FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavutil/fixed_dsp.h
Date: 2026-04-24 19:58:39
Exec Total Coverage
Lines: 16 17 94.1%
Functions: 1 1 100.0%
Branches: 6 8 75.0%
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1 /*
2 * Copyright (c) 2012
3 * MIPS Technologies, Inc., California.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the MIPS Technologies, Inc., nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * Author: Nedeljko Babic (nbabic@mips.com)
30 *
31 * This file is part of FFmpeg.
32 *
33 * FFmpeg is free software; you can redistribute it and/or
34 * modify it under the terms of the GNU Lesser General Public
35 * License as published by the Free Software Foundation; either
36 * version 2.1 of the License, or (at your option) any later version.
37 *
38 * FFmpeg is distributed in the hope that it will be useful,
39 * but WITHOUT ANY WARRANTY; without even the implied warranty of
40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
41 * Lesser General Public License for more details.
42 *
43 * You should have received a copy of the GNU Lesser General Public
44 * License along with FFmpeg; if not, write to the Free Software
45 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
46 */
47
48 #ifndef AVUTIL_FIXED_DSP_H
49 #define AVUTIL_FIXED_DSP_H
50
51 #include <stdint.h>
52 #include "attributes.h"
53 #include "libavcodec/mathops.h"
54
55 typedef struct AVFixedDSPContext {
56 /* Assume len is a multiple of 16, and arrays are 32-byte aligned */
57 /* Results of multiplications are scaled down by 31 bit (and rounded) if not
58 * stated otherwise */
59
60 /**
61 * Overlap/add with window function.
62 * Result is scaled down by "bits" bits.
63 * Used primarily by MDCT-based audio codecs.
64 * Source and destination vectors must overlap exactly or not at all.
65 *
66 * @param dst result vector
67 * constraints: 16-byte aligned
68 * @param src0 first source vector
69 * constraints: 16-byte aligned
70 * @param src1 second source vector
71 * constraints: 16-byte aligned
72 * @param win half-window vector
73 * constraints: 16-byte aligned
74 * @param len length of vector
75 * constraints: multiple of 4
76 * @param bits scaling parameter
77 *
78 */
79 void (*vector_fmul_window_scaled)(int16_t *dst, const int32_t *src0, const int32_t *src1, const int32_t *win, int len, uint8_t bits);
80
81 /**
82 * Overlap/add with window function.
83 * Used primarily by MDCT-based audio codecs.
84 * Source and destination vectors must overlap exactly or not at all.
85 *
86 * @param dst result vector
87 * constraints: 32-byte aligned
88 * @param src0 first source vector
89 * constraints: 16-byte aligned
90 * @param src1 second source vector
91 * constraints: 16-byte aligned
92 * @param win half-window vector
93 * constraints: 16-byte aligned
94 * @param len length of vector
95 * constraints: multiple of 4
96 */
97 void (*vector_fmul_window)(int32_t *dst, const int32_t *src0, const int32_t *src1, const int32_t *win, int len);
98
99 /**
100 * Fixed-point multiplication that calculates the entry wise product of two
101 * vectors of integers and stores the result in a vector of integers.
102 *
103 * @param dst output vector
104 * constraints: 32-byte aligned
105 * @param src0 first input vector
106 * constraints: 32-byte aligned
107 * @param src1 second input vector
108 * constraints: 32-byte aligned
109 * @param len number of elements in the input
110 * constraints: multiple of 16
111 */
112 void (*vector_fmul)(int *dst, const int *src0, const int *src1,
113 int len);
114
115 void (*vector_fmul_reverse)(int *dst, const int *src0, const int *src1, int len);
116 /**
117 * Calculate the entry wise product of two vectors of integers, add a third vector of
118 * integers and store the result in a vector of integers.
119 *
120 * @param dst output vector
121 * constraints: 32-byte aligned
122 * @param src0 first input vector
123 * constraints: 32-byte aligned
124 * @param src1 second input vector
125 * constraints: 32-byte aligned
126 * @param src2 third input vector
127 * constraints: 32-byte aligned
128 * @param len number of elements in the input
129 * constraints: multiple of 16
130 */
131 void (*vector_fmul_add)(int *dst, const int *src0, const int *src1,
132 const int *src2, int len);
133
134 /**
135 * Calculate the scalar product of two vectors of integers.
136 *
137 * @param v1 first vector, 16-byte aligned
138 * @param v2 second vector, 16-byte aligned
139 * @param len length of vectors, multiple of 4
140 *
141 * @return sum of elementwise products
142 */
143 int (*scalarproduct_fixed)(const int *v1, const int *v2, int len);
144
145 /**
146 * Calculate the sum and difference of two vectors of integers.
147 *
148 * @param v1 first input vector, sum output, 16-byte aligned
149 * @param v2 second input vector, difference output, 16-byte aligned
150 * @param len length of vectors, multiple of 4
151 */
152 void (*butterflies_fixed)(int *restrict v1, int *restrict v2, int len);
153 } AVFixedDSPContext;
154
155 /**
156 * Allocate and initialize a fixed DSP context.
157 * note: should be freed with a av_free call when no longer needed.
158 *
159 * @param strict setting to non-zero avoids using functions which may not be IEEE-754 compliant
160 */
161 AVFixedDSPContext * avpriv_alloc_fixed_dsp(int strict);
162
163 void ff_fixed_dsp_init_riscv(AVFixedDSPContext *fdsp);
164 void ff_fixed_dsp_init_x86(AVFixedDSPContext *fdsp);
165
166 /**
167 * Calculate the square root
168 *
169 * @param x input fixed point number
170 *
171 * @param bits format of fixed point number (32 - bits).bits
172 *
173 * note: input is normalized to (0, 1) fixed point value
174 */
175
176 137931 static av_always_inline int fixed_sqrt(int x, int bits)
177 {
178 int retval, bit_mask, guess, square, i;
179 int64_t accu;
180 137931 int shift1 = 30 - bits;
181 137931 int shift2 = bits - 15;
182
183
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 137931 if (shift1 > 0) retval = ff_sqrt(x << shift1);
184 137931 else retval = ff_sqrt(x >> -shift1);
185
186
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 137931 if (shift2 > 0) {
187 137931 retval = retval << shift2;
188 137931 bit_mask = (1 << (shift2 - 1));
189
190
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 2344827 for (i=0; i<shift2; i++){
191 2206896 guess = retval + bit_mask;
192 2206896 accu = (int64_t)guess * guess;
193 2206896 square = (int)((accu + bit_mask) >> bits);
194
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 2206896 if (x >= square)
195 1102901 retval += bit_mask;
196 2206896 bit_mask >>= 1;
197 }
198
199 }
200 ✗ else retval >>= (-shift2);
201
202 137931 return retval;
203 }
204
205 #endif /* AVUTIL_FIXED_DSP_H */
206