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"
100 #include "wma_common.h"
102 /** current decoder limitations */
103 #define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels
104 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
105 #define MAX_BANDS 29 ///< max number of scale factor bands
106 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
108 #define WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
109 #define WMAPRO_BLOCK_MAX_BITS 13 ///< log2 of max block size
110 #define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size
111 #define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
115 #define SCALEVLCBITS 8
116 #define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
117 #define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
118 #define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
119 #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
120 #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
122 static VLC sf_vlc; ///< scale factor DPCM vlc
123 static VLC sf_rl_vlc; ///< scale factor run length vlc
124 static VLC vec4_vlc; ///< 4 coefficients per symbol
125 static VLC vec2_vlc; ///< 2 coefficients per symbol
126 static VLC vec1_vlc; ///< 1 coefficient per symbol
127 static VLC coef_vlc[2]; ///< coefficient run length vlc codes
128 static float sin64[33]; ///< sinus table for decorrelation
131 * @brief frame specific decoder context for a single channel
134 int16_t prev_block_len; ///< length of the previous block
135 uint8_t transmit_coefs;
136 uint8_t num_subframes;
137 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
138 uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
139 uint8_t cur_subframe; ///< current subframe number
140 uint16_t decoded_samples; ///< number of already processed samples
141 uint8_t grouped; ///< channel is part of a group
142 int quant_step; ///< quantization step for the current subframe
143 int8_t reuse_sf; ///< share scale factors between subframes
144 int8_t scale_factor_step; ///< scaling step for the current subframe
145 int max_scale_factor; ///< maximum scale factor for the current subframe
146 int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
147 int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
148 int* scale_factors; ///< pointer to the scale factor values used for decoding
149 uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
150 float* coeffs; ///< pointer to the subframe decode buffer
151 uint16_t num_vec_coeffs; ///< number of vector coded coefficients
152 DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer
156 * @brief channel group for channel transformations
159 uint8_t num_channels; ///< number of channels in the group
160 int8_t transform; ///< transform on / off
161 int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
162 float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
163 float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients
167 * @brief main decoder context
169 typedef struct WMAProDecodeCtx {
170 /* generic decoder variables */
171 AVCodecContext* avctx; ///< codec context for av_log
172 AVFrame frame; ///< AVFrame for decoded output
173 AVFloatDSPContext fdsp;
174 uint8_t frame_data[MAX_FRAMESIZE +
175 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
176 PutBitContext pb; ///< context for filling the frame_data buffer
177 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
178 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
179 float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
181 /* frame size dependent frame information (set during initialization) */
182 uint32_t decode_flags; ///< used compression features
183 uint8_t len_prefix; ///< frame is prefixed with its length
184 uint8_t dynamic_range_compression; ///< frame contains DRC data
185 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
186 uint16_t samples_per_frame; ///< number of samples to output
187 uint16_t log2_frame_size;
188 int8_t lfe_channel; ///< lfe channel index
189 uint8_t max_num_subframes;
190 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
191 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
192 uint16_t min_samples_per_subframe;
193 int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
194 int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
195 int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
196 int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
198 /* packet decode state */
199 GetBitContext pgb; ///< bitstream reader context for the packet
200 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
201 uint8_t packet_offset; ///< frame offset in the packet
202 uint8_t packet_sequence_number; ///< current packet number
203 int num_saved_bits; ///< saved number of bits
204 int frame_offset; ///< frame offset in the bit reservoir
205 int subframe_offset; ///< subframe offset in the bit reservoir
206 uint8_t packet_loss; ///< set in case of bitstream error
207 uint8_t packet_done; ///< set when a packet is fully decoded
209 /* frame decode state */
210 uint32_t frame_num; ///< current frame number (not used for decoding)
211 GetBitContext gb; ///< bitstream reader context
212 int buf_bit_size; ///< buffer size in bits
213 uint8_t drc_gain; ///< gain for the DRC tool
214 int8_t skip_frame; ///< skip output step
215 int8_t parsed_all_subframes; ///< all subframes decoded?
217 /* subframe/block decode state */
218 int16_t subframe_len; ///< current subframe length
219 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
220 int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
221 int8_t num_bands; ///< number of scale factor bands
222 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
223 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
224 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
225 int8_t esc_len; ///< length of escaped coefficients
227 uint8_t num_chgroups; ///< number of channel groups
228 WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
230 WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
235 *@brief helper function to print the most important members of the context
238 static av_cold void dump_context(WMAProDecodeCtx *s)
240 #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
241 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
243 PRINT("ed sample bit depth", s->bits_per_sample);
244 PRINT_HEX("ed decode flags", s->decode_flags);
245 PRINT("samples per frame", s->samples_per_frame);
246 PRINT("log2 frame size", s->log2_frame_size);
247 PRINT("max num subframes", s->max_num_subframes);
248 PRINT("len prefix", s->len_prefix);
249 PRINT("num channels", s->avctx->channels);
253 *@brief Uninitialize the decoder and free all resources.
254 *@param avctx codec context
255 *@return 0 on success, < 0 otherwise
257 static av_cold int decode_end(AVCodecContext *avctx)
259 WMAProDecodeCtx *s = avctx->priv_data;
262 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
263 ff_mdct_end(&s->mdct_ctx[i]);
269 *@brief Initialize the decoder.
