2 * Wmapro compatible decoder
3 * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
4 * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * @brief wmapro decoder implementation
26 * Wmapro is an MDCT based codec comparable to wma standard or AAC.
27 * The decoding therefore consists of the following steps:
28 * - bitstream decoding
29 * - reconstruction of per-channel data
30 * - rescaling and inverse quantization
32 * - windowing and overlapp-add
34 * The compressed wmapro bitstream is split into individual packets.
35 * Every such packet contains one or more wma frames.
36 * The compressed frames may have a variable length and frames may
37 * cross packet boundaries.
38 * Common to all wmapro frames is the number of samples that are stored in
40 * The number of samples and a few other decode flags are stored
41 * as extradata that has to be passed to the decoder.
43 * The wmapro frames themselves are again split into a variable number of
44 * subframes. Every subframe contains the data for 2^N time domain samples
45 * where N varies between 7 and 12.
47 * Example wmapro bitstream (in samples):
49 * || packet 0 || packet 1 || packet 2 packets
50 * ---------------------------------------------------
51 * || frame 0 || frame 1 || frame 2 || frames
52 * ---------------------------------------------------
53 * || | | || | | | || || subframes of channel 0
54 * ---------------------------------------------------
55 * || | | || | | | || || subframes of channel 1
56 * ---------------------------------------------------
58 * The frame layouts for the individual channels of a wma frame does not need
61 * However, if the offsets and lengths of several subframes of a frame are the
62 * same, the subframes of the channels can be grouped.
63 * Every group may then use special coding techniques like M/S stereo coding
64 * to improve the compression ratio. These channel transformations do not
65 * need to be applied to a whole subframe. Instead, they can also work on
66 * individual scale factor bands (see below).
67 * The coefficients that carry the audio signal in the frequency domain
68 * are transmitted as huffman-coded vectors with 4, 2 and 1 elements.
69 * In addition to that, the encoder can switch to a runlevel coding scheme
70 * by transmitting subframe_length / 128 zero coefficients.
72 * Before the audio signal can be converted to the time domain, the
73 * coefficients have to be rescaled and inverse quantized.
74 * A subframe is therefore split into several scale factor bands that get
75 * scaled individually.
76 * Scale factors are submitted for every frame but they might be shared
77 * between the subframes of a channel. Scale factors are initially DPCM-coded.
78 * Once scale factors are shared, the differences are transmitted as runlevel
80 * Every subframe length and offset combination in the frame layout shares a
81 * common quantization factor that can be adjusted for every channel by a
83 * After the inverse quantization, the coefficients get processed by an IMDCT.
84 * The resulting values are then windowed with a sine window and the first half
85 * of the values are added to the second half of the output from the previous
86 * subframe in order to reconstruct the output samples.
89 #include "libavutil/float_dsp.h"
90 #include "libavutil/intfloat.h"
91 #include "libavutil/intreadwrite.h"
96 #include "wmaprodata.h"
99 #include "wma_common.h"
101 /** current decoder limitations */
102 #define WMAPRO_MAX_CHANNELS 8 ///< max number of handled channels
103 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
104 #define MAX_BANDS 29 ///< max number of scale factor bands
105 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
107 #define WMAPRO_BLOCK_MIN_BITS 6 ///< log2 of min block size
108 #define WMAPRO_BLOCK_MAX_BITS 13 ///< log2 of max block size
109 #define WMAPRO_BLOCK_MIN_SIZE (1 << WMAPRO_BLOCK_MIN_BITS) ///< minimum 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]; ///< sine 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 AVFloatDSPContext fdsp;
173 uint8_t frame_data[MAX_FRAMESIZE +
174 FF_INPUT_BUFFER_PADDING_SIZE];///< compressed frame data
175 PutBitContext pb; ///< context for filling the frame_data buffer
176 FFTContext mdct_ctx[WMAPRO_BLOCK_SIZES]; ///< MDCT context per block size
177 DECLARE_ALIGNED(32, float, tmp)[WMAPRO_BLOCK_MAX_SIZE]; ///< IMDCT output buffer
178 float* windows[WMAPRO_BLOCK_SIZES]; ///< windows for the different block sizes
180 /* frame size dependent frame information (set during initialization) */
181 uint32_t decode_flags; ///< used compression features
182 uint8_t len_prefix; ///< frame is prefixed with its length
183 uint8_t dynamic_range_compression; ///< frame contains DRC data
184 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
185 uint16_t samples_per_frame; ///< number of samples to output
186 uint16_t log2_frame_size;
187 int8_t lfe_channel; ///< lfe channel index
188 uint8_t max_num_subframes;
189 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
190 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
191 uint16_t min_samples_per_subframe;
192 int8_t num_sfb[WMAPRO_BLOCK_SIZES]; ///< scale factor bands per block size
193 int16_t sfb_offsets[WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor band offsets (multiples of 4)
194 int8_t sf_offsets[WMAPRO_BLOCK_SIZES][WMAPRO_BLOCK_SIZES][MAX_BANDS]; ///< scale factor resample matrix
195 int16_t subwoofer_cutoffs[WMAPRO_BLOCK_SIZES]; ///< subwoofer cutoff values
197 /* packet decode state */
198 GetBitContext pgb; ///< bitstream reader context for the packet
199 int next_packet_start; ///< start offset of the next wma packet in the demuxer packet
200 uint8_t packet_offset; ///< frame offset in the packet
201 uint8_t packet_sequence_number; ///< current packet number
202 int num_saved_bits; ///< saved number of bits
203 int frame_offset; ///< frame offset in the bit reservoir
204 int subframe_offset; ///< subframe offset in the bit reservoir
205 uint8_t packet_loss; ///< set in case of bitstream error
206 uint8_t packet_done; ///< set when a packet is fully decoded
208 /* frame decode state */
209 uint32_t frame_num; ///< current frame number (not used for decoding)
210 GetBitContext gb; ///< bitstream reader context
211 int buf_bit_size; ///< buffer size in bits
212 uint8_t drc_gain; ///< gain for the DRC tool
213 int8_t skip_frame; ///< skip output step
214 int8_t parsed_all_subframes; ///< all subframes decoded?
