2 * Windows Media Audio Lossless decoder
3 * Copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
4 * Copyright (c) 2008 - 2011 Sascha Sommer, Benjamin Larsson
5 * Copyright (c) 2011 Andreas Ă–man
6 * Copyright (c) 2011 - 2012 Mashiat Sarker Shakkhar
8 * This file is part of FFmpeg.
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "libavutil/attributes.h"
28 #include "libavutil/avassert.h"
34 #include "lossless_audiodsp.h"
36 #include "wma_common.h"
38 /** current decoder limitations */
39 #define WMALL_MAX_CHANNELS 8 ///< max number of handled channels
40 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
41 #define MAX_BANDS 29 ///< max number of scale factor bands
42 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
45 #define WMALL_BLOCK_MIN_BITS 6 ///< log2 of min block size
46 #define WMALL_BLOCK_MAX_BITS 14 ///< log2 of max block size
47 #define WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS) ///< maximum block size
48 #define WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1) ///< possible block sizes
50 #define WMALL_COEFF_PAD_SIZE 16 ///< pad coef buffers with 0 for use with SIMD
53 * @brief frame-specific decoder context for a single channel
56 int16_t prev_block_len; ///< length of the previous block
57 uint8_t transmit_coefs;
58 uint8_t num_subframes;
59 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
60 uint16_t subframe_offsets[MAX_SUBFRAMES]; ///< subframe positions in the current frame
61 uint8_t cur_subframe; ///< current subframe number
62 uint16_t decoded_samples; ///< number of already processed samples
63 int quant_step; ///< quantization step for the current subframe
64 int transient_counter; ///< number of transient samples from the beginning of the transient zone
68 * @brief main decoder context
70 typedef struct WmallDecodeCtx {
71 /* generic decoder variables */
72 AVCodecContext *avctx;
74 LLAudDSPContext dsp; ///< accelerated DSP functions
75 uint8_t frame_data[MAX_FRAMESIZE + FF_INPUT_BUFFER_PADDING_SIZE]; ///< compressed frame data
76 PutBitContext pb; ///< context for filling the frame_data buffer
78 /* frame size dependent frame information (set during initialization) */
79 uint32_t decode_flags; ///< used compression features
80 int len_prefix; ///< frame is prefixed with its length
81 int dynamic_range_compression; ///< frame contains DRC data
82 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
83 uint16_t samples_per_frame; ///< number of samples to output
84 uint16_t log2_frame_size;
85 int8_t num_channels; ///< number of channels in the stream (same as AVCodecContext.num_channels)
86 int8_t lfe_channel; ///< lfe channel index
87 uint8_t max_num_subframes;
88 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
89 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
90 uint16_t min_samples_per_subframe;
92 /* packet decode state */
93 GetBitContext pgb; ///< bitstream reader context for the packet
94 int next_packet_start; ///< start offset of the next WMA packet in the demuxer packet
95 uint8_t packet_offset; ///< offset to the frame in the packet
96 uint8_t packet_sequence_number; ///< current packet number
97 int num_saved_bits; ///< saved number of bits
98 int frame_offset; ///< frame offset in the bit reservoir
99 int subframe_offset; ///< subframe offset in the bit reservoir
100 uint8_t packet_loss; ///< set in case of bitstream error
101 uint8_t packet_done; ///< set when a packet is fully decoded
103 /* frame decode state */
104 uint32_t frame_num; ///< current frame number (not used for decoding)
105 GetBitContext gb; ///< bitstream reader context
106 int buf_bit_size; ///< buffer size in bits
107 int16_t *samples_16[WMALL_MAX_CHANNELS]; ///< current samplebuffer pointer (16-bit)
108 int32_t *samples_32[WMALL_MAX_CHANNELS]; ///< current samplebuffer pointer (24-bit)
109 uint8_t drc_gain; ///< gain for the DRC tool
110 int8_t skip_frame; ///< skip output step
111 int8_t parsed_all_subframes; ///< all subframes decoded?
