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
30 #include "wma_common.h"
32 /** current decoder limitations */
33 #define WMALL_MAX_CHANNELS 8 ///< max number of handled channels
34 #define MAX_SUBFRAMES 32 ///< max number of subframes per channel
35 #define MAX_BANDS 29 ///< max number of scale factor bands
36 #define MAX_FRAMESIZE 32768 ///< maximum compressed frame size
39 #define WMALL_BLOCK_MIN_BITS 6 ///< log2 of min block size
40 #define WMALL_BLOCK_MAX_BITS 12 ///< log2 of max block size
41 #define WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS) ///< maximum block size
42 #define WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1) ///< possible block sizes
46 * @brief frame-specific decoder context for a single channel
49 int16_t prev_block_len; ///< length of the previous block
50 uint8_t transmit_coefs;
51 uint8_t num_subframes;
52 uint16_t subframe_len[MAX_SUBFRAMES]; ///< subframe length in samples
53 uint16_t subframe_offsets[MAX_SUBFRAMES]; ///< subframe positions in the current frame
54 uint8_t cur_subframe; ///< current subframe number
55 uint16_t decoded_samples; ///< number of already processed samples
56 int quant_step; ///< quantization step for the current subframe
57 int transient_counter; ///< number of transient samples from the beginning of the transient zone
61 * @brief main decoder context
63 typedef struct WmallDecodeCtx {
64 /* generic decoder variables */
65 AVCodecContext *avctx;
67 uint8_t frame_data[MAX_FRAMESIZE + FF_INPUT_BUFFER_PADDING_SIZE]; ///< compressed frame data
68 PutBitContext pb; ///< context for filling the frame_data buffer
70 /* frame size dependent frame information (set during initialization) */
71 uint32_t decode_flags; ///< used compression features
72 int len_prefix; ///< frame is prefixed with its length
73 int dynamic_range_compression; ///< frame contains DRC data
74 uint8_t bits_per_sample; ///< integer audio sample size for the unscaled IMDCT output (used to scale to [-1.0, 1.0])
75 uint16_t samples_per_frame; ///< number of samples to output
76 uint16_t log2_frame_size;
77 int8_t num_channels; ///< number of channels in the stream (same as AVCodecContext.num_channels)
78 int8_t lfe_channel; ///< lfe channel index
79 uint8_t max_num_subframes;
80 uint8_t subframe_len_bits; ///< number of bits used for the subframe length
81 uint8_t max_subframe_len_bit; ///< flag indicating that the subframe is of maximum size when the first subframe length bit is 1
82 uint16_t min_samples_per_subframe;
84 /* packet decode state */
85 GetBitContext pgb; ///< bitstream reader context for the packet
86 int next_packet_start; ///< start offset of the next WMA packet in the demuxer packet
87 uint8_t packet_offset; ///< offset to the frame in the packet
88 uint8_t packet_sequence_number; ///< current packet number
89 int num_saved_bits; ///< saved number of bits
90 int frame_offset; ///< frame offset in the bit reservoir
91 int subframe_offset; ///< subframe offset in the bit reservoir
92 uint8_t packet_loss; ///< set in case of bitstream error
93 uint8_t packet_done; ///< set when a packet is fully decoded
95 /* frame decode state */
96 uint32_t frame_num; ///< current frame number (not used for decoding)
97 GetBitContext gb; ///< bitstream reader context
98 int buf_bit_size; ///< buffer size in bits
99 int16_t *samples_16[WMALL_MAX_CHANNELS]; ///< current samplebuffer pointer (16-bit)
100 int32_t *samples_32[WMALL_MAX_CHANNELS]; ///< current samplebuffer pointer (24-bit)
101 uint8_t drc_gain; ///< gain for the DRC tool
102 int8_t skip_frame; ///< skip output step
103 int8_t parsed_all_subframes; ///< all subframes decoded?
105 /* subframe/block decode state */
106 int16_t subframe_len; ///< current subframe length
107 int8_t channels_for_cur_subframe; ///< number of channels that contain the subframe
108 int8_t channel_indexes_for_cur_subframe[WMALL_MAX_CHANNELS];
110 WmallChannelCtx channel[WMALL_MAX_CHANNELS]; ///< per channel data
112 // WMA Lossless-specific
114 uint8_t do_arith_coding;
115 uint8_t do_ac_filter;
116 uint8_t do_inter_ch_decorr;
120 int8_t acfilter_order;
121 int8_t acfilter_scaling;
122 int64_t acfilter_coeffs[16];
123 int acfilter_prevvalues[2][16];
126 int8_t mclms_scaling;
127 int16_t mclms_coeffs[128];
128 int16_t mclms_coeffs_cur[4];
129 int16_t mclms_prevvalues[64];
130 int16_t mclms_updates[64];
141 int16_t coefs[MAX_ORDER];
142 int16_t lms_prevvalues[MAX_ORDER * 2];
143 int16_t lms_updates[MAX_ORDER * 2];
151 int is_channel_coded[2];
