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 DSPContext dsp; ///< accelerated DSP functions
174 AVFloatDSPContext fdsp;
175 uint8_t frame_data[MAX_FRAMESIZE +
176 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
177 PutBitContext pb; ///< context for filling the frame_data buffer
178 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
179 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
180 float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
182 /* frame size dependent frame information (set during initialization) */
183 uint32_t decode_flags; ///< used compression features
184 uint8_t len_prefix; ///< frame is prefixed with its length
185 uint8_t dynamic_range_compression; ///< frame contains DRC data
186 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
187 uint16_t samples_per_frame; ///< number of samples to output
188 uint16_t log2_frame_size;
189 int8_t lfe_channel; ///< lfe channel index
190 uint8_t max_num_subframes;
191 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
192 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
193 uint16_t min_samples_per_subframe;
194 int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
195 int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
196 int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
197 int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
199 /* packet decode state */
200 GetBitContext pgb; ///< bitstream reader context for the packet
201 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
202 uint8_t packet_offset; ///< frame offset in the packet
203 uint8_t packet_sequence_number; ///< current packet number
204 int num_saved_bits; ///< saved number of bits
205 int frame_offset; ///< frame offset in the bit reservoir
206 int subframe_offset; ///< subframe offset in the bit reservoir
207 uint8_t packet_loss; ///< set in case of bitstream error
208 uint8_t packet_done; ///< set when a packet is fully decoded
210 /* frame decode state */
211 uint32_t frame_num; ///< current frame number (not used for decoding)
212 GetBitContext gb; ///< bitstream reader context
213 int buf_bit_size; ///< buffer size in bits
214 uint8_t drc_gain; ///< gain for the DRC tool
215 int8_t skip_frame; ///< skip output step
216 int8_t parsed_all_subframes; ///< all subframes decoded?
218 /* subframe/block decode state */
219 int16_t subframe_len; ///< current subframe length
220 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
221 int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
222 int8_t num_bands; ///< number of scale factor bands
223 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
224 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
225 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
226 int8_t esc_len; ///< length of escaped coefficients
228 uint8_t num_chgroups; ///< number of channel groups
229 WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
231 WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
236 *@brief helper function to print the most important members of the context
239 static av_cold void dump_context(WMAProDecodeCtx *s)
241 #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
242 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
244 PRINT("ed sample bit depth", s->bits_per_sample);
245 PRINT_HEX("ed decode flags", s->decode_flags);
246 PRINT("samples per frame", s->samples_per_frame);
247 PRINT("log2 frame size", s->log2_frame_size);
248 PRINT("max num subframes", s->max_num_subframes);
249 PRINT("len prefix", s->len_prefix);
250 PRINT("num channels", s->avctx->channels);
254 *@brief Uninitialize the decoder and free all resources.
255 *@param avctx codec context
256 *@return 0 on success, < 0 otherwise
258 static av_cold int decode_end(AVCodecContext *avctx)
260 WMAProDecodeCtx *s = avctx->priv_data;
263 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
264 ff_mdct_end(&s->mdct_ctx[i]);
270 *@brief Initialize the decoder.
271 *@param avctx codec context
272 *@return 0 on success, -1 otherwise
274 static av_cold int decode_init(AVCodecContext *avctx)
276 WMAProDecodeCtx *s = avctx->priv_data;
277 uint8_t *edata_ptr = avctx->extradata;
278 unsigned int channel_mask;
280 int log2_max_num_subframes;
281 int num_possible_block_sizes;
284 ff_dsputil_init(&s->dsp, avctx);
285 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
287 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
289 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
291 if (avctx->extradata_size >= 18) {
292 s->decode_flags = AV_RL16(edata_ptr+14);
293 channel_mask = AV_RL32(edata_ptr+2);
294 s->bits_per_sample = AV_RL16(edata_ptr);
295 /** dump the extradata */
296 for (i = 0; i < avctx->extradata_size; i++)
297 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
298 av_dlog(avctx, "\n");
301 av_log_ask_for_sample(avctx, "Unknown extradata size\n");
302 return AVERROR_INVALIDDATA;
306 s->log2_frame_size = av_log2(avctx->block_align) + 4;
309 s->skip_frame = 1; /* skip first frame */
311 s->len_prefix = (s->decode_flags & 0x40);
314 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
315 if (bits > WMAPRO_BLOCK_MAX_BITS) {
316 av_log_missing_feature(avctx, "14-bits block sizes", 1);
317 return AVERROR_PATCHWELCOME;
319 s->samples_per_frame = 1 << bits;
322 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
323 s->max_num_subframes = 1 << log2_max_num_subframes;
324 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
325 s->max_subframe_len_bit = 1;
326 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
328 num_possible_block_sizes = log2_max_num_subframes + 1;
