1/*
2 * Copyright (C) 2010 Georg Martius <georg.martius@web.de>
3 * Copyright (C) 2010 Daniel G. Taylor <dan@programmer-art.org>
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22#ifndef AVFILTER_TRANSFORM_H
23#define AVFILTER_TRANSFORM_H
24
25#include <stdint.h>
26
27/**
28 * @file
29 * transform input video
30 *
31 * All matrices are defined as a single 9-item block of contiguous memory. For
32 * example, the identity matrix would be:
33 *
34 *     float *matrix = {1, 0, 0,
35 *                      0, 1, 0,
36 *                      0, 0, 1};
37 */
38
39enum InterpolateMethod {
40    INTERPOLATE_NEAREST,        //< Nearest-neighbor (fast)
41    INTERPOLATE_BILINEAR,       //< Bilinear
42    INTERPOLATE_BIQUADRATIC,    //< Biquadratic (best)
43    INTERPOLATE_COUNT,          //< Number of interpolation methods
44};
45
46// Shortcuts for the fastest and best interpolation methods
47#define INTERPOLATE_DEFAULT INTERPOLATE_BILINEAR
48#define INTERPOLATE_FAST    INTERPOLATE_NEAREST
49#define INTERPOLATE_BEST    INTERPOLATE_BIQUADRATIC
50
51enum FillMethod {
52    FILL_BLANK,         //< Fill zeroes at blank locations
53    FILL_ORIGINAL,      //< Original image at blank locations
54    FILL_CLAMP,         //< Extruded edge value at blank locations
55    FILL_MIRROR,        //< Mirrored edge at blank locations
56    FILL_COUNT,         //< Number of edge fill methods
57};
58
59// Shortcuts for fill methods
60#define FILL_DEFAULT FILL_ORIGINAL
61
62/**
63 * Get an affine transformation matrix from a given translation, rotation, and
64 * zoom factor. The matrix will look like:
65 *
66 * [ zoom * cos(angle),           -sin(angle),     x_shift,
67 *          sin(angle),     zoom * cos(angle),     y_shift,
68 *                   0,                     0,           1 ]
69 *
70 * @param x_shift horizontal translation
71 * @param y_shift vertical translation
72 * @param angle   rotation in radians
73 * @param zoom    scale percent (1.0 = 100%)
74 * @param matrix  9-item affine transformation matrix
75 */
76void avfilter_get_matrix(float x_shift, float y_shift, float angle, float zoom, float *matrix);
77
78/**
79 * Add two matrices together. result = m1 + m2.
80 *
81 * @param m1     9-item transformation matrix
82 * @param m2     9-item transformation matrix
83 * @param result 9-item transformation matrix
84 */
85void avfilter_add_matrix(const float *m1, const float *m2, float *result);
86
87/**
88 * Subtract one matrix from another. result = m1 - m2.
89 *
90 * @param m1     9-item transformation matrix
91 * @param m2     9-item transformation matrix
92 * @param result 9-item transformation matrix
93 */
94void avfilter_sub_matrix(const float *m1, const float *m2, float *result);
95
96/**
97 * Multiply a matrix by a scalar value. result = m1 * scalar.
98 *
99 * @param m1     9-item transformation matrix
100 * @param scalar a number
101 * @param result 9-item transformation matrix
102 */
103void avfilter_mul_matrix(const float *m1, float scalar, float *result);
104
105/**
106 * Do an affine transformation with the given interpolation method. This
107 * multiplies each vector [x,y,1] by the matrix and then interpolates to
108 * get the final value.
109 *
110 * @param src         source image
111 * @param dst         destination image
112 * @param src_stride  source image line size in bytes
113 * @param dst_stride  destination image line size in bytes
114 * @param width       image width in pixels
115 * @param height      image height in pixels
116 * @param matrix      9-item affine transformation matrix
117 * @param interpolate pixel interpolation method
118 * @param fill        edge fill method
119 * @return negative on error
120 */
121int avfilter_transform(const uint8_t *src, uint8_t *dst,
122                        int src_stride, int dst_stride,
123                        int width, int height, const float *matrix,
124                        enum InterpolateMethod interpolate,
125                        enum FillMethod fill);
126
127#endif /* AVFILTER_TRANSFORM_H */
128