270 *@param avctx codec context
271 *@return 0 on success, -1 otherwise
273 static av_cold int decode_init(AVCodecContext *avctx)
275 WMAProDecodeCtx *s = avctx->priv_data;
276 uint8_t *edata_ptr = avctx->extradata;
277 unsigned int channel_mask;
279 int log2_max_num_subframes;
280 int num_possible_block_sizes;
283 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
285 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
287 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
289 if (avctx->extradata_size >= 18) {
290 s->decode_flags = AV_RL16(edata_ptr+14);
291 channel_mask = AV_RL32(edata_ptr+2);
292 s->bits_per_sample = AV_RL16(edata_ptr);
293 /** dump the extradata */
294 for (i = 0; i < avctx->extradata_size; i++)
295 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
296 av_dlog(avctx, "\n");
299 av_log_ask_for_sample(avctx, "Unknown extradata size\n");
300 return AVERROR_PATCHWELCOME;
304 s->log2_frame_size = av_log2(avctx->block_align) + 4;
307 s->skip_frame = 1; /* skip first frame */
309 s->len_prefix = (s->decode_flags & 0x40);
312 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
313 if (bits > WMAPRO_BLOCK_MAX_BITS) {
314 av_log_missing_feature(avctx, "14-bits block sizes", 1);
315 return AVERROR_PATCHWELCOME;
317 s->samples_per_frame = 1 << bits;
320 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
321 s->max_num_subframes = 1 << log2_max_num_subframes;
322 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
323 s->max_subframe_len_bit = 1;
324 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
326 num_possible_block_sizes = log2_max_num_subframes + 1;
327 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
328 s->dynamic_range_compression = (s->decode_flags & 0x80);
330 if (s->max_num_subframes > MAX_SUBFRAMES) {
331 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
332 s->max_num_subframes);
333 return AVERROR_INVALIDDATA;
336 if (s->min_samples_per_subframe < (1<<WMAPRO_BLOCK_MIN_BITS)) {
337 av_log(avctx, AV_LOG_ERROR, "min_samples_per_subframe of %d too small\n",
338 s->min_samples_per_subframe);
339 return AVERROR_INVALIDDATA;
342 if (s->avctx->sample_rate <= 0) {
343 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
344 return AVERROR_INVALIDDATA;
347 if (avctx->channels < 0) {
348 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
350 return AVERROR_INVALIDDATA;
351 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
352 av_log_ask_for_sample(avctx, "unsupported number of channels\n");
353 return AVERROR_PATCHWELCOME;
356 /** init previous block len */
357 for (i = 0; i < avctx->channels; i++)
358 s->channel[i].prev_block_len = s->samples_per_frame;
360 /** extract lfe channel position */
363 if (channel_mask & 8) {
365 for (mask = 1; mask < 16; mask <<= 1) {
366 if (channel_mask & mask)
371 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
372 scale_huffbits, 1, 1,
373 scale_huffcodes, 2, 2, 616);
375 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
376 scale_rl_huffbits, 1, 1,
377 scale_rl_huffcodes, 4, 4, 1406);
379 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
380 coef0_huffbits, 1, 1,
381 coef0_huffcodes, 4, 4, 2108);
383 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
384 coef1_huffbits, 1, 1,
385 coef1_huffcodes, 4, 4, 3912);
387 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
389 vec4_huffcodes, 2, 2, 604);
391 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
393 vec2_huffcodes, 2, 2, 562);
395 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
397 vec1_huffcodes, 2, 2, 562);
399 /** calculate number of scale factor bands and their offsets
400 for every possible block size */
401 for (i = 0; i < num_possible_block_sizes; i++) {
402 int subframe_len = s->samples_per_frame >> i;
406 s->sfb_offsets[i][0] = 0;
408 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
409 int offset = (subframe_len * 2 * critical_freq[x])
410 / s->avctx->sample_rate + 2;
412 if (offset > s->sfb_offsets[i][band - 1])
413 s->sfb_offsets[i][band++] = offset;
415 s->sfb_offsets[i][band - 1] = subframe_len;
416 s->num_sfb[i] = band - 1;
417 if (s->num_sfb[i] <= 0) {
418 av_log(avctx, AV_LOG_ERROR, "num_sfb invalid\n");
419 return AVERROR_INVALIDDATA;
424 /** Scale factors can be shared between blocks of different size
425 as every block has a different scale factor band layout.
426 The matrix sf_offsets is needed to find the correct scale factor.
429 for (i = 0; i < num_possible_block_sizes; i++) {
431 for (b = 0; b < s->num_sfb[i]; b++) {
433 int offset = ((s->sfb_offsets[i][b]
434 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
435 for (x = 0; x < num_possible_block_sizes; x++) {
437 while (s->sfb_offsets[x][v + 1] << x < offset)
439 s->sf_offsets[i][x][b] = v;
444 /** init MDCT, FIXME: only init needed sizes */
445 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
446 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
447 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
448 / (1 << (s->bits_per_sample - 1)));
450 /** init MDCT windows: simple sinus window */
451 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
452 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
453 ff_init_ff_sine_windows(win_idx);
454 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
457 /** calculate subwoofer cutoff values */
458 for (i = 0; i < num_possible_block_sizes; i++) {
459 int block_size = s->samples_per_frame >> i;
460 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
461 / s->avctx->sample_rate;
462 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
465 /** calculate sine values for the decorrelation matrix */
466 for (i = 0; i < 33; i++)
467 sin64[i] = sin(i*M_PI / 64.0);
469 if (avctx->debug & FF_DEBUG_BITSTREAM)
472 avctx->channel_layout = channel_mask;
474 avcodec_get_frame_defaults(&s->frame);
475 avctx->coded_frame = &s->frame;
481 *@brief Decode the subframe length.
