1 /*
2 * Windows Media Audio Voice decoder.
3 * Copyright (c) 2009 Ronald S. Bultje
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * @brief Windows Media Audio Voice compatible decoder
25 * @author Ronald S. Bultje <rsbultje@gmail.com>
26 */
27
28 #include <math.h>
29
47
48 #define MAX_BLOCKS 8 ///< maximum number of blocks per frame
49 #define MAX_LSPS 16
///< maximum filter order
50 #define MAX_LSPS_ALIGN16 16
///< same as #MAX_LSPS; needs to be multiple
51 ///< of 16 for ASM input buffer alignment
52 #define MAX_FRAMES 3
///< maximum number of frames per superframe
53 #define MAX_FRAMESIZE 160
///< maximum number of samples per frame
54 #define MAX_SIGNAL_HISTORY 416
///< maximum excitation signal history
55 #define MAX_SFRAMESIZE (MAX_FRAMESIZE * MAX_FRAMES)
56 ///< maximum number of samples per superframe
57 #define SFRAME_CACHE_MAXSIZE 256 ///< maximum cache size for frame data that
58 ///< was split over two packets
59 #define VLC_NBITS 6
///< number of bits to read per VLC iteration
60
61 /**
62 * Frame type VLC coding.
63 */
65
66 /**
67 * Adaptive codebook types.
68 */
69 enum {
72 ///< we interpolate to get a per-sample pitch.
73 ///< Signal is generated using an asymmetric sinc
74 ///< window function
75 ///< @note see #wmavoice_ipol1_coeffs
77 ///< a Hamming sinc window function
78 ///< @note see #wmavoice_ipol2_coeffs
79 };
80
81 /**
82 * Fixed codebook types.
83 */
84 enum {
86 ///< generated from a hardcoded (fixed) codebook
87 ///< with per-frame (low) gain values
89 ///< gain values
91 ///< used in particular for low-bitrate streams
93 ///< combinations of either single pulses or
94 ///< pulse pairs
95 };
96
97 /**
98 * Description of frame types.
99 */
101 uint8_t
n_blocks;
///< amount of blocks per frame (each block
102 ///< (contains 160/#n_blocks samples)
104 uint8_t
acb_type;
///< Adaptive codebook type (ACB_TYPE_*)
105 uint8_t
fcb_type;
///< Fixed codebook type (FCB_TYPE_*)
106 uint8_t
dbl_pulses;
///< how many pulse vectors have pulse pairs
107 ///< (rather than just one single pulse)
108 ///< only if #fcb_type == #FCB_TYPE_EXC_PULSES
127 };
128
129 /**
130 * WMA Voice decoding context.
131 */
133 /**
134 * @name Global values specified in the stream header / extradata or used all over.
135 * @{
136 */
138 ///< it contains the extradata from the
139 ///< demuxer. During decoding, it contains
140 ///< packet data.
141 int8_t
vbm_tree[25];
///< converts VLC codes to frame type
142
144 ///< #spillover_nbits in the packet header
145 ///< = ceil(log2(ctx->block_align << 3))
147 ///< prediction (through ACB)
148
149 /* postfilter specific values */
150 int do_apf;
///< whether to apply the averaged
151 ///< projection filter (APF)
153 ///< [0-11]
155 ///< Wiener filter coefficients (postfilter)
156 int dc_level;
///< Predicted amount of DC noise, based
157 ///< on which a DC removal filter is used
158
159 int lsps;
///< number of LSPs per frame [10 or 16]
162 ///< [0, 1]
163
167 ///< pitch value in the frame header
169 ///< first block's pitch value
172 ///< delta pitch between this and the last
173 ///< block's pitch value, used in all but
174 ///< first block
176 ///< from -this to +this-1)
178 ///< conversion
179
180 /**
181 * @}
182 *
183 * @name Packet values specified in the packet header or related to a packet.
184 *
185 * A packet is considered to be a single unit of data provided to this
186 * decoder by the demuxer.
187 * @{
188 */
190 ///< last superframe preceding this
191 ///< packet's first full superframe (useful
192 ///< for re-synchronization also)
194 ///< LSPs that cover all frames, encoded as
195 ///< independent and residual LSPs; if not
196 ///< set, each frame contains its own, fully
197 ///< independent, LSPs
199 ///< to #wmavoice_decode_packet() (since
200 ///< they're part of the previous superframe)
201
203 ///< cache for superframe data split over
204 ///< multiple packets
206 ///< (incomplete) superframe from a previous
207 ///< packet that spilled over in the current
208 ///< packet; specifies the amount of bits in
209 ///< #sframe_cache
211
212 /**
213 * @}
214 *
215 * @name Frame and superframe values
216 * Superframe and frame data - these can change from frame to frame,
217 * although some of them do in that case serve as a cache / history for
218 * the next frame or superframe.
219 * @{
220 */
222 ///< superframe
226 ///< << 16) / #MAX_FRAMESIZE
228
230 ///< 8 bits (instead of 6)
232 ///< can apply the pulse, relative to the
233 ///< value in aw_first_pulse_off. The exact
234 ///< position of the first AW-pulse is within
235 ///< [pulse_off, pulse_off + this], and
236 ///< depends on bitstream values; [16 or 24]
238 ///< that this number can be negative (in
239 ///< which case it basically means "zero")
241 ///< apply AW-pulses, or -0xff if unset
243 ///< second block) at which pulses should
244 ///< start to be positioned, serves as a
245 ///< cache for pitch-adaptive window pulses
246 ///< between blocks
247
249 ///< only used for comfort noise in #pRNG()
253 ///< previous superframes, used as a history
254 ///< for signal generation
256 /**
257 * @}
258 *
259 * @name Postfilter values
260 *
261 * Variables used for postfilter implementation, mostly history for
262 * smoothing and so on, and context variables for FFT/iFFT.
263 * @{
264 */
269 float sin[511],
cos[511];
///< 8-bit cosine/sine windows over [-pi,pi]
270 ///< range
272 ///< #adaptive_gain_control()
274 /// zero filter output (i.e. excitation) by postfilter
278 /// aligned buffer for LPC tilting
280 /// aligned buffer for denoise coefficients
282 /// aligned buffer for postfilter speech synthesis
284 /**
285 * @}
286 */
288
289 /**
290 * Set up the variable bit mode (VBM) tree from container extradata.
291 * @param gb bit I/O context.
292 * The bit context (s->gb) should be loaded with byte 23-46 of the
293 * container extradata (i.e. the ones containing the VBM tree).
294 * @param vbm_tree pointer to array to which the decoded VBM tree will be
295 * written.
296 * @return 0 on success, <0 on error.
297 */
299 {
300 int cntr[8] = { 0 }, n, res;
301
302 memset(vbm_tree, 0xff, sizeof(vbm_tree[0]) * 25);
303 for (n = 0; n < 17; n++) {
305 if (cntr[res] > 3) // should be >= 3 + (res == 7))
306 return -1;
307 vbm_tree[res * 3 + cntr[res]++] = n;
308 }
309 return 0;
310 }
311
313 {
314 static const uint8_t
bits[] = {
315 2, 2, 2, 4, 4, 4,
316 6, 6, 6, 8, 8, 8,
317 10, 10, 10, 12, 12, 12,
318 14, 14, 14, 14
319 };
320
323 1,
NULL, 0, 0, 0, 0);
324 }
325
327 {
329 int n;
330
331 s->postfilter_agc = 0;
332 s->sframe_cache_size = 0;
333 s->skip_bits_next = 0;
334 for (n = 0; n <
s->lsps; n++)
335 s->prev_lsps[n] =
M_PI * (n + 1.0) / (
s->lsps + 1.0);
336 memset(
s->excitation_history, 0,
338 memset(
s->synth_history, 0,
340 memset(
s->gain_pred_err, 0,
341 sizeof(
s->gain_pred_err));
342
345 sizeof(*
s->synth_filter_out_buf) *
s->lsps);
346 memset(
s->dcf_mem, 0,
347 sizeof(*
s->dcf_mem) * 2);
348 memset(
s->zero_exc_pf, 0,
349 sizeof(*
s->zero_exc_pf) *
s->history_nsamples);
350 memset(
s->denoise_filter_cache, 0,
sizeof(
s->denoise_filter_cache));
351 }
352 }
353
354 /**
355 * Set up decoder with parameters from demuxer (extradata etc.).
