2 * Wmapro compatible decoder
3 * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
4 * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
6 * This file is part of FFmpeg.
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.
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.
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
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
32 * - windowing and overlapp-add
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
40 * The number of samples and a few other decode flags are stored
41 * as extradata that has to be passed to the decoder.
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.
47 * Example wmapro bitstream (in samples):
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 * ---------------------------------------------------
58 * The frame layouts for the individual channels of a wma frame does not need
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.
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
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
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.
89 #include "libavutil/float_dsp.h"
90 #include "libavutil/intfloat.h"
91 #include "libavutil/intreadwrite.h"
96 #include "wmaprodata.h"
99 #include "wma_common.h"
101 /** current decoder limitations */
102 #define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels
103 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
104 #define MAX_BANDS 29 ///< max number of scale factor bands
105 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
107 #define WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
108 #define WMAPRO_BLOCK_MAX_BITS 13 ///< log2 of max block size
109 #define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size
110 #define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
114 #define SCALEVLCBITS 8
115 #define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
116 #define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
117 #define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
118 #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
119 #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
121 static VLC sf_vlc; ///< scale factor DPCM vlc
122 static VLC sf_rl_vlc; ///< scale factor run length vlc
123 static VLC vec4_vlc; ///< 4 coefficients per symbol
124 static VLC vec2_vlc; ///< 2 coefficients per symbol
125 static VLC vec1_vlc; ///< 1 coefficient per symbol
126 static VLC coef_vlc[2]; ///< coefficient run length vlc codes
127 static float sin64[33]; ///< sinus table for decorrelation
130 * @brief frame specific decoder context for a single channel
133 int16_t prev_block_len; ///< length of the previous block
134 uint8_t transmit_coefs;
135 uint8_t num_subframes;
136 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
137 uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
138 uint8_t cur_subframe; ///< current subframe number
139 uint16_t decoded_samples; ///< number of already processed samples
140 uint8_t grouped; ///< channel is part of a group
141 int quant_step; ///< quantization step for the current subframe
142 int8_t reuse_sf; ///< share scale factors between subframes
143 int8_t scale_factor_step; ///< scaling step for the current subframe
144 int max_scale_factor; ///< maximum scale factor for the current subframe
145 int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
146 int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
147 int* scale_factors; ///< pointer to the scale factor values used for decoding
148 uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
149 float* coeffs; ///< pointer to the subframe decode buffer
150 uint16_t num_vec_coeffs; ///< number of vector coded coefficients
151 DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer
155 * @brief channel group for channel transformations
158 uint8_t num_channels; ///< number of channels in the group
159 int8_t transform; ///< transform on / off
160 int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
161 float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
162 float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients
166 * @brief main decoder context
168 typedef struct WMAProDecodeCtx {
169 /* generic decoder variables */
170 AVCodecContext* avctx; ///< codec context for av_log
171 AVFloatDSPContext fdsp;
172 uint8_t frame_data[MAX_FRAMESIZE +
173 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
174 PutBitContext pb; ///< context for filling the frame_data buffer
175 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
176 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
177 float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
179 /* frame size dependent frame information (set during initialization) */
180 uint32_t decode_flags; ///< used compression features
181 uint8_t len_prefix; ///< frame is prefixed with its length
182 uint8_t dynamic_range_compression; ///< frame contains DRC data
183 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
184 uint16_t samples_per_frame; ///< number of samples to output
185 uint16_t log2_frame_size;
186 int8_t lfe_channel; ///< lfe channel index
187 uint8_t max_num_subframes;
188 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
189 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
190 uint16_t min_samples_per_subframe;
191 int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
192 int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
193 int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
194 int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
196 /* packet decode state */
197 GetBitContext pgb; ///< bitstream reader context for the packet
198 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
199 uint8_t packet_offset; ///< frame offset in the packet
200 uint8_t packet_sequence_number; ///< current packet number
201 int num_saved_bits; ///< saved number of bits
202 int frame_offset; ///< frame offset in the bit reservoir
203 int subframe_offset; ///< subframe offset in the bit reservoir
204 uint8_t packet_loss; ///< set in case of bitstream error
205 uint8_t packet_done; ///< set when a packet is fully decoded
207 /* frame decode state */
208 uint32_t frame_num; ///< current frame number (not used for decoding)
209 GetBitContext gb; ///< bitstream reader context
210 int buf_bit_size; ///< buffer size in bits
211 uint8_t drc_gain; ///< gain for the DRC tool
212 int8_t skip_frame; ///< skip output step
213 int8_t parsed_all_subframes; ///< all subframes decoded?
215 /* subframe/block decode state */
216 int16_t subframe_len; ///< current subframe length
217 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
218 int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
219 int8_t num_bands; ///< number of scale factor bands
220 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
221 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
222 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
223 int8_t esc_len; ///< length of escaped coefficients
225 uint8_t num_chgroups; ///< number of channel groups
226 WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
228 WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
233 *@brief helper function to print the most important members of the context
236 static av_cold void dump_context(WMAProDecodeCtx *s)
238 #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
239 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
241 PRINT("ed sample bit depth", s->bits_per_sample);
242 PRINT_HEX("ed decode flags", s->decode_flags);
243 PRINT("samples per frame", s->samples_per_frame);
244 PRINT("log2 frame size", s->log2_frame_size);
245 PRINT("max num subframes", s->max_num_subframes);
246 PRINT("len prefix", s->len_prefix);
247 PRINT("num channels", s->avctx->channels);
251 *@brief Uninitialize the decoder and free all resources.