483 *@param offset sample offset in the frame
484 *@return decoded subframe length on success, < 0 in case of an error
486 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
488 int frame_len_shift = 0;
491 /** no need to read from the bitstream when only one length is possible */
492 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
493 return s->min_samples_per_subframe;
495 /** 1 bit indicates if the subframe is of maximum length */
496 if (s->max_subframe_len_bit) {
497 if (get_bits1(&s->gb))
498 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
500 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
502 subframe_len = s->samples_per_frame >> frame_len_shift;
504 /** sanity check the length */
505 if (subframe_len < s->min_samples_per_subframe ||
506 subframe_len > s->samples_per_frame) {
507 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
509 return AVERROR_INVALIDDATA;
515 *@brief Decode how the data in the frame is split into subframes.
516 * Every WMA frame contains the encoded data for a fixed number of
517 * samples per channel. The data for every channel might be split
518 * into several subframes. This function will reconstruct the list of
519 * subframes for every channel.
521 * If the subframes are not evenly split, the algorithm estimates the
522 * channels with the lowest number of total samples.
523 * Afterwards, for each of these channels a bit is read from the
524 * bitstream that indicates if the channel contains a subframe with the
525 * next subframe size that is going to be read from the bitstream or not.
526 * If a channel contains such a subframe, the subframe size gets added to
527 * the channel's subframe list.
528 * The algorithm repeats these steps until the frame is properly divided
529 * between the individual channels.
532 *@return 0 on success, < 0 in case of an error
534 static int decode_tilehdr(WMAProDecodeCtx *s)
536 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
537 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
538 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
539 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
540 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
543 /* Should never consume more than 3073 bits (256 iterations for the
544 * while loop when always the minimum amount of 128 samples is subtracted
545 * from missing samples in the 8 channel case).
546 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
549 /** reset tiling information */
550 for (c = 0; c < s->avctx->channels; c++)
551 s->channel[c].num_subframes = 0;
553 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
554 fixed_channel_layout = 1;
556 /** loop until the frame data is split between the subframes */
560 /** check which channels contain the subframe */
561 for (c = 0; c < s->avctx->channels; c++) {
562 if (num_samples[c] == min_channel_len) {
563 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
564 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
565 contains_subframe[c] = 1;
567 contains_subframe[c] = get_bits1(&s->gb);
569 contains_subframe[c] = 0;
572 /** get subframe length, subframe_len == 0 is not allowed */
573 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
574 return AVERROR_INVALIDDATA;
576 /** add subframes to the individual channels and find new min_channel_len */
577 min_channel_len += subframe_len;
578 for (c = 0; c < s->avctx->channels; c++) {
579 WMAProChannelCtx* chan = &s->channel[c];
581 if (contains_subframe[c]) {
582 if (chan->num_subframes >= MAX_SUBFRAMES) {
583 av_log(s->avctx, AV_LOG_ERROR,
584 "broken frame: num subframes > 31\n");
585 return AVERROR_INVALIDDATA;
587 chan->subframe_len[chan->num_subframes] = subframe_len;
588 num_samples[c] += subframe_len;
589 ++chan->num_subframes;
590 if (num_samples[c] > s->samples_per_frame) {
591 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
592 "channel len > samples_per_frame\n");
593 return AVERROR_INVALIDDATA;
595 } else if (num_samples[c] <= min_channel_len) {
596 if (num_samples[c] < min_channel_len) {
597 channels_for_cur_subframe = 0;
598 min_channel_len = num_samples[c];
600 ++channels_for_cur_subframe;
603 } while (min_channel_len < s->samples_per_frame);
605 for (c = 0; c < s->avctx->channels; c++) {
608 for (i = 0; i < s->channel[c].num_subframes; i++) {
609 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
610 " len %i\n", s->frame_num, c, i,
611 s->channel[c].subframe_len[i]);
612 s->channel[c].subframe_offset[i] = offset;
613 offset += s->channel[c].subframe_len[i];
621 *@brief Calculate a decorrelation matrix from the bitstream parameters.