356 */
358 {
360 int n,
flags, pitch_range, lsp16_flag,
ret;
362
364
365 /**
366 * Extradata layout:
367 * - byte 0-18: WMAPro-in-WMAVoice extradata (see wmaprodec.c),
368 * - byte 19-22: flags field (annoyingly in LE; see below for known
369 * values),
370 * - byte 23-46: variable bitmode tree (really just 17 * 3 bits,
371 * rest is 0).
372 */
373 if (
ctx->extradata_size != 46) {
375 "Invalid extradata size %d (should be 46)\n",
376 ctx->extradata_size);
378 }
379 if (
ctx->block_align <= 0 ||
ctx->block_align > (1<<22)) {
382 }
383
389
393
397
398 scale = 1.0 / (1 << 6);
402
403 scale = 1.0 / (1 << 6);
407
409 memcpy(&
s->sin[255],
s->cos, 256 *
sizeof(
s->cos[0]));
410 for (n = 0; n < 255; n++) {
411 s->sin[n] = -
s->sin[510 - n];
412 s->cos[510 - n] =
s->cos[n];
413 }
414 }
415 s->denoise_strength = (
flags >> 2) & 0xF;
416 if (
s->denoise_strength >= 12) {
418 "Invalid denoise filter strength %d (max=11)\n",
419 s->denoise_strength);
421 }
422 s->denoise_tilt_corr = !!(
flags & 0x40);
423 s->dc_level = (
flags >> 7) & 0xF;
424 s->lsp_q_mode = !!(
flags & 0x2000);
425 s->lsp_def_mode = !!(
flags & 0x4000);
426 lsp16_flag =
flags & 0x1000;
427 if (lsp16_flag) {
429 } else {
431 }
432 for (n = 0; n <
s->lsps; n++)
433 s->prev_lsps[n] =
M_PI * (n + 1.0) / (
s->lsps + 1.0);
434
439 }
440
441 if (
ctx->sample_rate >= INT_MAX / (256 * 37))
443
444 s->min_pitch_val = ((
ctx->sample_rate << 8) / 400 + 50) >> 8;
445 s->max_pitch_val = ((
ctx->sample_rate << 8) * 37 / 2000 + 50) >> 8;
446 pitch_range =
s->max_pitch_val -
s->min_pitch_val;
447 if (pitch_range <= 0) {
450 }
452 s->last_pitch_val = 40;
454 s->history_nsamples =
s->max_pitch_val + 8;
455
457 int min_sr = ((((1 << 8) - 50) * 400) + 0xFF) >> 8,
459
461 "Unsupported samplerate %d (min=%d, max=%d)\n",
462 ctx->sample_rate, min_sr, max_sr);
// 322-22097 Hz
463
465 }
466
467 s->block_conv_table[0] =
s->min_pitch_val;
468 s->block_conv_table[1] = (pitch_range * 25) >> 6;
469 s->block_conv_table[2] = (pitch_range * 44) >> 6;
470 s->block_conv_table[3] =
s->max_pitch_val - 1;
471 s->block_delta_pitch_hrange = (pitch_range >> 3) & ~0xF;
472 if (
s->block_delta_pitch_hrange <= 0) {
475 }
476 s->block_delta_pitch_nbits = 1 +
av_ceil_log2(
s->block_delta_pitch_hrange);
477 s->block_pitch_range =
s->block_conv_table[2] +
478 s->block_conv_table[3] + 1 +
479 2 * (
s->block_conv_table[1] - 2 *
s->min_pitch_val);
481
485
486 return 0;
487 }
488
489 /**
490 * @name Postfilter functions
491 * Postfilter functions (gain control, wiener denoise filter, DC filter,
492 * kalman smoothening, plus surrounding code to wrap it)
493 * @{
494 */
495 /**
496 * Adaptive gain control (as used in postfilter).
497 *
498 * Identical to #ff_adaptive_gain_control() in acelp_vectors.c, except
499 * that the energy here is calculated using sum(abs(...)), whereas the
500 * other codecs (e.g. AMR-NB, SIPRO) use sqrt(dotproduct(...)).
501 *
502 * @param out output buffer for filtered samples
503 * @param in input buffer containing the samples as they are after the
504 * postfilter steps so far
505 * @param speech_synth input buffer containing speech synth before postfilter
506 * @param size input buffer size
507 * @param alpha exponential filter factor
508 * @param gain_mem pointer to filter memory (single float)
509 */
511 const float *speech_synth,
513 {
515 float speech_energy = 0.0, postfilter_energy = 0.0, gain_scale_factor;
516 float mem = *gain_mem;
517
519 speech_energy +=
fabsf(speech_synth[
i]);
520 postfilter_energy +=
fabsf(in[
i]);
521 }
522 gain_scale_factor = postfilter_energy == 0.0 ? 0.0 :
523 (1.0 -
alpha) * speech_energy / postfilter_energy;
524
526 mem =
alpha * mem + gain_scale_factor;
527 out[
i] = in[
i] * mem;
528 }
529
530 *gain_mem = mem;
531 }
532
533 /**
534 * Kalman smoothing function.
535 *
536 * This function looks back pitch +/- 3 samples back into history to find
537 * the best fitting curve (that one giving the optimal gain of the two
538 * signals, i.e. the highest dot product between the two), and then
539 * uses that signal history to smoothen the output of the speech synthesis
540 * filter.
541 *
542 * @param s WMA Voice decoding context
543 * @param pitch pitch of the speech signal
544 * @param in input speech signal
545 * @param out output pointer for smoothened signal
546 * @param size input/output buffer size
547 *
548 * @returns -1 if no smoothening took place, e.g. because no optimal
549 * fit could be found, or 0 on success.
550 */
552 const float *in,
float *
out,
int size)
553 {
554 int n;
555 float optimal_gain = 0, dot;
556 const float *ptr = &in[-
FFMAX(
s->min_pitch_val, pitch - 3)],
557 *end = &in[-
FFMIN(
s->max_pitch_val, pitch + 3)],
558 *best_hist_ptr =
NULL;
559
560 /* find best fitting point in history */
561 do {
563 if (dot > optimal_gain) {
564 optimal_gain = dot;
565 best_hist_ptr = ptr;
566 }
567 } while (--ptr >= end);
568
569 if (optimal_gain <= 0)
570 return -1;
572 if (dot <= 0) // would be 1.0
573 return -1;
574
575 if (optimal_gain <= dot) {
576 dot = dot / (dot + 0.6 * optimal_gain); // 0.625-1.000
577 } else
578 dot = 0.625;
579
580 /* actual smoothing */
581 for (n = 0; n <
size; n++)
582 out[n] = best_hist_ptr[n] + dot * (in[n] - best_hist_ptr[n]);
583
584 return 0;
585 }
586
587 /**
588 * Get the tilt factor of a formant filter from its transfer function
589 * @see #tilt_factor() in amrnbdec.c, which does essentially the same,
590 * but somehow (??) it does a speech synthesis filter in the
591 * middle, which is missing here
592 *
593 * @param lpcs LPC coefficients
594 * @param n_lpcs Size of LPC buffer
595 * @returns the tilt factor
596 */
598 {
599 float rh0, rh1;
600
603
604 return rh1 / rh0;
605 }
606
607 /**
608 * Derive denoise filter coefficients (in real domain) from the LPCs.
