bps1
< 1.16)
408 s
->coef_vlcs
[0] = &coef_vlcs
[coef_vlc_table
* 2];
409 s
->coef_vlcs
[1] = &coef_vlcs
[coef_vlc_table
* 2 + 1];
410 init_coef_vlc(&s
->coef_vlc
[0], &s
->run_table
[0], &s
->level_table
[0],
411 &s
->int_table
[0], s
->coef_vlcs
[0]);
412 init_coef_vlc(&s
->coef_vlc
[1], &s
->run_table
[1], &s
->level_table
[1],
413 &s
->int_table
[1], s
->coef_vlcs
[1]);
417 static void wma_lsp_to_curve_init(struct private_wmadec_data
*s
, int frame_len
)
422 wdel
= M_PI
/ frame_len
;
423 for (i
= 0; i
< frame_len
; i
++)
424 s
->lsp_cos_table
[i
] = 2.0f
* cos(wdel
* i
);
426 /* tables for x^-0.25 computation */
427 for (i
= 0; i
< 256; i
++) {
429 s
->lsp_pow_e_table
[i
] = pow(2.0, e
* -0.25);
432 /* These two tables are needed to avoid two operations in pow_m1_4. */
434 for (i
= (1 << LSP_POW_BITS
) - 1; i
>= 0; i
--) {
435 m
= (1 << LSP_POW_BITS
) + i
;
436 a
= (float) m
*(0.5 / (1 << LSP_POW_BITS
));
438 s
->lsp_pow_m_table1
[i
] = 2 * a
- b
;
439 s
->lsp_pow_m_table2
[i
] = b
- a
;
444 static int wma_decode_init(char *initial_buf
, int len
, struct private_wmadec_data
**result
)
446 struct private_wmadec_data
*s
;
449 PARA_NOTICE_LOG("initial buf: %d bytes\n", len
);
450 s
= para_calloc(sizeof(*s
));
451 ret
= read_asf_header(initial_buf
, len
, &s
->ahi
);
457 s
->use_exp_vlc
= s
->ahi
.flags2
& 0x0001;
458 s
->use_bit_reservoir
= s
->ahi
.flags2
& 0x0002;
459 s
->use_variable_block_len
= s
->ahi
.flags2
& 0x0004;
461 ret
= wma_init(s
, s
->ahi
.flags2
, &s
->ahi
);
465 for (i
= 0; i
< s
->nb_block_sizes
; i
++) {
466 ret
= imdct_init(s
->frame_len_bits
- i
+ 1, 1, &s
->mdct_ctx
[i
]);
470 if (s
->use_noise_coding
) {
471 PARA_INFO_LOG("using noise coding\n");
472 init_vlc(&s
->hgain_vlc
, HGAINVLCBITS
,
473 sizeof (ff_wma_hgain_huffbits
), ff_wma_hgain_huffbits
,
474 1, 1, ff_wma_hgain_huffcodes
, 2, 2);
477 if (s
->use_exp_vlc
) {
478 PARA_INFO_LOG("using exp_vlc\n");
479 init_vlc(&s
->exp_vlc
, EXPVLCBITS
,
480 sizeof (ff_wma_scale_huffbits
), ff_wma_scale_huffbits
,
481 1, 1, ff_wma_scale_huffcodes
, 4, 4);
483 PARA_INFO_LOG("using curve\n");
484 wma_lsp_to_curve_init(s
, s
->frame_len
);
487 return s
->ahi
.header_len
;
491 * compute x^-0.25 with an exponent and mantissa table. We use linear
492 * interpolation to reduce the mantissa table size at a small speed
493 * expense (linear interpolation approximately doubles the number of
494 * bits of precision).
