FFmpeg
celp_filters.c
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1 /*
2  * various filters for ACELP-based codecs
3  *
4  * Copyright (c) 2008 Vladimir Voroshilov
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <inttypes.h>
24 
25 #include "avcodec.h"
26 #include "celp_filters.h"
27 #include "libavutil/avassert.h"
28 #include "libavutil/common.h"
29 
30 void ff_celp_convolve_circ(int16_t* fc_out, const int16_t* fc_in,
31  const int16_t* filter, int len)
32 {
33  int i, k;
34 
35  memset(fc_out, 0, len * sizeof(int16_t));
36 
37  /* Since there are few pulses over an entire subframe (i.e. almost
38  all fc_in[i] are zero) it is faster to loop over fc_in first. */
39  for (i = 0; i < len; i++) {
40  if (fc_in[i]) {
41  for (k = 0; k < i; k++)
42  fc_out[k] += (fc_in[i] * filter[len + k - i]) >> 15;
43 
44  for (k = i; k < len; k++)
45  fc_out[k] += (fc_in[i] * filter[ k - i]) >> 15;
46  }
47  }
48 }
49 
50 void ff_celp_circ_addf(float *out, const float *in,
51  const float *lagged, int lag, float fac, int n)
52 {
53  int k;
54  for (k = 0; k < lag; k++)
55  out[k] = in[k] + fac * lagged[n + k - lag];
56  for (; k < n; k++)
57  out[k] = in[k] + fac * lagged[ k - lag];
58 }
59 
60 int ff_celp_lp_synthesis_filter(int16_t *out, const int16_t *filter_coeffs,
61  const int16_t *in, int buffer_length,
62  int filter_length, int stop_on_overflow,
63  int shift, int rounder)
64 {
65  int i,n;
66 
67  for (n = 0; n < buffer_length; n++) {
68  int sum = -rounder, sum1;
69  for (i = 1; i <= filter_length; i++)
70  sum += (unsigned)(filter_coeffs[i-1] * out[n-i]);
71 
72  sum1 = ((-sum >> 12) + in[n]) >> shift;
73  sum = av_clip_int16(sum1);
74 
75  if (stop_on_overflow && sum != sum1)
76  return 1;
77 
78  out[n] = sum;
79  }
80 
81  return 0;
82 }
83 
84 void ff_celp_lp_synthesis_filterf(float *out, const float *filter_coeffs,
85  const float* in, int buffer_length,
86  int filter_length)
87 {
88  int i,n;
89 
90 #if 0 // Unoptimized code path for improved readability
91  for (n = 0; n < buffer_length; n++) {
92  out[n] = in[n];
93  for (i = 1; i <= filter_length; i++)
94  out[n] -= filter_coeffs[i-1] * out[n-i];
95  }
96 #else
97  float out0, out1, out2, out3;
98  float old_out0, old_out1, old_out2, old_out3;
99  float a,b,c;
100 
101  a = filter_coeffs[0];
102  b = filter_coeffs[1];
103  c = filter_coeffs[2];
104  b -= filter_coeffs[0] * filter_coeffs[0];
105  c -= filter_coeffs[1] * filter_coeffs[0];
106  c -= filter_coeffs[0] * b;
107 
108  av_assert2((filter_length&1)==0 && filter_length>=4);
109 
110  old_out0 = out[-4];
111  old_out1 = out[-3];
112  old_out2 = out[-2];
113  old_out3 = out[-1];
114  for (n = 0; n <= buffer_length - 4; n+=4) {
115  float tmp0,tmp1,tmp2;
116  float val;
117 
118  out0 = in[0];
119  out1 = in[1];
120  out2 = in[2];
121  out3 = in[3];
122 
123  out0 -= filter_coeffs[2] * old_out1;
124  out1 -= filter_coeffs[2] * old_out2;
125  out2 -= filter_coeffs[2] * old_out3;
126 
127  out0 -= filter_coeffs[1] * old_out2;
128  out1 -= filter_coeffs[1] * old_out3;
129 
130  out0 -= filter_coeffs[0] * old_out3;
131 
132  val = filter_coeffs[3];
133 
134  out0 -= val * old_out0;
135  out1 -= val * old_out1;
136  out2 -= val * old_out2;
137  out3 -= val * old_out3;
138 
139  for (i = 5; i < filter_length; i += 2) {
140  old_out3 = out[-i];
141  val = filter_coeffs[i-1];
142 
143  out0 -= val * old_out3;
144  out1 -= val * old_out0;
145  out2 -= val * old_out1;
146  out3 -= val * old_out2;
147 
148  old_out2 = out[-i-1];
149 
150  val = filter_coeffs[i];
151 
152  out0 -= val * old_out2;
153  out1 -= val * old_out3;
154  out2 -= val * old_out0;
155  out3 -= val * old_out1;
156 
157  FFSWAP(float, old_out0, old_out2);
