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Imported Debian version 2.4.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / wmaprodec.c
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2ba45a60
DM		 1/*
2 * Wmapro compatible decoder
3 * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
4 * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file
25 * @brief wmapro decoder implementation
26 * Wmapro is an MDCT based codec comparable to wma standard or AAC.
27 * The decoding therefore consists of the following steps:
28 * - bitstream decoding
29 * - reconstruction of per-channel data
30 * - rescaling and inverse quantization
31 * - IMDCT
32 * - windowing and overlapp-add
33 *
34 * The compressed wmapro bitstream is split into individual packets.
35 * Every such packet contains one or more wma frames.
36 * The compressed frames may have a variable length and frames may
37 * cross packet boundaries.
38 * Common to all wmapro frames is the number of samples that are stored in
39 * a frame.
40 * The number of samples and a few other decode flags are stored
41 * as extradata that has to be passed to the decoder.
42 *
43 * The wmapro frames themselves are again split into a variable number of
44 * subframes. Every subframe contains the data for 2^N time domain samples
45 * where N varies between 7 and 12.
46 *
47 * Example wmapro bitstream (in samples):
48 *
49 * || packet 0 || packet 1 || packet 2 packets
50 * ---------------------------------------------------
51 * || frame 0 || frame 1 || frame 2 || frames
52 * ---------------------------------------------------
53 * || | | || | | | || || subframes of channel 0
54 * ---------------------------------------------------
55 * || | | || | | | || || subframes of channel 1
56 * ---------------------------------------------------
57 *
58 * The frame layouts for the individual channels of a wma frame does not need
59 * to be the same.
60 *
61 * However, if the offsets and lengths of several subframes of a frame are the
62 * same, the subframes of the channels can be grouped.
63 * Every group may then use special coding techniques like M/S stereo coding
64 * to improve the compression ratio. These channel transformations do not
65 * need to be applied to a whole subframe. Instead, they can also work on
66 * individual scale factor bands (see below).
67 * The coefficients that carry the audio signal in the frequency domain
68 * are transmitted as huffman-coded vectors with 4, 2 and 1 elements.
69 * In addition to that, the encoder can switch to a runlevel coding scheme
70 * by transmitting subframe_length / 128 zero coefficients.
71 *
72 * Before the audio signal can be converted to the time domain, the
73 * coefficients have to be rescaled and inverse quantized.
74 * A subframe is therefore split into several scale factor bands that get
75 * scaled individually.
76 * Scale factors are submitted for every frame but they might be shared
77 * between the subframes of a channel. Scale factors are initially DPCM-coded.
78 * Once scale factors are shared, the differences are transmitted as runlevel
79 * codes.
80 * Every subframe length and offset combination in the frame layout shares a
81 * common quantization factor that can be adjusted for every channel by a
82 * modifier.
83 * After the inverse quantization, the coefficients get processed by an IMDCT.
84 * The resulting values are then windowed with a sine window and the first half
85 * of the values are added to the second half of the output from the previous
86 * subframe in order to reconstruct the output samples.
87 */
88
89#include <inttypes.h>
90
91#include "libavutil/float_dsp.h"
92#include "libavutil/intfloat.h"
93#include "libavutil/intreadwrite.h"
94#include "avcodec.h"
95#include "internal.h"
96#include "get_bits.h"
97#include "put_bits.h"
98#include "wmaprodata.h"
99#include "sinewin.h"
100#include "wma.h"
101#include "wma_common.h"
102
103/** current decoder limitations */
104#define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels
105#define MAX_SUBFRAMES 32 ///< max number of subframes per channel
106#define MAX_BANDS 29 ///< max number of scale factor bands
107#define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
108
109#define WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
110#define WMAPRO_BLOCK_MAX_BITS 13 ///< log2 of max block size
111#define WMAPRO_BLOCK_MIN_SIZE (1 << WMAPRO_BLOCK_MIN_BITS) ///< minimum block size
112#define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size
113#define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
114
115
116#define VLCBITS 9
117#define SCALEVLCBITS 8
118#define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
119#define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
120#define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
121#define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
122#define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
123
124static VLC sf_vlc; ///< scale factor DPCM vlc
125static VLC sf_rl_vlc; ///< scale factor run length vlc
126static VLC vec4_vlc; ///< 4 coefficients per symbol
127static VLC vec2_vlc; ///< 2 coefficients per symbol
128static VLC vec1_vlc; ///< 1 coefficient per symbol
129static VLC coef_vlc[2]; ///< coefficient run length vlc codes
130static float sin64[33]; ///< sine table for decorrelation
131
132/**
133 * @brief frame specific decoder context for a single channel
134 */
135typedef struct {
136 int16_t prev_block_len; ///< length of the previous block
137 uint8_t transmit_coefs;
138 uint8_t num_subframes;
139 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
140 uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
141 uint8_t cur_subframe; ///< current subframe number
142 uint16_t decoded_samples; ///< number of already processed samples
143 uint8_t grouped; ///< channel is part of a group
144 int quant_step; ///< quantization step for the current subframe
145 int8_t reuse_sf; ///< share scale factors between subframes
146 int8_t scale_factor_step; ///< scaling step for the current subframe
147 int max_scale_factor; ///< maximum scale factor for the current subframe
148 int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
149 int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
150 int* scale_factors; ///< pointer to the scale factor values used for decoding
151 uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
152 float* coeffs; ///< pointer to the subframe decode buffer
153 uint16_t num_vec_coeffs; ///< number of vector coded coefficients
154 DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer
155} WMAProChannelCtx;
156
157/**
158 * @brief channel group for channel transformations
159 */
160typedef struct {
161 uint8_t num_channels; ///< number of channels in the group
162 int8_t transform; ///< transform on / off
163 int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
164 float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
165 float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients
166} WMAProChannelGrp;
167
168/**
169 * @brief main decoder context
170 */
171typedef struct WMAProDecodeCtx {
172 /* generic decoder variables */
173 AVCodecContext* avctx; ///< codec context for av_log
174 AVFloatDSPContext fdsp;
175 uint8_t frame_data[MAX_FRAMESIZE +
176 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
177 PutBitContext pb; ///< context for filling the frame_data buffer
178 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
179 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
180 const float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
181
182 /* frame size dependent frame information (set during initialization) */
183 uint32_t decode_flags; ///< used compression features
184 uint8_t len_prefix; ///< frame is prefixed with its length
185 uint8_t dynamic_range_compression; ///< frame contains DRC data
186 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
187 uint16_t samples_per_frame; ///< number of samples to output
188 uint16_t log2_frame_size;
189 int8_t lfe_channel; ///< lfe channel index
190 uint8_t max_num_subframes;
191 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
192 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
193 uint16_t min_samples_per_subframe;
194 int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
195 int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
196 int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
197 int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
198
199 /* packet decode state */
200 GetBitContext pgb; ///< bitstream reader context for the packet
201 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
202 uint8_t packet_offset; ///< frame offset in the packet
203 uint8_t packet_sequence_number; ///< current packet number
204 int num_saved_bits; ///< saved number of bits
205 int frame_offset; ///< frame offset in the bit reservoir
206 int subframe_offset; ///< subframe offset in the bit reservoir
207 uint8_t packet_loss; ///< set in case of bitstream error
208 uint8_t packet_done; ///< set when a packet is fully decoded
209
210 /* frame decode state */
211 uint32_t frame_num; ///< current frame number (not used for decoding)
212 GetBitContext gb; ///< bitstream reader context
213 int buf_bit_size; ///< buffer size in bits
214 uint8_t drc_gain; ///< gain for the DRC tool
215 int8_t skip_frame; ///< skip output step
216 int8_t parsed_all_subframes; ///< all subframes decoded?