216 /* subframe/block decode state */
217 int16_t subframe_len; ///< current subframe length
218 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
219 int8_t channel_indexes_for_cur_subframe[WMAPRO_MAX_CHANNELS];
220 int8_t num_bands; ///< number of scale factor bands
221 int8_t transmit_num_vec_coeffs; ///< number of vector coded coefficients is part of the bitstream
222 int16_t* cur_sfb_offsets; ///< sfb offsets for the current block
223 uint8_t table_idx; ///< index for the num_sfb, sfb_offsets, sf_offsets and subwoofer_cutoffs tables
224 int8_t esc_len; ///< length of escaped coefficients
226 uint8_t num_chgroups; ///< number of channel groups
227 WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS]; ///< channel group information
229 WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS]; ///< per channel data
234 *@brief helper function to print the most important members of the context
237 static av_cold void dump_context(WMAProDecodeCtx *s)
239 #define PRINT(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %d\n", a, b);
240 #define PRINT_HEX(a, b) av_log(s->avctx, AV_LOG_DEBUG, " %s = %x\n", a, b);
242 PRINT("ed sample bit depth", s->bits_per_sample);
243 PRINT_HEX("ed decode flags", s->decode_flags);
244 PRINT("samples per frame", s->samples_per_frame);
245 PRINT("log2 frame size", s->log2_frame_size);
246 PRINT("max num subframes", s->max_num_subframes);
247 PRINT("len prefix", s->len_prefix);
248 PRINT("num channels", s->avctx->channels);
252 *@brief Uninitialize the decoder and free all resources.
253 *@param avctx codec context
254 *@return 0 on success, < 0 otherwise
256 static av_cold int decode_end(AVCodecContext *avctx)
258 WMAProDecodeCtx *s = avctx->priv_data;
261 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
262 ff_mdct_end(&s->mdct_ctx[i]);
268 *@brief Initialize the decoder.
269 *@param avctx codec context
270 *@return 0 on success, -1 otherwise
272 static av_cold int decode_init(AVCodecContext *avctx)
274 WMAProDecodeCtx *s = avctx->priv_data;
275 uint8_t *edata_ptr = avctx->extradata;
276 unsigned int channel_mask;
278 int log2_max_num_subframes;
279 int num_possible_block_sizes;
281 if (!avctx->block_align) {
282 av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
283 return AVERROR(EINVAL);
287 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
289 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
291 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
293 if (avctx->extradata_size >= 18) {
294 s->decode_flags = AV_RL16(edata_ptr+14);
295 channel_mask = AV_RL32(edata_ptr+2);
296 s->bits_per_sample = AV_RL16(edata_ptr);
297 /** dump the extradata */
298 for (i = 0; i < avctx->extradata_size; i++)
299 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
300 av_dlog(avctx, "\n");
303 avpriv_request_sample(avctx, "Unknown extradata size");
304 return AVERROR_PATCHWELCOME;
308 s->log2_frame_size = av_log2(avctx->block_align) + 4;
309 if (s->log2_frame_size > 25) {
310 avpriv_request_sample(avctx, "Large block align");
311 return AVERROR_PATCHWELCOME;
315 s->skip_frame = 1; /* skip first frame */
317 s->len_prefix = (s->decode_flags & 0x40);
320 bits = ff_wma_get_frame_len_bits(avctx->sample_rate, 3, s->decode_flags);
321 if (bits > WMAPRO_BLOCK_MAX_BITS) {
322 avpriv_request_sample(avctx, "14-bit block sizes");
323 return AVERROR_PATCHWELCOME;
325 s->samples_per_frame = 1 << bits;
328 log2_max_num_subframes = ((s->decode_flags & 0x38) >> 3);
329 s->max_num_subframes = 1 << log2_max_num_subframes;
330 if (s->max_num_subframes == 16 || s->max_num_subframes == 4)
331 s->max_subframe_len_bit = 1;
332 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
334 num_possible_block_sizes = log2_max_num_subframes + 1;
335 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
336 s->dynamic_range_compression = (s->decode_flags & 0x80);
338 if (s->max_num_subframes > MAX_SUBFRAMES) {
339 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
340 s->max_num_subframes);
341 return AVERROR_INVALIDDATA;
344 if (s->min_samples_per_subframe < WMAPRO_BLOCK_MIN_SIZE) {
345 av_log(avctx, AV_LOG_ERROR, "min_samples_per_subframe of %d too small\n",
346 s->min_samples_per_subframe);
347 return AVERROR_INVALIDDATA;
350 if (s->avctx->sample_rate <= 0) {
351 av_log(avctx, AV_LOG_ERROR, "invalid sample rate\n");
352 return AVERROR_INVALIDDATA;
355 if (avctx->channels < 0) {
356 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
358 return AVERROR_INVALIDDATA;
359 } else if (avctx->channels > WMAPRO_MAX_CHANNELS) {
360 avpriv_request_sample(avctx,
361 "More than %d channels", WMAPRO_MAX_CHANNELS);
362 return AVERROR_PATCHWELCOME;
365 /** init previous block len */
366 for (i = 0; i < avctx->channels; i++)
367 s->channel[i].prev_block_len = s->samples_per_frame;
369 /** extract lfe channel position */
372 if (channel_mask & 8) {
374 for (mask = 1; mask < 16; mask <<= 1) {
375 if (channel_mask & mask)
380 INIT_VLC_STATIC(&sf_vlc, SCALEVLCBITS, HUFF_SCALE_SIZE,
381 scale_huffbits, 1, 1,
382 scale_huffcodes, 2, 2, 616);
384 INIT_VLC_STATIC(&sf_rl_vlc, VLCBITS, HUFF_SCALE_RL_SIZE,
385 scale_rl_huffbits, 1, 1,
386 scale_rl_huffcodes, 4, 4, 1406);
388 INIT_VLC_STATIC(&coef_vlc[0], VLCBITS, HUFF_COEF0_SIZE,
389 coef0_huffbits, 1, 1,
390 coef0_huffcodes, 4, 4, 2108);
392 INIT_VLC_STATIC(&coef_vlc[1], VLCBITS, HUFF_COEF1_SIZE,
393 coef1_huffbits, 1, 1,
394 coef1_huffcodes, 4, 4, 3912);
396 INIT_VLC_STATIC(&vec4_vlc, VLCBITS, HUFF_VEC4_SIZE,
398 vec4_huffcodes, 2, 2, 604);
400 INIT_VLC_STATIC(&vec2_vlc, VLCBITS, HUFF_VEC2_SIZE,
402 vec2_huffcodes, 2, 2, 562);
404 INIT_VLC_STATIC(&vec1_vlc, VLCBITS, HUFF_VEC1_SIZE,
406 vec1_huffcodes, 2, 2, 562);
408 /** calculate number of scale factor bands and their offsets
409 for every possible block size */
410 for (i = 0; i < num_possible_block_sizes; i++) {
411 int subframe_len = s->samples_per_frame >> i;
415 s->sfb_offsets[i][0] = 0;
417 for (x = 0; x < MAX_BANDS-1 && s->sfb_offsets[i][band - 1] < subframe_len; x++) {
418 int offset = (subframe_len * 2 * critical_freq[x])
419 / s->avctx->sample_rate + 2;
421 if (offset > s->sfb_offsets[i][band - 1])
422 s->sfb_offsets[i][band++] = offset;
424 s->sfb_offsets[i][band - 1] = subframe_len;
425 s->num_sfb[i] = band - 1;
426 if (s->num_sfb[i] <= 0) {
427 av_log(avctx, AV_LOG_ERROR, "num_sfb invalid\n");
428 return AVERROR_INVALIDDATA;
433 /** Scale factors can be shared between blocks of different size
434 as every block has a different scale factor band layout.
