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 Libav.
8 * Libav 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 * Libav 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 Libav; 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.
91 #include "libavutil/float_dsp.h"
92 #include "libavutil/intfloat.h"
93 #include "libavutil/intreadwrite.h"
98 #include "wmaprodata.h"
101 #include "wma_common.h"
103 /** current decoder limitations */
104 #define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels
105 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
106 #define MAX_BANDS 29 ///< max number of scale factor bands
107 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
109 #define WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
110 #define WMAPRO_BLOCK_MAX_BITS 13 ///< log2 of max block size
111 #define WMAPRO_BLOCK_MIN_SIZE (1 << WMAPRO_BLOCK_MIN_BITS) ///< minimum block size
112 #define WMAPRO_BLOCK_MAX_SIZE (1 << WMAPRO_BLOCK_MAX_BITS) ///< maximum block size
113 #define WMAPRO_BLOCK_SIZES (WMAPRO_BLOCK_MAX_BITS - WMAPRO_BLOCK_MIN_BITS + 1) ///< possible block sizes
117 #define SCALEVLCBITS 8
118 #define VEC4MAXDEPTH ((HUFF_VEC4_MAXBITS+VLCBITS-1)/VLCBITS)
119 #define VEC2MAXDEPTH ((HUFF_VEC2_MAXBITS+VLCBITS-1)/VLCBITS)
120 #define VEC1MAXDEPTH ((HUFF_VEC1_MAXBITS+VLCBITS-1)/VLCBITS)
121 #define SCALEMAXDEPTH ((HUFF_SCALE_MAXBITS+SCALEVLCBITS-1)/SCALEVLCBITS)
122 #define SCALERLMAXDEPTH ((HUFF_SCALE_RL_MAXBITS+VLCBITS-1)/VLCBITS)
124 static VLC sf_vlc; ///< scale factor DPCM vlc
125 static VLC sf_rl_vlc; ///< scale factor run length vlc
126 static VLC vec4_vlc; ///< 4 coefficients per symbol
127 static VLC vec2_vlc; ///< 2 coefficients per symbol
128 static VLC vec1_vlc; ///< 1 coefficient per symbol
129 static VLC coef_vlc[2]; ///< coefficient run length vlc codes
130 static float sin64[33]; ///< sine table for decorrelation
133 * @brief frame specific decoder context for a single channel
136 int16_t prev_block_len; ///< length of the previous block
137 uint8_t transmit_coefs;
138 uint8_t num_subframes;
139 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
140 uint16_t subframe_offset[MAX_SUBFRAMES]; ///< subframe positions in the current frame
141 uint8_t cur_subframe; ///< current subframe number
142 uint16_t decoded_samples; ///< number of already processed samples
143 uint8_t grouped; ///< channel is part of a group
144 int quant_step; ///< quantization step for the current subframe
145 int8_t reuse_sf; ///< share scale factors between subframes
146 int8_t scale_factor_step; ///< scaling step for the current subframe
147 int max_scale_factor; ///< maximum scale factor for the current subframe
148 int saved_scale_factors[2][MAX_BANDS]; ///< resampled and (previously) transmitted scale factor values
149 int8_t scale_factor_idx; ///< index for the transmitted scale factor values (used for resampling)
150 int* scale_factors; ///< pointer to the scale factor values used for decoding
151 uint8_t table_idx; ///< index in sf_offsets for the scale factor reference block
152 float* coeffs; ///< pointer to the subframe decode buffer
153 uint16_t num_vec_coeffs; ///< number of vector coded coefficients
154 DECLARE_ALIGNED(32, float, out)[WMAPRO_BLOCK_MAX_SIZE + WMAPRO_BLOCK_MAX_SIZE / 2]; ///< output buffer
158 * @brief channel group for channel transformations
161 uint8_t num_channels; ///< number of channels in the group
162 int8_t transform; ///< transform on / off
163 int8_t transform_band[MAX_BANDS]; ///< controls if the transform is enabled for a certain band
164 float decorrelation_matrix[WMAPRO_MAX_CHANNELS*WMAPRO_MAX_CHANNELS];
165 float* channel_data[WMAPRO_MAX_CHANNELS]; ///< transformation coefficients
169 * @brief main decoder context
171 typedef struct WMAProDecodeCtx {
172 /* generic decoder variables */
173 AVCodecContext* avctx; ///< codec context for av_log
174 AVFloatDSPContext fdsp;
175 uint8_t frame_data[MAX_FRAMESIZE +
176 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
177 PutBitContext pb; ///< context for filling the frame_data buffer
178 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
179 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