113 /* subframe/block decode state */
114 int16_t subframe_len; ///< current subframe length
115 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
116 int8_t channel_indexes_for_cur_subframe[WMALL_MAX_CHANNELS];
118 WmallChannelCtx channel[WMALL_MAX_CHANNELS]; ///< per channel data
120 // WMA Lossless-specific
122 uint8_t do_arith_coding;
123 uint8_t do_ac_filter;
124 uint8_t do_inter_ch_decorr;
128 int8_t acfilter_order;
129 int8_t acfilter_scaling;
130 int64_t acfilter_coeffs[16];
131 int acfilter_prevvalues[WMALL_MAX_CHANNELS][16];
134 int8_t mclms_scaling;
135 int16_t mclms_coeffs[WMALL_MAX_CHANNELS * WMALL_MAX_CHANNELS * 32];
136 int16_t mclms_coeffs_cur[WMALL_MAX_CHANNELS * WMALL_MAX_CHANNELS];
137 int16_t mclms_prevvalues[WMALL_MAX_CHANNELS * 2 * 32];
138 int16_t mclms_updates[WMALL_MAX_CHANNELS * 2 * 32];
149 DECLARE_ALIGNED(16, int16_t, coefs)[MAX_ORDER + WMALL_COEFF_PAD_SIZE/sizeof(int16_t)];
150 DECLARE_ALIGNED(16, int16_t, lms_prevvalues)[MAX_ORDER * 2];
151 DECLARE_ALIGNED(16, int16_t, lms_updates)[MAX_ORDER * 2];
153 } cdlms[WMALL_MAX_CHANNELS][9];
155 int cdlms_ttl[WMALL_MAX_CHANNELS];
159 int is_channel_coded[WMALL_MAX_CHANNELS];
160 int update_speed[WMALL_MAX_CHANNELS];
162 int transient[WMALL_MAX_CHANNELS];
163 int transient_pos[WMALL_MAX_CHANNELS];
166 int ave_sum[WMALL_MAX_CHANNELS];
168 int channel_residues[WMALL_MAX_CHANNELS][WMALL_BLOCK_MAX_SIZE];
170 int lpc_coefs[WMALL_MAX_CHANNELS][40];
175 int channel_coeffs[WMALL_MAX_CHANNELS][WMALL_BLOCK_MAX_SIZE];
179 static av_cold int decode_init(AVCodecContext *avctx)
181 WmallDecodeCtx *s = avctx->priv_data;
182 uint8_t *edata_ptr = avctx->extradata;
183 unsigned int channel_mask;
184 int i, log2_max_num_subframes;
186 if (!avctx->block_align) {
187 av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
188 return AVERROR(EINVAL);
192 ff_llauddsp_init(&s->dsp);
193 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
195 if (avctx->extradata_size >= 18) {
196 s->decode_flags = AV_RL16(edata_ptr + 14);
197 channel_mask = AV_RL32(edata_ptr + 2);
198 s->bits_per_sample = AV_RL16(edata_ptr);
199 if (s->bits_per_sample == 16)
200 avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
201 else if (s->bits_per_sample == 24) {
202 avctx->sample_fmt = AV_SAMPLE_FMT_S32P;
203 avpriv_report_missing_feature(avctx, "Bit-depth higher than 16");
204 return AVERROR_PATCHWELCOME;
206 av_log(avctx, AV_LOG_ERROR, "Unknown bit-depth: %"PRIu8"\n",
208 return AVERROR_INVALIDDATA;
210 /* dump the extradata */
211 for (i = 0; i < avctx->extradata_size; i++)
212 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
213 av_dlog(avctx, "\n");
216 avpriv_request_sample(avctx, "Unsupported extradata size");
217 return AVERROR_PATCHWELCOME;
221 s->log2_frame_size = av_log2(avctx->block_align) + 4;
224 s->skip_frame = 1; /* skip first frame */
226 s->len_prefix = s->decode_flags & 0x40;
229 s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
231 av_assert0(s->samples_per_frame <= WMALL_BLOCK_MAX_SIZE);
233 /* init previous block len */
234 for (i = 0; i < avctx->channels; i++)
235 s->channel[i].prev_block_len = s->samples_per_frame;
238 log2_max_num_subframes = (s->decode_flags & 0x38) >> 3;
239 s->max_num_subframes = 1 << log2_max_num_subframes;
240 s->max_subframe_len_bit = 0;
241 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
243 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
244 s->dynamic_range_compression = s->decode_flags & 0x80;
245 s->bV3RTM = s->decode_flags & 0x100;
247 if (s->max_num_subframes > MAX_SUBFRAMES) {
248 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %"PRIu8"\n",
249 s->max_num_subframes);
250 return AVERROR_INVALIDDATA;
253 s->num_channels = avctx->channels;
255 /* extract lfe channel position */
258 if (channel_mask & 8) {
260 for (mask = 1; mask < 16; mask <<= 1)
261 if (channel_mask & mask)
265 if (s->num_channels < 0) {
266 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %"PRId8"\n",
268 return AVERROR_INVALIDDATA;
269 } else if (s->num_channels > WMALL_MAX_CHANNELS) {
270 avpriv_request_sample(avctx,
271 "More than %d channels", WMALL_MAX_CHANNELS);
272 return AVERROR_PATCHWELCOME;
275 s->frame = av_frame_alloc();
277 return AVERROR(ENOMEM);
279 avctx->channel_layout = channel_mask;
284 * @brief Decode the subframe length.
286 * @param offset sample offset in the frame
287 * @return decoded subframe length on success, < 0 in case of an error
289 static int decode_subframe_length(WmallDecodeCtx *s, int offset)
291 int frame_len_ratio, subframe_len, len;
293 /* no need to read from the bitstream when only one length is possible */
294 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
295 return s->min_samples_per_subframe;
297 len = av_log2(s->max_num_subframes - 1) + 1;
298 frame_len_ratio = get_bits(&s->gb, len);
299 subframe_len = s->min_samples_per_subframe * (frame_len_ratio + 1);
301 /* sanity check the length */
302 if (subframe_len < s->min_samples_per_subframe ||
303 subframe_len > s->samples_per_frame) {
304 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
306 return AVERROR_INVALIDDATA;
312 * @brief Decode how the data in the frame is split into subframes.
313 * Every WMA frame contains the encoded data for a fixed number of
314 * samples per channel. The data for every channel might be split
315 * into several subframes. This function will reconstruct the list of
316 * subframes for every channel.
318 * If the subframes are not evenly split, the algorithm estimates the
319 * channels with the lowest number of total samples.
320 * Afterwards, for each of these channels a bit is read from the
321 * bitstream that indicates if the channel contains a subframe with the
322 * next subframe size that is going to be read from the bitstream or not.
323 * If a channel contains such a subframe, the subframe size gets added to
324 * the channel's subframe list.
325 * The algorithm repeats these steps until the frame is properly divided
326 * between the individual channels.