435 The matrix sf_offsets is needed to find the correct scale factor.
438 for (i = 0; i < num_possible_block_sizes; i++) {
440 for (b = 0; b < s->num_sfb[i]; b++) {
442 int offset = ((s->sfb_offsets[i][b]
443 + s->sfb_offsets[i][b + 1] - 1) << i) >> 1;
444 for (x = 0; x < num_possible_block_sizes; x++) {
446 while (s->sfb_offsets[x][v + 1] << x < offset) {
448 av_assert0(v < MAX_BANDS);
450 s->sf_offsets[i][x][b] = v;
455 /** init MDCT, FIXME: only init needed sizes */
456 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++)
457 ff_mdct_init(&s->mdct_ctx[i], WMAPRO_BLOCK_MIN_BITS+1+i, 1,
458 1.0 / (1 << (WMAPRO_BLOCK_MIN_BITS + i - 1))
459 / (1 << (s->bits_per_sample - 1)));
461 /** init MDCT windows: simple sine window */
462 for (i = 0; i < WMAPRO_BLOCK_SIZES; i++) {
463 const int win_idx = WMAPRO_BLOCK_MAX_BITS - i;
464 ff_init_ff_sine_windows(win_idx);
465 s->windows[WMAPRO_BLOCK_SIZES - i - 1] = ff_sine_windows[win_idx];
468 /** calculate subwoofer cutoff values */
469 for (i = 0; i < num_possible_block_sizes; i++) {
470 int block_size = s->samples_per_frame >> i;
471 int cutoff = (440*block_size + 3 * (s->avctx->sample_rate >> 1) - 1)
472 / s->avctx->sample_rate;
473 s->subwoofer_cutoffs[i] = av_clip(cutoff, 4, block_size);
476 /** calculate sine values for the decorrelation matrix */
477 for (i = 0; i < 33; i++)
478 sin64[i] = sin(i*M_PI / 64.0);
480 if (avctx->debug & FF_DEBUG_BITSTREAM)
483 avctx->channel_layout = channel_mask;
489 *@brief Decode the subframe length.
491 *@param offset sample offset in the frame
492 *@return decoded subframe length on success, < 0 in case of an error
494 static int decode_subframe_length(WMAProDecodeCtx *s, int offset)
496 int frame_len_shift = 0;
499 /** no need to read from the bitstream when only one length is possible */
500 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
501 return s->min_samples_per_subframe;
503 /** 1 bit indicates if the subframe is of maximum length */
504 if (s->max_subframe_len_bit) {
505 if (get_bits1(&s->gb))
506 frame_len_shift = 1 + get_bits(&s->gb, s->subframe_len_bits-1);
508 frame_len_shift = get_bits(&s->gb, s->subframe_len_bits);
510 subframe_len = s->samples_per_frame >> frame_len_shift;
512 /** sanity check the length */
513 if (subframe_len < s->min_samples_per_subframe ||
514 subframe_len > s->samples_per_frame) {
515 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
517 return AVERROR_INVALIDDATA;
523 *@brief Decode how the data in the frame is split into subframes.
524 * Every WMA frame contains the encoded data for a fixed number of
525 * samples per channel. The data for every channel might be split
526 * into several subframes. This function will reconstruct the list of
527 * subframes for every channel.
529 * If the subframes are not evenly split, the algorithm estimates the
530 * channels with the lowest number of total samples.
531 * Afterwards, for each of these channels a bit is read from the
532 * bitstream that indicates if the channel contains a subframe with the
533 * next subframe size that is going to be read from the bitstream or not.
534 * If a channel contains such a subframe, the subframe size gets added to
535 * the channel's subframe list.
536 * The algorithm repeats these steps until the frame is properly divided
537 * between the individual channels.
540 *@return 0 on success, < 0 in case of an error
542 static int decode_tilehdr(WMAProDecodeCtx *s)
544 uint16_t num_samples[WMAPRO_MAX_CHANNELS] = { 0 };/**< sum of samples for all currently known subframes of a channel */
545 uint8_t contains_subframe[WMAPRO_MAX_CHANNELS]; /**< flag indicating if a channel contains the current subframe */
546 int channels_for_cur_subframe = s->avctx->channels; /**< number of channels that contain the current subframe */
547 int fixed_channel_layout = 0; /**< flag indicating that all channels use the same subframe offsets and sizes */
548 int min_channel_len = 0; /**< smallest sum of samples (channels with this length will be processed first) */
551 /* Should never consume more than 3073 bits (256 iterations for the
552 * while loop when always the minimum amount of 128 samples is subtracted
553 * from missing samples in the 8 channel case).
554 * 1 + BLOCK_MAX_SIZE * MAX_CHANNELS / BLOCK_MIN_SIZE * (MAX_CHANNELS + 4)
557 /** reset tiling information */
558 for (c = 0; c < s->avctx->channels; c++)
559 s->channel[c].num_subframes = 0;
561 if (s->max_num_subframes == 1 || get_bits1(&s->gb))
562 fixed_channel_layout = 1;
564 /** loop until the frame data is split between the subframes */
568 /** check which channels contain the subframe */
569 for (c = 0; c < s->avctx->channels; c++) {
570 if (num_samples[c] == min_channel_len) {
571 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
572 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe))
573 contains_subframe[c] = 1;
575 contains_subframe[c] = get_bits1(&s->gb);
577 contains_subframe[c] = 0;
580 /** get subframe length, subframe_len == 0 is not allowed */
581 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
582 return AVERROR_INVALIDDATA;
584 /** add subframes to the individual channels and find new min_channel_len */
585 min_channel_len += subframe_len;
586 for (c = 0; c < s->avctx->channels; c++) {
587 WMAProChannelCtx* chan = &s->channel[c];
589 if (contains_subframe[c]) {
590 if (chan->num_subframes >= MAX_SUBFRAMES) {
591 av_log(s->avctx, AV_LOG_ERROR,
592 "broken frame: num subframes > 31\n");
593 return AVERROR_INVALIDDATA;
595 chan->subframe_len[chan->num_subframes] = subframe_len;
596 num_samples[c] += subframe_len;
597 ++chan->num_subframes;
598 if (num_samples[c] > s->samples_per_frame) {
599 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
600 "channel len > samples_per_frame\n");
601 return AVERROR_INVALIDDATA;
603 } else if (num_samples[c] <= min_channel_len) {
604 if (num_samples[c] < min_channel_len) {
605 channels_for_cur_subframe = 0;
606 min_channel_len = num_samples[c];
608 ++channels_for_cur_subframe;
611 } while (min_channel_len < s->samples_per_frame);
613 for (c = 0; c < s->avctx->channels; c++) {
616 for (i = 0; i < s->channel[c].num_subframes; i++) {
617 av_dlog(s->avctx, "frame[%i] channel[%i] subframe[%i]"
618 " len %i\n", s->frame_num, c, i,
619 s->channel[c].subframe_len[i]);
620 s->channel[c].subframe_offset[i] = offset;
621 offset += s->channel[c].subframe_len[i];
629 *@brief Calculate a decorrelation matrix from the bitstream parameters.
