Move bessel_i0() from swresample/resample to avutil/mathematics

0th order modified bessel function of the first kind are used in multiple places, lets avoid having 3+ different implementations I picked this one as its accurate and quite fast, it can be replaced if a better one is found

Michael Niedermayer committed 3 years ago

Commit 75918011 parent 0c78b0d5 files · +113 −106Browse files

Unified · Split

5 files

doc/APIchanges +3 −0
libavutil/mathematics.c +104 −0
libavutil/mathematics.h +4 −0
libavutil/version.h +1 −1
libswresample/resample.c +1 −105

doc/APIchanges+3−0

@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09 · 1 unmodified line
2	2
3	3	API changes, most recent first:
4	4
	5	+2023-05-29 - xxxxxxxxxx - lavu 58.12.100 - mathematics.h
	6	+ Add av_bessel_i0()
	7	+
5	8	2023-05-xx - xxxxxxxxxx - lavc 60.15.100 - avcodec.h
6	9	Add AVHWAccel.update_thread_context, AVHWAccel.free_frame_priv,
7	10	AVHWAccel.flush.

libavutil/mathematics.c+104−0

@@ -213,3 +213,107 @@ int64_t av_add_stable(AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t i · 212 unmodified lines
213	213	return av_sat_add64(av_rescale_q(old + 1, inc_tb, ts_tb), ts - old_ts);
214	214	}
215	215	}
	216	+
	217	+static inline double eval_poly(const double *coeff, int size, double x) {
	218	+ double sum = coeff[size-1];
	219	+ int i;
	220	+ for (i = size-2; i >= 0; --i) {
	221	+ sum *= x;
	222	+ sum += coeff[i];
	223	+ }
	224	+ return sum;
	225	+}
	226	+
	227	+/**
	228	+ * 0th order modified bessel function of the first kind.
	229	+ * Algorithm taken from the Boost project, source:
	230	+ * https://searchcode.com/codesearch/view/14918379/
	231	+ * Use, modification and distribution are subject to the
	232	+ * Boost Software License, Version 1.0 (see notice below).
	233	+ * Boost Software License - Version 1.0 - August 17th, 2003
	234	+Permission is hereby granted, free of charge, to any person or organization
	235	+obtaining a copy of the software and accompanying documentation covered by
	236	+this license (the "Software") to use, reproduce, display, distribute,
	237	+execute, and transmit the Software, and to prepare derivative works of the
	238	+Software, and to permit third-parties to whom the Software is furnished to
	239	+do so, all subject to the following:
	240	+
	241	+The copyright notices in the Software and this entire statement, including
	242	+the above license grant, this restriction and the following disclaimer,
	243	+must be included in all copies of the Software, in whole or in part, and
	244	+all derivative works of the Software, unless such copies or derivative