252 *@param avctx codec context
253 *@return 0 on success, < 0 otherwise
255 static av_cold int decode_end(AVCodecContext *avctx)
257 WMAProDecodeCtx *s = avctx->priv_data;
260 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
261 ff_mdct_end(&s->mdct_ctx[i]);
267 *@brief Initialize the decoder.
268 *@param avctx codec context
269 *@return 0 on success, -1 otherwise
271 static av_cold int decode_init(AVCodecContext *avctx)
273 WMAProDecodeCtx *s = avctx->priv_data;
274 uint8_t *edata_ptr = avctx->extradata;
275 unsigned int channel_mask;
277 int log2_max_num_subframes;
278 int num_possible_block_sizes;
280 if (!avctx->block_align) {
281 av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
282 return AVERROR(EINVAL);
286 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
288 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
290 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
292 if (avctx->extradata_size >= 18) {
293 s->decode_flags = AV_RL16(edata_ptr+14);
294 channel_mask = AV_RL32(edata_ptr+2);
295 s->bits_per_sample = AV_RL16(edata_ptr);
296 /** dump the extradata */
297 for (i = 0; i < avctx->extradata_size; i++)
298 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
299 av_dlog(avctx, "\n");
302 avpriv_request_sample(avctx, "Unknown extradata size");
303 return AVERROR_PATCHWELCOME;
307 s->log2_frame_size = av_log2(avctx->block_align) + 4;
310 s->skip_frame = 1; /* skip first frame */
312 s->len_prefix = (s->decode_flags & 0x40);
315 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
316 if (bits > WMAPRO_BLOCK_MAX_BITS) {
317 avpriv_request_sample(avctx, "14-bit block sizes");
318 return AVERROR_PATCHWELCOME;
320 s->samples_per_frame = 1 << bits;
323 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
324 s->max_num_subframes = 1 << log2_max_num_subframes;
325 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
326 s->max_subframe_len_bit = 1;
327 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
329 num_possible_block_sizes = log2_max_num_subframes + 1;
330 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
331 s->dynamic_range_compression = (s->decode_flags & 0x80);
333 if (s->max_num_subframes > MAX_SUBFRAMES) {
334 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
335 s->max_num_subframes);
336 return AVERROR_INVALIDDATA;
339 if (s->min_samples_per_subframe < (1<<WMAPRO_BLOCK_MIN_BITS)) {
340 av_log(avctx, AV_LOG_ERROR, "min_samples_per_subframe of %d too small\n",
341 s->min_samples_per_subframe);
342 return AVERROR_INVALIDDATA;
345 if (s->avctx->sample_rate <= 0) {
346 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
347 return AVERROR_INVALIDDATA;
350 if (avctx->channels < 0) {
351 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
353 return AVERROR_INVALIDDATA;
354 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
355 avpriv_request_sample(avctx,
356 "More than %d channels", WMAPRO_MAX_CHANNELS);
357 return AVERROR_PATCHWELCOME;
360 /** init previous block len */
361 for (i = 0; i < avctx->channels; i++)
362 s->channel[i].prev_block_len = s->samples_per_frame;
364 /** extract lfe channel position */
367 if (channel_mask & 8) {
369 for (mask = 1; mask < 16; mask <<= 1) {
370 if (channel_mask & mask)
375 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
376 scale_huffbits, 1, 1,
377 scale_huffcodes, 2, 2, 616);
379 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
380 scale_rl_huffbits, 1, 1,
381 scale_rl_huffcodes, 4, 4, 1406);
383 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
384 coef0_huffbits, 1, 1,
385 coef0_huffcodes, 4, 4, 2108);
387 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
388 coef1_huffbits, 1, 1,
389 coef1_huffcodes, 4, 4, 3912);
391 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
393 vec4_huffcodes, 2, 2, 604);
395 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
397 vec2_huffcodes, 2, 2, 562);
399 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
401 vec1_huffcodes, 2, 2, 562);
403 /** calculate number of scale factor bands and their offsets
404 for every possible block size */
405 for (i = 0; i < num_possible_block_sizes; i++) {
406 int subframe_len = s->samples_per_frame >> i;
410 s->sfb_offsets[i][0] = 0;
412 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
413 int offset = (subframe_len * 2 * critical_freq[x])
414 / s->avctx->sample_rate + 2;
416 if (offset > s->sfb_offsets[i][band - 1])
417 s->sfb_offsets[i][band++] = offset;
419 s->sfb_offsets[i][band - 1] = subframe_len;
420 s->num_sfb[i] = band - 1;
421 if (s->num_sfb[i] <= 0) {
422 av_log(avctx, AV_LOG_ERROR, "num_sfb invalid\n");
423 return AVERROR_INVALIDDATA;
428 /** Scale factors can be shared between blocks of different size
429 as every block has a different scale factor band layout.