329 * @return 0 on success, < 0 in case of an error
331 static int decode_tilehdr(WmallDecodeCtx *s)
333 uint16_t num_samples[WMALL_MAX_CHANNELS] = { 0 }; /* sum of samples for all currently known subframes of a channel */
334 uint8_t contains_subframe[WMALL_MAX_CHANNELS]; /* flag indicating if a channel contains the current subframe */
335 int channels_for_cur_subframe = s->num_channels; /* number of channels that contain the current subframe */
336 int fixed_channel_layout = 0; /* flag indicating that all channels use the same subfra2me offsets and sizes */
337 int min_channel_len = 0; /* smallest sum of samples (channels with this length will be processed first) */
340 /* reset tiling information */
341 for (c = 0; c < s->num_channels; c++)
342 s->channel[c].num_subframes = 0;
344 tile_aligned = get_bits1(&s->gb);
345 if (s->max_num_subframes == 1 || tile_aligned)
346 fixed_channel_layout = 1;
348 /* loop until the frame data is split between the subframes */
350 int subframe_len, in_use = 0;
352 /* check which channels contain the subframe */
353 for (c = 0; c < s->num_channels; c++) {
354 if (num_samples[c] == min_channel_len) {
355 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
356 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe)) {
357 contains_subframe[c] = 1;
359 contains_subframe[c] = get_bits1(&s->gb);
361 in_use |= contains_subframe[c];
363 contains_subframe[c] = 0;
367 av_log(s->avctx, AV_LOG_ERROR,
368 "Found empty subframe\n");
369 return AVERROR_INVALIDDATA;
372 /* get subframe length, subframe_len == 0 is not allowed */
373 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
374 return AVERROR_INVALIDDATA;
375 /* add subframes to the individual channels and find new min_channel_len */
376 min_channel_len += subframe_len;
377 for (c = 0; c < s->num_channels; c++) {
378 WmallChannelCtx *chan = &s->channel[c];
380 if (contains_subframe[c]) {
381 if (chan->num_subframes >= MAX_SUBFRAMES) {
382 av_log(s->avctx, AV_LOG_ERROR,
383 "broken frame: num subframes > 31\n");
384 return AVERROR_INVALIDDATA;
386 chan->subframe_len[chan->num_subframes] = subframe_len;
387 num_samples[c] += subframe_len;
388 ++chan->num_subframes;
389 if (num_samples[c] > s->samples_per_frame) {
390 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
391 "channel len(%"PRIu16") > samples_per_frame(%"PRIu16")\n",
392 num_samples[c], s->samples_per_frame);
393 return AVERROR_INVALIDDATA;
395 } else if (num_samples[c] <= min_channel_len) {
396 if (num_samples[c] < min_channel_len) {
397 channels_for_cur_subframe = 0;
398 min_channel_len = num_samples[c];
400 ++channels_for_cur_subframe;
403 } while (min_channel_len < s->samples_per_frame);
405 for (c = 0; c < s->num_channels; c++) {
407 for (i = 0; i < s->channel[c].num_subframes; i++) {
408 s->channel[c].subframe_offsets[i] = offset;
409 offset += s->channel[c].subframe_len[i];
416 static void decode_ac_filter(WmallDecodeCtx *s)
419 s->acfilter_order = get_bits(&s->gb, 4) + 1;
420 s->acfilter_scaling = get_bits(&s->gb, 4);
422 for (i = 0; i < s->acfilter_order; i++)
423 s->acfilter_coeffs[i] = (s->acfilter_scaling ?
424 get_bits(&s->gb, s->acfilter_scaling) : 0) + 1;
427 static void decode_mclms(WmallDecodeCtx *s)
429 s->mclms_order = (get_bits(&s->gb, 4) + 1) * 2;
430 s->mclms_scaling = get_bits(&s->gb, 4);
431 if (get_bits1(&s->gb)) {
432 int i, send_coef_bits;
433 int cbits = av_log2(s->mclms_scaling + 1);
434 if (1 << cbits < s->mclms_scaling + 1)
437 send_coef_bits = (cbits ? get_bits(&s->gb, cbits) : 0) + 2;
439 for (i = 0; i < s->mclms_order * s->num_channels * s->num_channels; i++)
440 s->mclms_coeffs[i] = get_bits(&s->gb, send_coef_bits);
442 for (i = 0; i < s->num_channels; i++) {
444 for (c = 0; c < i; c++)
445 s->mclms_coeffs_cur[i * s->num_channels + c] = get_bits(&s->gb, send_coef_bits);
450 static int decode_cdlms(WmallDecodeCtx *s)
453 int cdlms_send_coef = get_bits1(&s->gb);
455 for (c = 0; c < s->num_channels; c++) {
456 s->cdlms_ttl[c] = get_bits(&s->gb, 3) + 1;
457 for (i = 0; i < s->cdlms_ttl[c]; i++) {