158  old_out1 = old_out3;
159  }
160 
161  tmp0 = out0;
162  tmp1 = out1;
163  tmp2 = out2;
164 
165  out3 -= a * tmp2;
166  out2 -= a * tmp1;
167  out1 -= a * tmp0;
168 
169  out3 -= b * tmp1;
170  out2 -= b * tmp0;
171 
172  out3 -= c * tmp0;
173 
174 
175  out[0] = out0;
176  out[1] = out1;
177  out[2] = out2;
178  out[3] = out3;
179 
180  old_out0 = out0;
181  old_out1 = out1;
182  old_out2 = out2;
183  old_out3 = out3;
184 
185  out += 4;
186  in += 4;
187  }
188 
189  out -= n;
190  in -= n;
191  for (; n < buffer_length; n++) {
192  out[n] = in[n];
193  for (i = 1; i <= filter_length; i++)
194  out[n] -= filter_coeffs[i-1] * out[n-i];
195  }
196 #endif
197 }
198 
199 void ff_celp_lp_zero_synthesis_filterf(float *out, const float *filter_coeffs,
200  const float *in, int buffer_length,
201  int filter_length)
202 {
203  int i,n;
204 
205  for (n = 0; n < buffer_length; n++) {
206  out[n] = in[n];
207  for (i = 1; i <= filter_length; i++)
208  out[n] += filter_coeffs[i-1] * in[n-i];
209  }
210 }
211 
213 {
216 
217  if(HAVE_MIPSFPU)
219 }
const char const char void * val
Definition: avisynth_c.h:863
void ff_celp_lp_synthesis_filterf(float *out, const float *filter_coeffs, const float *in, int buffer_length, int filter_length)
LP synthesis filter.
Definition: celp_filters.c:84
static int shift(int a, int b)
Definition: sonic.c:82
int ff_celp_lp_synthesis_filter(int16_t *out, const int16_t *filter_coeffs, const int16_t *in, int buffer_length, int filter_length, int stop_on_overflow, int shift, int rounder)
LP synthesis filter.
Definition: celp_filters.c:60
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
void(* celp_lp_zero_synthesis_filterf)(float *out, const float *filter_coeffs, const float *in, int buffer_length, int filter_length)
LP zero synthesis filter.
Definition: celp_filters.h:65
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
void(* celp_lp_synthesis_filterf)(float *out, const float *filter_coeffs, const float *in, int buffer_length, int filter_length)
LP synthesis filter.
Definition: celp_filters.h:45
simple assert() macros that are a bit more flexible than ISO C assert().
void ff_celp_convolve_circ(int16_t *fc_out, const int16_t *fc_in, const int16_t *filter, int len)
Circularly convolve fixed vector with a phase dispersion impulse response filter (D.6.2 of G.729 and 6.1.5 of AMR).
Definition: celp_filters.c:30
#define b
Definition: input.c:41
int n
Definition: avisynth_c.h:760
Libavcodec external API header.
void ff_celp_circ_addf(float *out, const float *in, const float *lagged, int lag, float fac, int n)
Add an array to a rotated array.
Definition: celp_filters.c:50
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31))))#define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac){}void ff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map){AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);return NULL;}return ac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;}int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){int use_generic=1;int len=in->nb_samples;int p;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%d samples - audio_convert: %s to %s (dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
void ff_celp_filter_init(CELPFContext *c)
Initialize CELPFContext.
Definition: celp_filters.c:212
void ff_celp_lp_zero_synthesis_filterf(float *out, const float *filter_coeffs, const float *in, int buffer_length, int filter_length)
LP zero synthesis filter.
Definition: celp_filters.c:199
common internal and external API header
int len
FILE * out
Definition: movenc.c:54
#define FFSWAP(type, a, b)
Definition: common.h:99
void ff_celp_filter_init_mips(CELPFContext *c)