155 int transient_pos[2];
160 int channel_residues[2][2048];
162 int lpc_coefs[2][40];
167 int channel_coeffs[2][2048];
171 static av_cold int decode_init(AVCodecContext *avctx)
173 WmallDecodeCtx *s = avctx->priv_data;
174 uint8_t *edata_ptr = avctx->extradata;
175 unsigned int channel_mask;
176 int i, log2_max_num_subframes, num_possible_block_sizes;
179 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
181 if (avctx->extradata_size >= 18) {
182 s->decode_flags = AV_RL16(edata_ptr + 14);
183 channel_mask = AV_RL32(edata_ptr + 2);
184 s->bits_per_sample = AV_RL16(edata_ptr);
185 if (s->bits_per_sample == 16)
186 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
187 else if (s->bits_per_sample == 24) {
188 avctx->sample_fmt = AV_SAMPLE_FMT_S32;
189 av_log_missing_feature(avctx, "bit-depth higher than 16", 0);
190 return AVERROR_PATCHWELCOME;
192 av_log(avctx, AV_LOG_ERROR, "Unknown bit-depth: %d\n",
194 return AVERROR_INVALIDDATA;
196 /* dump the extradata */
197 for (i = 0; i < avctx->extradata_size; i++)
198 av_dlog(avctx, "[%x] ", avctx->extradata[i]);
199 av_dlog(avctx, "\n");
202 av_log_ask_for_sample(avctx, "Unsupported extradata size\n");
203 return AVERROR_INVALIDDATA;
207 s->log2_frame_size = av_log2(avctx->block_align) + 4;
210 s->skip_frame = 1; /* skip first frame */
212 s->len_prefix = s->decode_flags & 0x40;
215 s->samples_per_frame = 1 << ff_wma_get_frame_len_bits(avctx->sample_rate,
218 /* init previous block len */
219 for (i = 0; i < avctx->channels; i++)
220 s->channel[i].prev_block_len = s->samples_per_frame;
223 log2_max_num_subframes = (s->decode_flags & 0x38) >> 3;
224 s->max_num_subframes = 1 << log2_max_num_subframes;
225 s->max_subframe_len_bit = 0;
226 s->subframe_len_bits = av_log2(log2_max_num_subframes) + 1;
228 num_possible_block_sizes = log2_max_num_subframes + 1;
229 s->min_samples_per_subframe = s->samples_per_frame / s->max_num_subframes;
230 s->dynamic_range_compression = s->decode_flags & 0x80;
231 s->bV3RTM = s->decode_flags & 0x100;
233 if (s->max_num_subframes > MAX_SUBFRAMES) {
234 av_log(avctx, AV_LOG_ERROR, "invalid number of subframes %i\n",
235 s->max_num_subframes);
236 return AVERROR_INVALIDDATA;
239 s->num_channels = avctx->channels;
241 /* extract lfe channel position */
244 if (channel_mask & 8) {
246 for (mask = 1; mask < 16; mask <<= 1)
247 if (channel_mask & mask)
251 if (s->num_channels < 0) {
252 av_log(avctx, AV_LOG_ERROR, "invalid number of channels %d\n",
254 return AVERROR_INVALIDDATA;
255 } else if (s->num_channels > WMALL_MAX_CHANNELS) {
256 av_log_ask_for_sample(avctx, "unsupported number of channels\n");
257 return AVERROR_PATCHWELCOME;
260 avcodec_get_frame_defaults(&s->frame);
261 avctx->coded_frame = &s->frame;
262 avctx->channel_layout = channel_mask;
267 * @brief Decode the subframe length.
269 * @param offset sample offset in the frame
270 * @return decoded subframe length on success, < 0 in case of an error
272 static int decode_subframe_length(WmallDecodeCtx *s, int offset)
274 int frame_len_ratio, subframe_len, len;
276 /* no need to read from the bitstream when only one length is possible */
277 if (offset == s->samples_per_frame - s->min_samples_per_subframe)
278 return s->min_samples_per_subframe;
280 len = av_log2(s->max_num_subframes - 1) + 1;
281 frame_len_ratio = get_bits(&s->gb, len);
282 subframe_len = s->min_samples_per_subframe * (frame_len_ratio + 1);
284 /* sanity check the length */
285 if (subframe_len < s->min_samples_per_subframe ||
286 subframe_len > s->samples_per_frame) {
287 av_log(s->avctx, AV_LOG_ERROR, "broken frame: subframe_len %i\n",
289 return AVERROR_INVALIDDATA;
295 * @brief Decode how the data in the frame is split into subframes.
296 * Every WMA frame contains the encoded data for a fixed number of
297 * samples per channel. The data for every channel might be split
298 * into several subframes. This function will reconstruct the list of
299 * subframes for every channel.
301 * If the subframes are not evenly split, the algorithm estimates the
302 * channels with the lowest number of total samples.
303 * Afterwards, for each of these channels a bit is read from the
304 * bitstream that indicates if the channel contains a subframe with the
305 * next subframe size that is going to be read from the bitstream or not.
306 * If a channel contains such a subframe, the subframe size gets added to
307 * the channel's subframe list.
308 * The algorithm repeats these steps until the frame is properly divided
309 * between the individual channels.