329 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
330 s->dynamic_range_compression = (s->decode_flags & 0x80);
332 if (s->max_num_subframes > MAX_SUBFRAMES) {
333 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
334 s->max_num_subframes);
335 return AVERROR_INVALIDDATA;
338 if (s->min_samples_per_subframe < (1<<WMAPRO_BLOCK_MIN_BITS)) {
339 av_log(avctx, AV_LOG_ERROR, "min_samples_per_subframe of %d too small\n",
340 s->min_samples_per_subframe);
341 return AVERROR_INVALIDDATA;
344 if (s->avctx->sample_rate <= 0) {
345 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
346 return AVERROR_INVALIDDATA;
349 if (avctx->channels < 0) {
350 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
352 return AVERROR_INVALIDDATA;
353 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
354 av_log_ask_for_sample(avctx, "unsupported number of channels\n");
355 return AVERROR_PATCHWELCOME;
358 /** init previous block len */
359 for (i = 0; i < avctx->channels; i++)
360 s->channel[i].prev_block_len = s->samples_per_frame;
362 /** extract lfe channel position */
365 if (channel_mask & 8) {
367 for (mask = 1; mask < 16; mask <<= 1) {
368 if (channel_mask & mask)
373 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
374 scale_huffbits, 1, 1,
375 scale_huffcodes, 2, 2, 616);
377 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
378 scale_rl_huffbits, 1, 1,
379 scale_rl_huffcodes, 4, 4, 1406);
381 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
382 coef0_huffbits, 1, 1,
383 coef0_huffcodes, 4, 4, 2108);
385 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
386 coef1_huffbits, 1, 1,
387 coef1_huffcodes, 4, 4, 3912);
389 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
391 vec4_huffcodes, 2, 2, 604);
393 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
395 vec2_huffcodes, 2, 2, 562);
397 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
399 vec1_huffcodes, 2, 2, 562);
401 /** calculate number of scale factor bands and their offsets
402 for every possible block size */
403 for (i = 0; i < num_possible_block_sizes; i++) {
404 int subframe_len = s->samples_per_frame >> i;
408 s->sfb_offsets[i][0] = 0;
410 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
411 int offset = (subframe_len * 2 * critical_freq[x])
412 / s->avctx->sample_rate + 2;
414 if (offset > s->sfb_offsets[i][band - 1])
415 s->sfb_offsets[i][band++] = offset;
417 s->sfb_offsets[i][band - 1] = subframe_len;
418 s->num_sfb[i] = band - 1;
419 if (s->num_sfb[i] <= 0) {
420 av_log(avctx, AV_LOG_ERROR, "num_sfb invalid\n");
421 return AVERROR_INVALIDDATA;
426 /** Scale factors can be shared between blocks of different size
427 as every block has a different scale factor band layout.
428 The matrix sf_offsets is needed to find the correct scale factor.
431 for (i = 0; i < num_possible_block_sizes; i++) {
433 for (b = 0; b < s->num_sfb[i]; b++) {
435 int offset = ((s->sfb_offsets[i][b]
436 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
437 for (x = 0; x < num_possible_block_sizes; x++) {
439 while (s->sfb_offsets[x][v + 1] << x < offset)
441 s->sf_offsets[i][x][b] = v;
446 /** init MDCT, FIXME: only init needed sizes */
447 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
448 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
449 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
450 / (1 << (s->bits_per_sample - 1)));
452 /** init MDCT windows: simple sinus window */
453 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
454 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
455 ff_init_ff_sine_windows(win_idx);
456 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
459 /** calculate subwoofer cutoff values */
460 for (i = 0; i < num_possible_block_sizes; i++) {
461 int block_size = s->samples_per_frame >> i;
462 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
463 / s->avctx->sample_rate;
464 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
467 /** calculate sine values for the decorrelation matrix */
468 for (i = 0; i < 33; i++)
469 sin64[i] = sin(i*M_PI / 64.0);
471 if (avctx->debug & FF_DEBUG_BITSTREAM)
474 avctx->channel_layout = channel_mask;
476 avcodec_get_frame_defaults(&s->frame);
477 avctx->coded_frame = &s->frame;
483 *@brief Decode the subframe length.
485 *@param offset sample offset in the frame
486 *@return decoded subframe length on success, < 0 in case of an error
488 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
490 int frame_len_shift = 0;
493 /** no need to read from the bitstream when only one length is possible */
494 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
495 return s->min_samples_per_subframe;
497 /** 1 bit indicates if the subframe is of maximum length */
498 if (s->max_subframe_len_bit) {
499 if (get_bits1(&s->gb))
500 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
502 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
504 subframe_len = s->samples_per_frame >> frame_len_shift;
506 /** sanity check the length */
507 if (subframe_len < s->min_samples_per_subframe ||
508 subframe_len > s->samples_per_frame) {
509 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
511 return AVERROR_INVALIDDATA;
517 *@brief Decode how the data in the frame is split into subframes.
518 * Every WMA frame contains the encoded data for a fixed number of
519 * samples per channel. The data for every channel might be split
520 * into several subframes. This function will reconstruct the list of
521 * subframes for every channel.
523 * If the subframes are not evenly split, the algorithm estimates the
524 * channels with the lowest number of total samples.