622 *@param s codec context
623 *@param chgroup channel group for which the matrix needs to be calculated
625 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
626 WMAProChannelGrp *chgroup)
630 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
631 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
632 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
634 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
635 rotation_offset[i] = get_bits(&s->gb, 6);
637 for (i = 0; i < chgroup->num_channels; i++)
638 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
639 get_bits1(&s->gb) ? 1.0 : -1.0;
641 for (i = 1; i < chgroup->num_channels; i++) {
643 for (x = 0; x < i; x++) {
645 for (y = 0; y < i + 1; y++) {
646 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
647 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
648 int n = rotation_offset[offset + x];
654 cosv = sin64[32 - n];
656 sinv = sin64[64 - n];
657 cosv = -sin64[n - 32];
660 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
661 (v1 * sinv) - (v2 * cosv);
662 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
663 (v1 * cosv) + (v2 * sinv);
671 *@brief Decode channel transformation parameters
672 *@param s codec context
673 *@return 0 in case of success, < 0 in case of bitstream errors
675 static int decode_channel_transform(WMAProDecodeCtx* s)
678 /* should never consume more than 1921 bits for the 8 channel case
679 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
680 * + MAX_CHANNELS + MAX_BANDS + 1)
683 /** in the one channel case channel transforms are pointless */
685 if (s->avctx->channels > 1) {
686 int remaining_channels = s->channels_for_cur_subframe;
688 if (get_bits1(&s->gb)) {
689 av_log_ask_for_sample(s->avctx,
690 "unsupported channel transform bit\n");
691 return AVERROR_PATCHWELCOME;
694 for (s->num_chgroups = 0; remaining_channels &&
695 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
696 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
697 float** channel_data = chgroup->channel_data;
698 chgroup->num_channels = 0;
699 chgroup->transform = 0;
701 /** decode channel mask */
702 if (remaining_channels > 2) {
703 for (i = 0; i < s->channels_for_cur_subframe; i++) {
704 int channel_idx = s->channel_indexes_for_cur_subframe[i];
705 if (!s->channel[channel_idx].grouped
706 && get_bits1(&s->gb)) {
707 ++chgroup->num_channels;
708 s->channel[channel_idx].grouped = 1;
709 *channel_data++ = s->channel[channel_idx].coeffs;
713 chgroup->num_channels = remaining_channels;
714 for (i = 0; i < s->channels_for_cur_subframe; i++) {
715 int channel_idx = s->channel_indexes_for_cur_subframe[i];
716 if (!s->channel[channel_idx].grouped)
717 *channel_data++ = s->channel[channel_idx].coeffs;
718 s->channel[channel_idx].grouped = 1;
722 /** decode transform type */
723 if (chgroup->num_channels == 2) {
724 if (get_bits1(&s->gb)) {
725 if (get_bits1(&s->gb)) {
726 av_log_ask_for_sample(s->avctx,
727 "unsupported channel transform type\n");
730 chgroup->transform = 1;
731 if (s->avctx->channels == 2) {
732 chgroup->decorrelation_matrix[0] = 1.0;
733 chgroup->decorrelation_matrix[1] = -1.0;
734 chgroup->decorrelation_matrix[2] = 1.0;
735 chgroup->decorrelation_matrix[3] = 1.0;
738 chgroup->decorrelation_matrix[0] = 0.70703125;
739 chgroup->decorrelation_matrix[1] = -0.70703125;
740 chgroup->decorrelation_matrix[2] = 0.70703125;
741 chgroup->decorrelation_matrix[3] = 0.70703125;
744 } else if (chgroup->num_channels > 2) {
745 if (get_bits1(&s->gb)) {
746 chgroup->transform = 1;
747 if (get_bits1(&s->gb)) {
748 decode_decorrelation_matrix(s, chgroup);
750 /** FIXME: more than 6 coupled channels not supported */
751 if (chgroup->num_channels > 6) {
752 av_log_ask_for_sample(s->avctx,
753 "coupled channels > 6\n");
755 memcpy(chgroup->decorrelation_matrix,
756 default_decorrelation[chgroup->num_channels],
757 chgroup->num_channels * chgroup->num_channels *
758 sizeof(*chgroup->decorrelation_matrix));
764 /** decode transform on / off */
765 if (chgroup->transform) {
766 if (!get_bits1(&s->gb)) {
768 /** transform can be enabled for individual bands */
769 for (i = 0; i < s->num_bands; i++) {
770 chgroup->transform_band[i] = get_bits1(&s->gb);
773 memset(chgroup->transform_band, 1, s->num_bands);
776 remaining_channels -= chgroup->num_channels;
783 *@brief Extract the coefficients from the bitstream.