312 * @return 0 on success, < 0 in case of an error
314 static int decode_tilehdr(WmallDecodeCtx *s)
316 uint16_t num_samples[WMALL_MAX_CHANNELS] = { 0 }; /* sum of samples for all currently known subframes of a channel */
317 uint8_t contains_subframe[WMALL_MAX_CHANNELS]; /* flag indicating if a channel contains the current subframe */
318 int channels_for_cur_subframe = s->num_channels; /* number of channels that contain the current subframe */
319 int fixed_channel_layout = 0; /* flag indicating that all channels use the same subfra2me offsets and sizes */
320 int min_channel_len = 0; /* smallest sum of samples (channels with this length will be processed first) */
323 /* reset tiling information */
324 for (c = 0; c < s->num_channels; c++)
325 s->channel[c].num_subframes = 0;
327 tile_aligned = get_bits1(&s->gb);
328 if (s->max_num_subframes == 1 || tile_aligned)
329 fixed_channel_layout = 1;
331 /* loop until the frame data is split between the subframes */
333 int subframe_len, in_use = 0;
335 /* check which channels contain the subframe */
336 for (c = 0; c < s->num_channels; c++) {
337 if (num_samples[c] == min_channel_len) {
338 if (fixed_channel_layout || channels_for_cur_subframe == 1 ||
339 (min_channel_len == s->samples_per_frame - s->min_samples_per_subframe)) {
340 contains_subframe[c] = in_use = 1;
342 if (get_bits1(&s->gb))
343 contains_subframe[c] = in_use = 1;
346 contains_subframe[c] = 0;
350 av_log(s->avctx, AV_LOG_ERROR,
351 "Found empty subframe\n");
352 return AVERROR_INVALIDDATA;
355 /* get subframe length, subframe_len == 0 is not allowed */
356 if ((subframe_len = decode_subframe_length(s, min_channel_len)) <= 0)
357 return AVERROR_INVALIDDATA;
358 /* add subframes to the individual channels and find new min_channel_len */
359 min_channel_len += subframe_len;
360 for (c = 0; c < s->num_channels; c++) {
361 WmallChannelCtx *chan = &s->channel[c];
363 if (contains_subframe[c]) {
364 if (chan->num_subframes >= MAX_SUBFRAMES) {
365 av_log(s->avctx, AV_LOG_ERROR,
366 "broken frame: num subframes > 31\n");
367 return AVERROR_INVALIDDATA;
369 chan->subframe_len[chan->num_subframes] = subframe_len;
370 num_samples[c] += subframe_len;
371 ++chan->num_subframes;
372 if (num_samples[c] > s->samples_per_frame) {
373 av_log(s->avctx, AV_LOG_ERROR, "broken frame: "
374 "channel len(%d) > samples_per_frame(%d)\n",
375 num_samples[c], s->samples_per_frame);
376 return AVERROR_INVALIDDATA;
378 } else if (num_samples[c] <= min_channel_len) {
379 if (num_samples[c] < min_channel_len) {
380 channels_for_cur_subframe = 0;
381 min_channel_len = num_samples[c];
383 ++channels_for_cur_subframe;
386 } while (min_channel_len < s->samples_per_frame);
388 for (c = 0; c < s->num_channels; c++) {
390 for (i = 0; i < s->channel[c].num_subframes; i++) {
391 s->channel[c].subframe_offsets[i] = offset;
392 offset += s->channel[c].subframe_len[i];
399 static void decode_ac_filter(WmallDecodeCtx *s)
402 s->acfilter_order = get_bits(&s->gb, 4) + 1;
403 s->acfilter_scaling = get_bits(&s->gb, 4);
405 for (i = 0; i < s->acfilter_order; i++)
406 s->acfilter_coeffs[i] = get_bits(&s->gb, s->acfilter_scaling) + 1;
409 static void decode_mclms(WmallDecodeCtx *s)
411 s->mclms_order = (get_bits(&s->gb, 4) + 1) * 2;
412 s->mclms_scaling = get_bits(&s->gb, 4);
413 if (get_bits1(&s->gb)) {
414 int i, send_coef_bits;
415 int cbits = av_log2(s->mclms_scaling + 1);
416 if (1 << cbits < s->mclms_scaling + 1)
419 send_coef_bits = (cbits ? get_bits(&s->gb, cbits) : 0) + 2;
421 for (i = 0; i < s->mclms_order * s->num_channels * s->num_channels; i++)
422 s->mclms_coeffs[i] = get_bits(&s->gb, send_coef_bits);
424 for (i = 0; i < s->num_channels; i++) {
426 for (c = 0; c < i; c++)
427 s->mclms_coeffs_cur[i * s->num_channels + c] = get_bits(&s->gb, send_coef_bits);
432 static int decode_cdlms(WmallDecodeCtx *s)
435 int cdlms_send_coef = get_bits1(&s->gb);
437 for (c = 0; c < s->num_channels; c++) {
438 s->cdlms_ttl[c] = get_bits(&s->gb, 3) + 1;
439 for (i = 0; i < s->cdlms_ttl[c]; i++) {
440 s->cdlms[c][i].order = (get_bits(&s->gb, 7) + 1) * 8;
441 if (s->cdlms[c][i].order > MAX_ORDER) {
442 av_log(s->avctx, AV_LOG_ERROR,
443 "Order[%d][%d] %d > max (%d), not supported\n",
444 c, i, s->cdlms[c][i].order, MAX_ORDER);
445 s->cdlms[0][0].order = 0;
446 return AVERROR_INVALIDDATA;
450 for (i = 0; i < s->cdlms_ttl[c]; i++)
451 s->cdlms[c][i].scaling = get_bits(&s->gb, 4);
453 if (cdlms_send_coef) {
454 for (i = 0; i < s->cdlms_ttl[c]; i++) {