525 * Afterwards, for each of these channels a bit is read from the
526 * bitstream that indicates if the channel contains a subframe with the
527 * next subframe size that is going to be read from the bitstream or not.
528 * If a channel contains such a subframe, the subframe size gets added to
529 * the channel's subframe list.
530 * The algorithm repeats these steps until the frame is properly divided
531 * between the individual channels.
534 *@return 0 on success, < 0 in case of an error
536 static int decode_tilehdr(WMAProDecodeCtx *s)
538 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
539 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
540 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
541 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
542 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
545 /* Should never consume more than 3073 bits (256 iterations for the
546 * while loop when always the minimum amount of 128 samples is subtracted
547 * from missing samples in the 8 channel case).
548 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
551 /** reset tiling information */
552 for (c = 0; c < s->avctx->channels; c++)
553 s->channel[c].num_subframes = 0;
555 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
556 fixed_channel_layout = 1;
558 /** loop until the frame data is split between the subframes */
562 /** check which channels contain the subframe */
563 for (c = 0; c < s->avctx->channels; c++) {
564 if (num_samples[c] == min_channel_len) {
565 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
566 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
567 contains_subframe[c] = 1;
569 contains_subframe[c] = get_bits1(&s->gb);
571 contains_subframe[c] = 0;
574 /** get subframe length, subframe_len == 0 is not allowed */
575 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
576 return AVERROR_INVALIDDATA;
578 /** add subframes to the individual channels and find new min_channel_len */
579 min_channel_len += subframe_len;
580 for (c = 0; c < s->avctx->channels; c++) {
581 WMAProChannelCtx* chan = &s->channel[c];
583 if (contains_subframe[c]) {
584 if (chan->num_subframes >= MAX_SUBFRAMES) {
585 av_log(s->avctx, AV_LOG_ERROR,
586 "broken frame: num subframes > 31\n");
587 return AVERROR_INVALIDDATA;
589 chan->subframe_len[chan->num_subframes] = subframe_len;
590 num_samples[c] += subframe_len;
591 ++chan->num_subframes;
592 if (num_samples[c] > s->samples_per_frame) {
593 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
594 "channel len > samples_per_frame\n");
595 return AVERROR_INVALIDDATA;
597 } else if (num_samples[c] <= min_channel_len) {
598 if (num_samples[c] < min_channel_len) {
599 channels_for_cur_subframe = 0;
600 min_channel_len = num_samples[c];
602 ++channels_for_cur_subframe;
605 } while (min_channel_len < s->samples_per_frame);
607 for (c = 0; c < s->avctx->channels; c++) {
610 for (i = 0; i < s->channel[c].num_subframes; i++) {
611 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
612 " len %i\n", s->frame_num, c, i,
613 s->channel[c].subframe_len[i]);
614 s->channel[c].subframe_offset[i] = offset;
615 offset += s->channel[c].subframe_len[i];
623 *@brief Calculate a decorrelation matrix from the bitstream parameters.
624 *@param s codec context
625 *@param chgroup channel group for which the matrix needs to be calculated
627 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
628 WMAProChannelGrp *chgroup)
632 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
633 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
634 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
636 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
637 rotation_offset[i] = get_bits(&s->gb, 6);
639 for (i = 0; i < chgroup->num_channels; i++)
640 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
641 get_bits1(&s->gb) ? 1.0 : -1.0;
643 for (i = 1; i < chgroup->num_channels; i++) {
645 for (x = 0; x < i; x++) {
647 for (y = 0; y < i + 1; y++) {
648 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
649 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
650 int n = rotation_offset[offset + x];
656 cosv = sin64[32 - n];
658 sinv = sin64[64 - n];
659 cosv = -sin64[n - 32];
662 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
663 (v1 * sinv) - (v2 * cosv);
664 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
665 (v1 * cosv) + (v2 * sinv);
673 *@brief Decode channel transformation parameters
674 *@param s codec context
675 *@return 0 in case of success, < 0 in case of bitstream errors
677 static int decode_channel_transform(WMAProDecodeCtx* s)
680 /* should never consume more than 1921 bits for the 8 channel case
681 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
682 * + MAX_CHANNELS + MAX_BANDS + 1)
685 /** in the one channel case channel transforms are pointless */
687 if (s->avctx->channels > 1) {
688 int remaining_channels = s->channels_for_cur_subframe;
690 if (get_bits1(&s->gb)) {
691 av_log_ask_for_sample(s->avctx,
692 "unsupported channel transform bit\n");
693 return AVERROR_INVALIDDATA;
696 for (s->num_chgroups = 0; remaining_channels &&