180 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 = %"PRIx32"\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;
283 if (!avctx->block_align) {
284 av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
285 return AVERROR(EINVAL);
289 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
291 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
293 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
295 if (avctx->extradata_size >= 18) {
296 s->decode_flags = AV_RL16(edata_ptr+14);
297 channel_mask = AV_RL32(edata_ptr+2);
298 s->bits_per_sample = AV_RL16(edata_ptr);
299 /** dump the extradata */
300 for (i = 0; i < avctx->extradata_size; i++)
301 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
302 av_dlog(avctx, "\n");
305 avpriv_request_sample(avctx, "Unknown extradata size");
306 return AVERROR_PATCHWELCOME;
310 s->log2_frame_size = av_log2(avctx->block_align) + 4;
313 s->skip_frame = 1; /* skip first frame */
315 s->len_prefix = (s->decode_flags & 0x40);
318 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
319 if (bits > WMAPRO_BLOCK_MAX_BITS) {
320 avpriv_request_sample(avctx, "14-bit block sizes");
321 return AVERROR_PATCHWELCOME;
323 s->samples_per_frame = 1 << bits;
326 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
327 s->max_num_subframes = 1 << log2_max_num_subframes;
328 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
329 s->max_subframe_len_bit = 1;
330 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
332 num_possible_block_sizes = log2_max_num_subframes + 1;
333 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
334 s->dynamic_range_compression = (s->decode_flags & 0x80);
336 if (s->max_num_subframes > MAX_SUBFRAMES) {
337 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %"PRId8"\n",
338 s->max_num_subframes);
339 return AVERROR_INVALIDDATA;
342 if (s->min_samples_per_subframe < WMAPRO_BLOCK_MIN_SIZE) {
343 av_log(avctx, AV_LOG_ERROR, "Invalid minimum block size %"PRId8"\n",
344 s->max_num_subframes);
345 return AVERROR_INVALIDDATA;
348 if (s->avctx->sample_rate <= 0) {
349 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
350 return AVERROR_INVALIDDATA;
353 if (avctx->channels < 0) {
354 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
356 return AVERROR_INVALIDDATA;
357 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
358 avpriv_request_sample(avctx,
359 "More than %d channels", WMAPRO_MAX_CHANNELS);
360 return AVERROR_PATCHWELCOME;
363 /** init previous block len */
364 for (i = 0; i < avctx->channels; i++)
365 s->channel[i].prev_block_len = s->samples_per_frame;
367 /** extract lfe channel position */
370 if (channel_mask & 8) {
372 for (mask = 1; mask < 16; mask <<= 1) {
373 if (channel_mask & mask)
378 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
379 scale_huffbits, 1, 1,
380 scale_huffcodes, 2, 2, 616);
382 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
383 scale_rl_huffbits, 1, 1,
384 scale_rl_huffcodes, 4, 4, 1406);
386 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
387 coef0_huffbits, 1, 1,
388 coef0_huffcodes, 4, 4, 2108);
390 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
391 coef1_huffbits, 1, 1,
392 coef1_huffcodes, 4, 4, 3912);
394 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
396 vec4_huffcodes, 2, 2, 604);
398 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
400 vec2_huffcodes, 2, 2, 562);
402 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
404 vec1_huffcodes, 2, 2, 562);
406 /** calculate number of scale factor bands and their offsets
407 for every possible block size */
408 for (i = 0; i < num_possible_block_sizes; i++) {
409 int subframe_len = s->samples_per_frame >> i;
413 s->sfb_offsets[i][0] = 0;
415 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
416 int offset = (subframe_len * 2 * critical_freq[x])
417 / s->avctx->sample_rate + 2;
419 if (offset > s->sfb_offsets[i][band - 1])
420 s->sfb_offsets[i][band++] = offset;
422 s->sfb_offsets[i][band - 1] = subframe_len;
423 s->num_sfb[i] = band - 1;
427 /** Scale factors can be shared between blocks of different size
428 as every block has a different scale factor band layout.