430 The matrix sf_offsets is needed to find the correct scale factor.
433 for (i = 0; i < num_possible_block_sizes; i++) {
435 for (b = 0; b < s->num_sfb[i]; b++) {
437 int offset = ((s->sfb_offsets[i][b]
438 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
439 for (x = 0; x < num_possible_block_sizes; x++) {
441 while (s->sfb_offsets[x][v + 1] << x < offset)
443 s->sf_offsets[i][x][b] = v;
448 /** init MDCT, FIXME: only init needed sizes */
449 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
450 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
451 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
452 / (1 << (s->bits_per_sample - 1)));
454 /** init MDCT windows: simple sinus window */
455 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
456 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
457 ff_init_ff_sine_windows(win_idx);
458 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
461 /** calculate subwoofer cutoff values */
462 for (i = 0; i < num_possible_block_sizes; i++) {
463 int block_size = s->samples_per_frame >> i;
464 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
465 / s->avctx->sample_rate;
466 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
469 /** calculate sine values for the decorrelation matrix */
470 for (i = 0; i < 33; i++)
471 sin64[i] = sin(i*M_PI / 64.0);
473 if (avctx->debug & FF_DEBUG_BITSTREAM)
476 avctx->channel_layout = channel_mask;
482 *@brief Decode the subframe length.
484 *@param offset sample offset in the frame
485 *@return decoded subframe length on success, < 0 in case of an error
487 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
489 int frame_len_shift = 0;
492 /** no need to read from the bitstream when only one length is possible */
493 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
494 return s->min_samples_per_subframe;
496 /** 1 bit indicates if the subframe is of maximum length */
497 if (s->max_subframe_len_bit) {
498 if (get_bits1(&s->gb))
499 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
501 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
503 subframe_len = s->samples_per_frame >> frame_len_shift;
505 /** sanity check the length */
506 if (subframe_len < s->min_samples_per_subframe ||
507 subframe_len > s->samples_per_frame) {
508 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
510 return AVERROR_INVALIDDATA;
516 *@brief Decode how the data in the frame is split into subframes.
517 * Every WMA frame contains the encoded data for a fixed number of
518 * samples per channel. The data for every channel might be split
519 * into several subframes. This function will reconstruct the list of
520 * subframes for every channel.
522 * If the subframes are not evenly split, the algorithm estimates the
523 * channels with the lowest number of total samples.
524 * Afterwards, for each of these channels a bit is read from the
525 * bitstream that indicates if the channel contains a subframe with the
526 * next subframe size that is going to be read from the bitstream or not.
527 * If a channel contains such a subframe, the subframe size gets added to
528 * the channel's subframe list.
529 * The algorithm repeats these steps until the frame is properly divided
530 * between the individual channels.
533 *@return 0 on success, < 0 in case of an error
535 static int decode_tilehdr(WMAProDecodeCtx *s)
537 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
538 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
539 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
540 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
541 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
544 /* Should never consume more than 3073 bits (256 iterations for the
545 * while loop when always the minimum amount of 128 samples is subtracted
546 * from missing samples in the 8 channel case).
547 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
550 /** reset tiling information */
551 for (c = 0; c < s->avctx->channels; c++)
552 s->channel[c].num_subframes = 0;
554 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
555 fixed_channel_layout = 1;
557 /** loop until the frame data is split between the subframes */
561 /** check which channels contain the subframe */
562 for (c = 0; c < s->avctx->channels; c++) {
563 if (num_samples[c] == min_channel_len) {
564 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
565 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
566 contains_subframe[c] = 1;
568 contains_subframe[c] = get_bits1(&s->gb);
570 contains_subframe[c] = 0;
573 /** get subframe length, subframe_len == 0 is not allowed */
574 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
575 return AVERROR_INVALIDDATA;
577 /** add subframes to the individual channels and find new min_channel_len */
578 min_channel_len += subframe_len;
579 for (c = 0; c < s->avctx->channels; c++) {
580 WMAProChannelCtx* chan = &s->channel[c];
582 if (contains_subframe[c]) {
583 if (chan->num_subframes >= MAX_SUBFRAMES) {
584 av_log(s->avctx, AV_LOG_ERROR,
585 "broken frame: num subframes > 31\n");
586 return AVERROR_INVALIDDATA;
588 chan->subframe_len[chan->num_subframes] = subframe_len;
589 num_samples[c] += subframe_len;
590 ++chan->num_subframes;
591 if (num_samples[c] > s->samples_per_frame) {
592 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
593 "channel len > samples_per_frame\n");
594 return AVERROR_INVALIDDATA;
596 } else if (num_samples[c] <= min_channel_len) {
597 if (num_samples[c] < min_channel_len) {
598 channels_for_cur_subframe = 0;
599 min_channel_len = num_samples[c];
601 ++channels_for_cur_subframe;
604 } while (min_channel_len < s->samples_per_frame);
606 for (c = 0; c < s->avctx->channels; c++) {
609 for (i = 0; i < s->channel[c].num_subframes; i++) {
610 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
611 " len %i\n", s->frame_num, c, i,
612 s->channel[c].subframe_len[i]);
613 s->channel[c].subframe_offset[i] = offset;
614 offset += s->channel[c].subframe_len[i];
622 *@brief Calculate a decorrelation matrix from the bitstream parameters.