609 */
611 int fcb_type, float *coeffs_dst, int remainder)
612 {
614 float irange, angle_mul, gain_mul,
range, sq;
618 int n, idx;
619
620 memcpy(coeffs, coeffs_dst, 0x82*sizeof(float));
621
622 /* Create frequency power spectrum of speech input (i.e. RDFT of LPCs) */
623 s->rdft_fn(
s->rdft, lpcs, lpcs_src,
sizeof(
float));
624 #define log_range(var, assign) do { \
625 float tmp = log10f(assign); var = tmp; \
626 max = FFMAX(max, tmp); min = FFMIN(min, tmp); \
627 } while (0)
629 for (n = 1; n < 64; n++)
630 log_range(lpcs[n], lpcs[n * 2] * lpcs[n * 2] +
631 lpcs[n * 2 + 1] * lpcs[n * 2 + 1]);
633 #undef log_range
636
637 /* Now, use this spectrum to pick out these frequencies with higher
638 * (relative) power/energy (which we then take to be "not noise"),
639 * and set up a table (still in lpc[]) of (relative) gains per frequency.
640 * These frequencies will be maintained, while others ("noise") will be
641 * decreased in the filter output. */
642 irange = 64.0 /
range;
// so irange*(max-value) is in the range [0, 63]
644 (5.0 / 14.7));
646 for (n = 0; n <= 64; n++) {
647 float pwr;
648
649 idx =
lrint((
max - lpcs[n]) * irange - 1);
652 lpcs[n] = angle_mul * pwr;
653
654 /* 70.57 =~ 1/log10(1.0331663) */
655 idx =
av_clipd((pwr * gain_mul - 0.0295) * 70.570526123, 0, INT_MAX / 2);
656
657 if (idx > 127) { // fall back if index falls outside table range
659 powf(1.0331663, idx - 127);
660 } else
662 }
663
664 /* calculate the Hilbert transform of the gains, which we do (since this
665 * is a sine input) by doing a phase shift (in theory, H(sin())=cos()).
666 * Hilbert_Transform(RDFT(x)) = Laplace_Transform(x), which calculates the
667 * "moment" of the LPCs in this filter. */
668 s->dct_fn(
s->dct, lpcs_dct, lpcs,
sizeof(
float));
669 s->dst_fn(
s->dst, lpcs, lpcs_dct,
sizeof(
float));
670
671 /* Split out the coefficient indexes into phase/magnitude pairs */
672 idx = 255 +
av_clip(lpcs[64], -255, 255);
673 coeffs[0] = coeffs[0] *
s->cos[idx];
674 idx = 255 +
av_clip(lpcs[64] - 2 * lpcs[63], -255, 255);
676 for (n = 63;; n--) {
677 idx = 255 +
av_clip(-lpcs[64] - 2 * lpcs[n - 1], -255, 255);
678 coeffs[n * 2 + 1] = coeffs[n] *
s->sin[idx];
679 coeffs[n * 2] = coeffs[n] *
s->cos[idx];
680
681 if (!--n) break;
682
683 idx = 255 +
av_clip( lpcs[64] - 2 * lpcs[n - 1], -255, 255);
684 coeffs[n * 2 + 1] = coeffs[n] *
s->sin[idx];
685 coeffs[n * 2] = coeffs[n] *
s->cos[idx];
686 }
688
689 /* move into real domain */
691
692 /* tilt correction and normalize scale */
693 memset(&coeffs_dst[remainder], 0, sizeof(coeffs_dst[0]) * (128 - remainder));
694 if (
s->denoise_tilt_corr) {
695 float tilt_mem = 0;
696
697 coeffs_dst[remainder - 1] = 0;
700 coeffs_dst, remainder);
701 }
703 remainder));
704 for (n = 0; n < remainder; n++)
705 coeffs_dst[n] *= sq;
706 }
707
708 /**
709 * This function applies a Wiener filter on the (noisy) speech signal as
710 * a means to denoise it.
711 *
712 * - take RDFT of LPCs to get the power spectrum of the noise + speech;
713 * - using this power spectrum, calculate (for each frequency) the Wiener
714 * filter gain, which depends on the frequency power and desired level
715 * of noise subtraction (when set too high, this leads to artifacts)
716 * We can do this symmetrically over the X-axis (so 0-4kHz is the inverse
717 * of 4-8kHz);
718 * - by doing a phase shift, calculate the Hilbert transform of this array
719 * of per-frequency filter-gains to get the filtering coefficients;
720 * - smoothen/normalize/de-tilt these filter coefficients as desired;
721 * - take RDFT of noisy sound, apply the coefficients and take its IRDFT
722 * to get the denoised speech signal;
723 * - the leftover (i.e. output of the IRDFT on denoised speech data beyond
724 * the frame boundary) are saved and applied to subsequent frames by an
725 * overlap-add method (otherwise you get clicking-artifacts).
726 *
727 * @param s WMA Voice decoding context
728 * @param fcb_type Frame (codebook) type
729 * @param synth_pf input: the noisy speech signal, output: denoised speech
730 * data; should be 16-byte aligned (for ASM purposes)
731 * @param size size of the speech data
732 * @param lpcs LPCs used to synthesize this frame's speech data
733 */
735 float *synth_pf,
int size,
736 const float *lpcs)
737 {
738 int remainder, lim, n;
739
743 float *tilted_lpcs =
s->tilted_lpcs_pf,
744 *coeffs =
s->denoise_coeffs_pf, tilt_mem = 0;
745
746 tilted_lpcs[0] = 1.0;
747 memcpy(&tilted_lpcs[1], lpcs,
sizeof(lpcs[0]) *
s->lsps);
748 memset(&tilted_lpcs[
s->lsps + 1], 0,
749 sizeof(tilted_lpcs[0]) * (128 -
s->lsps - 1));
751 tilted_lpcs,
s->lsps + 2);
752
753 /* The IRDFT output (127 samples for 7-bit filter) beyond the frame
754 * size is applied to the next frame. All input beyond this is zero,
755 * and thus all output beyond this will go towards zero, hence we can
756 * limit to min(size-1, 127-size) as a performance consideration. */
759
760 /* apply coefficients (in frequency spectrum domain), i.e. complex
761 * number multiplication */
762 memset(&synth_pf[
size], 0,
sizeof(synth_pf[0]) * (128 -
size));
763 s->rdft_fn(
s->rdft, synth_f, synth_pf,
sizeof(
float));
764 s->rdft_fn(
s->rdft, coeffs_f, coeffs,
sizeof(
float));
765 synth_f[0] *= coeffs_f[0];
766 synth_f[1] *= coeffs_f[1];
767 for (n = 1; n <= 64; n++) {
768 float v1 = synth_f[n * 2], v2 = synth_f[n * 2 + 1];
769 synth_f[n * 2] = v1 * coeffs_f[n * 2] - v2 * coeffs_f[n * 2 + 1];
770 synth_f[n * 2 + 1] = v2 * coeffs_f[n * 2] + v1 * coeffs_f[n * 2 + 1];
771 }
773 }
774
775 /* merge filter output with the history of previous runs */
776 if (
s->denoise_filter_cache_size) {
777 lim =
FFMIN(
s->denoise_filter_cache_size,
size);
778 for (n = 0; n < lim; n++)
779 synth_pf[n] +=
s->denoise_filter_cache[n];
780 s->denoise_filter_cache_size -= lim;
781 memmove(
s->denoise_filter_cache, &
s->denoise_filter_cache[
size],
782 sizeof(
s->denoise_filter_cache[0]) *
s->denoise_filter_cache_size);
783 }
784
785 /* move remainder of filter output into a cache for future runs */
787 lim =
FFMIN(remainder,
s->denoise_filter_cache_size);
788 for (n = 0; n < lim; n++)
789 s->denoise_filter_cache[n] += synth_pf[
size + n];
790 if (lim < remainder) {
791 memcpy(&
s->denoise_filter_cache[lim], &synth_pf[
size + lim],
792 sizeof(
s->denoise_filter_cache[0]) * (remainder - lim));
793 s->denoise_filter_cache_size = remainder;
794 }
795 }
796 }
797
798 /**
799 * Averaging projection filter, the postfilter used in WMAVoice.