429 The matrix sf_offsets is needed to find the correct scale factor.
432 for (i = 0; i < num_possible_block_sizes; i++) {
434 for (b = 0; b < s->num_sfb[i]; b++) {
436 int offset = ((s->sfb_offsets[i][b]
437 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
438 for (x = 0; x < num_possible_block_sizes; x++) {
440 while (s->sfb_offsets[x][v + 1] << x < offset)
441 if (++v >= MAX_BANDS)
442 return AVERROR_INVALIDDATA;
443 s->sf_offsets[i][x][b] = v;
448 /** init MDCT, FIXME: only init needed sizes */
449 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
450 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
451 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
452 / (1 << (s->bits_per_sample - 1)));
454 /** init MDCT windows: simple sine window */
455 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
456 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
457 ff_init_ff_sine_windows(win_idx);
458 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
461 /** calculate subwoofer cutoff values */
462 for (i = 0; i < num_possible_block_sizes; i++) {
463 int block_size = s->samples_per_frame >> i;
464 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
465 / s->avctx->sample_rate;
466 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
469 /** calculate sine values for the decorrelation matrix */
470 for (i = 0; i < 33; i++)
471 sin64[i] = sin(i*M_PI / 64.0);
473 if (avctx->debug & FF_DEBUG_BITSTREAM)
476 avctx->channel_layout = channel_mask;
482 *@brief Decode the subframe length.
484 *@param offset sample offset in the frame
485 *@return decoded subframe length on success, < 0 in case of an error
487 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
489 int frame_len_shift = 0;
492 /** no need to read from the bitstream when only one length is possible */
493 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
494 return s->min_samples_per_subframe;
496 /** 1 bit indicates if the subframe is of maximum length */
497 if (s->max_subframe_len_bit) {
498 if (get_bits1(&s->gb))
499 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
501 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
503 subframe_len = s->samples_per_frame >> frame_len_shift;
505 /** sanity check the length */
506 if (subframe_len < s->min_samples_per_subframe ||
507 subframe_len > s->samples_per_frame) {
508 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
510 return AVERROR_INVALIDDATA;
516 *@brief Decode how the data in the frame is split into subframes.
517 * Every WMA frame contains the encoded data for a fixed number of
518 * samples per channel. The data for every channel might be split
519 * into several subframes. This function will reconstruct the list of
520 * subframes for every channel.
522 * If the subframes are not evenly split, the algorithm estimates the
523 * channels with the lowest number of total samples.
524 * Afterwards, for each of these channels a bit is read from the
525 * bitstream that indicates if the channel contains a subframe with the
526 * next subframe size that is going to be read from the bitstream or not.
527 * If a channel contains such a subframe, the subframe size gets added to
528 * the channel's subframe list.
529 * The algorithm repeats these steps until the frame is properly divided
530 * between the individual channels.
533 *@return 0 on success, < 0 in case of an error
535 static int decode_tilehdr(WMAProDecodeCtx *s)
537 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
538 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
539 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
540 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
541 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
544 /* Should never consume more than 3073 bits (256 iterations for the
545 * while loop when always the minimum amount of 128 samples is subtracted
546 * from missing samples in the 8 channel case).