496 static inline float pow_m1_4(struct private_wmadec_data
*s
, float x
)
507 m
= (u
.v
>> (23 - LSP_POW_BITS
)) & ((1 << LSP_POW_BITS
) - 1);
508 /* build interpolation scale: 1 <= t < 2. */
509 t
.v
= ((u
.v
<< LSP_POW_BITS
) & ((1 << 23) - 1)) | (127 << 23);
510 a
= s
->lsp_pow_m_table1
[m
];
511 b
= s
->lsp_pow_m_table2
[m
];
512 return s
->lsp_pow_e_table
[e
] * (a
+ b
* t
.f
);
515 static void wma_lsp_to_curve(struct private_wmadec_data
*s
,
516 float *out
, float *val_max_ptr
, int n
, float *lsp
)
519 float p
, q
, w
, v
, val_max
;
522 for (i
= 0; i
< n
; i
++) {
525 w
= s
->lsp_cos_table
[i
];
526 for (j
= 1; j
< NB_LSP_COEFS
; j
+= 2) {
538 *val_max_ptr
= val_max
;
541 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
542 static void decode_exp_lsp(struct private_wmadec_data
*s
, int ch
)
544 float lsp_coefs
[NB_LSP_COEFS
];
547 for (i
= 0; i
< NB_LSP_COEFS
; i
++) {
548 if (i
== 0 || i
>= 8)
549 val
= get_bits(&s
->gb
, 3);
551 val
= get_bits(&s
->gb
, 4);
552 lsp_coefs
[i
] = ff_wma_lsp_codebook
[i
][val
];
555 wma_lsp_to_curve(s
, s
->exponents
[ch
], &s
->max_exponent
[ch
],
556 s
->block_len
, lsp_coefs
);
560 * Parse a vlc code, faster then get_vlc().
562 * \param bits The number of bits which will be read at once, must be
563 * identical to nb_bits in init_vlc()
565 * \param max_depth The number of times bits bits must be read to completely
566 * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
568 static int get_vlc2(struct getbit_context
*s
, VLC_TYPE(*table
)[2],
569 int bits
, int max_depth
)
575 GET_VLC(code
, re
, s
, table
, bits
, max_depth
)
580 /* Decode exponents coded with VLC codes. */
581 static int decode_exp_vlc(struct private_wmadec_data
*s
, int ch
)
583 int last_exp
, n
, code
;
584 const uint16_t *ptr
, *band_ptr
;
585 float v
, *q
, max_scale
, *q_end
;
587 band_ptr
= s
->exponent_bands
[s
->frame_len_bits
- s
->block_len_bits
];
589 q
= s
->exponents
[ch
];
590 q_end
= q
+ s
->block_len
;
595 code
= get_vlc2(&s
->gb
, s
->exp_vlc
.table
, EXPVLCBITS
, EXPMAX
);
598 /* NOTE: this offset is the same as MPEG4 AAC ! */
599 last_exp
+= code
- 60;
600 /* XXX: use a table */
601 v
= pow(10, last_exp
* (1.0 / 16.0));
609 s
->max_exponent
[ch
] = max_scale
;
613 static void vector_fmul_add(float *dst
, const float *src0
, const float *src1
,
614 const float *src2
, int src3
, int len
, int step
)
617 for (i
= 0; i
< len
; i
++)
618 dst
[i
* step
] = src0
[i
] * src1
[i
] + src2
[i
] + src3
;
621 static void vector_fmul_reverse_c(float *dst
, const float *src0
,
622 const float *src1
, int len
)
626 for (i
= 0; i
< len
; i
++)
627 dst
[i
] = src0
[i
] * src1
[-i
];
631 * Apply MDCT window and add into output.
633 * We ensure that when the windows overlap their squared sum
634 * is always 1 (MDCT reconstruction rule).
636 static void wma_window(struct private_wmadec_data
*s
, float *out
)
638 float *in
= s
->output
;
639 int block_len
, bsize
, n
;
642 if (s
->block_len_bits
<= s
->prev_block_len_bits
) {
643 block_len
= s
->block_len
;
644 bsize
= s
->frame_len_bits
- s
->block_len_bits
;
646 vector_fmul_add(out
, in
, s
->windows
[bsize
],
647 out
, 0, block_len
, 1);
650 block_len
= 1 << s
->prev_block_len_bits
;
651 n
= (s
->block_len
- block_len
) / 2;
652 bsize
= s
->frame_len_bits
- s
->prev_block_len_bits
;
654 vector_fmul_add(out
+ n
, in
+ n
, s
->windows
[bsize
],
655 out
+ n
, 0, block_len
, 1);
657 memcpy(out
+ n
+ block_len
, in
+ n
+ block_len
,
665 if (s
->block_len_bits
<= s
->next_block_len_bits
) {
666 block_len
= s
->block_len
;
667 bsize
= s
->frame_len_bits
- s
->block_len_bits
;
669 vector_fmul_reverse_c(out
, in
, s
->windows
[bsize
], block_len
);
672 block_len
= 1 << s
->next_block_len_bits
;
673 n
= (s
->block_len
- block_len
) / 2;
674 bsize
= s
->frame_len_bits
- s
->next_block_len_bits
;
676 memcpy(out
, in
, n
* sizeof (float));
678 vector_fmul_reverse_c(out
+ n
, in
+ n
, s
->windows
[bsize
],
681 memset(out
+ n
+ block_len
, 0, n
* sizeof (float));
685 static int wma_total_gain_to_bits(int total_gain
)
689 else if (total_gain
< 32)
691 else if (total_gain
< 40)
693 else if (total_gain
< 45)
700 * @return 0 if OK. 1 if last block of frame. return -1 if
701 * unrecorrable error.