800 *
801 * This uses the following steps:
802 * - A zero-synthesis filter (generate excitation from synth signal)
803 * - Kalman smoothing on excitation, based on pitch
804 * - Re-synthesized smoothened output
805 * - Iterative Wiener denoise filter
806 * - Adaptive gain filter
807 * - DC filter
808 *
809 * @param s WMAVoice decoding context
810 * @param synth Speech synthesis output (before postfilter)
811 * @param samples Output buffer for filtered samples
812 * @param size Buffer size of synth & samples
813 * @param lpcs Generated LPCs used for speech synthesis
814 * @param zero_exc_pf destination for zero synthesis filter (16-byte aligned)
815 * @param fcb_type Frame type (silence, hardcoded, AW-pulses or FCB-pulses)
816 * @param pitch Pitch of the input signal
817 */
820 const float *lpcs, float *zero_exc_pf,
821 int fcb_type, int pitch)
822 {
825 *synth_filter_in = zero_exc_pf;
826
828
829 /* generate excitation from input signal */
831
834 synth_filter_in = synth_filter_in_buf;
835
836 /* re-synthesize speech after smoothening, and keep history */
838 synth_filter_in,
size,
s->lsps);
839 memcpy(&synth_pf[-
s->lsps], &synth_pf[
size -
s->lsps],
840 sizeof(synth_pf[0]) *
s->lsps);
841
843
846
847 if (
s->dc_level > 8) {
848 /* remove ultra-low frequency DC noise / highpass filter;
849 * coefficients are identical to those used in SIPR decoding,
850 * and very closely resemble those used in AMR-NB decoding. */
852 (const float[2]) { -1.99997, 1.0 },
853 (const float[2]) { -1.9330735188, 0.93589198496 },
854 0.93980580475,
s->dcf_mem,
size);
855 }
856 }
857 /**
858 * @}
859 */
860
861 /**
862 * Dequantize LSPs
863 * @param lsps output pointer to the array that will hold the LSPs
864 * @param num number of LSPs to be dequantized
865 * @param values quantized values, contains n_stages values
866 * @param sizes range (i.e. max value) of each quantized value
867 * @param n_stages number of dequantization runs
868 * @param table dequantization table to be used
869 * @param mul_q LSF multiplier
870 * @param base_q base (lowest) LSF values
871 */
874 const uint16_t *
sizes,
875 int n_stages,
const uint8_t *
table,
876 const double *mul_q,
877 const double *base_q)
878 {
879 int n, m;
880
881 memset(lsps, 0, num * sizeof(*lsps));
882 for (n = 0; n < n_stages; n++) {
884 double base = base_q[n], mul = mul_q[n];
885
886 for (m = 0; m < num; m++)
887 lsps[m] +=
base + mul * t_off[m];
888
890 }
891 }
892
893 /**
894 * @name LSP dequantization routines
895 * LSP dequantization routines, for 10/16LSPs and independent/residual coding.
896 * lsp10i() consumes 24 bits; lsp10r() consumes an additional 24 bits;
897 * lsp16i() consumes 34 bits; lsp16r() consumes an additional 26 bits.
898 * @{
899 */
900 /**
901 * Parse 10 independently-coded LSPs.
902 */
904 {
905 static const uint16_t vec_sizes[4] = { 256, 64, 32, 32 };
906 static const double mul_lsf[4] = {
907 5.2187144800e-3, 1.4626986422e-3,
908 9.6179549166e-4, 1.1325736225e-3
909 };
910 static const double base_lsf[4] = {
911 M_PI * -2.15522e-1,
M_PI * -6.1646e-2,
912 M_PI * -3.3486e-2,
M_PI * -5.7408e-2
913 };
914 uint16_t v[4];
915
920
922 mul_lsf, base_lsf);
923 }
924
925 /**
926 * Parse 10 independently-coded LSPs, and then derive the tables to
927 * generate LSPs for the other frames from them (residual coding).
928 */
930 double *i_lsps, const double *old,
931 double *
a1,
double *
a2,
int q_mode)
932 {
933 static const uint16_t vec_sizes[3] = { 128, 64, 64 };
934 static const double mul_lsf[3] = {
935 2.5807601174e-3, 1.2354460219e-3, 1.1763821673e-3
936 };
937 static const double base_lsf[3] = {
938 M_PI * -1.07448e-1,
M_PI * -5.2706e-2,
M_PI * -5.1634e-2
939 };
940 const float (*ipol_tab)[2][10] = q_mode ?
943 int n;
944
946
951
952 for (n = 0; n < 10; n++) {
953 double delta = old[n] - i_lsps[n];
956 }
957
959 mul_lsf, base_lsf);
960 }
961
962 /**
963 * Parse 16 independently-coded LSPs.
964 */
966 {
967 static const uint16_t vec_sizes[5] = { 256, 64, 128, 64, 128 };
968 static const double mul_lsf[5] = {
969 3.3439586280e-3, 6.9908173703e-4,
970 3.3216608306e-3, 1.0334960326e-3,
971 3.1899104283e-3
972 };
973 static const double base_lsf[5] = {
974 M_PI * -1.27576e-1,
M_PI * -2.4292e-2,
975 M_PI * -1.28094e-1,
M_PI * -3.2128e-2,
977 };
978 uint16_t v[5];
979
985
992 }
993
994 /**
995 * Parse 16 independently-coded LSPs, and then derive the tables to
996 * generate LSPs for the other frames from them (residual coding).
997 */
999 double *i_lsps, const double *old,
1000 double *
a1,
double *
a2,
int q_mode)
1001 {
1002 static const uint16_t vec_sizes[3] = { 128, 128, 128 };
1003 static const double mul_lsf[3] = {
1004 1.2232979501e-3, 1.4062241527e-3, 1.6114744851e-3
1005 };
1006 static const double base_lsf[3] = {
1007 M_PI * -5.5830e-2,
M_PI * -5.2908e-2,
M_PI * -5.4776e-2
1008 };
1009 const float (*ipol_tab)[2][16] = q_mode ?
1012 int n;
1013
1015
1020
1021 for (n = 0; n < 16; n++) {
1022 double delta = old[n] - i_lsps[n];
1025 }
1026
1033 }
1034
1035 /**
1036 * @}
1037 * @name Pitch-adaptive window coding functions
1038 * The next few functions are for pitch-adaptive window coding.
1039 * @{
1040 */
1041 /**
1042 * Parse the offset of the first pitch-adaptive window pulses, and
1043 * the distribution of pulses between the two blocks in this frame.
1044 * @param s WMA Voice decoding context private data
1045 * @param gb bit I/O context
1046 * @param pitch pitch for each block in this frame
1047 */
1049 const int *pitch)
1050 {
1051 static const int16_t start_offset[94] = {
1052 -11, -9, -7, -5, -3, -1, 1, 3, 5, 7, 9, 11,
1053 13, 15, 18, 17, 19, 20, 21, 22, 23, 24, 25, 26,
1054 27, 28, 29, 30, 31, 32, 33, 35, 37, 39, 41, 43,
1055 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67,
1056 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91,
1057 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115,
1058 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139,
1059 141, 143, 145, 147, 149, 151, 153, 155, 157, 159
1060 };
1062
1063 /* position of pulse */
1064 s->aw_idx_is_ext = 0;
1066 s->aw_idx_is_ext = 1;
1068 }
1069
1070 /* for a repeated pulse at pulse_off with a pitch_lag of pitch[], count
1071 * the distribution of the pulses in each block contained in this frame. */
1072 s->aw_pulse_range =
FFMIN(pitch[0], pitch[1]) > 32 ? 24 : 16;
1075 s->aw_first_pulse_off[0] =
offset -
s->aw_pulse_range / 2;
1076 offset +=
s->aw_n_pulses[0] * pitch[0];
1079
1080 /* if continuing from a position before the block, reset position to
1081 * start of block (when corrected for the range over which it can be
1082 * spread in aw_pulse_set1()). */
1084 while (
s->aw_first_pulse_off[1] - pitch[1] +
s->aw_pulse_range > 0)
1085 s->aw_first_pulse_off[1] -= pitch[1];
1086 if (start_offset[
bits] < 0)
1087 while (
s->aw_first_pulse_off[0] - pitch[0] +
s->aw_pulse_range > 0)
1088 s->aw_first_pulse_off[0] -= pitch[0];
1089 }
1090 }
1091
1092 /**
1093 * Apply second set of pitch-adaptive window pulses.
