FFmpeg 4.2.2
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#include "rational.h"
33
34/**
35 * Compute the max pixel step for each plane of an image with a
36 * format described by pixdesc.
37 *
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
41 * component.
42 *
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.
49 */
50void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
51 const AVPixFmtDescriptor *pixdesc);
52
53/**
54 * Compute the size of an image line with format pix_fmt and width
55 * width for the plane plane.
56 *
57 * @return the computed size in bytes
58 */
60
61/**
62 * Fill plane linesizes for an image with pixel format pix_fmt and
63 * width width.
64 *
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
67 */
68int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width);
69
70/**
71 * Fill plane data pointers for an image with pixel format pix_fmt and
72 * height height.
73 *
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
80 */
81int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int height,
82 uint8_t *ptr, const int linesizes[4]);
83
84/**
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]).
89 *
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
93 */
94int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
95 int w, int h, enum AVPixelFormat pix_fmt, int align);
96
97/**
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
101 * bytes.
102 *
103 * bytewidth must be contained by both absolute values of dst_linesize
104 * and src_linesize, otherwise the function behavior is undefined.
105 *
106 * @param dst_linesize linesize for the image plane in dst
107 * @param src_linesize linesize for the image plane in src
108 */
109void av_image_copy_plane(uint8_t *dst, int dst_linesize,
110 const uint8_t *src, int src_linesize,
111 int bytewidth, int height);
112
113/**
114 * Copy image in src_data to dst_data.
115 *
116 * @param dst_linesizes linesizes for the image in dst_data
117 * @param src_linesizes linesizes for the image in src_data
118 */
119void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4],
120 const uint8_t *src_data[4], const int src_linesizes[4],
121 enum AVPixelFormat pix_fmt, int width, int height);
122
123/**
124 * Copy image data located in uncacheable (e.g. GPU mapped) memory. Where
125 * available, this function will use special functionality for reading from such
126 * memory, which may result in greatly improved performance compared to plain
127 * av_image_copy().
128 *
129 * The data pointers and the linesizes must be aligned to the maximum required
130 * by the CPU architecture.
131 *
132 * @note The linesize parameters have the type ptrdiff_t here, while they are
133 * int for av_image_copy().
134 * @note On x86, the linesizes currently need to be aligned to the cacheline
135 * size (i.e. 64) to get improved performance.
136 */
137void av_image_copy_uc_from(uint8_t *dst_data[4], const ptrdiff_t dst_linesizes[4],
138 const uint8_t *src_data[4], const ptrdiff_t src_linesizes[4],
139 enum AVPixelFormat pix_fmt, int width, int height);
140
141/**
142 * Setup the data pointers and linesizes based on the specified image
143 * parameters and the provided array.
144 *
145 * The fields of the given image are filled in by using the src
146 * address which points to the image data buffer. Depending on the
147 * specified pixel format, one or multiple image data pointers and
148 * line sizes will be set. If a planar format is specified, several
149 * pointers will be set pointing to the different picture planes and
150 * the line sizes of the different planes will be stored in the
151 * lines_sizes array. Call with src == NULL to get the required
152 * size for the src buffer.
153 *
154 * To allocate the buffer and fill in the dst_data and dst_linesize in
155 * one call, use av_image_alloc().
156 *
157 * @param dst_data data pointers to be filled in
158 * @param dst_linesize linesizes for the image in dst_data to be filled in
159 * @param src buffer which will contain or contains the actual image data, can be NULL
160 * @param pix_fmt the pixel format of the image
161 * @param width the width of the image in pixels
162 * @param height the height of the image in pixels
163 * @param align the value used in src for linesize alignment
164 * @return the size in bytes required for src, a negative error code
165 * in case of failure
166 */
167int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4],
168 const uint8_t *src,
169 enum AVPixelFormat pix_fmt, int width, int height, int align);
170
171/**
172 * Return the size in bytes of the amount of data required to store an
173 * image with the given parameters.
174 *
175 * @param pix_fmt the pixel format of the image
176 * @param width the width of the image in pixels
177 * @param height the height of the image in pixels
178 * @param align the assumed linesize alignment
179 * @return the buffer size in bytes, a negative error code in case of failure
180 */
182
183/**
184 * Copy image data from an image into a buffer.
185 *
186 * av_image_get_buffer_size() can be used to compute the required size
187 * for the buffer to fill.
188 *
189 * @param dst a buffer into which picture data will be copied
190 * @param dst_size the size in bytes of dst
191 * @param src_data pointers containing the source image data
192 * @param src_linesize linesizes for the image in src_data
193 * @param pix_fmt the pixel format of the source image
194 * @param width the width of the source image in pixels
195 * @param height the height of the source image in pixels
196 * @param align the assumed linesize alignment for dst
197 * @return the number of bytes written to dst, or a negative value
198 * (error code) on error
199 */
200int av_image_copy_to_buffer(uint8_t *dst, int dst_size,
201 const uint8_t * const src_data[4], const int src_linesize[4],
202 enum AVPixelFormat pix_fmt, int width, int height, int align);
203
204/**
205 * Check if the given dimension of an image is valid, meaning that all
206 * bytes of the image can be addressed with a signed int.