547 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
550 /** reset tiling information */
551 for (c = 0; c < s->avctx->channels; c++)
552 s->channel[c].num_subframes = 0;
554 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
555 fixed_channel_layout = 1;
557 /** loop until the frame data is split between the subframes */
561 /** check which channels contain the subframe */
562 for (c = 0; c < s->avctx->channels; c++) {
563 if (num_samples[c] == min_channel_len) {
564 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
565 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
566 contains_subframe[c] = 1;
568 contains_subframe[c] = get_bits1(&s->gb);
570 contains_subframe[c] = 0;
573 /** get subframe length, subframe_len == 0 is not allowed */
574 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
575 return AVERROR_INVALIDDATA;
577 /** add subframes to the individual channels and find new min_channel_len */
578 min_channel_len += subframe_len;
579 for (c = 0; c < s->avctx->channels; c++) {
580 WMAProChannelCtx* chan = &s->channel[c];
582 if (contains_subframe[c]) {
583 if (chan->num_subframes >= MAX_SUBFRAMES) {
584 av_log(s->avctx, AV_LOG_ERROR,
585 "broken frame: num subframes > 31\n");
586 return AVERROR_INVALIDDATA;
588 chan->subframe_len[chan->num_subframes] = subframe_len;
589 num_samples[c] += subframe_len;
590 ++chan->num_subframes;
591 if (num_samples[c] > s->samples_per_frame) {
592 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
593 "channel len > samples_per_frame\n");
594 return AVERROR_INVALIDDATA;
596 } else if (num_samples[c] <= min_channel_len) {
597 if (num_samples[c] < min_channel_len) {
598 channels_for_cur_subframe = 0;
599 min_channel_len = num_samples[c];
601 ++channels_for_cur_subframe;
604 } while (min_channel_len < s->samples_per_frame);
606 for (c = 0; c < s->avctx->channels; c++) {
609 for (i = 0; i < s->channel[c].num_subframes; i++) {
610 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
611 " len %i\n", s->frame_num, c, i,
612 s->channel[c].subframe_len[i]);
613 s->channel[c].subframe_offset[i] = offset;
614 offset += s->channel[c].subframe_len[i];
622 *@brief Calculate a decorrelation matrix from the bitstream parameters.
623 *@param s codec context
624 *@param chgroup channel group for which the matrix needs to be calculated
626 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
627 WMAProChannelGrp *chgroup)
631 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
632 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
633 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
635 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
636 rotation_offset[i] = get_bits(&s->gb, 6);
638 for (i = 0; i < chgroup->num_channels; i++)
639 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
640 get_bits1(&s->gb) ? 1.0 : -1.0;
642 for (i = 1; i < chgroup->num_channels; i++) {
644 for (x = 0; x < i; x++) {
646 for (y = 0; y < i + 1; y++) {
647 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
648 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
649 int n = rotation_offset[offset + x];
655 cosv = sin64[32 - n];
657 sinv = sin64[64 - n];
658 cosv = -sin64[n - 32];
661 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
662 (v1 * sinv) - (v2 * cosv);
663 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
664 (v1 * cosv) + (v2 * sinv);
672 *@brief Decode channel transformation parameters
673 *@param s codec context
674 *@return 0 in case of success, < 0 in case of bitstream errors
676 static int decode_channel_transform(WMAProDecodeCtx* s)
679 /* should never consume more than 1921 bits for the 8 channel case
680 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
681 * + MAX_CHANNELS + MAX_BANDS + 1)
684 /** in the one channel case channel transforms are pointless */
686 if (s->avctx->channels > 1) {
687 int remaining_channels = s->channels_for_cur_subframe;
689 if (get_bits1(&s->gb)) {
690 avpriv_request_sample(s->avctx,
691 "Channel transform bit");
692 return AVERROR_PATCHWELCOME;
695 for (s->num_chgroups = 0; remaining_channels &&
696 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
697 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
698 float** channel_data = chgroup->channel_data;
699 chgroup->num_channels = 0;
700 chgroup->transform = 0;
702 /** decode channel mask */
703 if (remaining_channels > 2) {
704 for (i = 0; i < s->channels_for_cur_subframe; i++) {
705 int channel_idx = s->channel_indexes_for_cur_subframe[i];
706 if (!s->channel[channel_idx].grouped
707 && get_bits1(&s->gb)) {
708 ++chgroup->num_channels;
709 s->channel[channel_idx].grouped = 1;
710 *channel_data++ = s->channel[channel_idx].coeffs;
