| /* |
| * 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 |
| */ |
| |
| #ifndef AVFILTER_HERMITE_H |
| #define AVFILTER_HERMITE_H |
| |
| 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; |
| } |
| |
| #endif /* AVFILTER_HERMITE_H */ |