697 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
698 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
699 float** channel_data = chgroup->channel_data;
700 chgroup->num_channels = 0;
701 chgroup->transform = 0;
703 /** decode channel mask */
704 if (remaining_channels > 2) {
705 for (i = 0; i < s->channels_for_cur_subframe; i++) {
706 int channel_idx = s->channel_indexes_for_cur_subframe[i];
707 if (!s->channel[channel_idx].grouped
708 && get_bits1(&s->gb)) {
709 ++chgroup->num_channels;
710 s->channel[channel_idx].grouped = 1;
711 *channel_data++ = s->channel[channel_idx].coeffs;
715 chgroup->num_channels = remaining_channels;
716 for (i = 0; i < s->channels_for_cur_subframe; i++) {
717 int channel_idx = s->channel_indexes_for_cur_subframe[i];
718 if (!s->channel[channel_idx].grouped)
719 *channel_data++ = s->channel[channel_idx].coeffs;
720 s->channel[channel_idx].grouped = 1;
724 /** decode transform type */
725 if (chgroup->num_channels == 2) {
726 if (get_bits1(&s->gb)) {
727 if (get_bits1(&s->gb)) {
728 av_log_ask_for_sample(s->avctx,
729 "unsupported channel transform type\n");
732 chgroup->transform = 1;
733 if (s->avctx->channels == 2) {
734 chgroup->decorrelation_matrix[0] = 1.0;
735 chgroup->decorrelation_matrix[1] = -1.0;
736 chgroup->decorrelation_matrix[2] = 1.0;
737 chgroup->decorrelation_matrix[3] = 1.0;
740 chgroup->decorrelation_matrix[0] = 0.70703125;
741 chgroup->decorrelation_matrix[1] = -0.70703125;
742 chgroup->decorrelation_matrix[2] = 0.70703125;
743 chgroup->decorrelation_matrix[3] = 0.70703125;
746 } else if (chgroup->num_channels > 2) {
747 if (get_bits1(&s->gb)) {
748 chgroup->transform = 1;
749 if (get_bits1(&s->gb)) {
750 decode_decorrelation_matrix(s, chgroup);
752 /** FIXME: more than 6 coupled channels not supported */
753 if (chgroup->num_channels > 6) {
754 av_log_ask_for_sample(s->avctx,
755 "coupled channels > 6\n");
757 memcpy(chgroup->decorrelation_matrix,
758 default_decorrelation[chgroup->num_channels],
759 chgroup->num_channels * chgroup->num_channels *
760 sizeof(*chgroup->decorrelation_matrix));
766 /** decode transform on / off */
767 if (chgroup->transform) {
768 if (!get_bits1(&s->gb)) {
770 /** transform can be enabled for individual bands */
771 for (i = 0; i < s->num_bands; i++) {
772 chgroup->transform_band[i] = get_bits1(&s->gb);
775 memset(chgroup->transform_band, 1, s->num_bands);
778 remaining_channels -= chgroup->num_channels;
785 *@brief Extract the coefficients from the bitstream.
786 *@param s codec context
787 *@param c current channel number
788 *@return 0 on success, < 0 in case of bitstream errors
790 static int decode_coeffs(WMAProDecodeCtx *s, int c)
792 /* Integers 0..15 as single-precision floats. The table saves a
793 costly int to float conversion, and storing the values as
794 integers allows fast sign-flipping. */
795 static const uint32_t fval_tab[16] = {
796 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
797 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
798 0x41000000, 0x41100000, 0x41200000, 0x41300000,
799 0x41400000, 0x41500000, 0x41600000, 0x41700000,
803 WMAProChannelCtx* ci = &s->channel[c];
810 av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
812 vlctable = get_bits1(&s->gb);
813 vlc = &coef_vlc[vlctable];
823 /** decode vector coefficients (consumes up to 167 bits per iteration for
824 4 vector coded large values) */
825 while ((s->transmit_num_vec_coeffs || !rl_mode) &&
826 (cur_coeff + 3 < ci->num_vec_coeffs)) {
831 idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
833 if (idx == HUFF_VEC4_SIZE - 1) {
834 for (i = 0; i < 4; i += 2) {
835 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
836 if (idx == HUFF_VEC2_SIZE - 1) {
838 v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
839 if (v0 == HUFF_VEC1_SIZE - 1)
840 v0 += ff_wma_get_large_val(&s->gb);
841 v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
842 if (v1 == HUFF_VEC1_SIZE - 1)
843 v1 += ff_wma_get_large_val(&s->gb);
844 vals[i ] = av_float2int(v0);
845 vals[i+1] = av_float2int(v1);
847 vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
848 vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
852 vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
853 vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
854 vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
855 vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
859 for (i = 0; i < 4; i++) {
861 uint32_t sign = get_bits1(&s->gb) - 1;
862 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
865 ci->coeffs[cur_coeff] = 0;
866 /** switch to run level mode when subframe_len / 128 zeros
867 were found in a row */
868 rl_mode |= (++num_zeros > s->subframe_len >> 8);
874 /** decode run level coded coefficients */
875 if (cur_coeff < s->subframe_len) {
876 memset(&ci->coeffs[cur_coeff], 0,
877 sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
878 if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
879 level, run, 1, ci->coeffs,
880 cur_coeff, s->subframe_len,
881 s->subframe_len, s->esc_len, 0))
882 return AVERROR_INVALIDDATA;
889 *@brief Extract scale factors from the bitstream.