458 s->cdlms[c][i].order = (get_bits(&s->gb, 7) + 1) * 8;
459 if (s->cdlms[c][i].order > MAX_ORDER) {
460 av_log(s->avctx, AV_LOG_ERROR,
461 "Order[%d][%d] %d > max (%d), not supported\n",
462 c, i, s->cdlms[c][i].order, MAX_ORDER);
463 s->cdlms[0][0].order = 0;
464 return AVERROR_INVALIDDATA;
466 if(s->cdlms[c][i].order & 8) {
469 avpriv_request_sample(s->avctx, "CDLMS of order %d",
470 s->cdlms[c][i].order);
475 for (i = 0; i < s->cdlms_ttl[c]; i++)
476 s->cdlms[c][i].scaling = get_bits(&s->gb, 4);
478 if (cdlms_send_coef) {
479 for (i = 0; i < s->cdlms_ttl[c]; i++) {
480 int cbits, shift_l, shift_r, j;
481 cbits = av_log2(s->cdlms[c][i].order);
482 if ((1 << cbits) < s->cdlms[c][i].order)
484 s->cdlms[c][i].coefsend = get_bits(&s->gb, cbits) + 1;
486 cbits = av_log2(s->cdlms[c][i].scaling + 1);
487 if ((1 << cbits) < s->cdlms[c][i].scaling + 1)
490 s->cdlms[c][i].bitsend = get_bits(&s->gb, cbits) + 2;
491 shift_l = 32 - s->cdlms[c][i].bitsend;
492 shift_r = 32 - s->cdlms[c][i].scaling - 2;
493 for (j = 0; j < s->cdlms[c][i].coefsend; j++)
494 s->cdlms[c][i].coefs[j] =
495 (get_bits(&s->gb, s->cdlms[c][i].bitsend) << shift_l) >> shift_r;
499 for (i = 0; i < s->cdlms_ttl[c]; i++)
500 memset(s->cdlms[c][i].coefs + s->cdlms[c][i].order,
501 0, WMALL_COEFF_PAD_SIZE);
507 static int decode_channel_residues(WmallDecodeCtx *s, int ch, int tile_size)
510 unsigned int ave_mean;
511 s->transient[ch] = get_bits1(&s->gb);
512 if (s->transient[ch]) {
513 s->transient_pos[ch] = get_bits(&s->gb, av_log2(tile_size));
514 if (s->transient_pos[ch])
515 s->transient[ch] = 0;
516 s->channel[ch].transient_counter =
517 FFMAX(s->channel[ch].transient_counter, s->samples_per_frame / 2);
518 } else if (s->channel[ch].transient_counter)
519 s->transient[ch] = 1;
521 if (s->seekable_tile) {
522 ave_mean = get_bits(&s->gb, s->bits_per_sample);
523 s->ave_sum[ch] = ave_mean << (s->movave_scaling + 1);
526 if (s->seekable_tile) {
527 if (s->do_inter_ch_decorr)
528 s->channel_residues[ch][0] = get_sbits_long(&s->gb, s->bits_per_sample + 1);
530 s->channel_residues[ch][0] = get_sbits_long(&s->gb, s->bits_per_sample);
533 for (; i < tile_size; i++) {
534 int quo = 0, rem, rem_bits, residue;
535 while(get_bits1(&s->gb)) {
537 if (get_bits_left(&s->gb) <= 0)
541 quo += get_bits_long(&s->gb, get_bits(&s->gb, 5) + 1);
543 ave_mean = (s->ave_sum[ch] + (1 << s->movave_scaling)) >> (s->movave_scaling + 1);
547 rem_bits = av_ceil_log2(ave_mean);
548 rem = get_bits_long(&s->gb, rem_bits);
549 residue = (quo << rem_bits) + rem;
552 s->ave_sum[ch] = residue + s->ave_sum[ch] -
553 (s->ave_sum[ch] >> s->movave_scaling);
556 residue = -(residue >> 1) - 1;
558 residue = residue >> 1;
559 s->channel_residues[ch][i] = residue;
566 static void decode_lpc(WmallDecodeCtx *s)
569 s->lpc_order = get_bits(&s->gb, 5) + 1;
570 s->lpc_scaling = get_bits(&s->gb, 4);
571 s->lpc_intbits = get_bits(&s->gb, 3) + 1;
572 cbits = s->lpc_scaling + s->lpc_intbits;
573 for (ch = 0; ch < s->num_channels; ch++)
574 for (i = 0; i < s->lpc_order; i++)
575 s->lpc_coefs[ch][i] = get_sbits(&s->gb, cbits);
578 static void clear_codec_buffers(WmallDecodeCtx *s)
582 memset(s->acfilter_coeffs, 0, sizeof(s->acfilter_coeffs));
583 memset(s->acfilter_prevvalues, 0, sizeof(s->acfilter_prevvalues));
584 memset(s->lpc_coefs, 0, sizeof(s->lpc_coefs));
586 memset(s->mclms_coeffs, 0, sizeof(s->mclms_coeffs));
587 memset(s->mclms_coeffs_cur, 0, sizeof(s->mclms_coeffs_cur));
588 memset(s->mclms_prevvalues, 0, sizeof(s->mclms_prevvalues));
589 memset(s->mclms_updates, 0, sizeof(s->mclms_updates));
591 for (ich = 0; ich < s->num_channels; ich++) {
592 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++) {
593 memset(s->cdlms[ich][ilms].coefs, 0,
594 sizeof(s->cdlms[ich][ilms].coefs));
595 memset(s->cdlms[ich][ilms].lms_prevvalues, 0,
596 sizeof(s->cdlms[ich][ilms].lms_prevvalues));
597 memset(s->cdlms[ich][ilms].lms_updates, 0,
598 sizeof(s->cdlms[ich][ilms].lms_updates));
605 * @brief Reset filter parameters and transient area at new seekable tile.