784 *@param s codec context
785 *@param c current channel number
786 *@return 0 on success, < 0 in case of bitstream errors
788 static int decode_coeffs(WMAProDecodeCtx *s, int c)
790 /* Integers 0..15 as single-precision floats. The table saves a
791 costly int to float conversion, and storing the values as
792 integers allows fast sign-flipping. */
793 static const uint32_t fval_tab[16] = {
794 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
795 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
796 0x41000000, 0x41100000, 0x41200000, 0x41300000,
797 0x41400000, 0x41500000, 0x41600000, 0x41700000,
801 WMAProChannelCtx* ci = &s->channel[c];
808 av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
810 vlctable = get_bits1(&s->gb);
811 vlc = &coef_vlc[vlctable];
821 /** decode vector coefficients (consumes up to 167 bits per iteration for
822 4 vector coded large values) */
823 while ((s->transmit_num_vec_coeffs || !rl_mode) &&
824 (cur_coeff + 3 < ci->num_vec_coeffs)) {
829 idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
831 if (idx == HUFF_VEC4_SIZE - 1) {
832 for (i = 0; i < 4; i += 2) {
833 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
834 if (idx == HUFF_VEC2_SIZE - 1) {
836 v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
837 if (v0 == HUFF_VEC1_SIZE - 1)
838 v0 += ff_wma_get_large_val(&s->gb);
839 v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
840 if (v1 == HUFF_VEC1_SIZE - 1)
841 v1 += ff_wma_get_large_val(&s->gb);
842 vals[i ] = av_float2int(v0);
843 vals[i+1] = av_float2int(v1);
845 vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
846 vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
850 vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
851 vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
852 vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
853 vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
857 for (i = 0; i < 4; i++) {
859 uint32_t sign = get_bits1(&s->gb) - 1;
860 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
863 ci->coeffs[cur_coeff] = 0;
864 /** switch to run level mode when subframe_len / 128 zeros
865 were found in a row */
866 rl_mode |= (++num_zeros > s->subframe_len >> 8);
872 /** decode run level coded coefficients */
873 if (cur_coeff < s->subframe_len) {
874 memset(&ci->coeffs[cur_coeff], 0,
875 sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
876 if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
877 level, run, 1, ci->coeffs,
878 cur_coeff, s->subframe_len,
879 s->subframe_len, s->esc_len, 0))
880 return AVERROR_INVALIDDATA;
887 *@brief Extract scale factors from the bitstream.
888 *@param s codec context
889 *@return 0 on success, < 0 in case of bitstream errors
891 static int decode_scale_factors(WMAProDecodeCtx* s)
895 /** should never consume more than 5344 bits
896 * MAX_CHANNELS * (1 + MAX_BANDS * 23)
899 for (i = 0; i < s->channels_for_cur_subframe; i++) {
900 int c = s->channel_indexes_for_cur_subframe[i];
903 s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
904 sf_end = s->channel[c].scale_factors + s->num_bands;
906 /** resample scale factors for the new block size
907 * as the scale factors might need to be resampled several times
908 * before some new values are transmitted, a backup of the last
909 * transmitted scale factors is kept in saved_scale_factors
911 if (s->channel[c].reuse_sf) {
912 const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
914 for (b = 0; b < s->num_bands; b++)
915 s->channel[c].scale_factors[b] =
916 s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
919 if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
921 if (!s->channel[c].reuse_sf) {
923 /** decode DPCM coded scale factors */
924 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
925 val = 45 / s->channel[c].scale_factor_step;
926 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
927 val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
932 /** run level decode differences to the resampled factors */
933 for (i = 0; i < s->num_bands; i++) {
939 idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
942 uint32_t code = get_bits(&s->gb, 14);
944 sign = (code & 1) - 1;
945 skip = (code & 0x3f) >> 1;
946 } else if (idx == 1) {
949 skip = scale_rl_run[idx];
950 val = scale_rl_level[idx];
951 sign = get_bits1(&s->gb)-1;
955 if (i >= s->num_bands) {
956 av_log(s->avctx, AV_LOG_ERROR,
957 "invalid scale factor coding\n");
958 return AVERROR_INVALIDDATA;
960 s->channel[c].scale_factors[i] += (val ^ sign) - sign;
964 s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
965 s->channel[c].table_idx = s->table_idx;
966 s->channel[c].reuse_sf = 1;
969 /** calculate new scale factor maximum */
970 s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
971 for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
972 s->channel[c].max_scale_factor =
973 FFMAX(s->channel[c].max_scale_factor, *sf);
981 *@brief Reconstruct the individual channel data.
982 *@param s codec context
984 static void inverse_channel_transform(WMAProDecodeCtx *s)
988 for (i = 0; i < s->num_chgroups; i++) {
989 if (s->chgroup[i].transform) {
990 float data[WMAPRO_MAX_CHANNELS];
991 const int num_channels = s->chgroup[i].num_channels;
992 float** ch_data = s->chgroup[i].channel_data;
993 float** ch_end = ch_data + num_channels;
994 const int8_t* tb = s->chgroup[i].transform_band;
997 /** multichannel decorrelation */
998 for (sfb = s->cur_sfb_offsets;
999 sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
1002 /** multiply values with the decorrelation_matrix */
1003 for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
1004 const float* mat = s->chgroup[i].decorrelation_matrix;
1005 const float* data_end = data + num_channels;
1006 float* data_ptr = data;
1009 for (ch = ch_data; ch < ch_end; ch++)
1010 *data_ptr++ = (*ch)[y];
1012 for (ch = ch_data; ch < ch_end; ch++) {
1015 while (data_ptr < data_end)
1016 sum += *data_ptr++ * *mat++;
1021 } else if (s->avctx->channels == 2) {
1022 int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
1023 s->fdsp.vector_fmul_scalar(ch_data[0] + sfb[0],
1024 ch_data[0] + sfb[0],
1026 s->fdsp.vector_fmul_scalar(ch_data[1] + sfb[0],
1027 ch_data[1] + sfb[0],
1036 *@brief Apply sine window and reconstruct the output buffer.
1037 *@param s codec context
1039 static void wmapro_window(WMAProDecodeCtx *s)
1042 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1043 int c = s->channel_indexes_for_cur_subframe[i];
1045 int winlen = s->channel[c].prev_block_len;
1046 float* start = s->channel[c].coeffs - (winlen >> 1);
1048 if (s->subframe_len < winlen) {
1049 start += (winlen - s->subframe_len) >> 1;
1050 winlen = s->subframe_len;
1053 window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
1057 s->fdsp.vector_fmul_window(start, start, start + winlen,
1060 s->channel[c].prev_block_len = s->subframe_len;
1065 *@brief Decode a single subframe (block).