890 *@param s codec context
891 *@return 0 on success, < 0 in case of bitstream errors
893 static int decode_scale_factors(WMAProDecodeCtx* s)
897 /** should never consume more than 5344 bits
898 * MAX_CHANNELS * (1 + MAX_BANDS * 23)
901 for (i = 0; i < s->channels_for_cur_subframe; i++) {
902 int c = s->channel_indexes_for_cur_subframe[i];
905 s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
906 sf_end = s->channel[c].scale_factors + s->num_bands;
908 /** resample scale factors for the new block size
909 * as the scale factors might need to be resampled several times
910 * before some new values are transmitted, a backup of the last
911 * transmitted scale factors is kept in saved_scale_factors
913 if (s->channel[c].reuse_sf) {
914 const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
916 for (b = 0; b < s->num_bands; b++)
917 s->channel[c].scale_factors[b] =
918 s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
921 if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
923 if (!s->channel[c].reuse_sf) {
925 /** decode DPCM coded scale factors */
926 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
927 val = 45 / s->channel[c].scale_factor_step;
928 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
929 val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
934 /** run level decode differences to the resampled factors */
935 for (i = 0; i < s->num_bands; i++) {
941 idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
944 uint32_t code = get_bits(&s->gb, 14);
946 sign = (code & 1) - 1;
947 skip = (code & 0x3f) >> 1;
948 } else if (idx == 1) {
951 skip = scale_rl_run[idx];
952 val = scale_rl_level[idx];
953 sign = get_bits1(&s->gb)-1;
957 if (i >= s->num_bands) {
958 av_log(s->avctx, AV_LOG_ERROR,
959 "invalid scale factor coding\n");
960 return AVERROR_INVALIDDATA;
962 s->channel[c].scale_factors[i] += (val ^ sign) - sign;
966 s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
967 s->channel[c].table_idx = s->table_idx;
968 s->channel[c].reuse_sf = 1;
971 /** calculate new scale factor maximum */
972 s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
973 for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
974 s->channel[c].max_scale_factor =
975 FFMAX(s->channel[c].max_scale_factor, *sf);
983 *@brief Reconstruct the individual channel data.
984 *@param s codec context
986 static void inverse_channel_transform(WMAProDecodeCtx *s)
990 for (i = 0; i < s->num_chgroups; i++) {
991 if (s->chgroup[i].transform) {
992 float data[WMAPRO_MAX_CHANNELS];
993 const int num_channels = s->chgroup[i].num_channels;
994 float** ch_data = s->chgroup[i].channel_data;
995 float** ch_end = ch_data + num_channels;
996 const int8_t* tb = s->chgroup[i].transform_band;
999 /** multichannel decorrelation */
1000 for (sfb = s->cur_sfb_offsets;
1001 sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
1004 /** multiply values with the decorrelation_matrix */
1005 for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
1006 const float* mat = s->chgroup[i].decorrelation_matrix;
1007 const float* data_end = data + num_channels;
1008 float* data_ptr = data;
1011 for (ch = ch_data; ch < ch_end; ch++)
1012 *data_ptr++ = (*ch)[y];
1014 for (ch = ch_data; ch < ch_end; ch++) {
1017 while (data_ptr < data_end)
1018 sum += *data_ptr++ * *mat++;
1023 } else if (s->avctx->channels == 2) {
1024 int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
1025 s->fdsp.vector_fmul_scalar(ch_data[0] + sfb[0],
1026 ch_data[0] + sfb[0],
1028 s->fdsp.vector_fmul_scalar(ch_data[1] + sfb[0],
1029 ch_data[1] + sfb[0],
1038 *@brief Apply sine window and reconstruct the output buffer.
1039 *@param s codec context
1041 static void wmapro_window(WMAProDecodeCtx *s)
1044 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1045 int c = s->channel_indexes_for_cur_subframe[i];
1047 int winlen = s->channel[c].prev_block_len;
1048 float* start = s->channel[c].coeffs - (winlen >> 1);
1050 if (s->subframe_len < winlen) {
1051 start += (winlen - s->subframe_len) >> 1;
1052 winlen = s->subframe_len;
1055 window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
1059 s->dsp.vector_fmul_window(start, start, start + winlen,
1062 s->channel[c].prev_block_len = s->subframe_len;
1067 *@brief Decode a single subframe (block).