630 *@param s codec context
631 *@param chgroup channel group for which the matrix needs to be calculated
633 static void decode_decorrelation_matrix(WMAProDecodeCtx *s,
634 WMAProChannelGrp *chgroup)
638 int8_t rotation_offset[WMAPRO_MAX_CHANNELS * WMAPRO_MAX_CHANNELS];
639 memset(chgroup->decorrelation_matrix, 0, s->avctx->channels *
640 s->avctx->channels * sizeof(*chgroup->decorrelation_matrix));
642 for (i = 0; i < chgroup->num_channels * (chgroup->num_channels - 1) >> 1; i++)
643 rotation_offset[i] = get_bits(&s->gb, 6);
645 for (i = 0; i < chgroup->num_channels; i++)
646 chgroup->decorrelation_matrix[chgroup->num_channels * i + i] =
647 get_bits1(&s->gb) ? 1.0 : -1.0;
649 for (i = 1; i < chgroup->num_channels; i++) {
651 for (x = 0; x < i; x++) {
653 for (y = 0; y < i + 1; y++) {
654 float v1 = chgroup->decorrelation_matrix[x * chgroup->num_channels + y];
655 float v2 = chgroup->decorrelation_matrix[i * chgroup->num_channels + y];
656 int n = rotation_offset[offset + x];
662 cosv = sin64[32 - n];
664 sinv = sin64[64 - n];
665 cosv = -sin64[n - 32];
668 chgroup->decorrelation_matrix[y + x * chgroup->num_channels] =
669 (v1 * sinv) - (v2 * cosv);
670 chgroup->decorrelation_matrix[y + i * chgroup->num_channels] =
671 (v1 * cosv) + (v2 * sinv);
679 *@brief Decode channel transformation parameters
680 *@param s codec context
681 *@return 0 in case of success, < 0 in case of bitstream errors
683 static int decode_channel_transform(WMAProDecodeCtx* s)
686 /* should never consume more than 1921 bits for the 8 channel case
687 * 1 + MAX_CHANNELS * (MAX_CHANNELS + 2 + 3 * MAX_CHANNELS * MAX_CHANNELS
688 * + MAX_CHANNELS + MAX_BANDS + 1)
691 /** in the one channel case channel transforms are pointless */
693 if (s->avctx->channels > 1) {
694 int remaining_channels = s->channels_for_cur_subframe;
696 if (get_bits1(&s->gb)) {
697 avpriv_request_sample(s->avctx,
698 "Channel transform bit");
699 return AVERROR_PATCHWELCOME;
702 for (s->num_chgroups = 0; remaining_channels &&
703 s->num_chgroups < s->channels_for_cur_subframe; s->num_chgroups++) {
704 WMAProChannelGrp* chgroup = &s->chgroup[s->num_chgroups];
705 float** channel_data = chgroup->channel_data;
706 chgroup->num_channels = 0;
707 chgroup->transform = 0;
709 /** decode channel mask */
710 if (remaining_channels > 2) {
711 for (i = 0; i < s->channels_for_cur_subframe; i++) {
712 int channel_idx = s->channel_indexes_for_cur_subframe[i];
713 if (!s->channel[channel_idx].grouped
714 && get_bits1(&s->gb)) {
715 ++chgroup->num_channels;
716 s->channel[channel_idx].grouped = 1;
717 *channel_data++ = s->channel[channel_idx].coeffs;
721 chgroup->num_channels = remaining_channels;
722 for (i = 0; i < s->channels_for_cur_subframe; i++) {
723 int channel_idx = s->channel_indexes_for_cur_subframe[i];
724 if (!s->channel[channel_idx].grouped)
725 *channel_data++ = s->channel[channel_idx].coeffs;
726 s->channel[channel_idx].grouped = 1;
730 /** decode transform type */
731 if (chgroup->num_channels == 2) {
732 if (get_bits1(&s->gb)) {
733 if (get_bits1(&s->gb)) {
734 avpriv_request_sample(s->avctx,
735 "Unknown channel transform type");
736 return AVERROR_PATCHWELCOME;
739 chgroup->transform = 1;
740 if (s->avctx->channels == 2) {
741 chgroup->decorrelation_matrix[0] = 1.0;
742 chgroup->decorrelation_matrix[1] = -1.0;
743 chgroup->decorrelation_matrix[2] = 1.0;
744 chgroup->decorrelation_matrix[3] = 1.0;
747 chgroup->decorrelation_matrix[0] = 0.70703125;
748 chgroup->decorrelation_matrix[1] = -0.70703125;
749 chgroup->decorrelation_matrix[2] = 0.70703125;
750 chgroup->decorrelation_matrix[3] = 0.70703125;
753 } else if (chgroup->num_channels > 2) {
754 if (get_bits1(&s->gb)) {
755 chgroup->transform = 1;
756 if (get_bits1(&s->gb)) {
757 decode_decorrelation_matrix(s, chgroup);
759 /** FIXME: more than 6 coupled channels not supported */
760 if (chgroup->num_channels > 6) {
761 avpriv_request_sample(s->avctx,
762 "Coupled channels > 6");
764 memcpy(chgroup->decorrelation_matrix,
765 default_decorrelation[chgroup->num_channels],
766 chgroup->num_channels * chgroup->num_channels *
767 sizeof(*chgroup->decorrelation_matrix));
773 /** decode transform on / off */
774 if (chgroup->transform) {
775 if (!get_bits1(&s->gb)) {
777 /** transform can be enabled for individual bands */
778 for (i = 0; i < s->num_bands; i++) {
779 chgroup->transform_band[i] = get_bits1(&s->gb);
782 memset(chgroup->transform_band, 1, s->num_bands);
785 remaining_channels -= chgroup->num_channels;
792 *@brief Extract the coefficients from the bitstream.