607 static void reset_codec(WmallDecodeCtx *s)
610 s->mclms_recent = s->mclms_order * s->num_channels;
611 for (ich = 0; ich < s->num_channels; ich++) {
612 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++)
613 s->cdlms[ich][ilms].recent = s->cdlms[ich][ilms].order;
614 /* first sample of a seekable subframe is considered as the starting of
615 a transient area which is samples_per_frame samples long */
616 s->channel[ich].transient_counter = s->samples_per_frame;
617 s->transient[ich] = 1;
618 s->transient_pos[ich] = 0;
622 static void mclms_update(WmallDecodeCtx *s, int icoef, int *pred)
624 int i, j, ich, pred_error;
625 int order = s->mclms_order;
626 int num_channels = s->num_channels;
627 int range = 1 << (s->bits_per_sample - 1);
629 for (ich = 0; ich < num_channels; ich++) {
630 pred_error = s->channel_residues[ich][icoef] - pred[ich];
631 if (pred_error > 0) {
632 for (i = 0; i < order * num_channels; i++)
633 s->mclms_coeffs[i + ich * order * num_channels] +=
634 s->mclms_updates[s->mclms_recent + i];
635 for (j = 0; j < ich; j++) {
636 if (s->channel_residues[j][icoef] > 0)
637 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
638 else if (s->channel_residues[j][icoef] < 0)
639 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
641 } else if (pred_error < 0) {
642 for (i = 0; i < order * num_channels; i++)
643 s->mclms_coeffs[i + ich * order * num_channels] -=
644 s->mclms_updates[s->mclms_recent + i];
645 for (j = 0; j < ich; j++) {
646 if (s->channel_residues[j][icoef] > 0)
647 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
648 else if (s->channel_residues[j][icoef] < 0)
649 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
654 for (ich = num_channels - 1; ich >= 0; ich--) {
656 s->mclms_prevvalues[s->mclms_recent] = s->channel_residues[ich][icoef];
657 if (s->channel_residues[ich][icoef] > range - 1)
658 s->mclms_prevvalues[s->mclms_recent] = range - 1;
659 else if (s->channel_residues[ich][icoef] < -range)
660 s->mclms_prevvalues[s->mclms_recent] = -range;
662 s->mclms_updates[s->mclms_recent] = 0;
663 if (s->channel_residues[ich][icoef] > 0)
664 s->mclms_updates[s->mclms_recent] = 1;
665 else if (s->channel_residues[ich][icoef] < 0)
666 s->mclms_updates[s->mclms_recent] = -1;
669 if (s->mclms_recent == 0) {
670 memcpy(&s->mclms_prevvalues[order * num_channels],
672 sizeof(int16_t) * order * num_channels);
673 memcpy(&s->mclms_updates[order * num_channels],
675 sizeof(int16_t) * order * num_channels);
676 s->mclms_recent = num_channels * order;
680 static void mclms_predict(WmallDecodeCtx *s, int icoef, int *pred)
683 int order = s->mclms_order;
684 int num_channels = s->num_channels;
686 for (ich = 0; ich < num_channels; ich++) {
688 if (!s->is_channel_coded[ich])
690 for (i = 0; i < order * num_channels; i++)
691 pred[ich] += s->mclms_prevvalues[i + s->mclms_recent] *
692 s->mclms_coeffs[i + order * num_channels * ich];
693 for (i = 0; i < ich; i++)
694 pred[ich] += s->channel_residues[i][icoef] *
695 s->mclms_coeffs_cur[i + num_channels * ich];
696 pred[ich] += 1 << s->mclms_scaling - 1;
697 pred[ich] >>= s->mclms_scaling;
698 s->channel_residues[ich][icoef] += pred[ich];
702 static void revert_mclms(WmallDecodeCtx *s, int tile_size)
704 int icoef, pred[WMALL_MAX_CHANNELS] = { 0 };
705 for (icoef = 0; icoef < tile_size; icoef++) {
706 mclms_predict(s, icoef, pred);
707 mclms_update(s, icoef, pred);
711 static void lms_update(WmallDecodeCtx *s, int ich, int ilms, int input)
713 int recent = s->cdlms[ich][ilms].recent;
714 int range = 1 << s->bits_per_sample - 1;
719 memcpy(&s->cdlms[ich][ilms].lms_prevvalues[s->cdlms[ich][ilms].order],
720 s->cdlms[ich][ilms].lms_prevvalues,
721 2 * s->cdlms[ich][ilms].order);
722 memcpy(&s->cdlms[ich][ilms].lms_updates[s->cdlms[ich][ilms].order],
723 s->cdlms[ich][ilms].lms_updates,
724 2 * s->cdlms[ich][ilms].order);
725 recent = s->cdlms[ich][ilms].order - 1;
728 s->cdlms[ich][ilms].lms_prevvalues[recent] = av_clip(input, -range, range - 1);
730 s->cdlms[ich][ilms].lms_updates[recent] = 0;
732 s->cdlms[ich][ilms].lms_updates[recent] = -s->update_speed[ich];
734 s->cdlms[ich][ilms].lms_updates[recent] = s->update_speed[ich];
736 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 4)] >>= 2;
737 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 3)] >>= 1;
738 s->cdlms[ich][ilms].recent = recent;
741 static void use_high_update_speed(WmallDecodeCtx *s, int ich)
743 int ilms, recent, icoef;
744 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
745 recent = s->cdlms[ich][ilms].recent;
746 if (s->update_speed[ich] == 16)
749 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
750 s->cdlms[ich][ilms].lms_updates[icoef + recent] *= 2;
752 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
753 s->cdlms[ich][ilms].lms_updates[icoef] *= 2;
756 s->update_speed[ich] = 16;