1068 *@param s codec context
1069 *@return 0 on success, < 0 when decoding failed
1071 static int decode_subframe(WMAProDecodeCtx *s)
1073 int offset = s->samples_per_frame;
1074 int subframe_len = s->samples_per_frame;
1076 int total_samples = s->samples_per_frame * s->avctx->channels;
1077 int transmit_coeffs = 0;
1078 int cur_subwoofer_cutoff;
1080 s->subframe_offset = get_bits_count(&s->gb);
1082 /** reset channel context and find the next block offset and size
1083 == the next block of the channel with the smallest number of
1086 for (i = 0; i < s->avctx->channels; i++) {
1087 s->channel[i].grouped = 0;
1088 if (offset > s->channel[i].decoded_samples) {
1089 offset = s->channel[i].decoded_samples;
1091 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1096 "processing subframe with offset %i len %i\n", offset, subframe_len);
1098 /** get a list of all channels that contain the estimated block */
1099 s->channels_for_cur_subframe = 0;
1100 for (i = 0; i < s->avctx->channels; i++) {
1101 const int cur_subframe = s->channel[i].cur_subframe;
1102 /** subtract already processed samples */
1103 total_samples -= s->channel[i].decoded_samples;
1105 /** and count if there are multiple subframes that match our profile */
1106 if (offset == s->channel[i].decoded_samples &&
1107 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1108 total_samples -= s->channel[i].subframe_len[cur_subframe];
1109 s->channel[i].decoded_samples +=
1110 s->channel[i].subframe_len[cur_subframe];
1111 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1112 ++s->channels_for_cur_subframe;
1116 /** check if the frame will be complete after processing the
1119 s->parsed_all_subframes = 1;
1122 av_dlog(s->avctx, "subframe is part of %i channels\n",
1123 s->channels_for_cur_subframe);
1125 /** calculate number of scale factor bands and their offsets */
1126 s->table_idx = av_log2(s->samples_per_frame/subframe_len);
1127 s->num_bands = s->num_sfb[s->table_idx];
1128 s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
1129 cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
1131 /** configure the decoder for the current subframe */
1132 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1133 int c = s->channel_indexes_for_cur_subframe[i];
1135 s->channel[c].coeffs = &s->channel[c].out[(s->samples_per_frame >> 1)
1139 s->subframe_len = subframe_len;
1140 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1142 /** skip extended header if any */
1143 if (get_bits1(&s->gb)) {
1145 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1146 int len = get_bits(&s->gb, 4);
1147 num_fill_bits = (len ? get_bits(&s->gb, len) : 0) + 1;
1150 if (num_fill_bits >= 0) {
1151 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1152 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1153 return AVERROR_INVALIDDATA;
1156 skip_bits_long(&s->gb, num_fill_bits);
1160 /** no idea for what the following bit is used */
1161 if (get_bits1(&s->gb)) {
1162 av_log_ask_for_sample(s->avctx, "reserved bit set\n");
1163 return AVERROR_INVALIDDATA;
1167 if (decode_channel_transform(s) < 0)
1168 return AVERROR_INVALIDDATA;
1171 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1172 int c = s->channel_indexes_for_cur_subframe[i];
1173 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1174 transmit_coeffs = 1;
1177 av_assert0(s->subframe_len <= WMAPRO_BLOCK_MAX_SIZE);
1178 if (transmit_coeffs) {
1180 int quant_step = 90 * s->bits_per_sample >> 4;
1182 /** decode number of vector coded coefficients */
1183 if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
1184 int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
1185 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1186 int c = s->channel_indexes_for_cur_subframe[i];
1187 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
1188 if (num_vec_coeffs > s->subframe_len) {
1189 av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
1190 return AVERROR_INVALIDDATA;
1192 s->channel[c].num_vec_coeffs = num_vec_coeffs;
1195 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1196 int c = s->channel_indexes_for_cur_subframe[i];
1197 s->channel[c].num_vec_coeffs = s->subframe_len;
1200 /** decode quantization step */
1201 step = get_sbits(&s->gb, 6);
1203 if (step == -32 || step == 31) {
1204 const int sign = (step == 31) - 1;
1206 while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
1207 (step = get_bits(&s->gb, 5)) == 31) {
1210 quant_step += ((quant + step) ^ sign) - sign;
1212 if (quant_step < 0) {
1213 av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
1216 /** decode quantization step modifiers for every channel */
1218 if (s->channels_for_cur_subframe == 1) {
1219 s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
1221 int modifier_len = get_bits(&s->gb, 3);
1222 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1223 int c = s->channel_indexes_for_cur_subframe[i];
1224 s->channel[c].quant_step = quant_step;
1225 if (get_bits1(&s->gb)) {
1227 s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
1229 ++s->channel[c].quant_step;
1234 /** decode scale factors */
1235 if (decode_scale_factors(s) < 0)
1236 return AVERROR_INVALIDDATA;
1239 av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
1240 get_bits_count(&s->gb) - s->subframe_offset);
1242 /** parse coefficients */
1243 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1244 int c = s->channel_indexes_for_cur_subframe[i];
1245 if (s->channel[c].transmit_coefs &&
1246 get_bits_count(&s->gb) < s->num_saved_bits) {
1247 decode_coeffs(s, c);
1249 memset(s->channel[c].coeffs, 0,
1250 sizeof(*s->channel[c].coeffs) * subframe_len);
1253 av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
1254 get_bits_count(&s->gb) - s->subframe_offset);
1256 if (transmit_coeffs) {
1257 FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
1258 /** reconstruct the per channel data */
1259 inverse_channel_transform(s);
1260 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1261 int c = s->channel_indexes_for_cur_subframe[i];
1262 const int* sf = s->channel[c].scale_factors;
1265 if (c == s->lfe_channel)
1266 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
1267 (subframe_len - cur_subwoofer_cutoff));
1269 /** inverse quantization and rescaling */
1270 for (b = 0; b < s->num_bands; b++) {
1271 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
1272 const int exp = s->channel[c].quant_step -
1273 (s->channel[c].max_scale_factor - *sf++) *
1274 s->channel[c].scale_factor_step;
1275 const float quant = pow(10.0, exp / 20.0);
1276 int start = s->cur_sfb_offsets[b];
1277 s->fdsp.vector_fmul_scalar(s->tmp + start,
1278 s->channel[c].coeffs + start,
1279 quant, end - start);
1282 /** apply imdct (imdct_half == DCTIV with reverse) */
1283 mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
1287 /** window and overlapp-add */
1290 /** handled one subframe */
1291 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1292 int c = s->channel_indexes_for_cur_subframe[i];
1293 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1294 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1295 return AVERROR_INVALIDDATA;
1297 ++s->channel[c].cur_subframe;
1304 *@brief Decode one WMA frame.
