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imgutils.h
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg 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.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
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.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVUTIL_IMGUTILS_H
20 #define AVUTIL_IMGUTILS_H
21 
22 /**
23  * @file
24  * misc image utilities
25  *
26  * @addtogroup lavu_picture
27  * @{
28  */
29 
30 #include "avutil.h"
31 #include "pixdesc.h"
32 
33 /**
34  * Compute the max pixel step for each plane of an image with a
35  * format described by pixdesc.
36  *
37  * The pixel step is the distance in bytes between the first byte of
38  * the group of bytes which describe a pixel component and the first
39  * byte of the successive group in the same plane for the same
40  * component.
41  *
42  * @param max_pixsteps an array which is filled with the max pixel step
43  * for each plane. Since a plane may contain different pixel
44  * components, the computed max_pixsteps[plane] is relative to the
45  * component in the plane with the max pixel step.
46  * @param max_pixstep_comps an array which is filled with the component
47  * for each plane which has the max pixel step. May be NULL.
48  */
49 void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
50  const AVPixFmtDescriptor *pixdesc);
51 
52 /**
53  * Compute the size of an image line with format pix_fmt and width
54  * width for the plane plane.
55  *
56  * @return the computed size in bytes
57  */
58 int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane);
59 
60 /**
61  * Fill plane linesizes for an image with pixel format pix_fmt and
62  * width width.
63  *
64  * @param linesizes array to be filled with the linesize for each plane
65  * @return >= 0 in case of success, a negative error code otherwise
66  */
67 int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width);
68 
69 /**
70  * Fill plane data pointers for an image with pixel format pix_fmt and
71  * height height.
72  *
73  * @param data pointers array to be filled with the pointer for each image plane
74  * @param ptr the pointer to a buffer which will contain the image
75  * @param linesizes the array containing the linesize for each
76  * plane, should be filled by av_image_fill_linesizes()
77  * @return the size in bytes required for the image buffer, a negative
78  * error code in case of failure
79  */
81  uint8_t *ptr, const int linesizes[4]);
82 
83 /**
84  * Allocate an image with size w and h and pixel format pix_fmt, and
85  * fill pointers and linesizes accordingly.
86  * The allocated image buffer has to be freed by using
87  * av_freep(&pointers[0]).
88  *
89  * @param align the value to use for buffer size alignment
90  * @return the size in bytes required for the image buffer, a negative
91  * error code in case of failure
92  */
93 int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
94  int w, int h, enum AVPixelFormat pix_fmt, int align);
95 
96 /**
97  * Copy image plane from src to dst.
98  * That is, copy "height" number of lines of "bytewidth" bytes each.
99  * The first byte of each successive line is separated by *_linesize
100  * bytes.
101  *
102  * bytewidth must be contained by both absolute values of dst_linesize
103  * and src_linesize, otherwise the function behavior is undefined.
104  *
105  * @param dst_linesize linesize for the image plane in dst
106  * @param src_linesize linesize for the image plane in src
107  */
108 void av_image_copy_plane(uint8_t *dst, int dst_linesize,
109  const uint8_t *src, int src_linesize,
110  int bytewidth, int height);
111 
112 /**
113  * Copy image in src_data to dst_data.
114  *
115  * @param dst_linesizes linesizes for the image in dst_data
116  * @param src_linesizes linesizes for the image in src_data
117  */
118 void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
119  const uint8_t *src_data[4], const int src_linesizes[4],
120  enum AVPixelFormat pix_fmt, int width, int height);
121 
122 /**
123  * Setup the data pointers and linesizes based on the specified image
124  * parameters and the provided array.
125  *
126  * The fields of the given image are filled in by using the src
127  * address which points to the image data buffer. Depending on the
128  * specified pixel format, one or multiple image data pointers and
129  * line sizes will be set. If a planar format is specified, several
130  * pointers will be set pointing to the different picture planes and
131  * the line sizes of the different planes will be stored in the
132  * lines_sizes array. Call with src == NULL to get the required
133  * size for the src buffer.
134  *
135  * To allocate the buffer and fill in the dst_data and dst_linesize in
136  * one call, use av_image_alloc().
137  *
138  * @param dst_data data pointers to be filled in
139  * @param dst_linesizes linesizes for the image in dst_data to be filled in
140  * @param src buffer which will contain or contains the actual image data, can be NULL
141  * @param pix_fmt the pixel format of the image
142  * @param width the width of the image in pixels
143  * @param height the height of the image in pixels
144  * @param align the value used in src for linesize alignment
145  * @return the size in bytes required for src, a negative error code
146  * in case of failure
147  */
148 int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4],
149  const uint8_t *src,
150  enum AVPixelFormat pix_fmt, int width, int height, int align);
151 
152 /**
153  * Return the size in bytes of the amount of data required to store an
154  * image with the given parameters.
155  *
156  * @param[in] align the assumed linesize alignment
157  */
158 int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align);
159 
160 /**
161  * Copy image data from an image into a buffer.
162  *
163  * av_image_get_buffer_size() can be used to compute the required size
164  * for the buffer to fill.
165  *
166  * @param dst a buffer into which picture data will be copied
167  * @param dst_size the size in bytes of dst
168  * @param src_data pointers containing the source image data
169  * @param src_linesizes linesizes for the image in src_data
170  * @param pix_fmt the pixel format of the source image
171  * @param width the width of the source image in pixels
172  * @param height the height of the source image in pixels
173  * @param align the assumed linesize alignment for dst
174  * @return the number of bytes written to dst, or a negative value
175  * (error code) on error
176  */
177 int av_image_copy_to_buffer(uint8_t *dst, int dst_size,
178  const uint8_t * const src_data[4], const int src_linesize[4],
179  enum AVPixelFormat pix_fmt, int width, int height, int align);
180 
181 /**
182  * Check if the given dimension of an image is valid, meaning that all
183  * bytes of the image can be addressed with a signed int.
184  *
185  * @param w the width of the picture
186  * @param h the height of the picture
187  * @param log_offset the offset to sum to the log level for logging with log_ctx
188  * @param log_ctx the parent logging context, it may be NULL
189  * @return >= 0 if valid, a negative error code otherwise
190  */
191 int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx);
192 
193 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
194 
195 /**
196  * @}
197  */
198 
199 
200 #endif /* AVUTIL_IMGUTILS_H */