623 *@param s codec context
624 *@param chgroup channel group for which the matrix needs to be calculated
626 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
627 WMAProChannelGrp *chgroup)
631 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
632 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
633 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
635 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
636 rotation_offset[i] = get_bits(&s->gb, 6);
638 for (i = 0; i < chgroup->num_channels; i++)
639 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
640 get_bits1(&s->gb) ? 1.0 : -1.0;
642 for (i = 1; i < chgroup->num_channels; i++) {
644 for (x = 0; x < i; x++) {
646 for (y = 0; y < i + 1; y++) {
647 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
648 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
649 int n = rotation_offset[offset + x];
655 cosv = sin64[32 - n];
657 sinv = sin64[64 - n];
658 cosv = -sin64[n - 32];
661 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
662 (v1 * sinv) - (v2 * cosv);
663 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
664 (v1 * cosv) + (v2 * sinv);
672 *@brief Decode channel transformation parameters
673 *@param s codec context
674 *@return 0 in case of success, < 0 in case of bitstream errors
676 static int decode_channel_transform(WMAProDecodeCtx* s)
679 /* should never consume more than 1921 bits for the 8 channel case
680 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
681 * + MAX_CHANNELS + MAX_BANDS + 1)
684 /** in the one channel case channel transforms are pointless */
686 if (s->avctx->channels > 1) {
687 int remaining_channels = s->channels_for_cur_subframe;
689 if (get_bits1(&s->gb)) {
690 avpriv_request_sample(s->avctx,
691 "Channel transform bit");
692 return AVERROR_PATCHWELCOME;
695 for (s->num_chgroups = 0; remaining_channels &&
696 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
697 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
698 float** channel_data = chgroup->channel_data;
699 chgroup->num_channels = 0;
700 chgroup->transform = 0;
702 /** decode channel mask */
703 if (remaining_channels > 2) {
704 for (i = 0; i < s->channels_for_cur_subframe; i++) {
705 int channel_idx = s->channel_indexes_for_cur_subframe[i];
706 if (!s->channel[channel_idx].grouped
707 && get_bits1(&s->gb)) {
708 ++chgroup->num_channels;
709 s->channel[channel_idx].grouped = 1;
710 *channel_data++ = s->channel[channel_idx].coeffs;
714 chgroup->num_channels = remaining_channels;
715 for (i = 0; i < s->channels_for_cur_subframe; i++) {
716 int channel_idx = s->channel_indexes_for_cur_subframe[i];
717 if (!s->channel[channel_idx].grouped)
718 *channel_data++ = s->channel[channel_idx].coeffs;
719 s->channel[channel_idx].grouped = 1;
723 /** decode transform type */
724 if (chgroup->num_channels == 2) {
725 if (get_bits1(&s->gb)) {
726 if (get_bits1(&s->gb)) {
727 avpriv_request_sample(s->avctx,
728 "Unknown channel transform type");
731 chgroup->transform = 1;
732 if (s->avctx->channels == 2) {
733 chgroup->decorrelation_matrix[0] = 1.0;
734 chgroup->decorrelation_matrix[1] = -1.0;
735 chgroup->decorrelation_matrix[2] = 1.0;
736 chgroup->decorrelation_matrix[3] = 1.0;
739 chgroup->decorrelation_matrix[0] = 0.70703125;
740 chgroup->decorrelation_matrix[1] = -0.70703125;
741 chgroup->decorrelation_matrix[2] = 0.70703125;
742 chgroup->decorrelation_matrix[3] = 0.70703125;
745 } else if (chgroup->num_channels > 2) {
746 if (get_bits1(&s->gb)) {
747 chgroup->transform = 1;
748 if (get_bits1(&s->gb)) {
749 decode_decorrelation_matrix(s, chgroup);
751 /** FIXME: more than 6 coupled channels not supported */
752 if (chgroup->num_channels > 6) {
753 avpriv_request_sample(s->avctx,
754 "Coupled channels > 6");
756 memcpy(chgroup->decorrelation_matrix,
757 default_decorrelation[chgroup->num_channels],
758 chgroup->num_channels * chgroup->num_channels *
759 sizeof(*chgroup->decorrelation_matrix));
765 /** decode transform on / off */
766 if (chgroup->transform) {
767 if (!get_bits1(&s->gb)) {
769 /** transform can be enabled for individual bands */
770 for (i = 0; i < s->num_bands; i++) {
771 chgroup->transform_band[i] = get_bits1(&s->gb);
774 memset(chgroup->transform_band, 1, s->num_bands);
777 remaining_channels -= chgroup->num_channels;
784 *@brief Extract the coefficients from the bitstream.