455 int cbits, shift_l, shift_r, j;
456 cbits = av_log2(s->cdlms[c][i].order);
457 if ((1 << cbits) < s->cdlms[c][i].order)
459 s->cdlms[c][i].coefsend = get_bits(&s->gb, cbits) + 1;
461 cbits = av_log2(s->cdlms[c][i].scaling + 1);
462 if ((1 << cbits) < s->cdlms[c][i].scaling + 1)
465 s->cdlms[c][i].bitsend = get_bits(&s->gb, cbits) + 2;
466 shift_l = 32 - s->cdlms[c][i].bitsend;
467 shift_r = 32 - s->cdlms[c][i].scaling - 2;
468 for (j = 0; j < s->cdlms[c][i].coefsend; j++)
469 s->cdlms[c][i].coefs[j] =
470 (get_bits(&s->gb, s->cdlms[c][i].bitsend) << shift_l) >> shift_r;
478 static int decode_channel_residues(WmallDecodeCtx *s, int ch, int tile_size)
481 unsigned int ave_mean;
482 s->transient[ch] = get_bits1(&s->gb);
483 if (s->transient[ch]) {
484 s->transient_pos[ch] = get_bits(&s->gb, av_log2(tile_size));
485 if (s->transient_pos[ch])
486 s->transient[ch] = 0;
487 s->channel[ch].transient_counter =
488 FFMAX(s->channel[ch].transient_counter, s->samples_per_frame / 2);
489 } else if (s->channel[ch].transient_counter)
490 s->transient[ch] = 1;
492 if (s->seekable_tile) {
493 ave_mean = get_bits(&s->gb, s->bits_per_sample);
494 s->ave_sum[ch] = ave_mean << (s->movave_scaling + 1);
497 if (s->seekable_tile) {
498 if (s->do_inter_ch_decorr)
499 s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample + 1);
501 s->channel_residues[ch][0] = get_sbits(&s->gb, s->bits_per_sample);
504 for (; i < tile_size; i++) {
505 int quo = 0, rem, rem_bits, residue;
506 while(get_bits1(&s->gb)) {
508 if (get_bits_left(&s->gb) <= 0)
512 quo += get_bits_long(&s->gb, get_bits(&s->gb, 5) + 1);
514 ave_mean = (s->ave_sum[ch] + (1 << s->movave_scaling)) >> (s->movave_scaling + 1);
518 rem_bits = av_ceil_log2(ave_mean);
519 rem = rem_bits ? get_bits(&s->gb, rem_bits) : 0;
520 residue = (quo << rem_bits) + rem;
523 s->ave_sum[ch] = residue + s->ave_sum[ch] -
524 (s->ave_sum[ch] >> s->movave_scaling);
527 residue = -(residue >> 1) - 1;
529 residue = residue >> 1;
530 s->channel_residues[ch][i] = residue;
537 static void decode_lpc(WmallDecodeCtx *s)
540 s->lpc_order = get_bits(&s->gb, 5) + 1;
541 s->lpc_scaling = get_bits(&s->gb, 4);
542 s->lpc_intbits = get_bits(&s->gb, 3) + 1;
543 cbits = s->lpc_scaling + s->lpc_intbits;
544 for (ch = 0; ch < s->num_channels; ch++)
545 for (i = 0; i < s->lpc_order; i++)
546 s->lpc_coefs[ch][i] = get_sbits(&s->gb, cbits);
549 static void clear_codec_buffers(WmallDecodeCtx *s)
553 memset(s->acfilter_coeffs, 0, sizeof(s->acfilter_coeffs));
554 memset(s->acfilter_prevvalues, 0, sizeof(s->acfilter_prevvalues));
555 memset(s->lpc_coefs, 0, sizeof(s->lpc_coefs));
557 memset(s->mclms_coeffs, 0, sizeof(s->mclms_coeffs));
558 memset(s->mclms_coeffs_cur, 0, sizeof(s->mclms_coeffs_cur));
559 memset(s->mclms_prevvalues, 0, sizeof(s->mclms_prevvalues));
560 memset(s->mclms_updates, 0, sizeof(s->mclms_updates));
562 for (ich = 0; ich < s->num_channels; ich++) {
563 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++) {
564 memset(s->cdlms[ich][ilms].coefs, 0,
565 sizeof(s->cdlms[ich][ilms].coefs));
566 memset(s->cdlms[ich][ilms].lms_prevvalues, 0,
567 sizeof(s->cdlms[ich][ilms].lms_prevvalues));
568 memset(s->cdlms[ich][ilms].lms_updates, 0,
569 sizeof(s->cdlms[ich][ilms].lms_updates));
576 * @brief Reset filter parameters and transient area at new seekable tile.
578 static void reset_codec(WmallDecodeCtx *s)
581 s->mclms_recent = s->mclms_order * s->num_channels;
582 for (ich = 0; ich < s->num_channels; ich++) {
583 for (ilms = 0; ilms < s->cdlms_ttl[ich]; ilms++)
584 s->cdlms[ich][ilms].recent = s->cdlms[ich][ilms].order;
585 /* first sample of a seekable subframe is considered as the starting of
586 a transient area which is samples_per_frame samples long */
587 s->channel[ich].transient_counter = s->samples_per_frame;
588 s->transient[ich] = 1;
589 s->transient_pos[ich] = 0;
593 static void mclms_update(WmallDecodeCtx *s, int icoef, int *pred)
595 int i, j, ich, pred_error;
596 int order = s->mclms_order;
597 int num_channels = s->num_channels;
598 int range = 1 << (s->bits_per_sample - 1);
600 for (ich = 0; ich < num_channels; ich++) {
601 pred_error = s->channel_residues[ich][icoef] - pred[ich];
602 if (pred_error > 0) {
603 for (i = 0; i < order * num_channels; i++)
604 s->mclms_coeffs[i + ich * order * num_channels] +=
605 s->mclms_updates[s->mclms_recent + i];
606 for (j = 0; j < ich; j++) {
607 if (s->channel_residues[j][icoef] > 0)
608 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