793 *@param s codec context
794 *@param c current channel number
795 *@return 0 on success, < 0 in case of bitstream errors
797 static int decode_coeffs(WMAProDecodeCtx *s, int c)
799 /* Integers 0..15 as single-precision floats. The table saves a
800 costly int to float conversion, and storing the values as
801 integers allows fast sign-flipping. */
802 static const uint32_t fval_tab[16] = {
803 0x00000000, 0x3f800000, 0x40000000, 0x40400000,
804 0x40800000, 0x40a00000, 0x40c00000, 0x40e00000,
805 0x41000000, 0x41100000, 0x41200000, 0x41300000,
806 0x41400000, 0x41500000, 0x41600000, 0x41700000,
810 WMAProChannelCtx* ci = &s->channel[c];
817 av_dlog(s->avctx, "decode coefficients for channel %i\n", c);
819 vlctable = get_bits1(&s->gb);
820 vlc = &coef_vlc[vlctable];
830 /** decode vector coefficients (consumes up to 167 bits per iteration for
831 4 vector coded large values) */
832 while ((s->transmit_num_vec_coeffs || !rl_mode) &&
833 (cur_coeff + 3 < ci->num_vec_coeffs)) {
838 idx = get_vlc2(&s->gb, vec4_vlc.table, VLCBITS, VEC4MAXDEPTH);
840 if (idx == HUFF_VEC4_SIZE - 1) {
841 for (i = 0; i < 4; i += 2) {
842 idx = get_vlc2(&s->gb, vec2_vlc.table, VLCBITS, VEC2MAXDEPTH);
843 if (idx == HUFF_VEC2_SIZE - 1) {
845 v0 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
846 if (v0 == HUFF_VEC1_SIZE - 1)
847 v0 += ff_wma_get_large_val(&s->gb);
848 v1 = get_vlc2(&s->gb, vec1_vlc.table, VLCBITS, VEC1MAXDEPTH);
849 if (v1 == HUFF_VEC1_SIZE - 1)
850 v1 += ff_wma_get_large_val(&s->gb);
851 vals[i ] = av_float2int(v0);
852 vals[i+1] = av_float2int(v1);
854 vals[i] = fval_tab[symbol_to_vec2[idx] >> 4 ];
855 vals[i+1] = fval_tab[symbol_to_vec2[idx] & 0xF];
859 vals[0] = fval_tab[ symbol_to_vec4[idx] >> 12 ];
860 vals[1] = fval_tab[(symbol_to_vec4[idx] >> 8) & 0xF];
861 vals[2] = fval_tab[(symbol_to_vec4[idx] >> 4) & 0xF];
862 vals[3] = fval_tab[ symbol_to_vec4[idx] & 0xF];
866 for (i = 0; i < 4; i++) {
868 uint32_t sign = get_bits1(&s->gb) - 1;
869 AV_WN32A(&ci->coeffs[cur_coeff], vals[i] ^ sign << 31);
872 ci->coeffs[cur_coeff] = 0;
873 /** switch to run level mode when subframe_len / 128 zeros
874 were found in a row */
875 rl_mode |= (++num_zeros > s->subframe_len >> 8);
881 /** decode run level coded coefficients */
882 if (cur_coeff < s->subframe_len) {
883 memset(&ci->coeffs[cur_coeff], 0,
884 sizeof(*ci->coeffs) * (s->subframe_len - cur_coeff));
885 if (ff_wma_run_level_decode(s->avctx, &s->gb, vlc,
886 level, run, 1, ci->coeffs,
887 cur_coeff, s->subframe_len,
888 s->subframe_len, s->esc_len, 0))
889 return AVERROR_INVALIDDATA;
896 *@brief Extract scale factors from the bitstream.
897 *@param s codec context
898 *@return 0 on success, < 0 in case of bitstream errors
900 static int decode_scale_factors(WMAProDecodeCtx* s)
904 /** should never consume more than 5344 bits
905 * MAX_CHANNELS * (1 + MAX_BANDS * 23)
908 for (i = 0; i < s->channels_for_cur_subframe; i++) {
909 int c = s->channel_indexes_for_cur_subframe[i];
912 s->channel[c].scale_factors = s->channel[c].saved_scale_factors[!s->channel[c].scale_factor_idx];
913 sf_end = s->channel[c].scale_factors + s->num_bands;
915 /** resample scale factors for the new block size
916 * as the scale factors might need to be resampled several times
917 * before some new values are transmitted, a backup of the last
918 * transmitted scale factors is kept in saved_scale_factors
920 if (s->channel[c].reuse_sf) {
921 const int8_t* sf_offsets = s->sf_offsets[s->table_idx][s->channel[c].table_idx];
923 for (b = 0; b < s->num_bands; b++)
924 s->channel[c].scale_factors[b] =
925 s->channel[c].saved_scale_factors[s->channel[c].scale_factor_idx][*sf_offsets++];
928 if (!s->channel[c].cur_subframe || get_bits1(&s->gb)) {
930 if (!s->channel[c].reuse_sf) {
932 /** decode DPCM coded scale factors */
933 s->channel[c].scale_factor_step = get_bits(&s->gb, 2) + 1;
934 val = 45 / s->channel[c].scale_factor_step;
935 for (sf = s->channel[c].scale_factors; sf < sf_end; sf++) {
936 val += get_vlc2(&s->gb, sf_vlc.table, SCALEVLCBITS, SCALEMAXDEPTH) - 60;
941 /** run level decode differences to the resampled factors */
942 for (i = 0; i < s->num_bands; i++) {
948 idx = get_vlc2(&s->gb, sf_rl_vlc.table, VLCBITS, SCALERLMAXDEPTH);
951 uint32_t code = get_bits(&s->gb, 14);
953 sign = (code & 1) - 1;
954 skip = (code & 0x3f) >> 1;
955 } else if (idx == 1) {
958 skip = scale_rl_run[idx];
959 val = scale_rl_level[idx];
960 sign = get_bits1(&s->gb)-1;
964 if (i >= s->num_bands) {
965 av_log(s->avctx, AV_LOG_ERROR,
966 "invalid scale factor coding\n");
967 return AVERROR_INVALIDDATA;
969 s->channel[c].scale_factors[i] += (val ^ sign) - sign;
973 s->channel[c].scale_factor_idx = !s->channel[c].scale_factor_idx;
974 s->channel[c].table_idx = s->table_idx;
975 s->channel[c].reuse_sf = 1;
978 /** calculate new scale factor maximum */
979 s->channel[c].max_scale_factor = s->channel[c].scale_factors[0];
980 for (sf = s->channel[c].scale_factors + 1; sf < sf_end; sf++) {
981 s->channel[c].max_scale_factor =
982 FFMAX(s->channel[c].max_scale_factor, *sf);
990 *@brief Reconstruct the individual channel data.