1305 *@param s codec context
1306 *@return 0 if the trailer bit indicates that this is the last frame,
1307 * 1 if there are additional frames
1309 static int decode_frame(WMAProDecodeCtx *s, int *got_frame_ptr)
1311 AVCodecContext *avctx = s->avctx;
1312 GetBitContext* gb = &s->gb;
1313 int more_frames = 0;
1317 /** get frame length */
1319 len = get_bits(gb, s->log2_frame_size);
1321 av_dlog(s->avctx, "decoding frame with length %x\n", len);
1323 /** decode tile information */
1324 if (decode_tilehdr(s)) {
1329 /** read postproc transform */
1330 if (s->avctx->channels > 1 && get_bits1(gb)) {
1331 if (get_bits1(gb)) {
1332 for (i = 0; i < avctx->channels * avctx->channels; i++)
1337 /** read drc info */
1338 if (s->dynamic_range_compression) {
1339 s->drc_gain = get_bits(gb, 8);
1340 av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
1343 /** no idea what these are for, might be the number of samples
1344 that need to be skipped at the beginning or end of a stream */
1345 if (get_bits1(gb)) {
1348 /** usually true for the first frame */
1349 if (get_bits1(gb)) {
1350 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1351 av_dlog(s->avctx, "start skip: %i\n", skip);
1354 /** sometimes true for the last frame */
1355 if (get_bits1(gb)) {
1356 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1357 av_dlog(s->avctx, "end skip: %i\n", skip);
1362 av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
1363 get_bits_count(gb) - s->frame_offset);
1365 /** reset subframe states */
1366 s->parsed_all_subframes = 0;
1367 for (i = 0; i < avctx->channels; i++) {
1368 s->channel[i].decoded_samples = 0;
1369 s->channel[i].cur_subframe = 0;
1370 s->channel[i].reuse_sf = 0;
1373 /** decode all subframes */
1374 while (!s->parsed_all_subframes) {
1375 if (decode_subframe(s) < 0) {
1381 /* get output buffer */
1382 s->frame.nb_samples = s->samples_per_frame;
1383 if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
1384 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1389 /** copy samples to the output buffer */
1390 for (i = 0; i < avctx->channels; i++)
1391 memcpy(s->frame.extended_data[i], s->channel[i].out,
1392 s->samples_per_frame * sizeof(*s->channel[i].out));
1394 for (i = 0; i < avctx->channels; i++) {
1395 /** reuse second half of the IMDCT output for the next frame */
1396 memcpy(&s->channel[i].out[0],
1397 &s->channel[i].out[s->samples_per_frame],
1398 s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
1401 if (s->skip_frame) {
1408 if (s->len_prefix) {
1409 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1410 /** FIXME: not sure if this is always an error */
1411 av_log(s->avctx, AV_LOG_ERROR,
1412 "frame[%i] would have to skip %i bits\n", s->frame_num,
1413 len - (get_bits_count(gb) - s->frame_offset) - 1);
1418 /** skip the rest of the frame data */
1419 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1421 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1425 /** decode trailer bit */
1426 more_frames = get_bits1(gb);
1433 *@brief Calculate remaining input buffer length.
1434 *@param s codec context
1435 *@param gb bitstream reader context
1436 *@return remaining size in bits
1438 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1440 return s->buf_bit_size - get_bits_count(gb);
1444 *@brief Fill the bit reservoir with a (partial) frame.
1445 *@param s codec context
1446 *@param gb bitstream reader context
1447 *@param len length of the partial frame
1448 *@param append decides whether to reset the buffer or not
1450 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1455 /** when the frame data does not need to be concatenated, the input buffer
1456 is reset and additional bits from the previous frame are copied
1457 and skipped later so that a fast byte copy is possible */
1460 s->frame_offset = get_bits_count(gb) & 7;
1461 s->num_saved_bits = s->frame_offset;
1462 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1465 buflen = (put_bits_count(&s->pb) + len + 8) >> 3;
1467 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1468 av_log_ask_for_sample(s->avctx, "input buffer too small\n");
1473 s->num_saved_bits += len;
1475 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1478 int align = 8 - (get_bits_count(gb) & 7);
1479 align = FFMIN(align, len);
1480 put_bits(&s->pb, align, get_bits(gb, align));
1482 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1484 skip_bits_long(gb, len);
1487 PutBitContext tmp = s->pb;
1488 flush_put_bits(&tmp);
1491 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1492 skip_bits(&s->gb, s->frame_offset);
1496 *@brief Decode a single WMA packet.