217
218 /* subframe/block decode state */
219 int16_t subframe_len; ///< current subframe length
220 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
221 int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
222 int8_t num_bands; ///< number of scale factor bands
223 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
224 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
225 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
226 int8_t esc_len; ///< length of escaped coefficients
227
228 uint8_t num_chgroups; ///< number of channel groups
229 WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
230
231 WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
232} WMAProDecodeCtx;
233
234
235/**
236 *@brief helper function to print the most important members of the context
237 *@param s context
238 */
239static av_cold void dump_context(WMAProDecodeCtx *s)
240{
241#define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
242#define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %"PRIx32"\n", a, b);
243
244 PRINT("ed sample bit depth", s->bits_per_sample);
245 PRINT_HEX("ed decode flags", s->decode_flags);
246 PRINT("samples per frame", s->samples_per_frame);
247 PRINT("log2 frame size", s->log2_frame_size);
248 PRINT("max num subframes", s->max_num_subframes);
249 PRINT("len prefix", s->len_prefix);
250 PRINT("num channels", s->avctx->channels);
251}
252
253/**
254 *@brief Uninitialize the decoder and free all resources.
255 *@param avctx codec context
256 *@return 0 on success, < 0 otherwise
257 */
258static av_cold int decode_end(AVCodecContext *avctx)
259{
260 WMAProDecodeCtx *s = avctx->priv_data;
261 int i;
262
263 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
264 ff_mdct_end(&s->mdct_ctx[i]);
265
266 return 0;
267}
268
269/**
270 *@brief Initialize the decoder.
271 *@param avctx codec context
272 *@return 0 on success, -1 otherwise
273 */
274static av_cold int decode_init(AVCodecContext *avctx)
275{
276 WMAProDecodeCtx *s = avctx->priv_data;
277 uint8_t *edata_ptr = avctx->extradata;
278 unsigned int channel_mask;
279 int i, bits;
280 int log2_max_num_subframes;
281 int num_possible_block_sizes;
282
283 if (!avctx->block_align) {
284 av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
285 return AVERROR(EINVAL);
286 }
287
288 s->avctx = avctx;
289 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
290
291 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
292
293 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
294
295 if (avctx->extradata_size >= 18) {
296 s->decode_flags = AV_RL16(edata_ptr+14);
297 channel_mask = AV_RL32(edata_ptr+2);
298 s->bits_per_sample = AV_RL16(edata_ptr);
299 /** dump the extradata */
300 for (i = 0; i < avctx->extradata_size; i++)
301 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
302 av_dlog(avctx, "\n");
303
304 } else {
305 avpriv_request_sample(avctx, "Unknown extradata size");
306 return AVERROR_PATCHWELCOME;
307 }
308
309 /** generic init */
310 s->log2_frame_size = av_log2(avctx->block_align) + 4;
311 if (s->log2_frame_size > 25) {
312 avpriv_request_sample(avctx, "Large block align");
313 return AVERROR_PATCHWELCOME;
314 }
315
316 /** frame info */
317 s->skip_frame = 1; /* skip first frame */
318 s->packet_loss = 1;
319 s->len_prefix = (s->decode_flags & 0x40);
320
321 /** get frame len */
322 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
323 if (bits > WMAPRO_BLOCK_MAX_BITS) {
324 avpriv_request_sample(avctx, "14-bit block sizes");
325 return AVERROR_PATCHWELCOME;
326 }
327 s->samples_per_frame = 1 << bits;
328
329 /** subframe info */
330 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
331 s->max_num_subframes = 1 << log2_max_num_subframes;
332 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
333 s->max_subframe_len_bit = 1;
334 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
335
336 num_possible_block_sizes = log2_max_num_subframes + 1;
337 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
338 s->dynamic_range_compression = (s->decode_flags & 0x80);
339
340 if (s->max_num_subframes > MAX_SUBFRAMES) {
341 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %"PRId8"\n",
342 s->max_num_subframes);
343 return AVERROR_INVALIDDATA;
344 }
345
346 if (s->min_samples_per_subframe < WMAPRO_BLOCK_MIN_SIZE) {
347 av_log(avctx, AV_LOG_ERROR, "min_samples_per_subframe of %d too small\n",
348 s->min_samples_per_subframe);
349 return AVERROR_INVALIDDATA;
350 }
351
352 if (s->avctx->sample_rate <= 0) {
353 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
354 return AVERROR_INVALIDDATA;
355 }
356
357 if (avctx->channels < 0) {
358 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
359 avctx->channels);
360 return AVERROR_INVALIDDATA;
361 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
362 avpriv_request_sample(avctx,
363 "More than %d channels", WMAPRO_MAX_CHANNELS);
364 return AVERROR_PATCHWELCOME;
365 }
366
367 /** init previous block len */
368 for (i = 0; i < avctx->channels; i++)
369 s->channel[i].prev_block_len = s->samples_per_frame;
370
371 /** extract lfe channel position */
372 s->lfe_channel = -1;
373
374 if (channel_mask & 8) {
375 unsigned int mask;
376 for (mask = 1; mask < 16; mask <<= 1) {
377 if (channel_mask & mask)
378 ++s->lfe_channel;
379 }
380 }
381
382 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
383 scale_huffbits, 1, 1,
384 scale_huffcodes, 2, 2, 616);
385
386 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
387 scale_rl_huffbits, 1, 1,
388 scale_rl_huffcodes, 4, 4, 1406);
389
390 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
391 coef0_huffbits, 1, 1,
392 coef0_huffcodes, 4, 4, 2108);
393
394 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
395 coef1_huffbits, 1, 1,
396 coef1_huffcodes, 4, 4, 3912);
397
398 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
399 vec4_huffbits, 1, 1,
400 vec4_huffcodes, 2, 2, 604);
401
402 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
403 vec2_huffbits, 1, 1,
404 vec2_huffcodes, 2, 2, 562);
405
406 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
407 vec1_huffbits, 1, 1,
408 vec1_huffcodes, 2, 2, 562);
409
410 /** calculate number of scale factor bands and their offsets
411 for every possible block size */
412 for (i = 0; i < num_possible_block_sizes; i++) {
413 int subframe_len = s->samples_per_frame >> i;
414 int x;
415 int band = 1;
416
417 s->sfb_offsets[i][0] = 0;
418
419 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
420 int offset = (subframe_len * 2 * critical_freq[x])
421 / s->avctx->sample_rate + 2;
422 offset &= ~3;
423 if (offset > s->sfb_offsets[i][band - 1])
424 s->sfb_offsets[i][band++] = offset;
425 }
426 s->sfb_offsets[i][band - 1] = subframe_len;
427 s->num_sfb[i] = band - 1;
428 if (s->num_sfb[i] <= 0) {
429 av_log(avctx, AV_LOG_ERROR, "num_sfb invalid\n");
430 return AVERROR_INVALIDDATA;
431 }
432 }
433
434
435 /** Scale factors can be shared between blocks of different size
436 as every block has a different scale factor band layout.