1066 *@param s codec context
1067 *@return 0 on success, < 0 when decoding failed
1069 static int decode_subframe(WMAProDecodeCtx *s)
1071 int offset = s->samples_per_frame;
1072 int subframe_len = s->samples_per_frame;
1074 int total_samples = s->samples_per_frame * s->avctx->channels;
1075 int transmit_coeffs = 0;
1076 int cur_subwoofer_cutoff;
1078 s->subframe_offset = get_bits_count(&s->gb);
1080 /** reset channel context and find the next block offset and size
1081 == the next block of the channel with the smallest number of
1084 for (i = 0; i < s->avctx->channels; i++) {
1085 s->channel[i].grouped = 0;
1086 if (offset > s->channel[i].decoded_samples) {
1087 offset = s->channel[i].decoded_samples;
1089 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1094 "processing subframe with offset %i len %i\n", offset, subframe_len);
1096 /** get a list of all channels that contain the estimated block */
1097 s->channels_for_cur_subframe = 0;
1098 for (i = 0; i < s->avctx->channels; i++) {
1099 const int cur_subframe = s->channel[i].cur_subframe;
1100 /** subtract already processed samples */
1101 total_samples -= s->channel[i].decoded_samples;
1103 /** and count if there are multiple subframes that match our profile */
1104 if (offset == s->channel[i].decoded_samples &&
1105 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1106 total_samples -= s->channel[i].subframe_len[cur_subframe];
1107 s->channel[i].decoded_samples +=
1108 s->channel[i].subframe_len[cur_subframe];
1109 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1110 ++s->channels_for_cur_subframe;
1114 /** check if the frame will be complete after processing the
1117 s->parsed_all_subframes = 1;
1120 av_dlog(s->avctx, "subframe is part of %i channels\n",
1121 s->channels_for_cur_subframe);
1123 /** calculate number of scale factor bands and their offsets */
1124 s->table_idx = av_log2(s->samples_per_frame/subframe_len);
1125 s->num_bands = s->num_sfb[s->table_idx];
1126 s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
1127 cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
1129 /** configure the decoder for the current subframe */
1130 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1131 int c = s->channel_indexes_for_cur_subframe[i];
1133 s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
1137 s->subframe_len = subframe_len;
1138 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1140 /** skip extended header if any */
1141 if (get_bits1(&s->gb)) {
1143 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1144 int len = get_bits(&s->gb, 4);
1145 num_fill_bits = (len ? get_bits(&s->gb, len) : 0) + 1;
1148 if (num_fill_bits >= 0) {
1149 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1150 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1151 return AVERROR_INVALIDDATA;
1154 skip_bits_long(&s->gb, num_fill_bits);
1158 /** no idea for what the following bit is used */
1159 if (get_bits1(&s->gb)) {
1160 av_log_ask_for_sample(s->avctx, "reserved bit set\n");
1161 return AVERROR_PATCHWELCOME;
1165 if (decode_channel_transform(s) < 0)
1166 return AVERROR_INVALIDDATA;
1169 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1170 int c = s->channel_indexes_for_cur_subframe[i];
1171 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1172 transmit_coeffs = 1;
1175 av_assert0(s->subframe_len <= WMAPRO_BLOCK_MAX_SIZE);
1176 if (transmit_coeffs) {
1178 int quant_step = 90 * s->bits_per_sample >> 4;
1180 /** decode number of vector coded coefficients */
1181 if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
1182 int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
1183 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1184 int c = s->channel_indexes_for_cur_subframe[i];
1185 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
1186 if (num_vec_coeffs > s->subframe_len) {
1187 av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
1188 return AVERROR_INVALIDDATA;
1190 s->channel[c].num_vec_coeffs = num_vec_coeffs;
1193 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1194 int c = s->channel_indexes_for_cur_subframe[i];
1195 s->channel[c].num_vec_coeffs = s->subframe_len;
1198 /** decode quantization step */
1199 step = get_sbits(&s->gb, 6);
1201 if (step == -32 || step == 31) {
1202 const int sign = (step == 31) - 1;
1204 while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
1205 (step = get_bits(&s->gb, 5)) == 31) {
1208 quant_step += ((quant + step) ^ sign) - sign;
1210 if (quant_step < 0) {
1211 av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
1214 /** decode quantization step modifiers for every channel */
1216 if (s->channels_for_cur_subframe == 1) {
1217 s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
1219 int modifier_len = get_bits(&s->gb, 3);
1220 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1221 int c = s->channel_indexes_for_cur_subframe[i];
1222 s->channel[c].quant_step = quant_step;
1223 if (get_bits1(&s->gb)) {
1225 s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
1227 ++s->channel[c].quant_step;
1232 /** decode scale factors */
1233 if (decode_scale_factors(s) < 0)
