1 /*
2  *  Copyright (c) 2019 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef VPX_VPX_UTIL_VPX_TIMESTAMP_H_
12 #define VPX_VPX_UTIL_VPX_TIMESTAMP_H_
13 
14 #ifdef __cplusplus
15 extern "C" {
16 #endif  // __cplusplus
17 
18 // Rational Number with an int64 numerator
19 typedef struct vpx_rational64 {
20   int64_t num;       // fraction numerator
21   int den;           // fraction denominator
22 } vpx_rational64_t;  // alias for struct vpx_rational64_t
23 
gcd(int64_t a,int b)24 static INLINE int gcd(int64_t a, int b) {
25   int r;  // remainder
26   while (b > 0) {
27     r = (int)(a % b);
28     a = b;
29     b = r;
30   }
31 
32   return (int)a;
33 }
34 
reduce_ratio(vpx_rational64_t * ratio)35 static INLINE void reduce_ratio(vpx_rational64_t *ratio) {
36   const int denom = gcd(ratio->num, ratio->den);
37   ratio->num /= denom;
38   ratio->den /= denom;
39 }
40 
41 #ifdef __cplusplus
42 }  // extern "C"
43 #endif  // __cplusplus
44 
45 #endif  // VPX_VPX_UTIL_VPX_TIMESTAMP_H_
46