437 The matrix sf_offsets is needed to find the correct scale factor.
438 */
439
440 for (i = 0; i < num_possible_block_sizes; i++) {
441 int b;
442 for (b = 0; b < s->num_sfb[i]; b++) {
443 int x;
444 int offset = ((s->sfb_offsets[i][b]
445 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
446 for (x = 0; x < num_possible_block_sizes; x++) {
447 int v = 0;
448 while (s->sfb_offsets[x][v + 1] << x < offset) {
449 v++;
450 av_assert0(v < MAX_BANDS);
451 }
452 s->sf_offsets[i][x][b] = v;
453 }
454 }
455 }
456
457 /** init MDCT, FIXME: only init needed sizes */
458 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
459 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
460 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
461 / (1 << (s->bits_per_sample - 1)));
462
463 /** init MDCT windows: simple sine window */
464 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
465 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
466 ff_init_ff_sine_windows(win_idx);
467 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
468 }
469
470 /** calculate subwoofer cutoff values */
471 for (i = 0; i < num_possible_block_sizes; i++) {
472 int block_size = s->samples_per_frame >> i;
473 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
474 / s->avctx->sample_rate;
475 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
476 }
477
478 /** calculate sine values for the decorrelation matrix */
479 for (i = 0; i < 33; i++)
480 sin64[i] = sin(i*M_PI / 64.0);
481
482 if (avctx->debug & FF_DEBUG_BITSTREAM)
483 dump_context(s);
484
485 avctx->channel_layout = channel_mask;
486
487 return 0;
488}
489
490/**
491 *@brief Decode the subframe length.
492 *@param s context
493 *@param offset sample offset in the frame
494 *@return decoded subframe length on success, < 0 in case of an error
495 */
496static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
497{
498 int frame_len_shift = 0;
499 int subframe_len;
500
501 /** no need to read from the bitstream when only one length is possible */
502 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
503 return s->min_samples_per_subframe;
504
505 if (get_bits_left(&s->gb) < 1)
506 return AVERROR_INVALIDDATA;
507
508 /** 1 bit indicates if the subframe is of maximum length */
509 if (s->max_subframe_len_bit) {
510 if (get_bits1(&s->gb))
511 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
512 } else
513 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
514
515 subframe_len = s->samples_per_frame >> frame_len_shift;
516
517 /** sanity check the length */
518 if (subframe_len < s->min_samples_per_subframe ||
519 subframe_len > s->samples_per_frame) {
520 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
521 subframe_len);
522 return AVERROR_INVALIDDATA;
523 }
524 return subframe_len;
525}
526
527/**
528 *@brief Decode how the data in the frame is split into subframes.
529 * Every WMA frame contains the encoded data for a fixed number of
530 * samples per channel. The data for every channel might be split
531 * into several subframes. This function will reconstruct the list of
532 * subframes for every channel.
533 *
534 * If the subframes are not evenly split, the algorithm estimates the
535 * channels with the lowest number of total samples.
536 * Afterwards, for each of these channels a bit is read from the
537 * bitstream that indicates if the channel contains a subframe with the
538 * next subframe size that is going to be read from the bitstream or not.
539 * If a channel contains such a subframe, the subframe size gets added to
540 * the channel's subframe list.
541 * The algorithm repeats these steps until the frame is properly divided
542 * between the individual channels.
543 *
544 *@param s context
545 *@return 0 on success, < 0 in case of an error
546 */
547static int decode_tilehdr(WMAProDecodeCtx *s)
548{
549 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
550 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
551 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
552 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
553 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
554 int c;
555
556 /* Should never consume more than 3073 bits (256 iterations for the
557 * while loop when always the minimum amount of 128 samples is subtracted
558 * from missing samples in the 8 channel case).
559 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
560 */
561
562 /** reset tiling information */
563 for (c = 0; c < s->avctx->channels; c++)
564 s->channel[c].num_subframes = 0;
565
566 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
567 fixed_channel_layout = 1;
568
569 /** loop until the frame data is split between the subframes */
570 do {
571 int subframe_len;
572
573 /** check which channels contain the subframe */
574 for (c = 0; c < s->avctx->channels; c++) {
575 if (num_samples[c] == min_channel_len) {
576 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
577 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
578 contains_subframe[c] = 1;
579 else
580 contains_subframe[c] = get_bits1(&s->gb);
581 } else
582 contains_subframe[c] = 0;
583 }
584
585 /** get subframe length, subframe_len == 0 is not allowed */
586 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
587 return AVERROR_INVALIDDATA;
588
589 /** add subframes to the individual channels and find new min_channel_len */
590 min_channel_len += subframe_len;
591 for (c = 0; c < s->avctx->channels; c++) {
592 WMAProChannelCtx* chan = &s->channel[c];
593
594 if (contains_subframe[c]) {
595 if (chan->num_subframes >= MAX_SUBFRAMES) {
596 av_log(s->avctx, AV_LOG_ERROR,
597 "broken frame: num subframes > 31\n");
598 return AVERROR_INVALIDDATA;
599 }
600 chan->subframe_len[chan->num_subframes] = subframe_len;
601 num_samples[c] += subframe_len;
602 ++chan->num_subframes;
603 if (num_samples[c] > s->samples_per_frame) {
604 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
605 "channel len > samples_per_frame\n");
606 return AVERROR_INVALIDDATA;
607 }
608 } else if (num_samples[c] <= min_channel_len) {
609 if (num_samples[c] < min_channel_len) {
610 channels_for_cur_subframe = 0;
611 min_channel_len = num_samples[c];
612 }
613 ++channels_for_cur_subframe;
614 }
615 }
616 } while (min_channel_len < s->samples_per_frame);
617
618 for (c = 0; c < s->avctx->channels; c++) {
619 int i;
620 int offset = 0;
621 for (i = 0; i < s->channel[c].num_subframes; i++) {
622 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
623 " len %i\n", s->frame_num, c, i,
624 s->channel[c].subframe_len[i]);
625 s->channel[c].subframe_offset[i] = offset;
626 offset += s->channel[c].subframe_len[i];
627 }
628 }
629
630 return 0;
631}
632
633/**
634 *@brief Calculate a decorrelation matrix from the bitstream parameters.