785 *@param s codec context
786 *@param c current channel number
787 *@return 0 on success, < 0 in case of bitstream errors
789 static int decode_coeffs(WMAProDecodeCtx *s, int c)
791 /* Integers 0..15 as single-precision floats. The table saves a
792 costly int to float conversion, and storing the values as
793 integers allows fast sign-flipping. */
794 static const uint32_t fval_tab[16] = {
795 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
796 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
797 0x41000000, 0x41100000, 0x41200000, 0x41300000,
798 0x41400000, 0x41500000, 0x41600000, 0x41700000,
802 WMAProChannelCtx* ci = &s->channel[c];
809 av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
811 vlctable = get_bits1(&s->gb);
812 vlc = &coef_vlc[vlctable];
822 /** decode vector coefficients (consumes up to 167 bits per iteration for
823 4 vector coded large values) */
824 while ((s->transmit_num_vec_coeffs || !rl_mode) &&
825 (cur_coeff + 3 < ci->num_vec_coeffs)) {
830 idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
832 if (idx == HUFF_VEC4_SIZE - 1) {
833 for (i = 0; i < 4; i += 2) {
834 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
835 if (idx == HUFF_VEC2_SIZE - 1) {
837 v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
838 if (v0 == HUFF_VEC1_SIZE - 1)
839 v0 += ff_wma_get_large_val(&s->gb);
840 v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
841 if (v1 == HUFF_VEC1_SIZE - 1)
842 v1 += ff_wma_get_large_val(&s->gb);
843 vals[i ] = av_float2int(v0);
844 vals[i+1] = av_float2int(v1);
846 vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
847 vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
851 vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
852 vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
853 vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
854 vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
858 for (i = 0; i < 4; i++) {
860 uint32_t sign = get_bits1(&s->gb) - 1;
861 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
864 ci->coeffs[cur_coeff] = 0;
865 /** switch to run level mode when subframe_len / 128 zeros
866 were found in a row */
867 rl_mode |= (++num_zeros > s->subframe_len >> 8);
873 /** decode run level coded coefficients */
874 if (cur_coeff < s->subframe_len) {
875 memset(&ci->coeffs[cur_coeff], 0,
876 sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
877 if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
878 level, run, 1, ci->coeffs,
879 cur_coeff, s->subframe_len,
880 s->subframe_len, s->esc_len, 0))
881 return AVERROR_INVALIDDATA;
888 *@brief Extract scale factors from the bitstream.
889 *@param s codec context
890 *@return 0 on success, < 0 in case of bitstream errors
892 static int decode_scale_factors(WMAProDecodeCtx* s)
896 /** should never consume more than 5344 bits
897 * MAX_CHANNELS * (1 + MAX_BANDS * 23)
900 for (i = 0; i < s->channels_for_cur_subframe; i++) {
901 int c = s->channel_indexes_for_cur_subframe[i];
904 s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
905 sf_end = s->channel[c].scale_factors + s->num_bands;
907 /** resample scale factors for the new block size
908 * as the scale factors might need to be resampled several times
909 * before some new values are transmitted, a backup of the last
910 * transmitted scale factors is kept in saved_scale_factors
912 if (s->channel[c].reuse_sf) {
913 const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
915 for (b = 0; b < s->num_bands; b++)
916 s->channel[c].scale_factors[b] =
917 s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
920 if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
922 if (!s->channel[c].reuse_sf) {
924 /** decode DPCM coded scale factors */
925 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
926 val = 45 / s->channel[c].scale_factor_step;
927 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
928 val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
933 /** run level decode differences to the resampled factors */
934 for (i = 0; i < s->num_bands; i++) {
940 idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
943 uint32_t code = get_bits(&s->gb, 14);
945 sign = (code & 1) - 1;
946 skip = (code & 0x3f) >> 1;
947 } else if (idx == 1) {
950 skip = scale_rl_run[idx];
951 val = scale_rl_level[idx];
952 sign = get_bits1(&s->gb)-1;
956 if (i >= s->num_bands) {
957 av_log(s->avctx, AV_LOG_ERROR,
958 "invalid scale factor coding\n");
959 return AVERROR_INVALIDDATA;
961 s->channel[c].scale_factors[i] += (val ^ sign) - sign;
965 s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
966 s->channel[c].table_idx = s->table_idx;
967 s->channel[c].reuse_sf = 1;
970 /** calculate new scale factor maximum */
971 s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
972 for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
973 s->channel[c].max_scale_factor =
974 FFMAX(s->channel[c].max_scale_factor, *sf);
982 *@brief Reconstruct the individual channel data.
983 *@param s codec context
985 static void inverse_channel_transform(WMAProDecodeCtx *s)
989 for (i = 0; i < s->num_chgroups; i++) {
990 if (s->chgroup[i].transform) {
991 float data[WMAPRO_MAX_CHANNELS];
992 const int num_channels = s->chgroup[i].num_channels;
993 float** ch_data = s->chgroup[i].channel_data;
994 float** ch_end = ch_data + num_channels;
995 const int8_t* tb = s->chgroup[i].transform_band;
998 /** multichannel decorrelation */
999 for (sfb = s->cur_sfb_offsets;
1000 sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
1003 /** multiply values with the decorrelation_matrix */
1004 for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
1005 const float* mat = s->chgroup[i].decorrelation_matrix;
1006 const float* data_end = data + num_channels;
1007 float* data_ptr = data;
1010 for (ch = ch_data; ch < ch_end; ch++)
1011 *data_ptr++ = (*ch)[y];
1013 for (ch = ch_data; ch < ch_end; ch++) {
1016 while (data_ptr < data_end)
1017 sum += *data_ptr++ * *mat++;
1022 } else if (s->avctx->channels == 2) {
1023 int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
1024 s->fdsp.vector_fmul_scalar(ch_data[0] + sfb[0],
1025 ch_data[0] + sfb[0],
1027 s->fdsp.vector_fmul_scalar(ch_data[1] + sfb[0],
1028 ch_data[1] + sfb[0],
1037 *@brief Apply sine window and reconstruct the output buffer.
1038 *@param s codec context
1040 static void wmapro_window(WMAProDecodeCtx *s)
1043 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1044 int c = s->channel_indexes_for_cur_subframe[i];
1046 int winlen = s->channel[c].prev_block_len;
1047 float* start = s->channel[c].coeffs - (winlen >> 1);
1049 if (s->subframe_len < winlen) {
1050 start += (winlen - s->subframe_len) >> 1;
1051 winlen = s->subframe_len;
1054 window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
1058 s->fdsp.vector_fmul_window(start, start, start + winlen,
1061 s->channel[c].prev_block_len = s->subframe_len;
1066 *@brief Decode a single subframe (block).