759 static void use_normal_update_speed(WmallDecodeCtx *s, int ich)
761 int ilms, recent, icoef;
762 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
763 recent = s->cdlms[ich][ilms].recent;
764 if (s->update_speed[ich] == 8)
767 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
768 s->cdlms[ich][ilms].lms_updates[icoef + recent] /= 2;
770 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
771 s->cdlms[ich][ilms].lms_updates[icoef] /= 2;
773 s->update_speed[ich] = 8;
776 /** Get sign of integer (1 for positive, -1 for negative and 0 for zero) */
777 #define WMASIGN(x) ((x > 0) - (x < 0))
779 static void revert_cdlms(WmallDecodeCtx *s, int ch,
780 int coef_begin, int coef_end)
782 int icoef, pred, ilms, num_lms, residue, input;
784 num_lms = s->cdlms_ttl[ch];
785 for (ilms = num_lms - 1; ilms >= 0; ilms--) {
786 for (icoef = coef_begin; icoef < coef_end; icoef++) {
787 pred = 1 << (s->cdlms[ch][ilms].scaling - 1);
788 residue = s->channel_residues[ch][icoef];
789 pred += s->dsp.scalarproduct_and_madd_int16(s->cdlms[ch][ilms].coefs,
790 s->cdlms[ch][ilms].lms_prevvalues
791 + s->cdlms[ch][ilms].recent,
792 s->cdlms[ch][ilms].lms_updates
793 + s->cdlms[ch][ilms].recent,
794 s->cdlms[ch][ilms].order,
796 input = residue + (pred >> s->cdlms[ch][ilms].scaling);
797 lms_update(s, ch, ilms, input);
798 s->channel_residues[ch][icoef] = input;
804 static void revert_inter_ch_decorr(WmallDecodeCtx *s, int tile_size)
806 if (s->num_channels != 2)
808 else if (s->is_channel_coded[0] || s->is_channel_coded[1]) {
810 for (icoef = 0; icoef < tile_size; icoef++) {
811 s->channel_residues[0][icoef] -= s->channel_residues[1][icoef] >> 1;
812 s->channel_residues[1][icoef] += s->channel_residues[0][icoef];
817 static void revert_acfilter(WmallDecodeCtx *s, int tile_size)
820 int64_t *filter_coeffs = s->acfilter_coeffs;
821 int scaling = s->acfilter_scaling;
822 int order = s->acfilter_order;
824 for (ich = 0; ich < s->num_channels; ich++) {
825 int *prevvalues = s->acfilter_prevvalues[ich];
826 for (i = 0; i < order; i++) {
828 for (j = 0; j < order; j++) {
830 pred += filter_coeffs[j] * prevvalues[j - i];
832 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
835 s->channel_residues[ich][i] += pred;
837 for (i = order; i < tile_size; i++) {
839 for (j = 0; j < order; j++)
840 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
842 s->channel_residues[ich][i] += pred;
844 for (j = 0; j < order; j++)
845 prevvalues[j] = s->channel_residues[ich][tile_size - j - 1];
849 static int decode_subframe(WmallDecodeCtx *s)
851 int offset = s->samples_per_frame;
852 int subframe_len = s->samples_per_frame;
853 int total_samples = s->samples_per_frame * s->num_channels;
854 int i, j, rawpcm_tile, padding_zeroes, res;
856 s->subframe_offset = get_bits_count(&s->gb);
858 /* reset channel context and find the next block offset and size
859 == the next block of the channel with the smallest number of
861 for (i = 0; i < s->num_channels; i++) {
862 if (offset > s->channel[i].decoded_samples) {
863 offset = s->channel[i].decoded_samples;
865 s->channel[i].subframe_len[s->channel[i].cur_subframe];
869 /* get a list of all channels that contain the estimated block */
870 s->channels_for_cur_subframe = 0;
871 for (i = 0; i < s->num_channels; i++) {
872 const int cur_subframe = s->channel[i].cur_subframe;
873 /* subtract already processed samples */
874 total_samples -= s->channel[i].decoded_samples;
876 /* and count if there are multiple subframes that match our profile */
877 if (offset == s->channel[i].decoded_samples &&
878 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
879 total_samples -= s->channel[i].subframe_len[cur_subframe];
880 s->channel[i].decoded_samples +=
881 s->channel[i].subframe_len[cur_subframe];
882 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
883 ++s->channels_for_cur_subframe;
887 /* check if the frame will be complete after processing the
890 s->parsed_all_subframes = 1;
893 s->seekable_tile = get_bits1(&s->gb);
894 if (s->seekable_tile) {
895 clear_codec_buffers(s);
897 s->do_arith_coding = get_bits1(&s->gb);
898 if (s->do_arith_coding) {
899 avpriv_request_sample(s->avctx, "Arithmetic coding");
900 return AVERROR_PATCHWELCOME;
902 s->do_ac_filter = get_bits1(&s->gb);
903 s->do_inter_ch_decorr = get_bits1(&s->gb);
904 s->do_mclms = get_bits1(&s->gb);
912 if ((res = decode_cdlms(s)) < 0)
914 s->movave_scaling = get_bits(&s->gb, 3);
915 s->quant_stepsize = get_bits(&s->gb, 8) + 1;
918 } else if (!s->cdlms[0][0].order) {
919 av_log(s->avctx, AV_LOG_DEBUG,
920 "Waiting for seekable tile\n");
921 av_frame_unref(s->frame);
925 rawpcm_tile = get_bits1(&s->gb);
927 for (i = 0; i < s->num_channels; i++)
928 s->is_channel_coded[i] = 1;
931 for (i = 0; i < s->num_channels; i++)
932 s->is_channel_coded[i] = get_bits1(&s->gb);