1094 * @param s WMA Voice decoding context private data
1095 * @param gb bit I/O context
1096 * @param block_idx block index in frame [0, 1]
1097 * @param fcb structure containing fixed codebook vector info
1098 * @return -1 on error, 0 otherwise
1099 */
1102 {
1103 uint16_t use_mask_mem[9]; // only 5 are used, rest is padding
1104 uint16_t *use_mask = use_mask_mem + 2;
1105 /* in this function, idx is the index in the 80-bit (+ padding) use_mask
1106 * bit-array. Since use_mask consists of 16-bit values, the lower 4 bits
1107 * of idx are the position of the bit within a particular item in the
1108 * array (0 being the most significant bit, and 15 being the least
1109 * significant bit), and the remainder (>> 4) is the index in the
1110 * use_mask[]-array. This is faster and uses less memory than using a
1111 * 80-byte/80-int array. */
1112 int pulse_off =
s->aw_first_pulse_off[block_idx],
1113 pulse_start, n, idx,
range, aidx, start_off = 0;
1114
1115 /* set offset of first pulse to within this block */
1116 if (
s->aw_n_pulses[block_idx] > 0)
1117 while (pulse_off +
s->aw_pulse_range < 1)
1119
1120 /* find range per pulse */
1121 if (
s->aw_n_pulses[0] > 0) {
1122 if (block_idx == 0) {
1124 } else /* block_idx = 1 */ {
1126 if (
s->aw_n_pulses[block_idx] > 0)
1127 pulse_off =
s->aw_next_pulse_off_cache;
1128 }
1129 } else
1131 pulse_start =
s->aw_n_pulses[block_idx] > 0 ? pulse_off -
range / 2 : 0;
1132
1133 /* aw_pulse_set1() already applies pulses around pulse_off (to be exactly,
1134 * in the range of [pulse_off, pulse_off + s->aw_pulse_range], and thus
1135 * we exclude that range from being pulsed again in this function. */
1136 memset(&use_mask[-2], 0, 2 * sizeof(use_mask[0]));
1137 memset( use_mask, -1, 5 * sizeof(use_mask[0]));
1138 memset(&use_mask[5], 0, 2 * sizeof(use_mask[0]));
1139 if (
s->aw_n_pulses[block_idx] > 0)
1141 int excl_range =
s->aw_pulse_range;
// always 16 or 24
1142 uint16_t *use_mask_ptr = &use_mask[idx >> 4];
1143 int first_sh = 16 - (idx & 15);
1144 *use_mask_ptr++ &= 0xFFFF
u << first_sh;
1145 excl_range -= first_sh;
1146 if (excl_range >= 16) {
1147 *use_mask_ptr++ = 0;
1148 *use_mask_ptr &= 0xFFFF >> (excl_range - 16);
1149 } else
1150 *use_mask_ptr &= 0xFFFF >> excl_range;
1151 }
1152
1153 /* find the 'aidx'th offset that is not excluded */
1154 aidx =
get_bits(gb,
s->aw_n_pulses[0] > 0 ? 5 - 2 * block_idx : 4);
1155 for (n = 0; n <= aidx; pulse_start++) {
1156 for (idx = pulse_start; idx < 0; idx += fcb->
pitch_lag) ;
1158 if (use_mask[0]) idx = 0x0F;
1159 else if (use_mask[1]) idx = 0x1F;
1160 else if (use_mask[2]) idx = 0x2F;
1161 else if (use_mask[3]) idx = 0x3F;
1162 else if (use_mask[4]) idx = 0x4F;
1163 else return -1;
1165 }
1166 if (use_mask[idx >> 4] & (0x8000 >> (idx & 15))) {
1167 use_mask[idx >> 4] &= ~(0x8000 >> (idx & 15));
1168 n++;
1169 start_off = idx;
1170 }
1171 }
1172
1173 fcb->
x[fcb->
n] = start_off;
1176
1177 /* set offset for next block, relative to start of that block */
1179 s->aw_next_pulse_off_cache = n ? fcb->
pitch_lag - n : 0;
1180 return 0;
1181 }
1182
1183 /**
1184 * Apply first set of pitch-adaptive window pulses.
1185 * @param s WMA Voice decoding context private data
1186 * @param gb bit I/O context
1187 * @param block_idx block index in frame [0, 1]
1188 * @param fcb storage location for fixed codebook pulse info
1189 */
1192 {
1193 int val =
get_bits(gb, 12 - 2 * (
s->aw_idx_is_ext && !block_idx));
1194 float v;
1195
1196 if (
s->aw_n_pulses[block_idx] > 0) {
1197 int n, v_mask, i_mask, sh, n_pulses;
1198
1199 if (
s->aw_pulse_range == 24) {
// 3 pulses, 1:sign + 3:index each
1200 n_pulses = 3;
1201 v_mask = 8;
1202 i_mask = 7;
1203 sh = 4;
1204 } else { // 4 pulses, 1:sign + 2:index each
1205 n_pulses = 4;
1206 v_mask = 4;
1207 i_mask = 3;
1208 sh = 3;
1209 }
1210
1211 for (n = n_pulses - 1; n >= 0; n--,
val >>= sh) {
1212 fcb->
y[fcb->
n] = (
val & v_mask) ? -1.0 : 1.0;
1213 fcb->
x[fcb->
n] = (
val & i_mask) * n_pulses + n +
1214 s->aw_first_pulse_off[block_idx];
1215 while (fcb->
x[fcb->
n] < 0)
1219 }
1220 } else {
1221 int num2 = (
val & 0x1FF) >> 1,
delta, idx;
1222
1223 if (num2 < 1 * 79) {
delta = 1; idx = num2 + 1; }
1224 else if (num2 < 2 * 78) {
delta = 3; idx = num2 + 1 - 1 * 77; }
1225 else if (num2 < 3 * 77) {
delta = 5; idx = num2 + 1 - 2 * 76; }
1226 else {
delta = 7; idx = num2 + 1 - 3 * 75; }
1227 v = (
val & 0x200) ? -1.0 : 1.0;
1228
1232 fcb->
x[fcb->
n + 1] = idx;
1233 fcb->
y[fcb->
n + 1] = (
val & 1) ? -v : v;
1235 }
1236 }
1237
1238 /**
1239 * @}
1240 *
1241 * Generate a random number from frame_cntr and block_idx, which will live
1242 * in the range [0, 1000 - block_size] (so it can be used as an index in a
1243 * table of size 1000 of which you want to read block_size entries).
1244 *
1245 * @param frame_cntr current frame number
1246 * @param block_num current block index
1247 * @param block_size amount of entries we want to read from a table
1248 * that has 1000 entries
1249 * @return a (non-)random number in the [0, 1000 - block_size] range.