1067 *@param s codec context
1068 *@return 0 on success, < 0 when decoding failed
1070 static int decode_subframe(WMAProDecodeCtx *s)
1072 int offset = s->samples_per_frame;
1073 int subframe_len = s->samples_per_frame;
1075 int total_samples = s->samples_per_frame * s->avctx->channels;
1076 int transmit_coeffs = 0;
1077 int cur_subwoofer_cutoff;
1079 s->subframe_offset = get_bits_count(&s->gb);
1081 /** reset channel context and find the next block offset and size
1082 == the next block of the channel with the smallest number of
1085 for (i = 0; i < s->avctx->channels; i++) {
1086 s->channel[i].grouped = 0;
1087 if (offset > s->channel[i].decoded_samples) {
1088 offset = s->channel[i].decoded_samples;
1090 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1095 "processing subframe with offset %i len %i\n", offset, subframe_len);
1097 /** get a list of all channels that contain the estimated block */
1098 s->channels_for_cur_subframe = 0;
1099 for (i = 0; i < s->avctx->channels; i++) {
1100 const int cur_subframe = s->channel[i].cur_subframe;
1101 /** subtract already processed samples */
1102 total_samples -= s->channel[i].decoded_samples;
1104 /** and count if there are multiple subframes that match our profile */
1105 if (offset == s->channel[i].decoded_samples &&
1106 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1107 total_samples -= s->channel[i].subframe_len[cur_subframe];
1108 s->channel[i].decoded_samples +=
1109 s->channel[i].subframe_len[cur_subframe];
1110 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1111 ++s->channels_for_cur_subframe;
1115 /** check if the frame will be complete after processing the
1118 s->parsed_all_subframes = 1;
1121 av_dlog(s->avctx, "subframe is part of %i channels\n",
1122 s->channels_for_cur_subframe);
1124 /** calculate number of scale factor bands and their offsets */
1125 s->table_idx = av_log2(s->samples_per_frame/subframe_len);
1126 s->num_bands = s->num_sfb[s->table_idx];
1127 s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
1128 cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
1130 /** configure the decoder for the current subframe */
1131 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1132 int c = s->channel_indexes_for_cur_subframe[i];
1134 s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
1138 s->subframe_len = subframe_len;
1139 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1141 /** skip extended header if any */
1142 if (get_bits1(&s->gb)) {
1144 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1145 int len = get_bits(&s->gb, 4);
1146 num_fill_bits = (len ? get_bits(&s->gb, len) : 0) + 1;
1149 if (num_fill_bits >= 0) {
1150 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1151 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1152 return AVERROR_INVALIDDATA;
1155 skip_bits_long(&s->gb, num_fill_bits);
1159 /** no idea for what the following bit is used */
1160 if (get_bits1(&s->gb)) {
1161 avpriv_request_sample(s->avctx, "Reserved bit");
1162 return AVERROR_PATCHWELCOME;
1166 if (decode_channel_transform(s) < 0)
1167 return AVERROR_INVALIDDATA;
1170 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1171 int c = s->channel_indexes_for_cur_subframe[i];
1172 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1173 transmit_coeffs = 1;
1176 av_assert0(s->subframe_len <= WMAPRO_BLOCK_MAX_SIZE);
1177 if (transmit_coeffs) {
1179 int quant_step = 90 * s->bits_per_sample >> 4;
1181 /** decode number of vector coded coefficients */
1182 if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
1183 int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
1184 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1185 int c = s->channel_indexes_for_cur_subframe[i];
1186 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
1187 if (num_vec_coeffs > s->subframe_len) {
1188 av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
1189 return AVERROR_INVALIDDATA;
1191 s->channel[c].num_vec_coeffs = num_vec_coeffs;
1194 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1195 int c = s->channel_indexes_for_cur_subframe[i];
1196 s->channel[c].num_vec_coeffs = s->subframe_len;
1199 /** decode quantization step */
1200 step = get_sbits(&s->gb, 6);
1202 if (step == -32 || step == 31) {
1203 const int sign = (step == 31) - 1;
1205 while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
1206 (step = get_bits(&s->gb, 5)) == 31) {
1209 quant_step += ((quant + step) ^ sign) - sign;
1211 if (quant_step < 0) {
1212 av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
1215 /** decode quantization step modifiers for every channel */
1217 if (s->channels_for_cur_subframe == 1) {
1218 s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
1220 int modifier_len = get_bits(&s->gb, 3);
1221 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1222 int c = s->channel_indexes_for_cur_subframe[i];
1223 s->channel[c].quant_step = quant_step;
1224 if (get_bits1(&s->gb)) {
1226 s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
1228 ++s->channel[c].quant_step;
1233 /** decode scale factors */
1234 if (decode_scale_factors(s) < 0)
1235 return AVERROR_INVALIDDATA;
1238 av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
1239 get_bits_count(&s->gb) - s->subframe_offset);
1241 /** parse coefficients */
1242 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1243 int c = s->channel_indexes_for_cur_subframe[i];
1244 if (s->channel[c].transmit_coefs &&
1245 get_bits_count(&s->gb) < s->num_saved_bits) {
1246 decode_coeffs(s, c);
1248 memset(s->channel[c].coeffs, 0,
1249 sizeof(*s->channel[c].coeffs) * subframe_len);
1252 av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
1253 get_bits_count(&s->gb) - s->subframe_offset);
1255 if (transmit_coeffs) {
1256 FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
1257 /** reconstruct the per channel data */
1258 inverse_channel_transform(s);
1259 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1260 int c = s->channel_indexes_for_cur_subframe[i];
1261 const int* sf = s->channel[c].scale_factors;
1264 if (c == s->lfe_channel)
1265 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
1266 (subframe_len - cur_subwoofer_cutoff));
1268 /** inverse quantization and rescaling */
1269 for (b = 0; b < s->num_bands; b++) {
1270 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
1271 const int exp = s->channel[c].quant_step -
1272 (s->channel[c].max_scale_factor - *sf++) *
1273 s->channel[c].scale_factor_step;
1274 const float quant = pow(10.0, exp / 20.0);
1275 int start = s->cur_sfb_offsets[b];
1276 s->fdsp.vector_fmul_scalar(s->tmp + start,
1277 s->channel[c].coeffs + start,
1278 quant, end - start);
1281 /** apply imdct (imdct_half == DCTIV with reverse) */
1282 mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
1286 /** window and overlapp-add */
1289 /** handled one subframe */
1290 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1291 int c = s->channel_indexes_for_cur_subframe[i];
1292 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1293 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1294 return AVERROR_INVALIDDATA;
1296 ++s->channel[c].cur_subframe;
1303 *@brief Decode one WMA frame.