936 s->do_lpc = get_bits1(&s->gb);
939 avpriv_request_sample(s->avctx, "Expect wrong output since "
940 "inverse LPC filter");
947 if (get_bits1(&s->gb))
948 padding_zeroes = get_bits(&s->gb, 5);
953 int bits = s->bits_per_sample - padding_zeroes;
955 av_log(s->avctx, AV_LOG_ERROR,
956 "Invalid number of padding bits in raw PCM tile\n");
957 return AVERROR_INVALIDDATA;
959 av_dlog(s->avctx, "RAWPCM %d bits per sample. "
960 "total %d bits, remain=%d\n", bits,
961 bits * s->num_channels * subframe_len, get_bits_count(&s->gb));
962 for (i = 0; i < s->num_channels; i++)
963 for (j = 0; j < subframe_len; j++)
964 s->channel_coeffs[i][j] = get_sbits_long(&s->gb, bits);
966 for (i = 0; i < s->num_channels; i++)
967 if (s->is_channel_coded[i]) {
968 decode_channel_residues(s, i, subframe_len);
969 if (s->seekable_tile)
970 use_high_update_speed(s, i);
972 use_normal_update_speed(s, i);
973 revert_cdlms(s, i, 0, subframe_len);
975 memset(s->channel_residues[i], 0, sizeof(**s->channel_residues) * subframe_len);
979 revert_mclms(s, subframe_len);
980 if (s->do_inter_ch_decorr)
981 revert_inter_ch_decorr(s, subframe_len);
983 revert_acfilter(s, subframe_len);
986 if (s->quant_stepsize != 1)
987 for (i = 0; i < s->num_channels; i++)
988 for (j = 0; j < subframe_len; j++)
989 s->channel_residues[i][j] *= s->quant_stepsize;
991 /* Write to proper output buffer depending on bit-depth */
992 for (i = 0; i < s->channels_for_cur_subframe; i++) {
993 int c = s->channel_indexes_for_cur_subframe[i];
994 int subframe_len = s->channel[c].subframe_len[s->channel[c].cur_subframe];
996 for (j = 0; j < subframe_len; j++) {
997 if (s->bits_per_sample == 16) {
998 *s->samples_16[c]++ = (int16_t) s->channel_residues[c][j] << padding_zeroes;
1000 *s->samples_32[c]++ = s->channel_residues[c][j] << padding_zeroes;
1005 /* handled one subframe */
1006 for (i = 0; i < s->channels_for_cur_subframe; i++) {
1007 int c = s->channel_indexes_for_cur_subframe[i];
1008 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
1009 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
1010 return AVERROR_INVALIDDATA;
1012 ++s->channel[c].cur_subframe;
1018 * @brief Decode one WMA frame.
1019 * @param s codec context
1020 * @return 0 if the trailer bit indicates that this is the last frame,
1021 * 1 if there are additional frames
1023 static int decode_frame(WmallDecodeCtx *s)
1025 GetBitContext* gb = &s->gb;
1026 int more_frames = 0, len = 0, i, ret;
1028 s->frame->nb_samples = s->samples_per_frame;
1029 if ((ret = ff_get_buffer(s->avctx, s->frame, 0)) < 0) {
1030 /* return an error if no frame could be decoded at all */
1034 for (i = 0; i < s->num_channels; i++) {
1035 s->samples_16[i] = (int16_t *)s->frame->extended_data[i];
1036 s->samples_32[i] = (int32_t *)s->frame->extended_data[i];
1039 /* get frame length */
1041 len = get_bits(gb, s->log2_frame_size);
1043 /* decode tile information */
1044 if ((ret = decode_tilehdr(s))) {
1046 av_frame_unref(s->frame);
1051 if (s->dynamic_range_compression)
1052 s->drc_gain = get_bits(gb, 8);
1054 /* no idea what these are for, might be the number of samples
1055 that need to be skipped at the beginning or end of a stream */
1056 if (get_bits1(gb)) {
1059 /* usually true for the first frame */
1060 if (get_bits1(gb)) {
1061 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1062 av_dlog(s->avctx, "start skip: %i\n", skip);
1065 /* sometimes true for the last frame */
1066 if (get_bits1(gb)) {
1067 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1068 av_dlog(s->avctx, "end skip: %i\n", skip);
1073 /* reset subframe states */
1074 s->parsed_all_subframes = 0;
1075 for (i = 0; i < s->num_channels; i++) {
1076 s->channel[i].decoded_samples = 0;
1077 s->channel[i].cur_subframe = 0;
1080 /* decode all subframes */
1081 while (!s->parsed_all_subframes) {
1082 int decoded_samples = s->channel[0].decoded_samples;
1083 if (decode_subframe(s) < 0) {
1085 if (s->frame->nb_samples)
1086 s->frame->nb_samples = decoded_samples;
1091 av_dlog(s->avctx, "Frame done\n");
1096 if (s->len_prefix) {
1097 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1098 /* FIXME: not sure if this is always an error */
1099 av_log(s->avctx, AV_LOG_ERROR,
1100 "frame[%"PRIu32"] would have to skip %i bits\n",
1102 len - (get_bits_count(gb) - s->frame_offset) - 1);
1107 /* skip the rest of the frame data */
1108 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1111 /* decode trailer bit */
1112 more_frames = get_bits1(gb);
1118 * @brief Calculate remaining input buffer length.
1119 * @param s codec context
1120 * @param gb bitstream reader context
1121 * @return remaining size in bits
1123 static int remaining_bits(WmallDecodeCtx *s, GetBitContext *gb)
1125 return s->buf_bit_size - get_bits_count(gb);
1129 * @brief Fill the bit reservoir with a (partial) frame.
