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 */ 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 */ 59 int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane); 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 */ 81 int 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 */ 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 * Setup the data pointers and linesizes based on the specified image 125 * parameters and the provided array. 126 * 127 * The fields of the given image are filled in by using the src 128 * address which points to the image data buffer. Depending on the 129 * specified pixel format, one or multiple image data pointers and 130 * line sizes will be set. If a planar format is specified, several 131 * pointers will be set pointing to the different picture planes and 132 * the line sizes of the different planes will be stored in the 133 * lines_sizes array. Call with !src to get the required 134 * size for the src buffer. 135 * 136 * To allocate the buffer and fill in the dst_data and dst_linesize in 137 * one call, use av_image_alloc(). 138 * 139 * @param dst_data data pointers to be filled in 140 * @param dst_linesizes linesizes for the image in dst_data to be filled in 141 * @param src buffer which will contain or contains the actual image data, can be NULL 142 * @param pix_fmt the pixel format of the image 143 * @param width the width of the image in pixels 144 * @param height the height of the image in pixels 145 * @param align the value used in src for linesize alignment 146 * @return the size in bytes required for src, a negative error code 147 * in case of failure 148 */ 149 int av_image_fill_arrays(uint8_t *dst_data[4], int dst_linesize[4], 150 const uint8_t *src, 151 enum AVPixelFormat pix_fmt, int width, int height, int align); 152 153 /** 154 * Return the size in bytes of the amount of data required to store an 155 * image with the given parameters. 156 * 157 * @param[in] align the assumed linesize alignment 158 */ 159 int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align); 160 161 /** 162 * Copy image data from an image into a buffer. 163 * 164 * av_image_get_buffer_size() can be used to compute the required size 165 * for the buffer to fill. 166 * 167 * @param dst a buffer into which picture data will be copied 168 * @param dst_size the size in bytes of dst 169 * @param src_data pointers containing the source image data 170 * @param src_linesizes linesizes for the image in src_data 171 * @param pix_fmt the pixel format of the source image 172 * @param width the width of the source image in pixels 173 * @param height the height of the source image in pixels 174 * @param align the assumed linesize alignment for dst 175 * @return the number of bytes written to dst, or a negative value 176 * (error code) on error 177 */ 178 int av_image_copy_to_buffer(uint8_t *dst, int dst_size, 179 const uint8_t * const src_data[4], const int src_linesize[4], 180 enum AVPixelFormat pix_fmt, int width, int height, int align); 181 182 /** 183 * Check if the given dimension of an image is valid, meaning that all 184 * bytes of the image can be addressed with a signed int. 185 * 186 * @param w the width of the picture 187 * @param h the height of the picture 188 * @param log_offset the offset to sum to the log level for logging with log_ctx 189 * @param log_ctx the parent logging context, it may be NULL 190 * @return >= 0 if valid, a negative error code otherwise 191 */ 192 int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx); 193 194 /** 195 * Check if the given sample aspect ratio of an image is valid. 196 * 197 * It is considered invalid if the denominator is 0 or if applying the ratio 198 * to the image size would make the smaller dimension less than 1. If the 199 * sar numerator is 0, it is considered unknown and will return as valid. 200 * 201 * @param w width of the image 202 * @param h height of the image 203 * @param sar sample aspect ratio of the image 204 * @return 0 if valid, a negative AVERROR code otherwise 205 */ 206 int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar); 207 208 /** 209 * @} 210 */ 211 212 213 #endif /* AVUTIL_IMGUTILS_H */ 214