1250 */
1251 static int pRNG(
int frame_cntr,
int block_num,
int block_size)
1252 {
1253 /* array to simplify the calculation of z:
1254 * y = (x % 9) * 5 + 6;
1255 * z = (49995 * x) / y;
1256 * Since y only has 9 values, we can remove the division by using a
1257 * LUT and using FASTDIV-style divisions. For each of the 9 values
1258 * of y, we can rewrite z as:
1259 * z = x * (49995 / y) + x * ((49995 % y) / y)
1260 * In this table, each col represents one possible value of y, the
1261 * first number is 49995 / y, and the second is the FASTDIV variant
1262 * of 49995 % y / y. */
1263 static const unsigned int div_tbl[9][2] = {
1264 { 8332, 3 * 715827883
U },
// y = 6
1265 { 4545, 0 * 390451573
U },
// y = 11
1266 { 3124, 11 * 268435456
U },
// y = 16
1267 { 2380, 15 * 204522253
U },
// y = 21
1268 { 1922, 23 * 165191050
U },
// y = 26
1269 { 1612, 23 * 138547333
U },
// y = 31
1270 { 1388, 27 * 119304648
U },
// y = 36
1271 { 1219, 16 * 104755300
U },
// y = 41
1272 { 1086, 39 * 93368855
U }
// y = 46
1273 };
1274 unsigned int z, y, x =
MUL16(block_num, 1877) + frame_cntr;
1275 if (x >= 0xFFFF) x -= 0xFFFF; // max value of x is 8*1877+0xFFFE=0x13AA6,
1276 // so this is effectively a modulo (%)
1277 y = x - 9 *
MULH(477218589, x);
// x % 9
1278 z = (uint16_t) (x * div_tbl[y][0] +
UMULH(x, div_tbl[y][1]));
1279 // z = x * 49995 / (y * 5 + 6)
1280 return z % (1000 - block_size);
1281 }
1282
1283 /**
1284 * Parse hardcoded signal for a single block.
1285 * @note see #synth_block().
1286 */
1288 int block_idx,
int size,
1290 float *excitation)
1291 {
1292 float gain;
1293 int n, r_idx;
1294
1296
1297 /* Set the offset from which we start reading wmavoice_std_codebook */
1299 r_idx =
pRNG(
s->frame_cntr, block_idx,
size);
1300 gain =
s->silence_gain;
1301 } else /* FCB_TYPE_HARDCODED */ {
1304 }
1305
1306 /* Clear gain prediction parameters */
1307 memset(
s->gain_pred_err, 0,
sizeof(
s->gain_pred_err));
1308
1309 /* Apply gain to hardcoded codebook and use that as excitation signal */
1310 for (n = 0; n <
size; n++)
1312 }
1313
1314 /**
1315 * Parse FCB/ACB signal for a single block.
1316 * @note see #synth_block().
1317 */
1319 int block_idx,
int size,
1320 int block_pitch_sh2,
1322 float *excitation)
1323 {
1324 static const float gain_coeff[6] = {
1325 0.8169, -0.06545, 0.1726, 0.0185, -0.0359, 0.0458
1326 };
1328 int n, idx, gain_weight;
1330
1333
1338
1339 /* For the other frame types, this is where we apply the innovation
1340 * (fixed) codebook pulses of the speech signal. */
1344 /* Conceal the block with silence and return.
1345 * Skip the correct amount of bits to read the next
1346 * block from the correct offset. */
1347 int r_idx =
pRNG(
s->frame_cntr, block_idx,
size);
1348
1349 for (n = 0; n <
size; n++)
1350 excitation[n] =
1353 return;
1354 }
1355 } else /* FCB_TYPE_EXC_PULSES */ {
1357
1359 /* similar to ff_decode_10_pulses_35bits(), but with single pulses
1360 * (instead of double) for a subset of pulses */
1361 for (n = 0; n < 5; n++) {
1362 float sign;
1363 int pos1, pos2;
1364
1367 fcb.
x[fcb.
n] = n + 5 * pos1;
1368 fcb.
y[fcb.
n++] = sign;
1369 if (n < frame_desc->dbl_pulses) {
1371 fcb.
x[fcb.
n] = n + 5 * pos2;
1372 fcb.
y[fcb.
n++] = (pos1 < pos2) ? -sign : sign;
1373 }
1374 }
1375 }
1377
1378 /* Calculate gain for adaptive & fixed codebook signal.
1379 * see ff_amr_set_fixed_gain(). */
1382 gain_coeff, 6) -
1386 -2.9957322736 /* log(0.05) */,
1387 1.6094379124 /* log(5.0) */);
1388
1390 memmove(&
s->gain_pred_err[gain_weight],
s->gain_pred_err,
1391 sizeof(*
s->gain_pred_err) * (6 - gain_weight));
1392 for (n = 0; n < gain_weight; n++)
1393 s->gain_pred_err[n] = pred_err;
1394
1395 /* Calculation of adaptive codebook */
1398 for (n = 0; n <
size; n +=
len) {
1399 int next_idx_sh16;
1400 int abs_idx = block_idx *
size + n;
1401 int pitch_sh16 = (
s->last_pitch_val << 16) +
1402 s->pitch_diff_sh16 * abs_idx;
1403 int pitch = (pitch_sh16 + 0x6FFF) >> 16;
1404 int idx_sh16 = ((pitch << 16) - pitch_sh16) * 8 + 0x58000;
1405 idx = idx_sh16 >> 16;
1406 if (
s->pitch_diff_sh16) {
1407 if (
s->pitch_diff_sh16 > 0) {
1408 next_idx_sh16 = (idx_sh16) &~ 0xFFFF;
1409 } else
1410 next_idx_sh16 = (idx_sh16 + 0x10000) &~ 0xFFFF;
1411 len =
av_clip((idx_sh16 - next_idx_sh16) /
s->pitch_diff_sh16 / 8,
1413 } else
1415
1419 }
1420 } else /* ACB_TYPE_HAMMING */ {
1421 int block_pitch = block_pitch_sh2 >> 2;
1422 idx = block_pitch_sh2 & 3;
1423 if (idx) {
1427 } else
1429 sizeof(
float) *
size);
1430 }
1431
1432 /* Interpolate ACB/FCB and use as excitation signal */
1434 acb_gain, fcb_gain,
size);
1435 }
1436
1437 /**
1438 * Parse data in a single block.
1439 *
1440 * @param s WMA Voice decoding context private data
1441 * @param gb bit I/O context
1442 * @param block_idx index of the to-be-read block
1443 * @param size amount of samples to be read in this block
1444 * @param block_pitch_sh2 pitch for this block << 2
1445 * @param lsps LSPs for (the end of) this frame
1446 * @param prev_lsps LSPs for the last frame
1447 * @param frame_desc frame type descriptor
1448 * @param excitation target memory for the ACB+FCB interpolated signal
1449 * @param synth target memory for the speech synthesis filter output
1450 * @return 0 on success, <0 on error.
1451 */
1453 int block_idx,
int size,
1454 int block_pitch_sh2,
1455 const double *lsps, const double *prev_lsps,
1457 float *excitation, float *synth)
1458 {
1461 float fac;
1462 int n;
1463
1466 else
1468 frame_desc, excitation);
1469
1470 /* convert interpolated LSPs to LPCs */
1471 fac = (block_idx + 0.5) / frame_desc->
n_blocks;
1472 for (n = 0; n <
s->lsps; n++)
// LSF -> LSP
1473 i_lsps[n] = cos(prev_lsps[n] + fac * (lsps[n] - prev_lsps[n]));
1475
1476 /* Speech synthesis */
1478 }
1479
1480 /**
1481 * Synthesize output samples for a single frame.
1482 *
1483 * @param ctx WMA Voice decoder context
1484 * @param gb bit I/O context (s->gb or one for cross-packet superframes)
1485 * @param frame_idx Frame number within superframe [0-2]
1486 * @param samples pointer to output sample buffer, has space for at least 160
1487 * samples
1488 * @param lsps LSP array
1489 * @param prev_lsps array of previous frame's LSPs
1490 * @param excitation target buffer for excitation signal
1491 * @param synth target buffer for synthesized speech data
1492 * @return 0 on success, <0 on error.