635 *@param s codec context
636 *@param chgroup channel group for which the matrix needs to be calculated
637 */
638static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
639 WMAProChannelGrp *chgroup)
640{
641 int i;
642 int offset = 0;
643 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
644 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
645 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
646
647 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
648 rotation_offset[i] = get_bits(&s->gb, 6);
649
650 for (i = 0; i < chgroup->num_channels; i++)
651 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
652 get_bits1(&s->gb) ? 1.0 : -1.0;
653
654 for (i = 1; i < chgroup->num_channels; i++) {
655 int x;
656 for (x = 0; x < i; x++) {
657 int y;
658 for (y = 0; y < i + 1; y++) {
659 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
660 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
661 int n = rotation_offset[offset + x];
662 float sinv;
663 float cosv;
664
665 if (n < 32) {
666 sinv = sin64[n];
667 cosv = sin64[32 - n];
668 } else {
669 sinv = sin64[64 - n];
670 cosv = -sin64[n - 32];
671 }
672
673 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
674 (v1 * sinv) - (v2 * cosv);
675 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
676 (v1 * cosv) + (v2 * sinv);
677 }
678 }
679 offset += i;
680 }
681}
682
683/**
684 *@brief Decode channel transformation parameters
685 *@param s codec context
686 *@return >= 0 in case of success, < 0 in case of bitstream errors
687 */
688static int decode_channel_transform(WMAProDecodeCtx* s)
689{
690 int i;
691 /* should never consume more than 1921 bits for the 8 channel case
692 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
693 * + MAX_CHANNELS + MAX_BANDS + 1)
694 */
695
696 /** in the one channel case channel transforms are pointless */
697 s->num_chgroups = 0;
698 if (s->avctx->channels > 1) {
699 int remaining_channels = s->channels_for_cur_subframe;
700
701 if (get_bits1(&s->gb)) {
702 avpriv_request_sample(s->avctx,
703 "Channel transform bit");
704 return AVERROR_PATCHWELCOME;
705 }
706
707 for (s->num_chgroups = 0; remaining_channels &&
708 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
709 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
710 float** channel_data = chgroup->channel_data;
711 chgroup->num_channels = 0;
712 chgroup->transform = 0;
713
714 /** decode channel mask */
715 if (remaining_channels > 2) {
716 for (i = 0; i < s->channels_for_cur_subframe; i++) {
717 int channel_idx = s->channel_indexes_for_cur_subframe[i];
718 if (!s->channel[channel_idx].grouped
719 && get_bits1(&s->gb)) {
720 ++chgroup->num_channels;
721 s->channel[channel_idx].grouped = 1;
722 *channel_data++ = s->channel[channel_idx].coeffs;
723 }
724 }
725 } else {
726 chgroup->num_channels = remaining_channels;
727 for (i = 0; i < s->channels_for_cur_subframe; i++) {
728 int channel_idx = s->channel_indexes_for_cur_subframe[i];
729 if (!s->channel[channel_idx].grouped)
730 *channel_data++ = s->channel[channel_idx].coeffs;
731 s->channel[channel_idx].grouped = 1;
732 }
733 }
734
735 /** decode transform type */
736 if (chgroup->num_channels == 2) {
737 if (get_bits1(&s->gb)) {
738 if (get_bits1(&s->gb)) {
739 avpriv_request_sample(s->avctx,
740 "Unknown channel transform type");
741 return AVERROR_PATCHWELCOME;
742 }
743 } else {
744 chgroup->transform = 1;
745 if (s->avctx->channels == 2) {
746 chgroup->decorrelation_matrix[0] = 1.0;
747 chgroup->decorrelation_matrix[1] = -1.0;
748 chgroup->decorrelation_matrix[2] = 1.0;
749 chgroup->decorrelation_matrix[3] = 1.0;
750 } else {
751 /** cos(pi/4) */
752 chgroup->decorrelation_matrix[0] = 0.70703125;
753 chgroup->decorrelation_matrix[1] = -0.70703125;
754 chgroup->decorrelation_matrix[2] = 0.70703125;
755 chgroup->decorrelation_matrix[3] = 0.70703125;
756 }
757 }
758 } else if (chgroup->num_channels > 2) {
759 if (get_bits1(&s->gb)) {
760 chgroup->transform = 1;
761 if (get_bits1(&s->gb)) {
762 decode_decorrelation_matrix(s, chgroup);
763 } else {
764 /** FIXME: more than 6 coupled channels not supported */
765 if (chgroup->num_channels > 6) {
766 avpriv_request_sample(s->avctx,
767 "Coupled channels > 6");
768 } else {
769 memcpy(chgroup->decorrelation_matrix,
770 default_decorrelation[chgroup->num_channels],
771 chgroup->num_channels * chgroup->num_channels *
772 sizeof(*chgroup->decorrelation_matrix));
773 }
774 }
775 }
776 }
777
778 /** decode transform on / off */
779 if (chgroup->transform) {
780 if (!get_bits1(&s->gb)) {
781 int i;
782 /** transform can be enabled for individual bands */
783 for (i = 0; i < s->num_bands; i++) {
784 chgroup->transform_band[i] = get_bits1(&s->gb);
785 }
786 } else {
787 memset(chgroup->transform_band, 1, s->num_bands);
788 }
789 }
790 remaining_channels -= chgroup->num_channels;
791 }
792 }
793 return 0;
794}
795
796/**
797 *@brief Extract the coefficients from the bitstream.