703 static int wma_decode_block(struct private_wmadec_data
*s
)
705 int n
, v
, ch
, code
, bsize
;
706 int coef_nb_bits
, total_gain
;
707 int nb_coefs
[MAX_CHANNELS
];
710 /* compute current block length */
711 if (s
->use_variable_block_len
) {
712 n
= wma_log2(s
->nb_block_sizes
- 1) + 1;
714 if (s
->reset_block_lengths
) {
715 s
->reset_block_lengths
= 0;
716 v
= get_bits(&s
->gb
, n
);
717 if (v
>= s
->nb_block_sizes
)
719 s
->prev_block_len_bits
= s
->frame_len_bits
- v
;
720 v
= get_bits(&s
->gb
, n
);
721 if (v
>= s
->nb_block_sizes
)
723 s
->block_len_bits
= s
->frame_len_bits
- v
;
725 /* update block lengths */
726 s
->prev_block_len_bits
= s
->block_len_bits
;
727 s
->block_len_bits
= s
->next_block_len_bits
;
729 v
= get_bits(&s
->gb
, n
);
730 if (v
>= s
->nb_block_sizes
)
732 s
->next_block_len_bits
= s
->frame_len_bits
- v
;
734 /* fixed block len */
735 s
->next_block_len_bits
= s
->frame_len_bits
;
736 s
->prev_block_len_bits
= s
->frame_len_bits
;
737 s
->block_len_bits
= s
->frame_len_bits
;
740 /* now check if the block length is coherent with the frame length */
741 s
->block_len
= 1 << s
->block_len_bits
;
742 if ((s
->block_pos
+ s
->block_len
) > s
->frame_len
)
743 return -E_INCOHERENT_BLOCK_LEN
;
745 if (s
->ahi
.channels
== 2) {
746 s
->ms_stereo
= get_bits1(&s
->gb
);
749 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
750 int a
= get_bits1(&s
->gb
);
751 s
->channel_coded
[ch
] = a
;
755 bsize
= s
->frame_len_bits
- s
->block_len_bits
;
757 /* if no channel coded, no need to go further */
758 /* XXX: fix potential framing problems */
762 /* read total gain and extract corresponding number of bits for
763 coef escape coding */
766 int a
= get_bits(&s
->gb
, 7);
772 coef_nb_bits
= wma_total_gain_to_bits(total_gain
);
774 /* compute number of coefficients */
775 n
= s
->coefs_end
[bsize
] - s
->coefs_start
;
776 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++)
780 if (s
->use_noise_coding
) {
782 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
783 if (s
->channel_coded
[ch
]) {
785 m
= s
->exponent_high_sizes
[bsize
];
786 for (i
= 0; i
< m
; i
++) {
787 a
= get_bits1(&s
->gb
);
788 s
->high_band_coded
[ch
][i
] = a
;
789 /* if noise coding, the coefficients are not transmitted */
793 exponent_high_bands
[bsize
]
798 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
799 if (s
->channel_coded
[ch
]) {
802 n
= s
->exponent_high_sizes
[bsize
];
803 val
= (int) 0x80000000;
804 for (i
= 0; i
< n
; i
++) {
805 if (s
->high_band_coded
[ch
][i
]) {
806 if (val
== (int) 0x80000000) {
822 s
->high_band_values
[ch
][i
] =
830 /* exponents can be reused in short blocks. */
831 if ((s
->block_len_bits
== s
->frame_len_bits
) || get_bits1(&s
->gb
)) {
832 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
833 if (s
->channel_coded
[ch
]) {
834 if (s
->use_exp_vlc
) {
835 if (decode_exp_vlc(s
, ch
) < 0)
838 decode_exp_lsp(s
, ch
);
840 s
->exponents_bsize
[ch
] = bsize
;
845 /* parse spectral coefficients : just RLE encoding */
846 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
847 if (s
->channel_coded
[ch
]) {
848 struct vlc
*coef_vlc
;
849 int level
, run
, sign
, tindex
;
851 const uint16_t *level_table