1304 *@param s codec context
1305 *@return 0 if the trailer bit indicates that this is the last frame,
1306 * 1 if there are additional frames
1308 static int decode_frame(WMAProDecodeCtx *s, AVFrame *frame, int *got_frame_ptr)
1310 AVCodecContext *avctx = s->avctx;
1311 GetBitContext* gb = &s->gb;
1312 int more_frames = 0;
1316 /** get frame length */
1318 len = get_bits(gb, s->log2_frame_size);
1320 av_dlog(s->avctx, "decoding frame with length %x\n", len);
1322 /** decode tile information */
1323 if (decode_tilehdr(s)) {
1328 /** read postproc transform */
1329 if (s->avctx->channels > 1 && get_bits1(gb)) {
1330 if (get_bits1(gb)) {
1331 for (i = 0; i < avctx->channels * avctx->channels; i++)
1336 /** read drc info */
1337 if (s->dynamic_range_compression) {
1338 s->drc_gain = get_bits(gb, 8);
1339 av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
1342 /** no idea what these are for, might be the number of samples
1343 that need to be skipped at the beginning or end of a stream */
1344 if (get_bits1(gb)) {
1347 /** usually true for the first frame */
1348 if (get_bits1(gb)) {
1349 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1350 av_dlog(s->avctx, "start skip: %i\n", skip);
1353 /** sometimes true for the last frame */
1354 if (get_bits1(gb)) {
1355 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1356 av_dlog(s->avctx, "end skip: %i\n", skip);
1361 av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
1362 get_bits_count(gb) - s->frame_offset);
1364 /** reset subframe states */
1365 s->parsed_all_subframes = 0;
1366 for (i = 0; i < avctx->channels; i++) {
1367 s->channel[i].decoded_samples = 0;
1368 s->channel[i].cur_subframe = 0;
1369 s->channel[i].reuse_sf = 0;
1372 /** decode all subframes */
1373 while (!s->parsed_all_subframes) {
1374 if (decode_subframe(s) < 0) {
1380 /* get output buffer */
1381 frame->nb_samples = s->samples_per_frame;
1382 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
1387 /** copy samples to the output buffer */
1388 for (i = 0; i < avctx->channels; i++)
1389 memcpy(frame->extended_data[i], s->channel[i].out,
1390 s->samples_per_frame * sizeof(*s->channel[i].out));
1392 for (i = 0; i < avctx->channels; i++) {
1393 /** reuse second half of the IMDCT output for the next frame */
1394 memcpy(&s->channel[i].out[0],
1395 &s->channel[i].out[s->samples_per_frame],
1396 s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
1399 if (s->skip_frame) {
1402 av_frame_unref(frame);
1407 if (s->len_prefix) {
1408 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1409 /** FIXME: not sure if this is always an error */
1410 av_log(s->avctx, AV_LOG_ERROR,
1411 "frame[%i] would have to skip %i bits\n", s->frame_num,
1412 len - (get_bits_count(gb) - s->frame_offset) - 1);
1417 /** skip the rest of the frame data */
1418 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1420 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1424 /** decode trailer bit */
1425 more_frames = get_bits1(gb);
1432 *@brief Calculate remaining input buffer length.
1433 *@param s codec context
1434 *@param gb bitstream reader context
1435 *@return remaining size in bits
1437 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1439 return s->buf_bit_size - get_bits_count(gb);
1443 *@brief Fill the bit reservoir with a (partial) frame.