798 *@param s codec context
799 *@param c current channel number
800 *@return 0 on success, < 0 in case of bitstream errors
801 */
802static int decode_coeffs(WMAProDecodeCtx *s, int c)
803{
804 /* Integers 0..15 as single-precision floats. The table saves a
805 costly int to float conversion, and storing the values as
806 integers allows fast sign-flipping. */
807 static const uint32_t fval_tab[16] = {
808 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
809 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
810 0x41000000, 0x41100000, 0x41200000, 0x41300000,
811 0x41400000, 0x41500000, 0x41600000, 0x41700000,
812 };
813 int vlctable;
814 VLC* vlc;
815 WMAProChannelCtx* ci = &s->channel[c];
816 int rl_mode = 0;
817 int cur_coeff = 0;
818 int num_zeros = 0;
819 const uint16_t* run;
820 const float* level;
821
822 av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
823
824 vlctable = get_bits1(&s->gb);
825 vlc = &coef_vlc[vlctable];
826
827 if (vlctable) {
828 run = coef1_run;
829 level = coef1_level;
830 } else {
831 run = coef0_run;
832 level = coef0_level;
833 }
834
835 /** decode vector coefficients (consumes up to 167 bits per iteration for
836 4 vector coded large values) */
837 while ((s->transmit_num_vec_coeffs || !rl_mode) &&
838 (cur_coeff + 3 < ci->num_vec_coeffs)) {
839 uint32_t vals[4];
840 int i;
841 unsigned int idx;
842
843 idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
844
845 if (idx == HUFF_VEC4_SIZE - 1) {
846 for (i = 0; i < 4; i += 2) {
847 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
848 if (idx == HUFF_VEC2_SIZE - 1) {
849 uint32_t v0, v1;
850 v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
851 if (v0 == HUFF_VEC1_SIZE - 1)
852 v0 += ff_wma_get_large_val(&s->gb);
853 v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
854 if (v1 == HUFF_VEC1_SIZE - 1)
855 v1 += ff_wma_get_large_val(&s->gb);
856 vals[i ] = av_float2int(v0);
857 vals[i+1] = av_float2int(v1);
858 } else {
859 vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
860 vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
861 }
862 }
863 } else {
864 vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
865 vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
866 vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
867 vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
868 }
869
870 /** decode sign */
871 for (i = 0; i < 4; i++) {
872 if (vals[i]) {
873 uint32_t sign = get_bits1(&s->gb) - 1;
874 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
875 num_zeros = 0;
876 } else {
877 ci->coeffs[cur_coeff] = 0;
878 /** switch to run level mode when subframe_len / 128 zeros
879 were found in a row */
880 rl_mode |= (++num_zeros > s->subframe_len >> 8);
881 }
882 ++cur_coeff;
883 }
884 }
885
886 /** decode run level coded coefficients */
887 if (cur_coeff < s->subframe_len) {
888 memset(&ci->coeffs[cur_coeff], 0,
889 sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
890 if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
891 level, run, 1, ci->coeffs,
892 cur_coeff, s->subframe_len,
893 s->subframe_len, s->esc_len, 0))
894 return AVERROR_INVALIDDATA;
895 }
896
897 return 0;
898}
899
900/**
901 *@brief Extract scale factors from the bitstream.
902 *@param s codec context
903 *@return 0 on success, < 0 in case of bitstream errors
904 */
905static int decode_scale_factors(WMAProDecodeCtx* s)
906{
907 int i;
908
909 /** should never consume more than 5344 bits
910 * MAX_CHANNELS * (1 + MAX_BANDS * 23)
911 */
912
913 for (i = 0; i < s->channels_for_cur_subframe; i++) {
914 int c = s->channel_indexes_for_cur_subframe[i];
915 int* sf;
916 int* sf_end;
917 s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
918 sf_end = s->channel[c].scale_factors + s->num_bands;
919
920 /** resample scale factors for the new block size
921 * as the scale factors might need to be resampled several times
922 * before some new values are transmitted, a backup of the last
923 * transmitted scale factors is kept in saved_scale_factors
924 */
925 if (s->channel[c].reuse_sf) {
926 const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
927 int b;
928 for (b = 0; b < s->num_bands; b++)
929 s->channel[c].scale_factors[b] =
930 s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
931 }
932
933 if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
934
935 if (!s->channel[c].reuse_sf) {
936 int val;
937 /** decode DPCM coded scale factors */
938 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
939 val = 45 / s->channel[c].scale_factor_step;
940 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
941 val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
942 *sf = val;
943 }
944 } else {
945 int i;
946 /** run level decode differences to the resampled factors */
947 for (i = 0; i < s->num_bands; i++) {
948 int idx;
949 int skip;
950 int val;
951 int sign;
952
953 idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
954
955 if (!idx) {
956 uint32_t code = get_bits(&s->gb, 14);
957 val = code >> 6;
958 sign = (code & 1) - 1;
959 skip = (code & 0x3f) >> 1;
960 } else if (idx == 1) {
961 break;
962 } else {
963 skip = scale_rl_run[idx];
964 val = scale_rl_level[idx];
965 sign = get_bits1(&s->gb)-1;
966 }
967
968 i += skip;
969 if (i >= s->num_bands) {
970 av_log(s->avctx, AV_LOG_ERROR,
971 "invalid scale factor coding\n");
972 return AVERROR_INVALIDDATA;
973 }
974 s->channel[c].scale_factors[i] += (val ^ sign) - sign;
975 }
976 }
977 /** swap buffers */
978 s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
979 s->channel[c].table_idx = s->table_idx;
980 s->channel[c].reuse_sf = 1;
981 }
982
983 /** calculate new scale factor maximum */
984 s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
985 for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
986 s->channel[c].max_scale_factor =
987 FFMAX(s->channel[c].max_scale_factor, *sf);
988 }
989
990 }
991 return 0;
992}
993
994/**
995 *@brief Reconstruct the individual channel data.
996 *@param s codec context
997 */
998static void inverse_channel_transform(WMAProDecodeCtx *s)
999{
1000 int i;
1001
1002 for (i = 0; i < s->num_chgroups; i++) {
1003 if (s->chgroup[i].transform) {
1004 float data[WMAPRO_MAX_CHANNELS];
1005 const int num_channels = s->chgroup[i].num_channels;
1006 float** ch_data = s->chgroup[i].channel_data;
1007 float** ch_end = ch_data + num_channels;
1008 const int8_t* tb = s->chgroup[i].transform_band;
1009 int16_t* sfb;
1010
1011 /** multichannel decorrelation */
1012 for (sfb = s->cur_sfb_offsets;
1013 sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
1014 int y;
1015 if (*tb++ == 1) {
1016 /** multiply values with the decorrelation_matrix */
1017 for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
1018 const float* mat = s->chgroup[i].decorrelation_matrix;
1019 const float* data_end = data + num_channels;
1020 float* data_ptr = data;
1021 float** ch;
1022
1023 for (ch = ch_data; ch < ch_end; ch++)
1024 *data_ptr++ = (*ch)[y];
1025
1026 for (ch = ch_data; ch < ch_end; ch++) {
1027 float sum = 0;
1028 data_ptr = data;
1029 while (data_ptr < data_end)
1030 sum += *data_ptr++ * *mat++;
1031
1032 (*ch)[y] = sum;
1033 }
1034 }
1035 } else if (s->avctx->channels == 2) {
1036 int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
1037 s->fdsp.vector_fmul_scalar(ch_data[0] + sfb[0],
1038 ch_data[0] + sfb[0],
1039 181.0 / 128, len);
1040 s->fdsp.vector_fmul_scalar(ch_data[1] + sfb[0],
1041 ch_data[1] + sfb[0],
1042 181.0 / 128, len);
1043 }
1044 }
1045 }
1046 }
1047}
1048
1049/**
1050 *@brief Apply sine window and reconstruct the output buffer.