1234 return AVERROR_INVALIDDATA;
1237 av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
1238 get_bits_count(&s->gb) - s->subframe_offset);
1240 /** parse coefficients */
1241 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1242 int c = s->channel_indexes_for_cur_subframe[i];
1243 if (s->channel[c].transmit_coefs &&
1244 get_bits_count(&s->gb) < s->num_saved_bits) {
1245 decode_coeffs(s, c);
1247 memset(s->channel[c].coeffs, 0,
1248 sizeof(*s->channel[c].coeffs) * subframe_len);
1251 av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
1252 get_bits_count(&s->gb) - s->subframe_offset);
1254 if (transmit_coeffs) {
1255 FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
1256 /** reconstruct the per channel data */
1257 inverse_channel_transform(s);
1258 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1259 int c = s->channel_indexes_for_cur_subframe[i];
1260 const int* sf = s->channel[c].scale_factors;
1263 if (c == s->lfe_channel)
1264 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
1265 (subframe_len - cur_subwoofer_cutoff));
1267 /** inverse quantization and rescaling */
1268 for (b = 0; b < s->num_bands; b++) {
1269 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
1270 const int exp = s->channel[c].quant_step -
1271 (s->channel[c].max_scale_factor - *sf++) *
1272 s->channel[c].scale_factor_step;
1273 const float quant = pow(10.0, exp / 20.0);
1274 int start = s->cur_sfb_offsets[b];
1275 s->fdsp.vector_fmul_scalar(s->tmp + start,
1276 s->channel[c].coeffs + start,
1277 quant, end - start);
1280 /** apply imdct (imdct_half == DCTIV with reverse) */
1281 mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
1285 /** window and overlapp-add */
1288 /** handled one subframe */
1289 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1290 int c = s->channel_indexes_for_cur_subframe[i];
1291 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1292 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1293 return AVERROR_INVALIDDATA;
1295 ++s->channel[c].cur_subframe;
1302 *@brief Decode one WMA frame.
1303 *@param s codec context
1304 *@return 0 if the trailer bit indicates that this is the last frame,
1305 * 1 if there are additional frames
1307 static int decode_frame(WMAProDecodeCtx *s, int *got_frame_ptr)
1309 AVCodecContext *avctx = s->avctx;
1310 GetBitContext* gb = &s->gb;
1311 int more_frames = 0;
1315 /** get frame length */
1317 len = get_bits(gb, s->log2_frame_size);
1319 av_dlog(s->avctx, "decoding frame with length %x\n", len);
1321 /** decode tile information */
1322 if (decode_tilehdr(s)) {
1327 /** read postproc transform */
1328 if (s->avctx->channels > 1 && get_bits1(gb)) {
1329 if (get_bits1(gb)) {
1330 for (i = 0; i < avctx->channels * avctx->channels; i++)
1335 /** read drc info */
1336 if (s->dynamic_range_compression) {
1337 s->drc_gain = get_bits(gb, 8);
1338 av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
1341 /** no idea what these are for, might be the number of samples
1342 that need to be skipped at the beginning or end of a stream */
1343 if (get_bits1(gb)) {
1346 /** usually true for the first frame */
1347 if (get_bits1(gb)) {
1348 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1349 av_dlog(s->avctx, "start skip: %i\n", skip);
1352 /** sometimes true for the last frame */
1353 if (get_bits1(gb)) {
1354 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1355 av_dlog(s->avctx, "end skip: %i\n", skip);
1360 av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
1361 get_bits_count(gb) - s->frame_offset);
1363 /** reset subframe states */
1364 s->parsed_all_subframes = 0;
1365 for (i = 0; i < avctx->channels; i++) {
1366 s->channel[i].decoded_samples = 0;
1367 s->channel[i].cur_subframe = 0;
1368 s->channel[i].reuse_sf = 0;
1371 /** decode all subframes */
1372 while (!s->parsed_all_subframes) {
1373 if (decode_subframe(s) < 0) {
1379 /* get output buffer */
1380 s->frame.nb_samples = s->samples_per_frame;
1381 if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
1382 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1387 /** copy samples to the output buffer */
1388 for (i = 0; i < avctx->channels; i++)
1389 memcpy(s->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) {
1406 if (s->len_prefix) {
1407 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1408 /** FIXME: not sure if this is always an error */
1409 av_log(s->avctx, AV_LOG_ERROR,
1410 "frame[%i] would have to skip %i bits\n", s->frame_num,
1411 len - (get_bits_count(gb) - s->frame_offset) - 1);
1416 /** skip the rest of the frame data */
1417 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1419 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1423 /** decode trailer bit */
1424 more_frames = get_bits1(gb);
1431 *@brief Calculate remaining input buffer length.
1432 *@param s codec context
1433 *@param gb bitstream reader context
1434 *@return remaining size in bits
1436 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1438 return s->buf_bit_size - get_bits_count(gb);
1442 *@brief Fill the bit reservoir with a (partial) frame.