207 *
208 * @param w the width of the picture
209 * @param h the height of the picture
210 * @param log_offset the offset to sum to the log level for logging with log_ctx
211 * @param log_ctx the parent logging context, it may be NULL
212 * @return >= 0 if valid, a negative error code otherwise
213 */
214int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx);
215
216/**
217 * Check if the given dimension of an image is valid, meaning that all
218 * bytes of a plane of an image with the specified pix_fmt can be addressed
219 * with a signed int.
220 *
221 * @param w the width of the picture
222 * @param h the height of the picture
223 * @param max_pixels the maximum number of pixels the user wants to accept
224 * @param pix_fmt the pixel format, can be AV_PIX_FMT_NONE if unknown.
225 * @param log_offset the offset to sum to the log level for logging with log_ctx
226 * @param log_ctx the parent logging context, it may be NULL
227 * @return >= 0 if valid, a negative error code otherwise
228 */
229int av_image_check_size2(unsigned int w, unsigned int h, int64_t max_pixels, enum AVPixelFormat pix_fmt, int log_offset, void *log_ctx);
230
231/**
232 * Check if the given sample aspect ratio of an image is valid.
233 *
234 * It is considered invalid if the denominator is 0 or if applying the ratio
235 * to the image size would make the smaller dimension less than 1. If the
236 * sar numerator is 0, it is considered unknown and will return as valid.
237 *
238 * @param w width of the image
239 * @param h height of the image
240 * @param sar sample aspect ratio of the image
241 * @return 0 if valid, a negative AVERROR code otherwise
242 */
243int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar);
244
245/**
246 * Overwrite the image data with black. This is suitable for filling a
247 * sub-rectangle of an image, meaning the padding between the right most pixel
248 * and the left most pixel on the next line will not be overwritten. For some
249 * formats, the image size might be rounded up due to inherent alignment.
250 *
251 * If the pixel format has alpha, the alpha is cleared to opaque.
252 *
253 * This can return an error if the pixel format is not supported. Normally, all
254 * non-hwaccel pixel formats should be supported.
255 *
256 * Passing NULL for dst_data is allowed. Then the function returns whether the
257 * operation would have succeeded. (It can return an error if the pix_fmt is
258 * not supported.)
259 *
260 * @param dst_data data pointers to destination image
261 * @param dst_linesize linesizes for the destination image
262 * @param pix_fmt the pixel format of the image
263 * @param range the color range of the image (important for colorspaces such as YUV)
264 * @param width the width of the image in pixels
265 * @param height the height of the image in pixels
266 * @return 0 if the image data was cleared, a negative AVERROR code otherwise
267 */
268int av_image_fill_black(uint8_t *dst_data[4], const ptrdiff_t dst_linesize[4],
269 enum AVPixelFormat pix_fmt, enum AVColorRange range,
270 int width, int height);
271
272/**
273 * @}
274 */
275
276
277#endif /* AVUTIL_IMGUTILS_H */
Convenience header that includes libavutil's core.
static int width
static enum AVPixelFormat pix_fmt
static int height
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters.
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int height, uint8_t *ptr, const int linesizes[4])
Fill plane data pointers for an image with pixel format pix_fmt and height height.
int av_image_fill_black(uint8_t *dst_data[4], const ptrdiff_t dst_linesize[4], enum AVPixelFormat pix_fmt, enum AVColorRange range, int width, int height)
Overwrite the image data with black.
int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4], const uint8_t *src, enum AVPixelFormat pix_fmt, int width, int height, int align)
Setup the data pointers and linesizes based on the specified image parameters and the provided array.
void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4], const uint8_t *src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Copy image in src_data to dst_data.
int av_image_copy_to_buffer(uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
Copy image data from an image into a buffer.
void av_image_copy_plane(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height)
Copy image plane from src to dst.
int av_image_alloc(uint8_t *pointers[4], int linesizes[4], int w, int h, enum AVPixelFormat pix_fmt, int align)
Allocate an image with size w and h and pixel format pix_fmt, and fill pointers and linesizes accordi...
void av_image_copy_uc_from(uint8_t *dst_data[4], const ptrdiff_t dst_linesizes[4], const uint8_t *src_data[4], const ptrdiff_t src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Copy image data located in uncacheable (e.g.
int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane)
Compute the size of an image line with format pix_fmt and width width for the plane plane.
int av_image_check_size2(unsigned int w, unsigned int h, int64_t max_pixels, enum AVPixelFormat pix_fmt, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of a plane of an image with...
int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width)
Fill plane linesizes for an image with pixel format pix_fmt and width width.
void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4], const AVPixFmtDescriptor *pixdesc)
Compute the max pixel step for each plane of an image with a format described by pixdesc.
int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar)
Check if the given sample aspect ratio of an image is valid.
AVColorRange
MPEG vs JPEG YUV range.
Definition: pixfmt.h:519
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
Utilties for rational number calculation.
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
Rational number (pair of numerator and denominator).
Definition: rational.h:58