1444 *@param s codec context
1445 *@param gb bitstream reader context
1446 *@param len length of the partial frame
1447 *@param append decides whether to reset the buffer or not
1449 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1454 /** when the frame data does not need to be concatenated, the input buffer
1455 is reset and additional bits from the previous frame are copied
1456 and skipped later so that a fast byte copy is possible */
1459 s->frame_offset = get_bits_count(gb) & 7;
1460 s->num_saved_bits = s->frame_offset;
1461 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1464 buflen = (put_bits_count(&s->pb) + len + 8) >> 3;
1466 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1467 avpriv_request_sample(s->avctx, "Too small input buffer");
1472 s->num_saved_bits += len;
1474 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1477 int align = 8 - (get_bits_count(gb) & 7);
1478 align = FFMIN(align, len);
1479 put_bits(&s->pb, align, get_bits(gb, align));
1481 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1483 skip_bits_long(gb, len);
1486 PutBitContext tmp = s->pb;
1487 flush_put_bits(&tmp);
1490 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1491 skip_bits(&s->gb, s->frame_offset);
1495 *@brief Decode a single WMA packet.
1496 *@param avctx codec context
1497 *@param data the output buffer
1498 *@param avpkt input packet
1499 *@return number of bytes that were read from the input buffer
1501 static int decode_packet(AVCodecContext *avctx, void *data,
1502 int *got_frame_ptr, AVPacket* avpkt)
1504 WMAProDecodeCtx *s = avctx->priv_data;
1505 GetBitContext* gb = &s->pgb;
1506 const uint8_t* buf = avpkt->data;
1507 int buf_size = avpkt->size;
1508 int num_bits_prev_frame;
1509 int packet_sequence_number;
1513 if (s->packet_done || s->packet_loss) {
1516 /** sanity check for the buffer length */
1517 if (buf_size < avctx->block_align) {
1518 av_log(avctx, AV_LOG_ERROR, "Input packet too small (%d < %d)\n",
1519 buf_size, avctx->block_align);
1520 return AVERROR_INVALIDDATA;
1523 s->next_packet_start = buf_size - avctx->block_align;
1524 buf_size = avctx->block_align;
1525 s->buf_bit_size = buf_size << 3;
1527 /** parse packet header */
1528 init_get_bits(gb, buf, s->buf_bit_size);
1529 packet_sequence_number = get_bits(gb, 4);
1532 /** get number of bits that need to be added to the previous frame */
1533 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1534 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1535 num_bits_prev_frame);
1537 /** check for packet loss */
1538 if (!s->packet_loss &&
1539 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1541 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
1542 s->packet_sequence_number, packet_sequence_number);
1544 s->packet_sequence_number = packet_sequence_number;
1546 if (num_bits_prev_frame > 0) {
1547 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1548 if (num_bits_prev_frame >= remaining_packet_bits) {
1549 num_bits_prev_frame = remaining_packet_bits;
1553 /** append the previous frame data to the remaining data from the
1554 previous packet to create a full frame */
1555 save_bits(s, gb, num_bits_prev_frame, 1);
1556 av_dlog(avctx, "accumulated %x bits of frame data\n",
1557 s->num_saved_bits - s->frame_offset);
1559 /** decode the cross packet frame if it is valid */
1560 if (!s->packet_loss)
1561 decode_frame(s, data, got_frame_ptr);
1562 } else if (s->num_saved_bits - s->frame_offset) {
1563 av_dlog(avctx, "ignoring %x previously saved bits\n",
1564 s->num_saved_bits - s->frame_offset);
1567 if (s->packet_loss) {
1568 /** reset number of saved bits so that the decoder
1569 does not start to decode incomplete frames in the
1570 s->len_prefix == 0 case */
1571 s->num_saved_bits = 0;
1577 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1578 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1579 skip_bits(gb, s->packet_offset);
1580 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1581 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1582 frame_size <= remaining_bits(s, gb)) {
1583 save_bits(s, gb, frame_size, 0);
1584 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1585 } else if (!s->len_prefix
1586 && s->num_saved_bits > get_bits_count(&s->gb)) {
1587 /** when the frames do not have a length prefix, we don't know
1588 the compressed length of the individual frames
1589 however, we know what part of a new packet belongs to the
1591 therefore we save the incoming packet first, then we append
1592 the "previous frame" data from the next packet so that
1593 we get a buffer that only contains full frames */
1594 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1599 if (s->packet_done && !s->packet_loss &&
1600 remaining_bits(s, gb) > 0) {
1601 /** save the rest of the data so that it can be decoded
1602 with the next packet */
1603 save_bits(s, gb, remaining_bits(s, gb), 0);
1606 s->packet_offset = get_bits_count(gb) & 7;
1608 return AVERROR_INVALIDDATA;
1610 return get_bits_count(gb) >> 3;
1614 *@brief Clear decoder buffers (for seeking).
1615 *@param avctx codec context
1617 static void flush(AVCodecContext *avctx)
1619 WMAProDecodeCtx *s = avctx->priv_data;
1621 /** reset output buffer as a part of it is used during the windowing of a
1623 for (i = 0; i < avctx->channels; i++)
1624 memset(s->channel[i].out, 0, s->samples_per_frame *
1625 sizeof(*s->channel[i].out));
1631 *@brief wmapro decoder
1633 AVCodec ff_wmapro_decoder = {
1635 .type = AVMEDIA_TYPE_AUDIO,
1636 .id = AV_CODEC_ID_WMAPRO,
1637 .priv_data_size = sizeof(WMAProDecodeCtx),
1638 .init = decode_init,
1639 .close = decode_end,
1640 .decode = decode_packet,
1641 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1643 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1644 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1645 AV_SAMPLE_FMT_NONE },