, *run_table
;
853 /* special VLC tables are used for ms stereo because
854 there is potentially less energy there */
855 tindex
= (ch
== 1 && s
->ms_stereo
);
856 coef_vlc
= &s
->coef_vlc
[tindex
];
857 run_table
= s
->run_table
[tindex
];
858 level_table
= s
->level_table
[tindex
];
860 ptr
= &s
->coefs1
[ch
][0];
861 eptr
= ptr
+ nb_coefs
[ch
];
862 memset(ptr
, 0, s
->block_len
* sizeof(int16_t));
865 get_vlc2(&s
->gb
, coef_vlc
->table
, VLCBITS
,
872 } else if (code
== 0) {
874 level
= get_bits(&s
->gb
, coef_nb_bits
);
875 /* NOTE: this is rather suboptimal. reading
876 block_len_bits would be better */
878 get_bits(&s
->gb
, s
->frame_len_bits
);
881 run
= run_table
[code
];
882 level
= level_table
[code
];
884 sign
= get_bits1(&s
->gb
);
889 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
893 /* NOTE: EOB can be omitted */
902 int n4
= s
->block_len
/ 2;
903 mdct_norm
= 1.0 / (float) n4
;
906 /* finally compute the MDCT coefficients */
907 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
908 if (s
->channel_coded
[ch
]) {
910 float *coefs
, *exponents
, mult
, mult1
, noise
;
911 int i
, j
, n1
, last_high_band
, esize
;
912 float exp_power
[HIGH_BAND_MAX_SIZE
];
914 coefs1
= s
->coefs1
[ch
];
915 exponents
= s
->exponents
[ch
];
916 esize
= s
->exponents_bsize
[ch
];
917 mult
= pow(10, total_gain
* 0.05) / s
->max_exponent
[ch
];
919 coefs
= s
->coefs
[ch
];
920 if (s
->use_noise_coding
) {
922 /* very low freqs : noise */
923 for (i
= 0; i
< s
->coefs_start
; i
++) {
925 s
->noise_table
[s
->noise_index
] *
926 exponents
[i
<< bsize
>> esize
] *
930 1) & (NOISE_TAB_SIZE
- 1);
933 n1
= s
->exponent_high_sizes
[bsize
];
935 /* compute power of high bands */
936 exponents
= s
->exponents
[ch
] +
937 (s
->high_band_start
[bsize
] << bsize
);
938 last_high_band
= 0; /* avoid warning */
939 for (j
= 0; j
< n1
; j
++) {
940 n
= s
->exponent_high_bands
[s
->
946 if (s
->high_band_coded
[ch
][j
]) {
949 for (i
= 0; i
< n
; i
++) {
950 val
= exponents
[i
<< bsize
954 exp_power
[j
] = e2
/ n
;
957 exponents
+= n
<< bsize
;
960 /* main freqs and high freqs */
963 (s
->coefs_start
<< bsize
);
964 for (j
= -1; j
< n1
; j
++) {
966 n
= s
->high_band_start
[bsize
] -
969 n
= s
->exponent_high_bands
[s
->
976 if (j
>= 0 && s
->high_band_coded
[ch
][j
]) {
977 /* use noise with specified power */
982 /* XXX: use a table */
990 (s
->max_exponent
[ch
] *
993 for (i
= 0; i
< n
; i
++) {
1004 exponents
[i
<< bsize
1008 exponents
+= n
<< bsize
;
1010 /* coded values + small noise */
1011 for (i
= 0; i
< n
; i
++) {
1023 exponents
[i
<< bsize
1027 exponents
+= n
<< bsize
;
1031 /* very high freqs : noise */
1032 n
= s
->block_len
- s
->coefs_end
[bsize
];
1034 mult
* exponents
[((-1 << bsize
)) >> esize
];
1035 for (i
= 0; i
< n
; i
++) {
1037 s
->noise_table
[s
->noise_index
] *
1041 1) & (NOISE_TAB_SIZE
- 1);
1044 /* XXX: optimize more */
1045 for (i
= 0; i
< s
->coefs_start
; i
++)
1048 for (i
= 0; i
< n
; i
++) {
1051 exponents
[i
<< bsize
>> esize
] *
1054 n
= s
->block_len
- s
->coefs_end
[bsize
];
1055 for (i
= 0; i
< n
; i
++)
1061 if (s
->ms_stereo
&& s
->channel_coded
[1]) {
1066 * Nominal case for ms stereo: we do it before mdct.