991 *@param s codec context
993 static void inverse_channel_transform(WMAProDecodeCtx *s)
997 for (i = 0; i < s->num_chgroups; i++) {
998 if (s->chgroup[i].transform) {
999 float data[WMAPRO_MAX_CHANNELS];
1000 const int num_channels = s->chgroup[i].num_channels;
1001 float** ch_data = s->chgroup[i].channel_data;
1002 float** ch_end = ch_data + num_channels;
1003 const int8_t* tb = s->chgroup[i].transform_band;
1006 /** multichannel decorrelation */
1007 for (sfb = s->cur_sfb_offsets;
1008 sfb < s->cur_sfb_offsets + s->num_bands; sfb++) {
1011 /** multiply values with the decorrelation_matrix */
1012 for (y = sfb[0]; y < FFMIN(sfb[1], s->subframe_len); y++) {
1013 const float* mat = s->chgroup[i].decorrelation_matrix;
1014 const float* data_end = data + num_channels;
1015 float* data_ptr = data;
1018 for (ch = ch_data; ch < ch_end; ch++)
1019 *data_ptr++ = (*ch)[y];
1021 for (ch = ch_data; ch < ch_end; ch++) {
1024 while (data_ptr < data_end)
1025 sum += *data_ptr++ * *mat++;
1030 } else if (s->avctx->channels == 2) {
1031 int len = FFMIN(sfb[1], s->subframe_len) - sfb[0];
1032 s->fdsp.vector_fmul_scalar(ch_data[0] + sfb[0],
1033 ch_data[0] + sfb[0],
1035 s->fdsp.vector_fmul_scalar(ch_data[1] + sfb[0],
1036 ch_data[1] + sfb[0],
1045 *@brief Apply sine window and reconstruct the output buffer.
1046 *@param s codec context
1048 static void wmapro_window(WMAProDecodeCtx *s)
1051 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1052 int c = s->channel_indexes_for_cur_subframe[i];
1054 int winlen = s->channel[c].prev_block_len;
1055 float* start = s->channel[c].coeffs - (winlen >> 1);
1057 if (s->subframe_len < winlen) {
1058 start += (winlen - s->subframe_len) >> 1;
1059 winlen = s->subframe_len;
1062 window = s->windows[av_log2(winlen) - WMAPRO_BLOCK_MIN_BITS];
1066 s->fdsp.vector_fmul_window(start, start, start + winlen,
1069 s->channel[c].prev_block_len = s->subframe_len;
1074 *@brief Decode a single subframe (block).
1075 *@param s codec context
1076 *@return 0 on success, < 0 when decoding failed
1078 static int decode_subframe(WMAProDecodeCtx *s)
1080 int offset = s->samples_per_frame;
1081 int subframe_len = s->samples_per_frame;
1083 int total_samples = s->samples_per_frame * s->avctx->channels;
1084 int transmit_coeffs = 0;
1085 int cur_subwoofer_cutoff;
1087 s->subframe_offset = get_bits_count(&s->gb);
1089 /** reset channel context and find the next block offset and size
1090 == the next block of the channel with the smallest number of
1093 for (i = 0; i < s->avctx->channels; i++) {
1094 s->channel[i].grouped = 0;
1095 if (offset > s->channel[i].decoded_samples) {
1096 offset = s->channel[i].decoded_samples;
1098 s->channel[i].subframe_len[s->channel[i].cur_subframe];
1103 "processing subframe with offset %i len %i\n", offset, subframe_len);
1105 /** get a list of all channels that contain the estimated block */
1106 s->channels_for_cur_subframe = 0;
1107 for (i = 0; i < s->avctx->channels; i++) {
1108 const int cur_subframe = s->channel[i].cur_subframe;
1109 /** subtract already processed samples */
1110 total_samples -= s->channel[i].decoded_samples;
1112 /** and count if there are multiple subframes that match our profile */
1113 if (offset == s->channel[i].decoded_samples &&
1114 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
1115 total_samples -= s->channel[i].subframe_len[cur_subframe];
1116 s->channel[i].decoded_samples +=
1117 s->channel[i].subframe_len[cur_subframe];
1118 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
1119 ++s->channels_for_cur_subframe;
1123 /** check if the frame will be complete after processing the
1126 s->parsed_all_subframes = 1;
1129 av_dlog(s->avctx, "subframe is part of %i channels\n",
1130 s->channels_for_cur_subframe);
1132 /** calculate number of scale factor bands and their offsets */
1133 s->table_idx = av_log2(s->samples_per_frame/subframe_len);
1134 s->num_bands = s->num_sfb[s->table_idx];
1135 s->cur_sfb_offsets = s->sfb_offsets[s->table_idx];
1136 cur_subwoofer_cutoff = s->subwoofer_cutoffs[s->table_idx];
1138 /** configure the decoder for the current subframe */
1139 offset += s->samples_per_frame >> 1;
1141 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1142 int c = s->channel_indexes_for_cur_subframe[i];
1144 s->channel[c].coeffs = &s->channel[c].out[offset];
1147 s->subframe_len = subframe_len;
1148 s->esc_len = av_log2(s->subframe_len - 1) + 1;
1150 /** skip extended header if any */
1151 if (get_bits1(&s->gb)) {
1153 if (!(num_fill_bits = get_bits(&s->gb, 2))) {
1154 int len = get_bits(&s->gb, 4);
1155 num_fill_bits = (len ? get_bits(&s->gb, len) : 0) + 1;
1158 if (num_fill_bits >= 0) {