714 chgroup->num_channels = remaining_channels;
715 for (i = 0; i < s->channels_for_cur_subframe; i++) {
716 int channel_idx = s->channel_indexes_for_cur_subframe[i];
717 if (!s->channel[channel_idx].grouped)
718 *channel_data++ = s->channel[channel_idx].coeffs;
719 s->channel[channel_idx].grouped = 1;
723 /** decode transform type */
724 if (chgroup->num_channels == 2) {
725 if (get_bits1(&s->gb)) {
726 if (get_bits1(&s->gb)) {
727 avpriv_request_sample(s->avctx,
728 "Unknown channel transform type");
729 return AVERROR_PATCHWELCOME;
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 avpriv_request_sample(s->avctx,
755 "Coupled channels > 6");
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->fdsp.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 offset += s->samples_per_frame >> 1;
1134 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1135 int c = s->channel_indexes_for_cur_subframe[i];
1137 s->channel[c].coeffs = &s->channel[c].out[offset];
1140 s->subframe_len = subframe_len;
1141 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1143 /** skip extended header if any */
1144 if (get_bits1(&s->gb)) {
1146 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1147 int len = get_bits(&s->gb, 4);
1148 num_fill_bits = get_bits(&s->gb, len) + 1;
1151 if (num_fill_bits >= 0) {
1152 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1153 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1154 return AVERROR_INVALIDDATA;
1157 skip_bits_long(&s->gb, num_fill_bits);
1161 /** no idea for what the following bit is used */
1162 if (get_bits1(&s->gb)) {
1163 avpriv_request_sample(s->avctx, "Reserved bit");
1164 return AVERROR_PATCHWELCOME;
1168 if (decode_channel_transform(s) < 0)
1169 return AVERROR_INVALIDDATA;
1172 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1173 int c = s->channel_indexes_for_cur_subframe[i];
1174 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1175 transmit_coeffs = 1;
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 + offset > FF_ARRAY_ELEMS(s->channel[c].out)) {
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, AVFrame *frame, 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 frame->nb_samples = s->samples_per_frame;
1383 if ((ret = ff_get_buffer(avctx, frame, 0)) < 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(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) {
1404 av_frame_unref(frame);
1409 if (s->len_prefix) {
1410 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1411 /** FIXME: not sure if this is always an error */
1412 av_log(s->avctx, AV_LOG_ERROR,
1413 "frame[%"PRIu32"] would have to skip %i bits\n",
1415 len - (get_bits_count(gb) - s->frame_offset) - 1);
1420 /** skip the rest of the frame data */
1421 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1423 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1427 /** decode trailer bit */
1428 more_frames = get_bits1(gb);
1435 *@brief Calculate remaining input buffer length.
1436 *@param s codec context
1437 *@param gb bitstream reader context
1438 *@return remaining size in bits
1440 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1442 return s->buf_bit_size - get_bits_count(gb);
1446 *@brief Fill the bit reservoir with a (partial) frame.
1447 *@param s codec context
1448 *@param gb bitstream reader context
1449 *@param len length of the partial frame
1450 *@param append decides whether to reset the buffer or not
1452 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1457 /** when the frame data does not need to be concatenated, the input buffer
1458 is resetted and additional bits from the previous frame are copyed
1459 and skipped later so that a fast byte copy is possible */
1462 s->frame_offset = get_bits_count(gb) & 7;
1463 s->num_saved_bits = s->frame_offset;
1464 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1467 buflen = (s->num_saved_bits + len + 8) >> 3;
1469 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1470 avpriv_request_sample(s->avctx, "Too small input buffer");
1475 if (len > put_bits_left(&s->pb)) {
1476 av_log(s->avctx, AV_LOG_ERROR,
1477 "Cannot append %d bits, only %d bits available.\n",
1478 len, put_bits_left(&s->pb));
1483 s->num_saved_bits += len;
1485 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1488 int align = 8 - (get_bits_count(gb) & 7);
1489 align = FFMIN(align, len);
1490 put_bits(&s->pb, align, get_bits(gb, align));
1492 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1494 skip_bits_long(gb, len);
1497 PutBitContext tmp = s->pb;
1498 flush_put_bits(&tmp);
1501 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1502 skip_bits(&s->gb, s->frame_offset);
1506 *@brief Decode a single WMA packet.