609 else if (s->channel_residues[j][icoef] < 0)
610 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
612 } else if (pred_error < 0) {
613 for (i = 0; i < order * num_channels; i++)
614 s->mclms_coeffs[i + ich * order * num_channels] -=
615 s->mclms_updates[s->mclms_recent + i];
616 for (j = 0; j < ich; j++) {
617 if (s->channel_residues[j][icoef] > 0)
618 s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
619 else if (s->channel_residues[j][icoef] < 0)
620 s->mclms_coeffs_cur[ich * num_channels + j] += 1;
625 for (ich = num_channels - 1; ich >= 0; ich--) {
627 s->mclms_prevvalues[s->mclms_recent] = s->channel_residues[ich][icoef];
628 if (s->channel_residues[ich][icoef] > range - 1)
629 s->mclms_prevvalues[s->mclms_recent] = range - 1;
630 else if (s->channel_residues[ich][icoef] < -range)
631 s->mclms_prevvalues[s->mclms_recent] = -range;
633 s->mclms_updates[s->mclms_recent] = 0;
634 if (s->channel_residues[ich][icoef] > 0)
635 s->mclms_updates[s->mclms_recent] = 1;
636 else if (s->channel_residues[ich][icoef] < 0)
637 s->mclms_updates[s->mclms_recent] = -1;
640 if (s->mclms_recent == 0) {
641 memcpy(&s->mclms_prevvalues[order * num_channels],
643 2 * order * num_channels);
644 memcpy(&s->mclms_updates[order * num_channels],
646 2 * order * num_channels);
647 s->mclms_recent = num_channels * order;
651 static void mclms_predict(WmallDecodeCtx *s, int icoef, int *pred)
654 int order = s->mclms_order;
655 int num_channels = s->num_channels;
657 for (ich = 0; ich < num_channels; ich++) {
658 if (!s->is_channel_coded[ich])
661 for (i = 0; i < order * num_channels; i++)
662 pred[ich] += s->mclms_prevvalues[i + s->mclms_recent] *
663 s->mclms_coeffs[i + order * num_channels * ich];
664 for (i = 0; i < ich; i++)
665 pred[ich] += s->channel_residues[i][icoef] *
666 s->mclms_coeffs_cur[i + num_channels * ich];
667 pred[ich] += 1 << s->mclms_scaling - 1;
668 pred[ich] >>= s->mclms_scaling;
669 s->channel_residues[ich][icoef] += pred[ich];
673 static void revert_mclms(WmallDecodeCtx *s, int tile_size)
675 int icoef, pred[WMALL_MAX_CHANNELS] = { 0 };
676 for (icoef = 0; icoef < tile_size; icoef++) {
677 mclms_predict(s, icoef, pred);
678 mclms_update(s, icoef, pred);
682 static int lms_predict(WmallDecodeCtx *s, int ich, int ilms)
685 int recent = s->cdlms[ich][ilms].recent;
687 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
688 pred += s->cdlms[ich][ilms].coefs[icoef] *
689 s->cdlms[ich][ilms].lms_prevvalues[icoef + recent];
694 static void lms_update(WmallDecodeCtx *s, int ich, int ilms,
695 int input, int residue)
698 int recent = s->cdlms[ich][ilms].recent;
699 int range = 1 << s->bits_per_sample - 1;
702 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
703 s->cdlms[ich][ilms].coefs[icoef] -=
704 s->cdlms[ich][ilms].lms_updates[icoef + recent];
705 } else if (residue > 0) {
706 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
707 s->cdlms[ich][ilms].coefs[icoef] +=
708 s->cdlms[ich][ilms].lms_updates[icoef + recent];
714 memcpy(&s->cdlms[ich][ilms].lms_prevvalues[s->cdlms[ich][ilms].order],
715 s->cdlms[ich][ilms].lms_prevvalues,
716 2 * s->cdlms[ich][ilms].order);
717 memcpy(&s->cdlms[ich][ilms].lms_updates[s->cdlms[ich][ilms].order],
718 s->cdlms[ich][ilms].lms_updates,
719 2 * s->cdlms[ich][ilms].order);
720 recent = s->cdlms[ich][ilms].order - 1;
723 s->cdlms[ich][ilms].lms_prevvalues[recent] = av_clip(input, -range, range - 1);
725 s->cdlms[ich][ilms].lms_updates[recent] = 0;
727 s->cdlms[ich][ilms].lms_updates[recent] = -s->update_speed[ich];
729 s->cdlms[ich][ilms].lms_updates[recent] = s->update_speed[ich];
731 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 4)] >>= 2;
732 s->cdlms[ich][ilms].lms_updates[recent + (s->cdlms[ich][ilms].order >> 3)] >>= 1;
733 s->cdlms[ich][ilms].recent = recent;
736 static void use_high_update_speed(WmallDecodeCtx *s, int ich)
738 int ilms, recent, icoef;
739 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
740 recent = s->cdlms[ich][ilms].recent;
741 if (s->update_speed[ich] == 16)
744 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
745 s->cdlms[ich][ilms].lms_updates[icoef + recent] *= 2;
747 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
748 s->cdlms[ich][ilms].lms_updates[icoef] *= 2;
751 s->update_speed[ich] = 16;
754 static void use_normal_update_speed(WmallDecodeCtx *s, int ich)
756 int ilms, recent, icoef;
757 for (ilms = s->cdlms_ttl[ich] - 1; ilms >= 0; ilms--) {
