| /* | |
| * This file is part of FFmpeg. | |
| * | |
| * FFmpeg is free software; you can redistribute it and/or | |
| * modify it under the terms of the GNU Lesser General Public | |
| * License as published by the Free Software Foundation; either | |
| * version 2.1 of the License, or (at your option) any later version. | |
| * | |
| * FFmpeg is distributed in the hope that it will be useful, | |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| * Lesser General Public License for more details. | |
| * | |
| * You should have received a copy of the GNU Lesser General Public | |
| * License along with FFmpeg; if not, write to the Free Software | |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| */ | |
| static inline double hermite_interpolation(double x, double x0, double x1, | |
| double p0, double p1, | |
| double m0, double m1) | |
| { | |
| double width = x1 - x0; | |
| double t = (x - x0) / width; | |
| double t2, t3; | |
| double ct0, ct1, ct2, ct3; | |
| m0 *= width; | |
| m1 *= width; | |
| t2 = t*t; | |
| t3 = t2*t; | |
| ct0 = p0; | |
| ct1 = m0; | |
| ct2 = -3 * p0 - 2 * m0 + 3 * p1 - m1; | |
| ct3 = 2 * p0 + m0 - 2 * p1 + m1; | |
| return ct3 * t3 + ct2 * t2 + ct1 * t + ct0; | |
| } | |