1507 *@param avctx codec context
1508 *@param data the output buffer
1509 *@param avpkt input packet
1510 *@return number of bytes that were read from the input buffer
1512 static int decode_packet(AVCodecContext *avctx, void *data,
1513 int *got_frame_ptr, AVPacket* avpkt)
1515 WMAProDecodeCtx *s = avctx->priv_data;
1516 GetBitContext* gb = &s->pgb;
1517 const uint8_t* buf = avpkt->data;
1518 int buf_size = avpkt->size;
1519 int num_bits_prev_frame;
1520 int packet_sequence_number;
1524 if (s->packet_done || s->packet_loss) {
1527 /** sanity check for the buffer length */
1528 if (buf_size < avctx->block_align) {
1529 av_log(avctx, AV_LOG_ERROR, "Input packet too small (%d < %d)\n",
1530 buf_size, avctx->block_align);
1531 return AVERROR_INVALIDDATA;
1534 s->next_packet_start = buf_size - avctx->block_align;
1535 buf_size = avctx->block_align;
1536 s->buf_bit_size = buf_size << 3;
1538 /** parse packet header */
1539 init_get_bits(gb, buf, s->buf_bit_size);
1540 packet_sequence_number = get_bits(gb, 4);
1543 /** get number of bits that need to be added to the previous frame */
1544 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1545 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1546 num_bits_prev_frame);
1548 /** check for packet loss */
1549 if (!s->packet_loss &&
1550 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1552 av_log(avctx, AV_LOG_ERROR,
1553 "Packet loss detected! seq %"PRIx8" vs %x\n",
1554 s->packet_sequence_number, packet_sequence_number);
1556 s->packet_sequence_number = packet_sequence_number;
1558 if (num_bits_prev_frame > 0) {
1559 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1560 if (num_bits_prev_frame >= remaining_packet_bits) {
1561 num_bits_prev_frame = remaining_packet_bits;
1565 /** append the previous frame data to the remaining data from the
1566 previous packet to create a full frame */
1567 save_bits(s, gb, num_bits_prev_frame, 1);
1568 av_dlog(avctx, "accumulated %x bits of frame data\n",
1569 s->num_saved_bits - s->frame_offset);
1571 /** decode the cross packet frame if it is valid */
1572 if (!s->packet_loss)
1573 decode_frame(s, data, got_frame_ptr);
1574 } else if (s->num_saved_bits - s->frame_offset) {
1575 av_dlog(avctx, "ignoring %x previously saved bits\n",
1576 s->num_saved_bits - s->frame_offset);
1579 if (s->packet_loss) {
1580 /** reset number of saved bits so that the decoder
1581 does not start to decode incomplete frames in the
1582 s->len_prefix == 0 case */
1583 s->num_saved_bits = 0;
1589 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1590 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1591 skip_bits(gb, s->packet_offset);
1592 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1593 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1594 frame_size <= remaining_bits(s, gb)) {
1595 save_bits(s, gb, frame_size, 0);
1596 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1597 } else if (!s->len_prefix
1598 && s->num_saved_bits > get_bits_count(&s->gb)) {
1599 /** when the frames do not have a length prefix, we don't know
1600 the compressed length of the individual frames
1601 however, we know what part of a new packet belongs to the
1603 therefore we save the incoming packet first, then we append
1604 the "previous frame" data from the next packet so that
1605 we get a buffer that only contains full frames */
1606 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1611 if (s->packet_done && !s->packet_loss &&
1612 remaining_bits(s, gb) > 0) {
1613 /** save the rest of the data so that it can be decoded
1614 with the next packet */
1615 save_bits(s, gb, remaining_bits(s, gb), 0);
1618 s->packet_offset = get_bits_count(gb) & 7;
1620 return AVERROR_INVALIDDATA;
1622 return get_bits_count(gb) >> 3;
1626 *@brief Clear decoder buffers (for seeking).
1627 *@param avctx codec context
1629 static void flush(AVCodecContext *avctx)
1631 WMAProDecodeCtx *s = avctx->priv_data;
1633 /** reset output buffer as a part of it is used during the windowing of a
1635 for (i = 0; i < avctx->channels; i++)
1636 memset(s->channel[i].out, 0, s->samples_per_frame *
1637 sizeof(*s->channel[i].out));
1643 *@brief wmapro decoder
1645 AVCodec ff_wmapro_decoder = {
1647 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1648 .type = AVMEDIA_TYPE_AUDIO,
1649 .id = AV_CODEC_ID_WMAPRO,
1650 .priv_data_size = sizeof(WMAProDecodeCtx),
1651 .init = decode_init,
1652 .close = decode_end,
1653 .decode = decode_packet,
1654 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1656 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1657 AV_SAMPLE_FMT_NONE },