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imgutils.h
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1 /*
2  * This file is part of FFmpeg.
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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  *
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11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
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15  * License along with FFmpeg; if not, write to the Free Software
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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  */
50 void 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  */
68 int 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  */
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  */
94 int 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  */
109 void 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  */
119 void 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  */
137 void 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  */
167 int 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  */
200 int 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  */
214 int 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  */
229 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);
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  */
243 int 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  */
268 int 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 */
int plane
Definition: avisynth_c.h:422
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...
Definition: imgutils.c:76
static enum AVPixelFormat pix_fmt
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
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.
Definition: imgutils.c:452
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...
Definition: imgutils.c:192
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...
Definition: imgutils.c:410
Convenience header that includes libavutil's core.
#define src
Definition: vp8dsp.c:254
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.
Definition: imgutils.c:35
uint8_t
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.
Definition: imgutils.c:287
#define height
AVColorRange
MPEG vs JPEG YUV range.
Definition: pixfmt.h:489
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...
Definition: imgutils.c:430
uint16_t width
Definition: gdv.c:47
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.
Definition: imgutils.c:386
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...
Definition: imgutils.c:282
const AVS_VideoInfo int align
Definition: avisynth_c.h:795
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.
Definition: imgutils.c:111
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
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.
Definition: imgutils.c:89
Rational number (pair of numerator and denominator).
Definition: rational.h:58
Utilties for rational number calculation.
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.
Definition: imgutils.c:402
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...
Definition: imgutils.c:253
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.
Definition: imgutils.c:551
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.
Definition: imgutils.c:338
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60