1493 */
1496 const double *lsps, const double *prev_lsps,
1497 float *excitation, float *synth)
1498 {
1500 int n, n_blocks_x2, log_n_blocks_x2,
av_uninit(cur_pitch_val);
1502
1503 /* Parse frame type ("frame header"), see frame_descs */
1505
1506 pitch[0] = INT_MAX;
1507
1508 if (bd_idx < 0) {
1510 "Invalid frame type VLC code, skipping\n");
1512 }
1513
1515
1516 /* Pitch calculation for ACB_TYPE_ASYMMETRIC ("pitch-per-frame") */
1518 /* Pitch is provided per frame, which is interpreted as the pitch of
1519 * the last sample of the last block of this frame. We can interpolate
1520 * the pitch of other blocks (and even pitch-per-sample) by gradually
1521 * incrementing/decrementing prev_frame_pitch to cur_pitch_val. */
1524 cur_pitch_val =
s->min_pitch_val +
get_bits(gb,
s->pitch_nbits);
1525 cur_pitch_val =
FFMIN(cur_pitch_val,
s->max_pitch_val - 1);
1527 20 *
abs(cur_pitch_val -
s->last_pitch_val) >
1528 (cur_pitch_val +
s->last_pitch_val))
1529 s->last_pitch_val = cur_pitch_val;
1530
1531 /* pitch per block */
1533 int fac = n * 2 + 1;
1534
1535 pitch[n] = (
MUL16(fac, cur_pitch_val) +
1536 MUL16((n_blocks_x2 - fac),
s->last_pitch_val) +
1538 }
1539
1540 /* "pitch-diff-per-sample" for calculation of pitch per sample */
1541 s->pitch_diff_sh16 =
1543 }
1544
1545 /* Global gain (if silence) and pitch-adaptive window coordinates */
1549 break;
1552 break;
1553 }
1554
1556 int bl_pitch_sh2;
1557
1558 /* Pitch calculation for ACB_TYPE_HAMMING ("pitch-per-block") */
1561 /* Pitch is given per block. Per-block pitches are encoded as an
1562 * absolute value for the first block, and then delta values
1563 * relative to this value) for all subsequent blocks. The scale of
1564 * this pitch value is semi-logarithmic compared to its use in the
1565 * decoder, so we convert it to normal scale also. */
1566 int block_pitch,
1567 t1 = (
s->block_conv_table[1] -
s->block_conv_table[0]) << 2,
1568 t2 = (
s->block_conv_table[2] -
s->block_conv_table[1]) << 1,
1569 t3 =
s->block_conv_table[3] -
s->block_conv_table[2] + 1;
1570
1571 if (n == 0) {
1572 block_pitch =
get_bits(gb,
s->block_pitch_nbits);
1573 } else
1574 block_pitch = last_block_pitch -
s->block_delta_pitch_hrange +
1575 get_bits(gb,
s->block_delta_pitch_nbits);
1576 /* Convert last_ so that any next delta is within _range */
1577 last_block_pitch =
av_clip(block_pitch,
1578 s->block_delta_pitch_hrange,
1579 s->block_pitch_range -
1580 s->block_delta_pitch_hrange);
1581
1582 /* Convert semi-log-style scale back to normal scale */
1583 if (block_pitch < t1) {
1584 bl_pitch_sh2 = (
s->block_conv_table[0] << 2) + block_pitch;
1585 } else {
1586 block_pitch -= t1;
1587 if (block_pitch < t2) {
1588 bl_pitch_sh2 =
1589 (
s->block_conv_table[1] << 2) + (block_pitch << 1);
1590 } else {
1591 block_pitch -= t2;
1592 if (block_pitch < t3) {
1593 bl_pitch_sh2 =
1594 (
s->block_conv_table[2] + block_pitch) << 2;
1595 } else
1596 bl_pitch_sh2 =
s->block_conv_table[3] << 2;
1597 }
1598 }
1599 pitch[n] = bl_pitch_sh2 >> 2;
1600 break;
1601 }
1602
1604 bl_pitch_sh2 = pitch[n] << 2;
1605 break;
1606 }
1607
1608 default: // ACB_TYPE_NONE has no pitch
1609 bl_pitch_sh2 = 0;
1610 break;
1611 }
1612
1615 &excitation[n * block_nsamples],
1616 &synth[n * block_nsamples]);
1617 }
1618
1619 /* Averaging projection filter, if applicable. Else, just copy samples
1620 * from synthesis buffer */
1624
1627
1628 for (n = 0; n <
s->lsps; n++)
// LSF -> LSP
1629 i_lsps[n] = cos(0.5 * (prev_lsps[n] + lsps[n]));
1634
1635 for (n = 0; n <
s->lsps; n++)
// LSF -> LSP
1636 i_lsps[n] = cos(lsps[n]);
1639 &
s->zero_exc_pf[
s->history_nsamples +
MAX_FRAMESIZE * frame_idx + 80],
1641 } else
1642 memcpy(
samples, synth, 160 *
sizeof(synth[0]));
1643
1644 /* Cache values for next frame */
1646 if (
s->frame_cntr >= 0xFFFF)
s->frame_cntr -= 0xFFFF;
// i.e. modulo (%)
1650 s->last_pitch_val = 0;
1651 break;
1653 s->last_pitch_val = cur_pitch_val;
1654 break;
1657 break;
1658 }
1659
1660 return 0;
1661 }
1662
1663 /**
1664 * Ensure minimum value for first item, maximum value for last value,
1665 * proper spacing between each value and proper ordering.
1666 *
1667 * @param lsps array of LSPs
1668 * @param num size of LSP array
1669 *
1670 * @note basically a double version of #ff_acelp_reorder_lsf(), might be
1671 * useful to put in a generic location later on. Parts are also
1672 * present in #ff_set_min_dist_lsf() + #ff_sort_nearly_sorted_floats(),
1673 * which is in float.
1674 */
1676 {
1677 int n, m, l;
1678
1679 /* set minimum value for first, maximum value for last and minimum
1680 * spacing between LSF values.
1681 * Very similar to ff_set_min_dist_lsf(), but in double. */
1682 lsps[0] =
FFMAX(lsps[0], 0.0015 *
M_PI);
1683 for (n = 1; n < num; n++)
1684 lsps[n] =
FFMAX(lsps[n], lsps[n - 1] + 0.0125 *
M_PI);
1685 lsps[num - 1] =
FFMIN(lsps[num - 1], 0.9985 *
M_PI);
1686
1687 /* reorder (looks like one-time / non-recursed bubblesort).
1688 * Very similar to ff_sort_nearly_sorted_floats(), but in double. */
1689 for (n = 1; n < num; n++) {
1690 if (lsps[n] < lsps[n - 1]) {
1691 for (m = 1; m < num; m++) {
1692 double tmp = lsps[m];
1693 for (l = m - 1; l >= 0; l--) {
1694 if (lsps[l] <=
tmp)
break;
1695 lsps[l + 1] = lsps[l];
1696 }
1698 }
1699 break;
1700 }
1701 }
1702 }
1703
1704 /**
1705 * Synthesize output samples for a single superframe. If we have any data
1706 * cached in s->sframe_cache, that will be used instead of whatever is loaded
1707 * in s->gb.
1708 *
1709 * WMA Voice superframes contain 3 frames, each containing 160 audio samples,
1710 * to give a total of 480 samples per frame. See #synth_frame() for frame
1711 * parsing. In addition to 3 frames, superframes can also contain the LSPs
1712 * (if these are globally specified for all frames (residually); they can
1713 * also be specified individually per-frame. See the s->has_residual_lsps
1714 * option), and can specify the number of samples encoded in this superframe
1715 * (if less than 480), usually used to prevent blanks at track boundaries.