1159 if (get_bits_count(&s->gb) + num_fill_bits > s->num_saved_bits) {
1160 av_log(s->avctx, AV_LOG_ERROR, "invalid number of fill bits\n");
1161 return AVERROR_INVALIDDATA;
1164 skip_bits_long(&s->gb, num_fill_bits);
1168 /** no idea for what the following bit is used */
1169 if (get_bits1(&s->gb)) {
1170 avpriv_request_sample(s->avctx, "Reserved bit");
1171 return AVERROR_PATCHWELCOME;
1175 if (decode_channel_transform(s) < 0)
1176 return AVERROR_INVALIDDATA;
1179 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1180 int c = s->channel_indexes_for_cur_subframe[i];
1181 if ((s->channel[c].transmit_coefs = get_bits1(&s->gb)))
1182 transmit_coeffs = 1;
1185 av_assert0(s->subframe_len <= WMAPRO_BLOCK_MAX_SIZE);
1186 if (transmit_coeffs) {
1188 int quant_step = 90 * s->bits_per_sample >> 4;
1190 /** decode number of vector coded coefficients */
1191 if ((s->transmit_num_vec_coeffs = get_bits1(&s->gb))) {
1192 int num_bits = av_log2((s->subframe_len + 3)/4) + 1;
1193 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1194 int c = s->channel_indexes_for_cur_subframe[i];
1195 int num_vec_coeffs = get_bits(&s->gb, num_bits) << 2;
1196 if (num_vec_coeffs > s->subframe_len) {
1197 av_log(s->avctx, AV_LOG_ERROR, "num_vec_coeffs %d is too large\n", num_vec_coeffs);
1198 return AVERROR_INVALIDDATA;
1200 av_assert0(num_vec_coeffs + offset <= FF_ARRAY_ELEMS(s->channel[c].out));
1201 s->channel[c].num_vec_coeffs = num_vec_coeffs;
1204 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1205 int c = s->channel_indexes_for_cur_subframe[i];
1206 s->channel[c].num_vec_coeffs = s->subframe_len;
1209 /** decode quantization step */
1210 step = get_sbits(&s->gb, 6);
1212 if (step == -32 || step == 31) {
1213 const int sign = (step == 31) - 1;
1215 while (get_bits_count(&s->gb) + 5 < s->num_saved_bits &&
1216 (step = get_bits(&s->gb, 5)) == 31) {
1219 quant_step += ((quant + step) ^ sign) - sign;
1221 if (quant_step < 0) {
1222 av_log(s->avctx, AV_LOG_DEBUG, "negative quant step\n");
1225 /** decode quantization step modifiers for every channel */
1227 if (s->channels_for_cur_subframe == 1) {
1228 s->channel[s->channel_indexes_for_cur_subframe[0]].quant_step = quant_step;
1230 int modifier_len = get_bits(&s->gb, 3);
1231 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1232 int c = s->channel_indexes_for_cur_subframe[i];
1233 s->channel[c].quant_step = quant_step;
1234 if (get_bits1(&s->gb)) {
1236 s->channel[c].quant_step += get_bits(&s->gb, modifier_len) + 1;
1238 ++s->channel[c].quant_step;
1243 /** decode scale factors */
1244 if (decode_scale_factors(s) < 0)
1245 return AVERROR_INVALIDDATA;
1248 av_dlog(s->avctx, "BITSTREAM: subframe header length was %i\n",
1249 get_bits_count(&s->gb) - s->subframe_offset);
1251 /** parse coefficients */
1252 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1253 int c = s->channel_indexes_for_cur_subframe[i];
1254 if (s->channel[c].transmit_coefs &&
1255 get_bits_count(&s->gb) < s->num_saved_bits) {
1256 decode_coeffs(s, c);
1258 memset(s->channel[c].coeffs, 0,
1259 sizeof(*s->channel[c].coeffs) * subframe_len);
1262 av_dlog(s->avctx, "BITSTREAM: subframe length was %i\n",
1263 get_bits_count(&s->gb) - s->subframe_offset);
1265 if (transmit_coeffs) {
1266 FFTContext *mdct = &s->mdct_ctx[av_log2(subframe_len) - WMAPRO_BLOCK_MIN_BITS];
1267 /** reconstruct the per channel data */
1268 inverse_channel_transform(s);
1269 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1270 int c = s->channel_indexes_for_cur_subframe[i];
1271 const int* sf = s->channel[c].scale_factors;
1274 if (c == s->lfe_channel)
1275 memset(&s->tmp[cur_subwoofer_cutoff], 0, sizeof(*s->tmp) *
1276 (subframe_len - cur_subwoofer_cutoff));
1278 /** inverse quantization and rescaling */
1279 for (b = 0; b < s->num_bands; b++) {
1280 const int end = FFMIN(s->cur_sfb_offsets[b+1], s->subframe_len);
1281 const int exp = s->channel[c].quant_step -
1282 (s->channel[c].max_scale_factor - *sf++) *
1283 s->channel[c].scale_factor_step;
1284 const float quant = pow(10.0, exp / 20.0);
1285 int start = s->cur_sfb_offsets[b];
1286 s->fdsp.vector_fmul_scalar(s->tmp + start,
1287 s->channel[c].coeffs + start,
1288 quant, end - start);
1291 /** apply imdct (imdct_half == DCTIV with reverse) */
1292 mdct->imdct_half(mdct, s->channel[c].coeffs, s->tmp);
1296 /** window and overlapp-add */
1299 /** handled one subframe */
1300 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1301 int c = s->channel_indexes_for_cur_subframe[i];
1302 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1303 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1304 return AVERROR_INVALIDDATA;
1306 ++s->channel[c].cur_subframe;
1313 *@brief Decode one WMA frame.