758 recent = s->cdlms[ich][ilms].recent;
759 if (s->update_speed[ich] == 8)
762 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
763 s->cdlms[ich][ilms].lms_updates[icoef + recent] /= 2;
765 for (icoef = 0; icoef < s->cdlms[ich][ilms].order; icoef++)
766 s->cdlms[ich][ilms].lms_updates[icoef] /= 2;
768 s->update_speed[ich] = 8;
771 static void revert_cdlms(WmallDecodeCtx *s, int ch,
772 int coef_begin, int coef_end)
774 int icoef, pred, ilms, num_lms, residue, input;
776 num_lms = s->cdlms_ttl[ch];
777 for (ilms = num_lms - 1; ilms >= 0; ilms--) {
778 for (icoef = coef_begin; icoef < coef_end; icoef++) {
779 pred = 1 << (s->cdlms[ch][ilms].scaling - 1);
780 residue = s->channel_residues[ch][icoef];
781 pred += lms_predict(s, ch, ilms);
782 input = residue + (pred >> s->cdlms[ch][ilms].scaling);
783 lms_update(s, ch, ilms, input, residue);
784 s->channel_residues[ch][icoef] = input;
789 static void revert_inter_ch_decorr(WmallDecodeCtx *s, int tile_size)
791 if (s->num_channels != 2)
793 else if (s->is_channel_coded[0] && s->is_channel_coded[1]) {
795 for (icoef = 0; icoef < tile_size; icoef++) {
796 s->channel_residues[0][icoef] -= s->channel_residues[1][icoef] >> 1;
797 s->channel_residues[1][icoef] += s->channel_residues[0][icoef];
802 static void revert_acfilter(WmallDecodeCtx *s, int tile_size)
805 int64_t *filter_coeffs = s->acfilter_coeffs;
806 int scaling = s->acfilter_scaling;
807 int order = s->acfilter_order;
809 for (ich = 0; ich < s->num_channels; ich++) {
810 int *prevvalues = s->acfilter_prevvalues[ich];
811 for (i = 0; i < order; i++) {
813 for (j = 0; j < order; j++) {
815 pred += filter_coeffs[j] * prevvalues[j - i];
817 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
820 s->channel_residues[ich][i] += pred;
822 for (i = order; i < tile_size; i++) {
824 for (j = 0; j < order; j++)
825 pred += s->channel_residues[ich][i - j - 1] * filter_coeffs[j];
827 s->channel_residues[ich][i] += pred;
829 for (j = 0; j < order; j++)
830 prevvalues[j] = s->channel_residues[ich][tile_size - j - 1];
834 static int decode_subframe(WmallDecodeCtx *s)
836 int offset = s->samples_per_frame;
837 int subframe_len = s->samples_per_frame;
838 int total_samples = s->samples_per_frame * s->num_channels;
839 int i, j, rawpcm_tile, padding_zeroes, res;
841 s->subframe_offset = get_bits_count(&s->gb);
843 /* reset channel context and find the next block offset and size
844 == the next block of the channel with the smallest number of
846 for (i = 0; i < s->num_channels; i++) {
847 if (offset > s->channel[i].decoded_samples) {
848 offset = s->channel[i].decoded_samples;
850 s->channel[i].subframe_len[s->channel[i].cur_subframe];
854 /* get a list of all channels that contain the estimated block */
855 s->channels_for_cur_subframe = 0;
856 for (i = 0; i < s->num_channels; i++) {
857 const int cur_subframe = s->channel[i].cur_subframe;
858 /* subtract already processed samples */
859 total_samples -= s->channel[i].decoded_samples;
861 /* and count if there are multiple subframes that match our profile */
862 if (offset == s->channel[i].decoded_samples &&
863 subframe_len == s->channel[i].subframe_len[cur_subframe]) {
864 total_samples -= s->channel[i].subframe_len[cur_subframe];
865 s->channel[i].decoded_samples +=
866 s->channel[i].subframe_len[cur_subframe];
867 s->channel_indexes_for_cur_subframe[s->channels_for_cur_subframe] = i;
868 ++s->channels_for_cur_subframe;
872 /* check if the frame will be complete after processing the
875 s->parsed_all_subframes = 1;
878 s->seekable_tile = get_bits1(&s->gb);
879 if (s->seekable_tile) {
880 clear_codec_buffers(s);
882 s->do_arith_coding = get_bits1(&s->gb);
883 if (s->do_arith_coding) {
884 av_log_missing_feature(s->avctx, "arithmetic coding", 1);
885 return AVERROR_PATCHWELCOME;
887 s->do_ac_filter = get_bits1(&s->gb);
888 s->do_inter_ch_decorr = get_bits1(&s->gb);
889 s->do_mclms = get_bits1(&s->gb);
897 if ((res = decode_cdlms(s)) < 0)
899 s->movave_scaling = get_bits(&s->gb, 3);
900 s->quant_stepsize = get_bits(&s->gb, 8) + 1;
903 } else if (!s->cdlms[0][0].order) {
904 av_log(s->avctx, AV_LOG_DEBUG,
905 "Waiting for seekable tile\n");
909 rawpcm_tile = get_bits1(&s->gb);
911 for (i = 0; i < s->num_channels; i++)
912 s->is_channel_coded[i] = 1;
915 for (i = 0; i < s->num_channels; i++)
916 s->is_channel_coded[i] = get_bits1(&s->gb);
920 s->do_lpc = get_bits1(&s->gb);
923 av_log_ask_for_sample(s->avctx, "Inverse LPC filter not "
924 "implemented. Expect wrong output.\n");