1068 * No need to optimize this case because it should almost never
1071 if (!s
->channel_coded
[0]) {
1072 PARA_NOTICE_LOG("rare ms-stereo\n");
1073 memset(s
->coefs
[0], 0, sizeof(float) * s
->block_len
);
1074 s
->channel_coded
[0] = 1;
1076 for (i
= 0; i
< s
->block_len
; i
++) {
1079 s
->coefs
[0][i
] = a
+ b
;
1080 s
->coefs
[1][i
] = a
- b
;
1085 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
1089 n4
= s
->block_len
/ 2;
1090 if (s
->channel_coded
[ch
])
1091 imdct(s
->mdct_ctx
[bsize
], s
->output
, s
->coefs
[ch
]);
1092 else if (!(s
->ms_stereo
&& ch
== 1))
1093 memset(s
->output
, 0, sizeof (s
->output
));
1095 /* multiply by the window and add in the frame */
1096 index
= (s
->frame_len
/ 2) + s
->block_pos
- n4
;
1097 wma_window(s
, &s
->frame_out
[ch
][index
]);
1100 /* update block number */
1102 s
->block_pos
+= s
->block_len
;
1103 if (s
->block_pos
>= s
->frame_len
)
1110 * Clip a signed integer value into the -32768,32767 range.
1112 * \param a The value to clip.
1114 * \return The clipped value.
1116 static inline int16_t av_clip_int16(int a
)
1118 if ((a
+ 32768) & ~65535)
1119 return (a
>> 31) ^ 32767;
1124 /* Decode a frame of frame_len samples. */
1125 static int wma_decode_frame(struct private_wmadec_data
*s
, int16_t * samples
)
1127 int ret
, i
, n
, ch
, incr
;
1131 /* read each block */
1135 ret
= wma_decode_block(s
);
1142 /* convert frame to integer */
1144 incr
= s
->ahi
.channels
;
1145 for (ch
= 0; ch
< s
->ahi
.channels
; ch
++) {
1147 iptr
= s
->frame_out
[ch
];
1149 for (i
= 0; i
< n
; i
++) {
1150 *ptr
= av_clip_int16(lrintf(*iptr
++));
1153 /* prepare for next block */
1154 memmove(&s
->frame_out
[ch
][0], &s
->frame_out
[ch
][s
->frame_len
],
1155 s
->frame_len
* sizeof (float));
1160 static int wma_decode_superframe(struct private_wmadec_data
*s
, void *data
,
1161 int *data_size
, const uint8_t *buf
, int buf_size
)
1163 int ret
, nb_frames
, bit_offset
, i
, pos
, len
;
1166 static int frame_count
;
1168 if (buf_size
== 0) {
1169 s
->last_superframe_len
= 0;
1172 if (buf_size
< s
->ahi
.block_align
)
1174 buf_size
= s
->ahi
.block_align
;
1176 init_get_bits(&s
->gb
, buf
, buf_size
* 8);
1177 if (s
->use_bit_reservoir
) {
1178 /* read super frame header */
1179 skip_bits(&s
->gb
, 4); /* super frame index */
1180 nb_frames
= get_bits(&s
->gb
, 4) - 1;
1181 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1182 ret
= -E_WMA_OUTPUT_SPACE
;
1183 if ((nb_frames
+ 1) * s
->ahi
.channels
* s
->frame_len
1184 * sizeof(int16_t) > *data_size
)
1187 bit_offset
= get_bits(&s
->gb
, s
->byte_offset_bits
+ 3);
1189 if (s
->last_superframe_len
> 0) {
1190 /* add bit_offset bits to last frame */
1191 ret
= -E_WMA_BAD_SUPERFRAME
;
1192 if ((s
->last_superframe_len
+ ((bit_offset
+ 7) >> 3)) >
1193 MAX_CODED_SUPERFRAME_SIZE
)
1195 q
= s
->last_superframe
+ s
->last_superframe_len
;
1198 *q
++ = get_bits(&s
->gb
, 8);
1202 *q
++ = get_bits(&s
->gb
, len
) << (8 - len
);
1205 /* XXX: bit_offset bits into last frame */
1206 init_get_bits(&s
->gb
, s
->last_superframe
,
1207 MAX_CODED_SUPERFRAME_SIZE
* 8);
1208 /* skip unused bits */
1209 if (s