1443 *@param s codec context
1444 *@param gb bitstream reader context
1445 *@param len length of the partial frame
1446 *@param append decides whether to reset the buffer or not
1448 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1453 /** when the frame data does not need to be concatenated, the input buffer
1454 is reset and additional bits from the previous frame are copied
1455 and skipped later so that a fast byte copy is possible */
1458 s->frame_offset = get_bits_count(gb) & 7;
1459 s->num_saved_bits = s->frame_offset;
1460 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1463 buflen = (put_bits_count(&s->pb) + len + 8) >> 3;
1465 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1466 av_log_ask_for_sample(s->avctx, "input buffer too small\n");
1471 s->num_saved_bits += len;
1473 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1476 int align = 8 - (get_bits_count(gb) & 7);
1477 align = FFMIN(align, len);
1478 put_bits(&s->pb, align, get_bits(gb, align));
1480 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1482 skip_bits_long(gb, len);
1485 PutBitContext tmp = s->pb;
1486 flush_put_bits(&tmp);
1489 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1490 skip_bits(&s->gb, s->frame_offset);
1494 *@brief Decode a single WMA packet.
1495 *@param avctx codec context
1496 *@param data the output buffer
1497 *@param avpkt input packet
1498 *@return number of bytes that were read from the input buffer
1500 static int decode_packet(AVCodecContext *avctx, void *data,
1501 int *got_frame_ptr, AVPacket* avpkt)
1503 WMAProDecodeCtx *s = avctx->priv_data;
1504 GetBitContext* gb = &s->pgb;
1505 const uint8_t* buf = avpkt->data;
1506 int buf_size = avpkt->size;
1507 int num_bits_prev_frame;
1508 int packet_sequence_number;
1512 if (s->packet_done || s->packet_loss) {
1515 /** sanity check for the buffer length */
1516 if (buf_size < avctx->block_align)
1519 s->next_packet_start = buf_size - avctx->block_align;
1520 buf_size = avctx->block_align;
1521 s->buf_bit_size = buf_size << 3;
1523 /** parse packet header */
1524 init_get_bits(gb, buf, s->buf_bit_size);
1525 packet_sequence_number = get_bits(gb, 4);
1528 /** get number of bits that need to be added to the previous frame */
1529 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1530 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1531 num_bits_prev_frame);
1533 /** check for packet loss */
1534 if (!s->packet_loss &&
1535 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1537 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
1538 s->packet_sequence_number, packet_sequence_number);
1540 s->packet_sequence_number = packet_sequence_number;
1542 if (num_bits_prev_frame > 0) {
1543 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1544 if (num_bits_prev_frame >= remaining_packet_bits) {
1545 num_bits_prev_frame = remaining_packet_bits;
1549 /** append the previous frame data to the remaining data from the
1550 previous packet to create a full frame */
1551 save_bits(s, gb, num_bits_prev_frame, 1);
1552 av_dlog(avctx, "accumulated %x bits of frame data\n",
1553 s->num_saved_bits - s->frame_offset);
1555 /** decode the cross packet frame if it is valid */
1556 if (!s->packet_loss)
1557 decode_frame(s, got_frame_ptr);
1558 } else if (s->num_saved_bits - s->frame_offset) {
1559 av_dlog(avctx, "ignoring %x previously saved bits\n",
1560 s->num_saved_bits - s->frame_offset);
1563 if (s->packet_loss) {
1564 /** reset number of saved bits so that the decoder
1565 does not start to decode incomplete frames in the
1566 s->len_prefix == 0 case */
1567 s->num_saved_bits = 0;
1573 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1574 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1575 skip_bits(gb, s->packet_offset);
1576 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1577 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1578 frame_size <= remaining_bits(s, gb)) {
1579 save_bits(s, gb, frame_size, 0);
1580 s->packet_done = !decode_frame(s, got_frame_ptr);
1581 } else if (!s->len_prefix
1582 && s->num_saved_bits > get_bits_count(&s->gb)) {
1583 /** when the frames do not have a length prefix, we don't know
1584 the compressed length of the individual frames
1585 however, we know what part of a new packet belongs to the
1587 therefore we save the incoming packet first, then we append
1588 the "previous frame" data from the next packet so that
1589 we get a buffer that only contains full frames */
1590 s->packet_done = !decode_frame(s, got_frame_ptr);
1595 if (s->packet_done && !s->packet_loss &&
1596 remaining_bits(s, gb) > 0) {
1597 /** save the rest of the data so that it can be decoded
1598 with the next packet */
1599 save_bits(s, gb, remaining_bits(s, gb), 0);
1602 s->packet_offset = get_bits_count(gb) & 7;
1604 return AVERROR_INVALIDDATA;
1607 *(AVFrame *)data = s->frame;
1609 return get_bits_count(gb) >> 3;
1613 *@brief Clear decoder buffers (for seeking).
1614 *@param avctx codec context
1616 static void flush(AVCodecContext *avctx)
1618 WMAProDecodeCtx *s = avctx->priv_data;
1620 /** reset output buffer as a part of it is used during the windowing of a
1622 for (i = 0; i < avctx->channels; i++)
1623 memset(s->channel[i].out, 0, s->samples_per_frame *
1624 sizeof(*s->channel[i].out));
1630 *@brief wmapro decoder
1632 AVCodec ff_wmapro_decoder = {
1634 .type = AVMEDIA_TYPE_AUDIO,
1635 .id = AV_CODEC_ID_WMAPRO,
1636 .priv_data_size = sizeof(WMAProDecodeCtx),
1637 .init = decode_init,
1638 .close = decode_end,
1639 .decode = decode_packet,
1640 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1642 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1643 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1644 AV_SAMPLE_FMT_NONE },