931 if (get_bits1(&s->gb))
932 padding_zeroes = get_bits(&s->gb, 5);
937 int bits = s->bits_per_sample - padding_zeroes;
938 av_dlog(s->avctx, "RAWPCM %d bits per sample. "
939 "total %d bits, remain=%d\n", bits,
940 bits * s->num_channels * subframe_len, get_bits_count(&s->gb));
941 for (i = 0; i < s->num_channels; i++)
942 for (j = 0; j < subframe_len; j++)
943 s->channel_coeffs[i][j] = get_sbits(&s->gb, bits);
945 for (i = 0; i < s->num_channels; i++)
946 if (s->is_channel_coded[i]) {
947 decode_channel_residues(s, i, subframe_len);
948 if (s->seekable_tile)
949 use_high_update_speed(s, i);
951 use_normal_update_speed(s, i);
952 revert_cdlms(s, i, 0, subframe_len);
956 revert_mclms(s, subframe_len);
957 if (s->do_inter_ch_decorr)
958 revert_inter_ch_decorr(s, subframe_len);
960 revert_acfilter(s, subframe_len);
963 if (s->quant_stepsize != 1)
964 for (i = 0; i < s->num_channels; i++)
965 for (j = 0; j < subframe_len; j++)
966 s->channel_residues[i][j] *= s->quant_stepsize;
968 /* Write to proper output buffer depending on bit-depth */
969 for (i = 0; i < s->channels_for_cur_subframe; i++) {
970 int c = s->channel_indexes_for_cur_subframe[i];
971 int subframe_len = s->channel[c].subframe_len[s->channel[c].cur_subframe];
973 for (j = 0; j < subframe_len; j++) {
974 if (s->bits_per_sample == 16) {
975 *s->samples_16[c] = (int16_t) s->channel_residues[c][j];
976 s->samples_16[c] += s->num_channels;
978 *s->samples_32[c] = s->channel_residues[c][j];
979 s->samples_32[c] += s->num_channels;
984 /* handled one subframe */
985 for (i = 0; i < s->channels_for_cur_subframe; i++) {
986 int c = s->channel_indexes_for_cur_subframe[i];
987 if (s->channel[c].cur_subframe >= s->channel[c].num_subframes) {
988 av_log(s->avctx, AV_LOG_ERROR, "broken subframe\n");
989 return AVERROR_INVALIDDATA;
991 ++s->channel[c].cur_subframe;
997 * @brief Decode one WMA frame.
998 * @param s codec context
999 * @return 0 if the trailer bit indicates that this is the last frame,
1000 * 1 if there are additional frames
1002 static int decode_frame(WmallDecodeCtx *s)
1004 GetBitContext* gb = &s->gb;
1005 int more_frames = 0, len = 0, i, ret;
1007 s->frame.nb_samples = s->samples_per_frame;
1008 if ((ret = s->avctx->get_buffer(s->avctx, &s->frame)) < 0) {
1009 /* return an error if no frame could be decoded at all */
1010 av_log(s->avctx, AV_LOG_ERROR,
1011 "not enough space for the output samples\n");
1015 for (i = 0; i < s->num_channels; i++) {
1016 s->samples_16[i] = (int16_t *)s->frame.data[0] + i;
1017 s->samples_32[i] = (int32_t *)s->frame.data[0] + i;
1020 /* get frame length */
1022 len = get_bits(gb, s->log2_frame_size);
1024 /* decode tile information */
1025 if (decode_tilehdr(s)) {
1031 if (s->dynamic_range_compression)
1032 s->drc_gain = get_bits(gb, 8);
1034 /* no idea what these are for, might be the number of samples
1035 that need to be skipped at the beginning or end of a stream */
1036 if (get_bits1(gb)) {
1039 /* usually true for the first frame */
1040 if (get_bits1(gb)) {
1041 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1042 av_dlog(s->avctx, "start skip: %i\n", skip);
1045 /* sometimes true for the last frame */
1046 if (get_bits1(gb)) {
1047 skip = get_bits(gb, av_log2(s->samples_per_frame * 2));
1048 av_dlog(s->avctx, "end skip: %i\n", skip);
1053 /* reset subframe states */
1054 s->parsed_all_subframes = 0;
1055 for (i = 0; i < s->num_channels; i++) {
1056 s->channel[i].decoded_samples = 0;
1057 s->channel[i].cur_subframe = 0;
1060 /* decode all subframes */
1061 while (!s->parsed_all_subframes) {
1062 if (decode_subframe(s) < 0) {
1068 av_dlog(s->avctx, "Frame done\n");
1073 if (s->len_prefix) {
1074 if (len != (get_bits_count(gb) - s->frame_offset) + 2) {
1075 /* FIXME: not sure if this is always an error */
1076 av_log(s->avctx, AV_LOG_ERROR,
1077 "frame[%i] would have to skip %i bits\n", s->frame_num,
1078 len - (get_bits_count(gb) - s->frame_offset) - 1);
1083 /* skip the rest of the frame data */
1084 skip_bits_long(gb, len - (get_bits_count(gb) - s->frame_offset) - 1);
1087 /* decode trailer bit */
1088 more_frames = get_bits1(gb);
1094 * @brief Calculate remaining input buffer length.
1095 * @param s codec context
1096 * @param gb bitstream reader context
1097 * @return remaining size in bits
1099 static int remaining_bits(WmallDecodeCtx *s, GetBitContext *gb)
1101 return s->buf_bit_size - get_bits_count(gb);
1105 * @brief Fill the bit reservoir with a (partial) frame.