1497 *@param avctx codec context
1498 *@param data the output buffer
1499 *@param avpkt input packet
1500 *@return number of bytes that were read from the input buffer
1502 static int decode_packet(AVCodecContext *avctx, void *data,
1503 int *got_frame_ptr, AVPacket* avpkt)
1505 WMAProDecodeCtx *s = avctx->priv_data;
1506 GetBitContext* gb = &s->pgb;
1507 const uint8_t* buf = avpkt->data;
1508 int buf_size = avpkt->size;
1509 int num_bits_prev_frame;
1510 int packet_sequence_number;
1514 if (s->packet_done || s->packet_loss) {
1517 /** sanity check for the buffer length */
1518 if (buf_size < avctx->block_align)
1521 s->next_packet_start = buf_size - avctx->block_align;
1522 buf_size = avctx->block_align;
1523 s->buf_bit_size = buf_size << 3;
1525 /** parse packet header */
1526 init_get_bits(gb, buf, s->buf_bit_size);
1527 packet_sequence_number = get_bits(gb, 4);
1530 /** get number of bits that need to be added to the previous frame */
1531 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1532 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1533 num_bits_prev_frame);
1535 /** check for packet loss */
1536 if (!s->packet_loss &&
1537 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1539 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
1540 s->packet_sequence_number, packet_sequence_number);
1542 s->packet_sequence_number = packet_sequence_number;
1544 if (num_bits_prev_frame > 0) {
1545 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1546 if (num_bits_prev_frame >= remaining_packet_bits) {
1547 num_bits_prev_frame = remaining_packet_bits;
1551 /** append the previous frame data to the remaining data from the
1552 previous packet to create a full frame */
1553 save_bits(s, gb, num_bits_prev_frame, 1);
1554 av_dlog(avctx, "accumulated %x bits of frame data\n",
1555 s->num_saved_bits - s->frame_offset);
1557 /** decode the cross packet frame if it is valid */
1558 if (!s->packet_loss)
1559 decode_frame(s, got_frame_ptr);
1560 } else if (s->num_saved_bits - s->frame_offset) {
1561 av_dlog(avctx, "ignoring %x previously saved bits\n",
1562 s->num_saved_bits - s->frame_offset);
1565 if (s->packet_loss) {
1566 /** reset number of saved bits so that the decoder
1567 does not start to decode incomplete frames in the
1568 s->len_prefix == 0 case */
1569 s->num_saved_bits = 0;
1575 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1576 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1577 skip_bits(gb, s->packet_offset);
1578 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1579 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1580 frame_size <= remaining_bits(s, gb)) {
1581 save_bits(s, gb, frame_size, 0);
1582 s->packet_done = !decode_frame(s, got_frame_ptr);
1583 } else if (!s->len_prefix
1584 && s->num_saved_bits > get_bits_count(&s->gb)) {
1585 /** when the frames do not have a length prefix, we don't know
1586 the compressed length of the individual frames
1587 however, we know what part of a new packet belongs to the
1589 therefore we save the incoming packet first, then we append
1590 the "previous frame" data from the next packet so that
1591 we get a buffer that only contains full frames */
1592 s->packet_done = !decode_frame(s, got_frame_ptr);
1597 if (s->packet_done && !s->packet_loss &&
1598 remaining_bits(s, gb) > 0) {
1599 /** save the rest of the data so that it can be decoded
1600 with the next packet */
1601 save_bits(s, gb, remaining_bits(s, gb), 0);
1604 s->packet_offset = get_bits_count(gb) & 7;
1606 return AVERROR_INVALIDDATA;
1609 *(AVFrame *)data = s->frame;
1611 return get_bits_count(gb) >> 3;
1615 *@brief Clear decoder buffers (for seeking).
1616 *@param avctx codec context
1618 static void flush(AVCodecContext *avctx)
1620 WMAProDecodeCtx *s = avctx->priv_data;
1622 /** reset output buffer as a part of it is used during the windowing of a
1624 for (i = 0; i < avctx->channels; i++)
1625 memset(s->channel[i].out, 0, s->samples_per_frame *
1626 sizeof(*s->channel[i].out));
1632 *@brief wmapro decoder
1634 AVCodec ff_wmapro_decoder = {
1636 .type = AVMEDIA_TYPE_AUDIO,
1637 .id = AV_CODEC_ID_WMAPRO,
1638 .priv_data_size = sizeof(WMAProDecodeCtx),
1639 .init = decode_init,
1640 .close = decode_end,
1641 .decode = decode_packet,
1642 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1644 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1645 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1646 AV_SAMPLE_FMT_NONE },