->last_bitoffset
> 0)
1210 skip_bits(&s
->gb
, s
->last_bitoffset
);
1212 * This frame is stored in the last superframe and in
1215 ret
= -E_WMA_DECODE
;
1216 if (wma_decode_frame(s
, samples
) < 0)
1219 samples
+= s
->ahi
.channels
* s
->frame_len
;
1222 /* read each frame starting from bit_offset */
1223 pos
= bit_offset
+ 4 + 4 + s
->byte_offset_bits
+ 3;
1224 init_get_bits(&s
->gb
, buf
+ (pos
>> 3),
1225 (MAX_CODED_SUPERFRAME_SIZE
- (pos
>> 3)) * 8);
1228 skip_bits(&s
->gb
, len
);
1230 s
->reset_block_lengths
= 1;
1231 for (i
= 0; i
< nb_frames
; i
++) {
1232 ret
= -E_WMA_DECODE
;
1233 if (wma_decode_frame(s
, samples
) < 0)
1236 samples
+= s
->ahi
.channels
* s
->frame_len
;
1239 /* we copy the end of the frame in the last frame buffer */
1240 pos
= get_bits_count(&s
->gb
) +
1241 ((bit_offset
+ 4 + 4 + s
->byte_offset_bits
+ 3) & ~7);
1242 s
->last_bitoffset
= pos
& 7;
1244 len
= buf_size
- pos
;
1245 ret
= -E_WMA_BAD_SUPERFRAME
;
1246 if (len
> MAX_CODED_SUPERFRAME_SIZE
|| len
< 0) {
1249 s
->last_superframe_len
= len
;
1250 memcpy(s
->last_superframe
, buf
+ pos
, len
);
1252 PARA_DEBUG_LOG("not using bit reservoir\n");
1253 ret
= -E_WMA_OUTPUT_SPACE
;
1254 if (s
->ahi
.channels
* s
->frame_len
* sizeof(int16_t) > *data_size
)
1256 /* single frame decode */
1257 ret
= -E_WMA_DECODE
;
1258 if (wma_decode_frame(s
, samples
) < 0)
1261 samples
+= s
->ahi
.channels
* s
->frame_len
;
1263 PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1264 "outbytes: %d, eaten: %d\n",
1265 frame_count
, s
->frame_len
, s
->block_len
,
1266 (int8_t *) samples
- (int8_t *) data
, s
->ahi
.block_align
);
1267 *data_size
= (int8_t *)samples
- (int8_t *)data
;
1268 return s
->ahi
.block_align
;
1270 /* reset the bit reservoir on errors */
1271 s
->last_superframe_len
= 0;
1275 static ssize_t
wmadec_convert(char *inbuffer
, size_t len
,
1276 struct filter_node
*fn
)
1278 int ret
, out_size
= fn
->bufsize
- fn
->loaded
;
1279 struct private_wmadec_data
*pwd
= fn
->private_data
;
1281 if (out_size
< 128 * 1024)
1284 ret
= wma_decode_init(inbuffer
, len
, &pwd
);
1287 fn
->private_data
= pwd
;
1288 fn
->fc
->channels
= pwd
->ahi
.channels
;
1289 fn
->fc
->samplerate
= pwd
->ahi
.sample_rate
;
1290 return pwd
->ahi
.header_len
;
1293 if (len
<= WMA_FRAME_SKIP
+ pwd
->ahi
.block_align
)
1295 ret
= wma_decode_superframe(pwd
, fn
->buf
+ fn
->loaded
,
1296 &out_size
, (uint8_t *)inbuffer
+ WMA_FRAME_SKIP
,
1297 len
- WMA_FRAME_SKIP
);
1300 fn
->loaded
+= out_size
;
1301 return ret
+ WMA_FRAME_SKIP
;
1304 static void wmadec_close(struct filter_node
*fn
)
1306 struct private_wmadec_data
*pwd
= fn
->private_data
;
1309 wmadec_cleanup(pwd
);
1312 free(fn
->private_data
);
1313 fn
->private_data
= NULL
;
1316 static void wmadec_open(struct filter_node
*fn
)
1318 fn
->bufsize
= 1024 * 1024;
1319 fn
->buf
= para_malloc(fn
->bufsize
);
1320 fn
->private_data
= NULL
;
1325 * The init function of the wma decoder.
1327 * \param f Its fields are filled in by the function.
1329 void wmadec_filter_init(struct filter
*f
)
1331 f
->open
= wmadec_open
;
1332 f
->close
= wmadec_close
;
1333 f
->convert
= wmadec_convert
;