1716 *
1717 * @param ctx WMA Voice decoder context
1718 * @return 0 on success, <0 on error or 1 if there was not enough data to
1719 * fully parse the superframe
1720 */
1722 int *got_frame_ptr)
1723 {
1728 const double *
mean_lsf =
s->lsps == 16 ?
1733
1734 memcpy(synth,
s->synth_history,
1735 s->lsps *
sizeof(*synth));
1736 memcpy(excitation,
s->excitation_history,
1737 s->history_nsamples *
sizeof(*excitation));
1738
1739 if (
s->sframe_cache_size > 0) {
1740 gb = &s_gb;
1742 s->sframe_cache_size = 0;
1743 }
1744
1745 /* First bit is speech/music bit, it differentiates between WMAVoice
1746 * speech samples (the actual codec) and WMAVoice music samples, which
1747 * are really WMAPro-in-WMAVoice-superframes. I've never seen those in
1748 * the wild yet. */
1752 }
1753
1754 /* (optional) nr. of samples in superframe; always <= 480 and >= 0 */
1758 "Superframe encodes > %d samples (%d), not allowed\n",
1761 }
1762 }
1763
1764 /* Parse LSPs, if global for the superframe (can also be per-frame). */
1765 if (
s->has_residual_lsps) {
1767
1768 for (n = 0; n <
s->lsps; n++)
1769 prev_lsps[n] =
s->prev_lsps[n] -
mean_lsf[n];
1770
1771 if (
s->lsps == 10) {
1773 } else /* s->lsps == 16 */
1775
1776 for (n = 0; n <
s->lsps; n++) {
1778 lsps[1][n] =
mean_lsf[n] + (
a1[
s->lsps + n] -
a2[n * 2 + 1]);
1780 }
1781 for (n = 0; n < 3; n++)
1783 }
1784
1785 /* synth_superframe can run multiple times per packet
1786 * free potential previous frame */
1788
1789 /* get output buffer */
1792 return res;
1793 frame->nb_samples = n_samples;
1795
1796 /* Parse frames, optionally preceded by per-frame (independent) LSPs. */
1797 for (n = 0; n < 3; n++) {
1798 if (!
s->has_residual_lsps) {
1799 int m;
1800
1801 if (
s->lsps == 10) {
1803 } else /* s->lsps == 16 */
1805
1806 for (m = 0; m <
s->lsps; m++)
1809 }
1810
1813 lsps[n], n == 0 ?
s->prev_lsps : lsps[n - 1],
1816 *got_frame_ptr = 0;
1817 return res;
1818 }
1819 }
1820
1821 /* Statistics? FIXME - we don't check for length, a slight overrun
1822 * will be caught by internal buffer padding, and anything else
1823 * will be skipped, not read. */
1827 }
1828
1832 }
1833
1834 *got_frame_ptr = 1;
1835
1836 /* Update history */
1837 memcpy(
s->prev_lsps, lsps[2],
1838 s->lsps *
sizeof(*
s->prev_lsps));
1840 s->lsps *
sizeof(*synth));
1842 s->history_nsamples *
sizeof(*excitation));
1845 s->history_nsamples *
sizeof(*
s->zero_exc_pf));
1846
1847 return 0;
1848 }
1849
1850 /**
1851 * Parse the packet header at the start of each packet (input data to this
1852 * decoder).
1853 *
1854 * @param s WMA Voice decoding context private data
1855 * @return <0 on error, nb_superframes on success.
1856 */
1858 {
1860 unsigned int res, n_superframes = 0;
1861
1862 skip_bits(gb, 4);
// packet sequence number
1864 do {
1867
1868 res =
get_bits(gb, 6);
// number of superframes per packet
1869 // (minus first one if there is spillover)
1870 n_superframes += res;
1871 } while (res == 0x3F);
1872 s->spillover_nbits =
get_bits(gb,
s->spillover_bitsize);
1873
1875 }
1876
1877 /**
1878 * Copy (unaligned) bits from gb/data/size to pb.
1879 *
1880 * @param pb target buffer to copy bits into
1881 * @param data source buffer to copy bits from
1882 * @param size size of the source data, in bytes
1883 * @param gb bit I/O context specifying the current position in the source.
1884 * data. This function might use this to align the bit position to
1885 * a whole-byte boundary before calling #ff_copy_bits() on aligned
1886 * source data
1887 * @param nbits the amount of bits to copy from source to target
1888 *
1889 * @note after calling this function, the current position in the input bit
1890 * I/O context is undefined.
1891 */
1895 {
1896 int rmn_bytes, rmn_bits;
1897
1899 if (rmn_bits < nbits)
1900 return;
1902 return;
1903 rmn_bits &= 7; rmn_bytes >>= 3;
1904 if ((rmn_bits =
FFMIN(rmn_bits, nbits)) > 0)
1907 FFMIN(nbits - rmn_bits, rmn_bytes << 3));
1908 }
1909
1910 /**
1911 * Packet decoding: a packet is anything that the (ASF) demuxer contains,
1912 * and we expect that the demuxer / application provides it to us as such
1913 * (else you'll probably get garbage as output). Every packet has a size of
1914 * ctx->block_align bytes, starts with a packet header (see
1915 * #parse_packet_header()), and then a series of superframes. Superframe
1916 * boundaries may exceed packets, i.e. superframes can split data over
1917 * multiple (two) packets.
1918 *
1919 * For more information about frames, see #synth_superframe().
1920 */
1922 int *got_frame_ptr,
AVPacket *avpkt)
1923 {
1926 const uint8_t *buf = avpkt->
data;
1929
1930 /* Packets are sometimes a multiple of ctx->block_align, with a packet
1931 * header at each ctx->block_align bytes. However, FFmpeg's ASF demuxer
1932 * feeds us ASF packets, which may concatenate multiple "codec" packets
1933 * in a single "muxer" packet, so we artificially emulate that by
1934 * capping the packet size at ctx->block_align. */
1938 if (res < 0)
1939 return res;
1940
1941 /* size == ctx->block_align is used to indicate whether we are dealing with
1942 * a new packet or a packet of which we already read the packet header
1943 * previously. */
1944 if (!(
size %
ctx->block_align)) {
// new packet header
1946 s->spillover_nbits = 0;
1947 s->nb_superframes = 0;
1948 } else {
1950 return res;
1951 s->nb_superframes = res;
1952 }
1953
1954 /* If the packet header specifies a s->spillover_nbits, then we want
1955 * to push out all data of the previous packet (+ spillover) before
1956 * continuing to parse new superframes in the current packet. */
1957 if (
s->sframe_cache_size > 0) {
1959 if (cnt +
s->spillover_nbits > avpkt->
size * 8) {
1960 s->spillover_nbits = avpkt->
size * 8 - cnt;
1961 }
1964 s->sframe_cache_size +=
s->spillover_nbits;
1966 *got_frame_ptr) {
1967 cnt +=
s->spillover_nbits;
1968 s->skip_bits_next = cnt & 7;
1969 res = cnt >> 3;
1970 return res;
1971 } else
1974 }
else if (
s->spillover_nbits) {
1976 }
1977 }
else if (
s->skip_bits_next)
1979
1980 /* Try parsing superframes in current packet */
1981 s->sframe_cache_size = 0;
1982 s->skip_bits_next = 0;
1984 if (
s->nb_superframes-- == 0) {
1985 *got_frame_ptr = 0;
1987 }
else if (
s->nb_superframes > 0) {
1989 return res;
1990 } else if (*got_frame_ptr) {
1992 s->skip_bits_next = cnt & 7;
1993 res = cnt >> 3;
1994 return res;
1995 }
1996 }
else if ((
s->sframe_cache_size =
pos) > 0) {
1997 /* ... cache it for spillover in next packet */
2000 // FIXME bad - just copy bytes as whole and add use the
2001 // skip_bits_next field
2002 }
2003
2005 }
2006
2008 {
2010
2016 }
2017
2018 return 0;
2019 }
2020
2022 .
p.
name =
"wmavoice",
2033 };