	245	+works are solely in the form of machine-executable object code generated by
	246	+a source language processor.
	247	+
	248	+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	249	+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	250	+FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
	251	+SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
	252	+FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
	253	+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
	254	+DEALINGS IN THE SOFTWARE.
	255	+ */
	256	+
	257	+double av_bessel_i0(double x) {
	258	+// Modified Bessel function of the first kind of order zero
	259	+// minimax rational approximations on intervals, see
	260	+// Blair and Edwards, Chalk River Report AECL-4928, 1974
	261	+ static const double p1[] = {
	262	+ -2.2335582639474375249e+15,
	263	+ -5.5050369673018427753e+14,
	264	+ -3.2940087627407749166e+13,
	265	+ -8.4925101247114157499e+11,
	266	+ -1.1912746104985237192e+10,
	267	+ -1.0313066708737980747e+08,
	268	+ -5.9545626019847898221e+05,
	269	+ -2.4125195876041896775e+03,
	270	+ -7.0935347449210549190e+00,
	271	+ -1.5453977791786851041e-02,
	272	+ -2.5172644670688975051e-05,
	273	+ -3.0517226450451067446e-08,
	274	+ -2.6843448573468483278e-11,
	275	+ -1.5982226675653184646e-14,
	276	+ -5.2487866627945699800e-18,
	277	+ };
	278	+ static const double q1[] = {
	279	+ -2.2335582639474375245e+15,
	280	+ 7.8858692566751002988e+12,
	281	+ -1.2207067397808979846e+10,
	282	+ 1.0377081058062166144e+07,
	283	+ -4.8527560179962773045e+03,
	284	+ 1.0,
	285	+ };
	286	+ static const double p2[] = {
	287	+ -2.2210262233306573296e-04,
	288	+ 1.3067392038106924055e-02,
	289	+ -4.4700805721174453923e-01,
	290	+ 5.5674518371240761397e+00,
	291	+ -2.3517945679239481621e+01,
	292	+ 3.1611322818701131207e+01,
	293	+ -9.6090021968656180000e+00,
	294	+ };
	295	+ static const double q2[] = {
	296	+ -5.5194330231005480228e-04,
	297	+ 3.2547697594819615062e-02,
	298	+ -1.1151759188741312645e+00,
	299	+ 1.3982595353892851542e+01,
	300	+ -6.0228002066743340583e+01,
	301	+ 8.5539563258012929600e+01,
	302	+ -3.1446690275135491500e+01,
	303	+ 1.0,
	304	+ };
	305	+ double y, r, factor;
	306	+ if (x == 0)
	307	+ return 1.0;
	308	+ x = fabs(x);
	309	+ if (x <= 15) {
	310	+ y = x * x;
	311	+ return eval_poly(p1, FF_ARRAY_ELEMS(p1), y) / eval_poly(q1, FF_ARRAY_ELEMS(q1), y);
	312	+ }
	313	+ else {
	314	+ y = 1 / x - 1.0 / 15;
	315	+ r = eval_poly(p2, FF_ARRAY_ELEMS(p2), y) / eval_poly(q2, FF_ARRAY_ELEMS(q2), y);
	316	+ factor = exp(x) / sqrt(x);
	317	+ return factor * r;
	318	+ }
	319	+}