1106 * @param s codec context
1107 * @param gb bitstream reader context
1108 * @param len length of the partial frame
1109 * @param append decides whether to reset the buffer or not
1111 static void save_bits(WmallDecodeCtx *s, GetBitContext* gb, int len,
1117 /* when the frame data does not need to be concatenated, the input buffer
1118 is reset and additional bits from the previous frame are copied
1119 and skipped later so that a fast byte copy is possible */
1122 s->frame_offset = get_bits_count(gb) & 7;
1123 s->num_saved_bits = s->frame_offset;
1124 init_put_bits(&s->pb, s->frame_data, MAX_FRAMESIZE);
1127 buflen = (s->num_saved_bits + len + 8) >> 3;
1129 if (len <= 0 || buflen > MAX_FRAMESIZE) {
1130 av_log_ask_for_sample(s->avctx, "input buffer too small\n");
1135 s->num_saved_bits += len;
1137 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3),
1140 int align = 8 - (get_bits_count(gb) & 7);
1141 align = FFMIN(align, len);
1142 put_bits(&s->pb, align, get_bits(gb, align));
1144 avpriv_copy_bits(&s->pb, gb->buffer + (get_bits_count(gb) >> 3), len);
1146 skip_bits_long(gb, len);
1149 flush_put_bits(&tmp);
1151 init_get_bits(&s->gb, s->frame_data, s->num_saved_bits);
1152 skip_bits(&s->gb, s->frame_offset);
1156 * @brief Decode a single WMA packet.
1157 * @param avctx codec context
1158 * @param data the output buffer
1159 * @param data_size number of bytes that were written to the output buffer
1160 * @param avpkt input packet
1161 * @return number of bytes that were read from the input buffer
1163 static int decode_packet(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1166 WmallDecodeCtx *s = avctx->priv_data;
1167 GetBitContext* gb = &s->pgb;
1168 const uint8_t* buf = avpkt->data;
1169 int buf_size = avpkt->size;
1170 int num_bits_prev_frame, packet_sequence_number,
1171 seekable_frame_in_packet, spliced_packet;
1173 if (s->packet_done || s->packet_loss) {
1176 /* sanity check for the buffer length */
1177 if (buf_size < avctx->block_align)
1180 s->next_packet_start = buf_size - avctx->block_align;
1181 buf_size = avctx->block_align;
1182 s->buf_bit_size = buf_size << 3;
1184 /* parse packet header */
1185 init_get_bits(gb, buf, s->buf_bit_size);
1186 packet_sequence_number = get_bits(gb, 4);
1187 seekable_frame_in_packet = get_bits1(gb);
1188 spliced_packet = get_bits1(gb);
1190 /* get number of bits that need to be added to the previous frame */
1191 num_bits_prev_frame = get_bits(gb, s->log2_frame_size);
1193 /* check for packet loss */
1194 if (!s->packet_loss &&
1195 ((s->packet_sequence_number + 1) & 0xF) != packet_sequence_number) {
1197 av_log(avctx, AV_LOG_ERROR, "Packet loss detected! seq %x vs %x\n",
1198 s->packet_sequence_number, packet_sequence_number);
1200 s->packet_sequence_number = packet_sequence_number;
1202 if (num_bits_prev_frame > 0) {
1203 int remaining_packet_bits = s->buf_bit_size - get_bits_count(gb);
1204 if (num_bits_prev_frame >= remaining_packet_bits) {
1205 num_bits_prev_frame = remaining_packet_bits;
1209 /* Append the previous frame data to the remaining data from the
1210 * previous packet to create a full frame. */
1211 save_bits(s, gb, num_bits_prev_frame, 1);
1213 /* decode the cross packet frame if it is valid */
1214 if (!s->packet_loss)
1216 } else if (s->num_saved_bits - s->frame_offset) {
1217 av_dlog(avctx, "ignoring %x previously saved bits\n",
1218 s->num_saved_bits - s->frame_offset);
1221 if (s->packet_loss) {
1222 /* Reset number of saved bits so that the decoder does not start
1223 * to decode incomplete frames in the s->len_prefix == 0 case. */
1224 s->num_saved_bits = 0;
1231 s->buf_bit_size = (avpkt->size - s->next_packet_start) << 3;
1232 init_get_bits(gb, avpkt->data, s->buf_bit_size);
1233 skip_bits(gb, s->packet_offset);
1235 if (s->len_prefix && remaining_bits(s, gb) > s->log2_frame_size &&
1236 (frame_size = show_bits(gb, s->log2_frame_size)) &&
1237 frame_size <= remaining_bits(s, gb)) {
1238 save_bits(s, gb, frame_size, 0);
1239 s->packet_done = !decode_frame(s);
1240 } else if (!s->len_prefix
1241 && s->num_saved_bits > get_bits_count(&s->gb)) {
1242 /* when the frames do not have a length prefix, we don't know the
1243 * compressed length of the individual frames however, we know what
1244 * part of a new packet belongs to the previous frame therefore we
1245 * save the incoming packet first, then we append the "previous
1246 * frame" data from the next packet so that we get a buffer that
1247 * only contains full frames */
1248 s->packet_done = !decode_frame(s);
1254 if (s->packet_done && !s->packet_loss &&
1255 remaining_bits(s, gb) > 0) {
1256 /* save the rest of the data so that it can be decoded
1257 * with the next packet */
1258 save_bits(s, gb, remaining_bits(s, gb), 0);
1261 *(AVFrame *)data = s->frame;
1262 *got_frame_ptr = s->frame.nb_samples > 0;
1263 s->packet_offset = get_bits_count(gb) & 7;
1265 return (s->packet_loss) ? AVERROR_INVALIDDATA : get_bits_count(gb) >> 3;
1269 AVCodec ff_wmalossless_decoder = {
1270 .name = "wmalossless",
1271 .type = AVMEDIA_TYPE_AUDIO,
1272 .id = CODEC_ID_WMALOSSLESS,
1273 .priv_data_size = sizeof(WmallDecodeCtx),
1274 .init = decode_init,
1275 .decode = decode_packet,
1276 .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1 | CODEC_CAP_DELAY,
1277 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio Lossless"),