1314 *@param s codec context
1315 *@return 0 if the trailer bit indicates that this is the last frame,
1316 * 1 if there are additional frames
1318 static int decode_frame(WMAProDecodeCtx *s, AVFrame *frame, int *got_frame_ptr)
1320 AVCodecContext *avctx = s->avctx;
1321 GetBitContext* gb = &s->gb;
1322 int more_frames = 0;
1326 /** get frame length */
1328 len = get_bits(gb, s->log2_frame_size);
1330 av_dlog(s->avctx, "decoding frame with length %x\n", len);
1332 /** decode tile information */
1333 if (decode_tilehdr(s)) {
1338 /** read postproc transform */
1339 if (s->avctx->channels > 1 && get_bits1(gb)) {
1340 if (get_bits1(gb)) {
1341 for (i = 0; i < avctx->channels * avctx->channels; i++)
1346 /** read drc info */
1347 if (s->dynamic_range_compression) {
1348 s->drc_gain = get_bits(gb, 8);
1349 av_dlog(s->avctx, "drc_gain %i\n", s->drc_gain);
1352 /** no idea what these are for, might be the number of samples
1353 that need to be skipped at the beginning or end of a stream */
1354 if (get_bits1(gb)) {
1357 /** usually true for the first frame */
1358 if (get_bits1(gb)) {
1359 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1360 av_dlog(s->avctx, "start skip: %i\n", skip);
1363 /** sometimes true for the last frame */
1364 if (get_bits1(gb)) {
1365 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1366 av_dlog(s->avctx, "end skip: %i\n", skip);
1371 av_dlog(s->avctx, "BITSTREAM: frame header length was %i\n",
1372 get_bits_count(gb) - s->frame_offset);
1374 /** reset subframe states */
1375 s->parsed_all_subframes = 0;
1376 for (i = 0; i < avctx->channels; i++) {
1377 s->channel[i].decoded_samples = 0;
1378 s->channel[i].cur_subframe = 0;
1379 s->channel[i].reuse_sf = 0;
1382 /** decode all subframes */
1383 while (!s->parsed_all_subframes) {
1384 if (decode_subframe(s) < 0) {
1390 /* get output buffer */
1391 frame->nb_samples = s->samples_per_frame;
1392 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
1397 /** copy samples to the output buffer */
1398 for (i = 0; i < avctx->channels; i++)
1399 memcpy(frame->extended_data[i], s->channel[i].out,
1400 s->samples_per_frame * sizeof(*s->channel[i].out));
1402 for (i = 0; i < avctx->channels; i++) {
1403 /** reuse second half of the IMDCT output for the next frame */
1404 memcpy(&s->channel[i].out[0],
1405 &s->channel[i].out[s->samples_per_frame],
1406 s->samples_per_frame * sizeof(*s->channel[i].out) >> 1);
1409 if (s->skip_frame) {
1412 av_frame_unref(frame);
1417 if (s->len_prefix) {
1418 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1419 /** FIXME: not sure if this is always an error */
1420 av_log(s->avctx, AV_LOG_ERROR,
1421 "frame[%i] would have to skip %i bits\n", s->frame_num,
1422 len - (get_bits_count(gb) - s->frame_offset) - 1);
1427 /** skip the rest of the frame data */
1428 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1430 while (get_bits_count(gb) < s->num_saved_bits && get_bits1(gb) == 0) {
1434 /** decode trailer bit */
1435 more_frames = get_bits1(gb);
1442 *@brief Calculate remaining input buffer length.
1443 *@param s codec context
1444 *@param gb bitstream reader context
1445 *@return remaining size in bits
1447 static int remaining_bits(WMAProDecodeCtx *s, GetBitContext *gb)
1449 return s->buf_bit_size - get_bits_count(gb);
1453 *@brief Fill the bit reservoir with a (partial) frame.
1454 *@param s codec context
1455 *@param gb bitstream reader context
1456 *@param len length of the partial frame
1457 *@param append decides whether to reset the buffer or not
1459 static void save_bits(WMAProDecodeCtx *s, GetBitContext* gb, int len,
1464 /** when the frame data does not need to be concatenated, the input buffer
1465 is reset and additional bits from the previous frame are copied
1466 and skipped later so that a fast byte copy is possible */
1469 s->frame_offset = get_bits_count(gb) & 7;
1470 s->num_saved_bits = s->frame_offset;
1471 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1474 buflen = (put_bits_count(&s->pb) + len + 8) >> 3;
1476 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1477 avpriv_request_sample(s->avctx, "Too small input buffer");
1482 av_assert0(len <= put_bits_left(&s->pb));
1484 s->num_saved_bits += len;
1486 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1489 int align = 8 - (get_bits_count(gb) & 7);
1490 align = FFMIN(align, len);
1491 put_bits(&s->pb, align, get_bits(gb, align));
1493 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1495 skip_bits_long(gb, len);
1498 PutBitContext tmp = s->pb;
1499 flush_put_bits(&tmp);
1502 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1503 skip_bits(&s->gb, s->frame_offset);
1507 *@brief Decode a single WMA packet.
1508 *@param avctx codec context
1509 *@param data the output buffer
1510 *@param avpkt input packet
1511 *@return number of bytes that were read from the input buffer
1513 static int decode_packet(AVCodecContext *avctx, void *data,
1514 int *got_frame_ptr, AVPacket* avpkt)
1516 WMAProDecodeCtx *s = avctx->priv_data;
1517 GetBitContext* gb = &s->pgb;
1518 const uint8_t* buf = avpkt->data;
1519 int buf_size = avpkt->size;
1520 int num_bits_prev_frame;
1521 int packet_sequence_number;
1525 if (s->packet_done || s->packet_loss) {
1528 /** sanity check for the buffer length */
1529 if (buf_size < avctx->block_align) {
1530 av_log(avctx, AV_LOG_ERROR, "Input packet too small (%d < %d)\n",
1531 buf_size, avctx->block_align);
1532 return AVERROR_INVALIDDATA;
1535 s->next_packet_start = buf_size - avctx->block_align;
1536 buf_size = avctx->block_align;
1537 s->buf_bit_size = buf_size << 3;
1539 /** parse packet header */
1540 init_get_bits(gb, buf, s->buf_bit_size);
1541 packet_sequence_number = get_bits(gb, 4);
1544 /** get number of bits that need to be added to the previous frame */
1545 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1546 av_dlog(avctx, "packet[%d]: nbpf %x\n", avctx->frame_number,
1547 num_bits_prev_frame);
1549 /** check for packet loss */
1550 if (!s->packet_loss &&
1551 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1553 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x 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 if (!s->packet_loss)
1597 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1598 } else if (!s->len_prefix
1599 && s->num_saved_bits > get_bits_count(&s->gb)) {
1600 /** when the frames do not have a length prefix, we don't know
1601 the compressed length of the individual frames
1602 however, we know what part of a new packet belongs to the
1604 therefore we save the incoming packet first, then we append
1605 the "previous frame" data from the next packet so that
1606 we get a buffer that only contains full frames */
1607 s->packet_done = !decode_frame(s, data, got_frame_ptr);
1612 if (s->packet_done && !s->packet_loss &&
1613 remaining_bits(s, gb) > 0) {
1614 /** save the rest of the data so that it can be decoded
1615 with the next packet */
1616 save_bits(s, gb, remaining_bits(s, gb), 0);
1619 s->packet_offset = get_bits_count(gb) & 7;
1621 return AVERROR_INVALIDDATA;
1623 return get_bits_count(gb) >> 3;
1627 *@brief Clear decoder buffers (for seeking).
1628 *@param avctx codec context
1630 static void flush(AVCodecContext *avctx)
1632 WMAProDecodeCtx *s = avctx->priv_data;
1634 /** reset output buffer as a part of it is used during the windowing of a
1636 for (i = 0; i < avctx->channels; i++)
1637 memset(s->channel[i].out, 0, s->samples_per_frame *
1638 sizeof(*s->channel[i].out));
1644 *@brief wmapro decoder
1646 AVCodec ff_wmapro_decoder = {
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 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 9 Professional"),
1657 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1658 AV_SAMPLE_FMT_NONE },