libavutil/mathematics.h+4−0

@@ -288,6 +288,10 @@ int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts, AVRational fs_tb, int · 287 unmodified lines
288	288	*/
289	289	int64_t av_add_stable(AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t inc);
290	290
	291	+/**
	292	+ * 0th order modified bessel function of the first kind.
	293	+ */
	294	+double av_bessel_i0(double x);
291	295
292	296	/**
293	297	* @}

libavutil/version.h+1−1

@@ -79,7 +79,7 @@ · 78 unmodified lines
79	79	*/
80	80
81	81	#define LIBAVUTIL_VERSION_MAJOR 58
82		−#define LIBAVUTIL_VERSION_MINOR 11
	82	+#define LIBAVUTIL_VERSION_MINOR 12
83	83	#define LIBAVUTIL_VERSION_MICRO 100
84	84
85	85	#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \

libswresample/resample.c+1−105

@@ -30,110 +30,6 @@ · 29 unmodified lines
30	30	#include "libavutil/cpu.h"
31	31	#include "resample.h"
32	32
33		−static inline double eval_poly(const double *coeff, int size, double x) {
34		− double sum = coeff[size-1];
35		− int i;
36		− for (i = size-2; i >= 0; --i) {
37		− sum *= x;
38		− sum += coeff[i];
39		− }
40		− return sum;
41		−}
42		−
43		−/**
44		− * 0th order modified bessel function of the first kind.
45		− * Algorithm taken from the Boost project, source:
46		− * https://searchcode.com/codesearch/view/14918379/
47		− * Use, modification and distribution are subject to the
48		− * Boost Software License, Version 1.0 (see notice below).
49		− * Boost Software License - Version 1.0 - August 17th, 2003
50		−Permission is hereby granted, free of charge, to any person or organization
51		−obtaining a copy of the software and accompanying documentation covered by
52		−this license (the "Software") to use, reproduce, display, distribute,
53		−execute, and transmit the Software, and to prepare derivative works of the
54		−Software, and to permit third-parties to whom the Software is furnished to
55		−do so, all subject to the following:
56		−
57		−The copyright notices in the Software and this entire statement, including
58		−the above license grant, this restriction and the following disclaimer,
59		−must be included in all copies of the Software, in whole or in part, and
60		−all derivative works of the Software, unless such copies or derivative
61		−works are solely in the form of machine-executable object code generated by
62		−a source language processor.
63		−
64		−THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
65		−IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
66		−FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
67		−SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
68		−FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
69		−ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
70		−DEALINGS IN THE SOFTWARE.
71		− */
72		−
73		−static double bessel(double x) {
74		−// Modified Bessel function of the first kind of order zero
75		−// minimax rational approximations on intervals, see
76		−// Blair and Edwards, Chalk River Report AECL-4928, 1974
77		− static const double p1[] = {
78		− -2.2335582639474375249e+15,
79		− -5.5050369673018427753e+14,
80		− -3.2940087627407749166e+13,
81		− -8.4925101247114157499e+11,
82		− -1.1912746104985237192e+10,
83		− -1.0313066708737980747e+08,
84		− -5.9545626019847898221e+05,
85		− -2.4125195876041896775e+03,
86		− -7.0935347449210549190e+00,
87		− -1.5453977791786851041e-02,
88		− -2.5172644670688975051e-05,
89		− -3.0517226450451067446e-08,
90		− -2.6843448573468483278e-11,
91		− -1.5982226675653184646e-14,
92		− -5.2487866627945699800e-18,
93		− };
94		− static const double q1[] = {
95		− -2.2335582639474375245e+15,
96		− 7.8858692566751002988e+12,
97		− -1.2207067397808979846e+10,
98		− 1.0377081058062166144e+07,
99		− -4.8527560179962773045e+03,
100		− 1.0,
101		− };
102		− static const double p2[] = {
103		− -2.2210262233306573296e-04,
104		− 1.3067392038106924055e-02,
105		− -4.4700805721174453923e-01,
106		− 5.5674518371240761397e+00,
107		− -2.3517945679239481621e+01,
108		− 3.1611322818701131207e+01,
109		− -9.6090021968656180000e+00,
110		− };
111		− static const double q2[] = {
112		− -5.5194330231005480228e-04,
113		− 3.2547697594819615062e-02,
114		− -1.1151759188741312645e+00,
115		− 1.3982595353892851542e+01,
116		− -6.0228002066743340583e+01,
117		− 8.5539563258012929600e+01,
118		− -3.1446690275135491500e+01,
119		− 1.0,
120		− };
121		− double y, r, factor;
122		− if (x == 0)
123		− return 1.0;
124		− x = fabs(x);
125		− if (x <= 15) {
126		− y = x * x;
127		− return eval_poly(p1, FF_ARRAY_ELEMS(p1), y) / eval_poly(q1, FF_ARRAY_ELEMS(q1), y);
128		− }
129		− else {
130		− y = 1 / x - 1.0 / 15;
131		− r = eval_poly(p2, FF_ARRAY_ELEMS(p2), y) / eval_poly(q2, FF_ARRAY_ELEMS(q2), y);
132		− factor = exp(x) / sqrt(x);
133		− return factor * r;
134		− }
135		−}
136		−
137	33	/**
138	34	* builds a polyphase filterbank.
139	35	* @param factor resampling factor
@@ -189,7 +85,7 @@ static int build_filter(ResampleContext c, void filter, double factor, int tap · 49 unmodified lines
189	85	break;
190	86	case SWR_FILTER_TYPE_KAISER:
191	87	w = 2.0x / (factortap_count*M_PI);
192		− y = bessel(kaiser_betasqrt(FFMAX(1-w*w, 0)));
	88	+ y = av_bessel_i0(kaiser_betasqrt(FFMAX(1-w*w, 0)));
193	89	break;
194	90	default:
195	91	av_assert0(0);

Move bessel_i0() from swresample/resample to avutil/mathematics

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