1051 *@param s codec context
1052 */
1053static void wmapro_window(WMAProDecodeCtx *s)
1054{
1055 int i;
1056 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1057 int c = s->channel_indexes_for_cur_subframe[i];
1058 const float* window;
1059 int winlen = s->channel[c].prev_block_len;
1060 float* start = s->channel[c].coeffs - (winlen >> 1);
1061
1062 if (s->subframe_len < winlen) {
1063 start += (winlen - s->subframe_len) >> 1;
1064 winlen = s->subframe_len;
1065 }
1066
1067 window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
1068
1069 winlen >>= 1;
1070
1071 s->fdsp.vector_fmul_window(start, start, start + winlen,
1072 window, winlen);
1073
1074 s->channel[c].prev_block_len = s->subframe_len;
1075 }
1076}
1077
1078/**
1079 *@brief Decode a single subframe (block).
1080 *@param s codec context
1081 *@return 0 on success, < 0 when decoding failed
1082 */
1083static int decode_subframe(WMAProDecodeCtx *s)
1084{
1085 int offset = s->samples_per_frame;
1086 int subframe_len = s->samples_per_frame;
1087 int i;
1088 int total_samples = s->samples_per_frame * s->avctx->channels;
1089 int transmit_coeffs = 0;
1090 int cur_subwoofer_cutoff;
1091
1092 s->subframe_offset = get_bits_count(&s->gb);
1093
1094 /** reset channel context and find the next block offset and size
1095 == the next block of the channel with the smallest number of
1096 decoded samples
1097 */
1098 for (i = 0; i < s->avctx->channels; i++) {
1099 s->channel[i].grouped = 0;
1100 if (offset > s->channel[i].decoded_samples) {
1101 offset = s->channel[i].decoded_samples;
1102 subframe_len =
1103 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1104 }
1105 }
1106
1107 av_dlog(s->avctx,
1108 "processing subframe with offset %i len %i\n", offset, subframe_len);
1109
1110 /** get a list of all channels that contain the estimated block */
1111 s->channels_for_cur_subframe = 0;
1112 for (i = 0; i < s->avctx->channels; i++) {
1113 const int cur_subframe = s->channel[i].cur_subframe;
1114 /** subtract already processed samples */
1115 total_samples -= s->channel[i].decoded_samples;
1116
1117 /** and count if there are multiple subframes that match our profile */
1118 if (offset == s->channel[i].decoded_samples &&
1119 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1120 total_samples -= s->channel[i].subframe_len[cur_subframe];
1121 s->channel[i].decoded_samples +=
1122 s->channel[i].subframe_len[cur_subframe];
1123 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1124 ++s->channels_for_cur_subframe;
1125 }
1126 }
1127
1128 /** check if the frame will be complete after processing the
1129 estimated block */
1130 if (!total_samples)
1131 s->parsed_all_subframes = 1;
1132
1133
1134 av_dlog(s->avctx, "subframe is part of %i channels\n",
1135 s->channels_for_cur_subframe);
1136
1137 /** calculate number of scale factor bands and their offsets */
1138 s->table_idx = av_log2(s->samples_per_frame/subframe_len);
1139 s->num_bands = s->num_sfb[s->table_idx];
1140 s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
1141 cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
1142
1143 /** configure the decoder for the current subframe */
1144 offset += s->samples_per_frame >> 1;
1145
1146 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1147 int c = s->channel_indexes_for_cur_subframe[i];
1148
1149 s->channel[c].coeffs = &s->channel[c].out[offset];
1150 }
1151
1152 s->subframe_len = subframe_len;
1153 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1154
1155 /** skip extended header if any */
1156 if (get_bits1(&s->gb)) {
1157 int num_fill_bits;
1158 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1159 int len = get_bits(&s->gb, 4);
1160 num_fill_bits = (len ? get_bits(&s->gb, len) : 0) + 1;
1161 }
1162
1163 if (num_fill_bits >= 0) {
1164 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1165 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1166 return AVERROR_INVALIDDATA;
1167 }
1168
1169 skip_bits_long(&s->gb, num_fill_bits);
1170 }
1171 }
1172
1173 /** no idea for what the following bit is used */
1174 if (get_bits1(&s->gb)) {
1175 avpriv_request_sample(s->avctx, "Reserved bit");
1176 return AVERROR_PATCHWELCOME;
1177 }
1178
1179
1180 if (decode_channel_transform(s) < 0)
1181 return AVERROR_INVALIDDATA;
1182
1183
1184 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1185 int c = s->channel_indexes_for_cur_subframe[i];
1186 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1187 transmit_coeffs = 1;
1188 }
1189
1190 av_assert0(s->subframe_len <= WMAPRO_BLOCK_MAX_SIZE);
1191 if (transmit_coeffs) {
1192 int step;
1193 int quant_step = 90 * s->bits_per_sample >> 4;
1194
1195 /** decode number of vector coded coefficients */
1196 if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
1197 int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
1198 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1199 int c = s->channel_indexes_for_cur_subframe[i];
1200 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
1201 if (num_vec_coeffs > s->subframe_len) {
1202 av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
1203 return AVERROR_INVALIDDATA;
1204 }
1205 av_assert0(num_vec_coeffs + offset <= FF_ARRAY_ELEMS(s->channel[c].out));
1206 s->channel[c].num_vec_coeffs = num_vec_coeffs;
1207 }
1208 } else {
1209 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1210 int c = s->channel_indexes_for_cur_subframe[i];
1211 s->channel[c].num_vec_coeffs = s->subframe_len;
1212 }
1213 }
1214 /** decode quantization step */
1215 step = get_sbits(&s->gb, 6);
1216 quant_step += step;
1217 if (step == -32 || step == 31) {
1218 const int sign = (step == 31) - 1;
1219 int quant = 0;
1220 while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
1221 (step = get_bits(&s->gb, 5)) == 31) {
1222 quant += 31;
1223 }
1224 quant_step += ((quant + step) ^ sign) - sign;
1225 }
1226 if (quant_step < 0) {
1227 av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
1228 }
1229
1230 /** decode quantization step modifiers for every channel */
1231
1232 if (s->channels_for_cur_subframe == 1) {
1233 s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
1234 } else {
1235 int modifier_len = get_bits(&s->gb, 3);
1236 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1237 int c = s->channel_indexes_for_cur_subframe[i];
1238 s->channel[c].quant_step = quant_step;
1239 if (get_bits1(&s->gb)) {
1240 if (modifier_len) {
1241 s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
