2 * Copyright (C) 2010 Georg Martius <georg.martius@web.de>
3 * Copyright (C) 2010 Daniel G. Taylor <dan@programmer-art.org>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * transform input video
26 * All matrices are defined as a single 9-item block of contiguous memory. For
27 * example, the identity matrix would be:
29 * float *matrix = {1, 0, 0,
34 enum InterpolateMethod {
35 INTERPOLATE_NEAREST, //< Nearest-neighbor (fast)
36 INTERPOLATE_BILINEAR, //< Bilinear
37 INTERPOLATE_BIQUADRATIC, //< Biquadratic (best)
38 INTERPOLATE_COUNT, //< Number of interpolation methods
41 // Shortcuts for the fastest and best interpolation methods
42 #define INTERPOLATE_DEFAULT INTERPOLATE_BILINEAR
43 #define INTERPOLATE_FAST INTERPOLATE_NEAREST
44 #define INTERPOLATE_BEST INTERPOLATE_BIQUADRATIC
47 FILL_BLANK, //< Fill zeroes at blank locations
48 FILL_ORIGINAL, //< Original image at blank locations
49 FILL_CLAMP, //< Extruded edge value at blank locations
50 FILL_MIRROR, //< Mirrored edge at blank locations
51 FILL_COUNT, //< Number of edge fill methods
54 // Shortcuts for fill methods
55 #define FILL_DEFAULT FILL_ORIGINAL
58 * Get an affine transformation matrix from a given translation, rotation, and
59 * zoom factor. The matrix will look like:
61 * [ zoom * cos(angle), -sin(angle), x_shift,
62 * sin(angle), zoom * cos(angle), y_shift,
66 * x_shift: Horizontal translation
67 * y_shift: Vertical translation
68 * angle: Rotation in radians
69 * zoom: Scale percent (1.0 = 100%)
70 * matrix: 9-item affine transformation matrix
72 void avfilter_get_matrix(float x_shift, float y_shift, float angle, float zoom, float *matrix);
75 * Add two matrices together. result = m1 + m2.
78 * m1: 9-item transformation matrix
79 * m2: 9-item transformation matrix
80 * result: 9-item transformation matrix
82 void avfilter_add_matrix(const float *m1, const float *m2, float *result);
85 * Subtract one matrix from another. result = m1 - m2.
88 * m1: 9-item transformation matrix
89 * m2: 9-item transformation matrix
90 * result: 9-item transformation matrix
92 void avfilter_sub_matrix(const float *m1, const float *m2, float *result);
95 * Multiply a matrix by a scalar value. result = m1 * scalar.
98 * m1: 9-item transformation matrix
100 * result: 9-item transformation matrix
102 void avfilter_mul_matrix(const float *m1, float scalar, float *result);
105 * Do an affine transformation with the given interpolation method. This
106 * multiplies each vector [x,y,1] by the matrix and then interpolates to
107 * get the final value.
111 * dst: Destination image
112 * src_stride: Source image line size in bytes
113 * dst_stride: Destination image line size in bytes
114 * width: Image width in pixels
115 * height: Image height in pixels
116 * matrix: 9-item affine transformation matrix
117 * interpolate: Pixel interpolation method
118 * fill: Edge fill method
120 void avfilter_transform(const uint8_t *src, uint8_t *dst,
121 int src_stride, int dst_stride,
122 int width, int height, const float *matrix,
123 enum InterpolateMethod interpolate,
124 enum FillMethod fill);