1130 * @param s codec context
1131 * @param gb bitstream reader context
1132 * @param len length of the partial frame
1133 * @param append decides whether to reset the buffer or not
1135 static void save_bits(WmallDecodeCtx *s, GetBitContext* gb, int len,
1141 /* when the frame data does not need to be concatenated, the input buffer
1142 is reset and additional bits from the previous frame are copied
1143 and skipped later so that a fast byte copy is possible */
1146 s->frame_offset = get_bits_count(gb) & 7;
1147 s->num_saved_bits = s->frame_offset;
1148 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1151 buflen = (s->num_saved_bits + len + 8) >> 3;
1153 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1154 avpriv_request_sample(s->avctx, "Too small input buffer");
1159 s->num_saved_bits += len;
1161 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1164 int align = 8 - (get_bits_count(gb) & 7);
1165 align = FFMIN(align, len);
1166 put_bits(&s->pb, align, get_bits(gb, align));
1168 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1170 skip_bits_long(gb, len);
1173 flush_put_bits(&tmp);
1175 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1176 skip_bits(&s->gb, s->frame_offset);
1179 static int decode_packet(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1182 WmallDecodeCtx *s = avctx->priv_data;
1183 GetBitContext* gb = &s->pgb;
1184 const uint8_t* buf = avpkt->data;
1185 int buf_size = avpkt->size;
1186 int num_bits_prev_frame, packet_sequence_number, spliced_packet;
1188 s->frame->nb_samples = 0;
1190 if (s->packet_done || s->packet_loss) {
1195 /* sanity check for the buffer length */
1196 if (buf_size < avctx->block_align) {
1197 av_log(avctx, AV_LOG_ERROR, "buf size %d invalid\n", buf_size);
1198 return AVERROR_INVALIDDATA;
1201 s->next_packet_start = buf_size - avctx->block_align;
1202 buf_size = avctx->block_align;
1203 s->buf_bit_size = buf_size << 3;
1205 /* parse packet header */
1206 init_get_bits(gb, buf, s->buf_bit_size);
1207 packet_sequence_number = get_bits(gb, 4);
1208 skip_bits(gb, 1); // Skip seekable_frame_in_packet, currently ununused
1209 spliced_packet = get_bits1(gb);
1211 avpriv_request_sample(avctx, "Bitstream splicing");
1213 /* get number of bits that need to be added to the previous frame */
1214 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1216 /* check for packet loss */
1217 if (!s->packet_loss &&
1218 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1220 av_log(avctx, AV_LOG_ERROR,
1221 "Packet loss detected! seq %"PRIx8" vs %x\n",
1222 s->packet_sequence_number, packet_sequence_number);
1224 s->packet_sequence_number = packet_sequence_number;
1226 if (num_bits_prev_frame > 0) {
1227 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1228 if (num_bits_prev_frame >= remaining_packet_bits) {
1229 num_bits_prev_frame = remaining_packet_bits;
1233 /* Append the previous frame data to the remaining data from the
1234 * previous packet to create a full frame. */
1235 save_bits(s, gb, num_bits_prev_frame, 1);
1237 /* decode the cross packet frame if it is valid */
1238 if (num_bits_prev_frame < remaining_packet_bits && !s->packet_loss)
1240 } else if (s->num_saved_bits - s->frame_offset) {
1241 av_dlog(avctx, "ignoring %x previously saved bits\n",
1242 s->num_saved_bits - s->frame_offset);
1245 if (s->packet_loss) {
1246 /* Reset number of saved bits so that the decoder does not start
1247 * to decode incomplete frames in the s->len_prefix == 0 case. */
1248 s->num_saved_bits = 0;
1250 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1256 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1257 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1258 skip_bits(gb, s->packet_offset);
1260 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1261 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1262 frame_size <= remaining_bits(s, gb)) {
1263 save_bits(s, gb, frame_size, 0);
1264 s->packet_done = !decode_frame(s);
1265 } else if (!s->len_prefix
1266 && s->num_saved_bits > get_bits_count(&s->gb)) {
1267 /* when the frames do not have a length prefix, we don't know the
1268 * compressed length of the individual frames however, we know what
1269 * part of a new packet belongs to the previous frame therefore we
1270 * save the incoming packet first, then we append the "previous
1271 * frame" data from the next packet so that we get a buffer that
1272 * only contains full frames */
1273 s->packet_done = !decode_frame(s);
1279 if (s->packet_done && !s->packet_loss &&
1280 remaining_bits(s, gb) > 0) {
1281 /* save the rest of the data so that it can be decoded
1282 * with the next packet */
1283 save_bits(s, gb, remaining_bits(s, gb), 0);
1286 *got_frame_ptr = s->frame->nb_samples > 0;
1287 av_frame_move_ref(data, s->frame);
1289 s->packet_offset = get_bits_count(gb) & 7;
1291 return (s->packet_loss) ? AVERROR_INVALIDDATA : get_bits_count(gb) >> 3;
1294 static void flush(AVCodecContext *avctx)
1296 WmallDecodeCtx *s = avctx->priv_data;
1299 s->num_saved_bits = 0;
1300 s->frame_offset = 0;
1301 s->next_packet_start = 0;
1302 s->cdlms[0][0].order = 0;
1303 s->frame->nb_samples = 0;
1304 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1307 static av_cold int decode_close(AVCodecContext *avctx)
1309 WmallDecodeCtx *s = avctx->priv_data;
1311 av_frame_free(&s->frame);
1316 AVCodec ff_wmalossless_decoder = {
1317 .name = "wmalossless",
1318 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio Lossless"),
1319 .type = AVMEDIA_TYPE_AUDIO,
1320 .id = AV_CODEC_ID_WMALOSSLESS,
1321 .priv_data_size = sizeof(WmallDecodeCtx),
1322 .init = decode_init,
1323 .close = decode_close,
1324 .decode = decode_packet,
1326 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1 | CODEC_CAP_DELAY,
1327 .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
1329 AV_SAMPLE_FMT_NONE },