1242 } else
1243 ++s->channel[c].quant_step;
1244 }
1245 }
1246 }
1247
1248 /** decode scale factors */
1249 if (decode_scale_factors(s) < 0)
1250 return AVERROR_INVALIDDATA;
1251 }
1252
1253 av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
1254 get_bits_count(&s->gb) - s->subframe_offset);
1255
1256 /** parse coefficients */
1257 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1258 int c = s->channel_indexes_for_cur_subframe[i];
1259 if (s->channel[c].transmit_coefs &&
1260 get_bits_count(&s->gb) < s->num_saved_bits) {
1261 decode_coeffs(s, c);
1262 } else
1263 memset(s->channel[c].coeffs, 0,
1264 sizeof(*s->channel[c].coeffs) * subframe_len);
1265 }
1266
1267 av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
1268 get_bits_count(&s->gb) - s->subframe_offset);
1269
1270 if (transmit_coeffs) {
1271 FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
1272 /** reconstruct the per channel data */
1273 inverse_channel_transform(s);
1274 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1275 int c = s->channel_indexes_for_cur_subframe[i];
1276 const int* sf = s->channel[c].scale_factors;
1277 int b;
1278
1279 if (c == s->lfe_channel)
1280 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
1281 (subframe_len - cur_subwoofer_cutoff));
1282
1283 /** inverse quantization and rescaling */
1284 for (b = 0; b < s->num_bands; b++) {
1285 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
1286 const int exp = s->channel[c].quant_step -
1287 (s->channel[c].max_scale_factor - *sf++) *
1288 s->channel[c].scale_factor_step;
1289 const float quant = pow(10.0, exp / 20.0);
1290 int start = s->cur_sfb_offsets[b];
1291 s->fdsp.vector_fmul_scalar(s->tmp + start,
1292 s->channel[c].coeffs + start,
1293 quant, end - start);
1294 }
1295
1296 /** apply imdct (imdct_half == DCTIV with reverse) */
1297 mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
1298 }
1299 }
1300
1301 /** window and overlapp-add */
1302 wmapro_window(s);
1303
1304 /** handled one subframe */
1305 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1306 int c = s->channel_indexes_for_cur_subframe[i];
1307 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1308 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1309 return AVERROR_INVALIDDATA;
1310 }
1311 ++s->channel[c].cur_subframe;
1312 }
1313
1314 return 0;
1315}
1316
1317/**
1318 *@brief Decode one WMA frame.
1319 *@param s codec context
1320 *@return 0 if the trailer bit indicates that this is the last frame,
1321 * 1 if there are additional frames
1322 */
1323static int decode_frame(WMAProDecodeCtx *s, AVFrame *frame, int *got_frame_ptr)
1324{
1325 AVCodecContext *avctx = s->avctx;
1326 GetBitContext* gb = &s->gb;
1327 int more_frames = 0;
1328 int len = 0;
1329 int i, ret;
1330
1331 /** get frame length */
1332 if (s->len_prefix)
1333 len = get_bits(gb, s->log2_frame_size);
1334
1335 av_dlog(s->avctx, "decoding frame with length %x\n", len);
1336
1337 /** decode tile information */
1338 if (decode_tilehdr(s)) {
1339 s->packet_loss = 1;
1340 return 0;
1341 }
1342
1343 /** read postproc transform */
1344 if (s->avctx->channels > 1 && get_bits1(gb)) {
1345 if (get_bits1(gb)) {
1346 for (i = 0; i < avctx->channels * avctx->channels; i++)
1347 skip_bits(gb, 4);
1348 }
1349 }
1350
1351 /** read drc info */
1352 if (s->dynamic_range_compression) {
1353 s->drc_gain = get_bits(gb, 8);
1354 av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
1355 }
1356
1357 /** no idea what these are for, might be the number of samples
1358 that need to be skipped at the beginning or end of a stream */
1359 if (get_bits1(gb)) {
1360 int av_unused skip;
1361
1362 /** usually true for the first frame */
1363 if (get_bits1(gb)) {
1364 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1365 av_dlog(s->avctx, "start skip: %i\n", skip);
1366 }
1367
1368 /** sometimes true for the last frame */
1369 if (get_bits1(gb)) {
1370 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1371 av_dlog(s->avctx, "end skip: %i\n", skip);
1372 }
1373
1374 }
1375
1376 av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
1377 get_bits_count(gb) - s->frame_offset);
1378
1379 /** reset subframe states */
1380 s->parsed_all_subframes = 0;
1381 for (i = 0; i < avctx->channels; i++) {
1382 s->channel[i].decoded_samples = 0;
1383 s->channel[i].cur_subframe = 0;
1384 s->channel[i].reuse_sf = 0;
1385 }
1386
1387 /** decode all subframes */
1388 while (!s->parsed_all_subframes) {
1389 if (decode_subframe(s) < 0) {
1390 s->packet_loss = 1;
1391 return 0;
1392 }
1393 }
1394
1395 /* get output buffer */
1396 frame->nb_samples = s->samples_per_frame;
1397 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
1398 s->packet_loss = 1;
1399 return 0;
1400 }
1401
1402 /** copy samples to the output buffer */
1403 for (i = 0; i < avctx->channels; i++)
1404 memcpy(frame->extended_data[i], s->channel[i].out,
1405 s->samples_per_frame * sizeof(*s->channel[i].out));
1406
1407 for (i = 0; i < avctx->channels; i++) {
1408 /** reuse second half of the IMDCT output for the next frame */
1409 memcpy(&s->channel[i].out[0],
1410 &s->channel[i].out[s->samples_per_frame],
1411 s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
1412 }
1413
1414 if (s->skip_frame) {
1415 s->skip_frame = 0;
1416 *got_frame_ptr = 0;
1417 av_frame_unref(frame);
1418 } else {
1419 *got_frame_ptr = 1;
1420 }
1421
1422 if (s->len_prefix) {
1423 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1424 /** FIXME: not sure if this is always an error */
1425 av_log(s->avctx, AV_LOG_ERROR,
1426 "frame[%"PRIu32"] would have to skip %i bits\n",
1427 s->frame_num,
1428 len - (get_bits_count(gb) - s->frame_offset) - 1);
1429 s->packet_loss = 1;
1430 return 0;
1431 }
1432
1433 /** skip the rest of the frame data */
1434 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1435 } else {
1436 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1437 }
1438 }
1439
1440 /** decode trailer bit */
1441 more_frames = get_bits1(gb);
1442
1443 ++s->frame_num;
1444 return more_frames;
1445}
1446
1447/**
1448 *@brief Calculate remaining input buffer length.
1449 *@param s codec context
1450 *@param gb bitstream reader context
1451 *@return remaining size in bits
1452 */
1453static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1454{
1455 return s->buf_bit_size - get_bits_count(gb);
1456}
1457
1458/**
1459 *@brief Fill the bit reservoir with a (partial) frame.
