2 * This file is part of Libav.
4 * Libav is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
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10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with Libav; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef AVUTIL_IMGUTILS_H
20 #define AVUTIL_IMGUTILS_H
24 * misc image utilities
26 * @addtogroup lavu_picture
35 * Compute the max pixel step for each plane of an image with a
36 * format described by pixdesc.
38 * The pixel step is the distance in bytes between the first byte of
39 * the group of bytes which describe a pixel component and the first
40 * byte of the successive group in the same plane for the same
43 * @param max_pixsteps an array which is filled with the max pixel step
44 * for each plane. Since a plane may contain different pixel
45 * components, the computed max_pixsteps[plane] is relative to the
46 * component in the plane with the max pixel step.
47 * @param max_pixstep_comps an array which is filled with the component
48 * for each plane which has the max pixel step. May be NULL.
50 void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
51 const AVPixFmtDescriptor *pixdesc);
54 * Compute the size of an image line with format pix_fmt and width
55 * width for the plane plane.
57 * @return the computed size in bytes
59 int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane);
62 * Fill plane linesizes for an image with pixel format pix_fmt and
65 * @param linesizes array to be filled with the linesize for each plane
66 * @return >= 0 in case of success, a negative error code otherwise
68 int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width);
71 * Fill plane data pointers for an image with pixel format pix_fmt and
74 * @param data pointers array to be filled with the pointer for each image plane
75 * @param ptr the pointer to a buffer which will contain the image
76 * @param linesizes the array containing the linesize for each
77 * plane, should be filled by av_image_fill_linesizes()
78 * @return the size in bytes required for the image buffer, a negative
79 * error code in case of failure
81 int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int height,
82 uint8_t *ptr, const int linesizes[4]);
85 * Allocate an image with size w and h and pixel format pix_fmt, and
86 * fill pointers and linesizes accordingly.
87 * The allocated image buffer has to be freed by using
88 * av_freep(&pointers[0]).
90 * @param align the value to use for buffer size alignment
91 * @return the size in bytes required for the image buffer, a negative
92 * error code in case of failure
94 int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
95 int w, int h, enum AVPixelFormat pix_fmt, int align);
98 * Copy image plane from src to dst.
99 * That is, copy "height" number of lines of "bytewidth" bytes each.
100 * The first byte of each successive line is separated by *_linesize
103 * @param dst_linesize linesize for the image plane in dst
104 * @param src_linesize linesize for the image plane in src
106 void av_image_copy_plane(uint8_t *dst, int dst_linesize,
107 const uint8_t *src, int src_linesize,
108 int bytewidth, int height);
111 * Copy image in src_data to dst_data.
113 * @param dst_linesizes linesizes for the image in dst_data
114 * @param src_linesizes linesizes for the image in src_data
116 void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
117 const uint8_t *src_data[4], const int src_linesizes[4],
118 enum AVPixelFormat pix_fmt, int width, int height);
121 * Check if the given dimension of an image is valid, meaning that all
122 * bytes of the image can be addressed with a signed int.
124 * @param w the width of the picture
125 * @param h the height of the picture
126 * @param log_offset the offset to sum to the log level for logging with log_ctx
127 * @param log_ctx the parent logging context, it may be NULL
128 * @return >= 0 if valid, a negative error code otherwise
130 int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx);
133 * Check if the given sample aspect ratio of an image is valid.
135 * It is considered invalid if the denominator is 0 or if applying the ratio
136 * to the image size would make the smaller dimension less than 1. If the
137 * sar numerator is 0, it is considered unknown and will return as valid.
139 * @param w width of the image
140 * @param h height of the image
141 * @param sar sample aspect ratio of the image
142 * @return 0 if valid, a negative AVERROR code otherwise
144 int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar);
151 #endif /* AVUTIL_IMGUTILS_H */