1460 *@param s codec context
1461 *@param gb bitstream reader context
1462 *@param len length of the partial frame
1463 *@param append decides whether to reset the buffer or not
1464 */
1465static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1466 int append)
1467{
1468 int buflen;
1469
1470 /** when the frame data does not need to be concatenated, the input buffer
1471 is reset and additional bits from the previous frame are copied
1472 and skipped later so that a fast byte copy is possible */
1473
1474 if (!append) {
1475 s->frame_offset = get_bits_count(gb) & 7;
1476 s->num_saved_bits = s->frame_offset;
1477 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1478 }
1479
1480 buflen = (put_bits_count(&s->pb) + len + 8) >> 3;
1481
1482 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1483 avpriv_request_sample(s->avctx, "Too small input buffer");
1484 s->packet_loss = 1;
1485 return;
1486 }
1487
1488 av_assert0(len <= put_bits_left(&s->pb));
1489
1490 s->num_saved_bits += len;
1491 if (!append) {
1492 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1493 s->num_saved_bits);
1494 } else {
1495 int align = 8 - (get_bits_count(gb) & 7);
1496 align = FFMIN(align, len);
1497 put_bits(&s->pb, align, get_bits(gb, align));
1498 len -= align;
1499 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1500 }
1501 skip_bits_long(gb, len);
1502
1503 {
1504 PutBitContext tmp = s->pb;
1505 flush_put_bits(&tmp);
1506 }
1507
1508 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1509 skip_bits(&s->gb, s->frame_offset);
1510}
1511
1512/**
1513 *@brief Decode a single WMA packet.
1514 *@param avctx codec context
1515 *@param data the output buffer
1516 *@param avpkt input packet
1517 *@return number of bytes that were read from the input buffer
1518 */
1519static int decode_packet(AVCodecContext *avctx, void *data,
1520 int *got_frame_ptr, AVPacket* avpkt)
1521{
1522 WMAProDecodeCtx *s = avctx->priv_data;
1523 GetBitContext* gb = &s->pgb;
1524 const uint8_t* buf = avpkt->data;
1525 int buf_size = avpkt->size;
1526 int num_bits_prev_frame;
1527 int packet_sequence_number;
1528
1529 *got_frame_ptr = 0;
1530
1531 if (s->packet_done || s->packet_loss) {
1532 s->packet_done = 0;
1533
1534 /** sanity check for the buffer length */
1535 if (buf_size < avctx->block_align) {
1536 av_log(avctx, AV_LOG_ERROR, "Input packet too small (%d < %d)\n",
1537 buf_size, avctx->block_align);
1538 return AVERROR_INVALIDDATA;
1539 }
1540
1541 s->next_packet_start = buf_size - avctx->block_align;
1542 buf_size = avctx->block_align;
1543 s->buf_bit_size = buf_size << 3;
1544
1545 /** parse packet header */
1546 init_get_bits(gb, buf, s->buf_bit_size);
1547 packet_sequence_number = get_bits(gb, 4);
1548 skip_bits(gb, 2);
1549
1550 /** get number of bits that need to be added to the previous frame */
1551 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1552 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1553 num_bits_prev_frame);
1554
1555 /** check for packet loss */
1556 if (!s->packet_loss &&
1557 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1558 s->packet_loss = 1;
1559 av_log(avctx, AV_LOG_ERROR,
1560 "Packet loss detected! seq %"PRIx8" vs %x\n",
1561 s->packet_sequence_number, packet_sequence_number);
1562 }
1563 s->packet_sequence_number = packet_sequence_number;
1564
1565 if (num_bits_prev_frame > 0) {
1566 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1567 if (num_bits_prev_frame >= remaining_packet_bits) {
1568 num_bits_prev_frame = remaining_packet_bits;
1569 s->packet_done = 1;
1570 }
1571
1572 /** append the previous frame data to the remaining data from the
1573 previous packet to create a full frame */
1574 save_bits(s, gb, num_bits_prev_frame, 1);
1575 av_dlog(avctx, "accumulated %x bits of frame data\n",
1576 s->num_saved_bits - s->frame_offset);
1577
1578 /** decode the cross packet frame if it is valid */
1579 if (!s->packet_loss)
1580 decode_frame(s, data, got_frame_ptr);
1581 } else if (s->num_saved_bits - s->frame_offset) {
1582 av_dlog(avctx, "ignoring %x previously saved bits\n",
1583 s->num_saved_bits - s->frame_offset);
1584 }
1585
1586 if (s->packet_loss) {
1587 /** reset number of saved bits so that the decoder
1588 does not start to decode incomplete frames in the
1589 s->len_prefix == 0 case */
1590 s->num_saved_bits = 0;
1591 s->packet_loss = 0;
1592 }
1593
1594 } else {
1595 int frame_size;
1596 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1597 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1598 skip_bits(gb, s->packet_offset);
1599 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1600 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1601 frame_size <= remaining_bits(s, gb)) {
1602 save_bits(s, gb, frame_size, 0);
1603 if (!s->packet_loss)
1604 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1605 } else if (!s->len_prefix
1606 && s->num_saved_bits > get_bits_count(&s->gb)) {
1607 /** when the frames do not have a length prefix, we don't know
1608 the compressed length of the individual frames
1609 however, we know what part of a new packet belongs to the
1610 previous frame
1611 therefore we save the incoming packet first, then we append
1612 the "previous frame" data from the next packet so that
1613 we get a buffer that only contains full frames */
1614 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1615 } else
1616 s->packet_done = 1;
1617 }
1618
1619 if (s->packet_done && !s->packet_loss &&
1620 remaining_bits(s, gb) > 0) {
1621 /** save the rest of the data so that it can be decoded
1622 with the next packet */
1623 save_bits(s, gb, remaining_bits(s, gb), 0);
1624 }
1625
1626 s->packet_offset = get_bits_count(gb) & 7;
1627 if (s->packet_loss)
1628 return AVERROR_INVALIDDATA;
1629
1630 return get_bits_count(gb) >> 3;
1631}
1632
1633/**
1634 *@brief Clear decoder buffers (for seeking).
1635 *@param avctx codec context
1636 */
1637static void flush(AVCodecContext *avctx)
1638{
1639 WMAProDecodeCtx *s = avctx->priv_data;
1640 int i;
1641 /** reset output buffer as a part of it is used during the windowing of a
1642 new frame */
1643 for (i = 0; i < avctx->channels; i++)
1644 memset(s->channel[i].out, 0, s->samples_per_frame *
1645 sizeof(*s->channel[i].out));
1646 s->packet_loss = 1;
1647}
1648
1649
1650/**
1651 *@brief wmapro decoder
1652 */
1653AVCodec ff_wmapro_decoder = {
1654 .name = "wmapro",
1655 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1656 .type = AVMEDIA_TYPE_AUDIO,
1657 .id = AV_CODEC_ID_WMAPRO,
1658 .priv_data_size = sizeof(WMAProDecodeCtx),
1659 .init = decode_init,
1660 .close = decode_end,
1661 .decode = decode_packet,
1662 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1663 .flush = flush,
1664 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1665 AV_SAMPLE_FMT_NONE },
1666};
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