/* * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVUTIL_IMGUTILS_H #define AVUTIL_IMGUTILS_H /** * @file * misc image utilities * * @addtogroup lavu_picture * @{ */ #include "avutil.h" #include "pixdesc.h" #include "rational.h" /** * Compute the max pixel step for each plane of an image with a * format described by pixdesc. * * The pixel step is the distance in bytes between the first byte of * the group of bytes which describe a pixel component and the first * byte of the successive group in the same plane for the same * component. * * @param max_pixsteps an array which is filled with the max pixel step * for each plane. Since a plane may contain different pixel * components, the computed max_pixsteps[plane] is relative to the * component in the plane with the max pixel step. * @param max_pixstep_comps an array which is filled with the component * for each plane which has the max pixel step. May be NULL. */ void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4], const AVPixFmtDescriptor *pixdesc); /** * Compute the size of an image line with format pix_fmt and width * width for the plane plane. * * @return the computed size in bytes */ int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane); /** * Fill plane linesizes for an image with pixel format pix_fmt and * width width. * * @param linesizes array to be filled with the linesize for each plane * @return >= 0 in case of success, a negative error code otherwise */ int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width); /** * Fill plane data pointers for an image with pixel format pix_fmt and * height height. * * @param data pointers array to be filled with the pointer for each image plane * @param ptr the pointer to a buffer which will contain the image * @param linesizes the array containing the linesize for each * plane, should be filled by av_image_fill_linesizes() * @return the size in bytes required for the image buffer, a negative * error code in case of failure */ int av_image_fill_pointers(uint8_t *data[4], enum AVPixelFormat pix_fmt, int height, uint8_t *ptr, const int linesizes[4]); /** * Allocate an image with size w and h and pixel format pix_fmt, and * fill pointers and linesizes accordingly. * The allocated image buffer has to be freed by using * av_freep(&pointers[0]). * * @param align the value to use for buffer size alignment * @return the size in bytes required for the image buffer, a negative * error code in case of failure */ int av_image_alloc(uint8_t *pointers[4], int linesizes[4], int w, int h, enum AVPixelFormat pix_fmt, int align); /** * Copy image plane from src to dst. * That is, copy "height" number of lines of "bytewidth" bytes each. * The first byte of each successive line is separated by *_linesize * bytes. * * @param dst_linesize linesize for the image plane in dst * @param src_linesize linesize for the image plane in src */ void av_image_copy_plane(uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize, int bytewidth, int height); /** * Copy image in src_data to dst_data. * * @param dst_linesizes linesizes for the image in dst_data * @param src_linesizes linesizes for the image in src_data */ 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); /** * Setup the data pointers and linesizes based on the specified image * parameters and the provided array. * * The fields of the given image are filled in by using the src * address which points to the image data buffer. Depending on the * specified pixel format, one or multiple image data pointers and * line sizes will be set. If a planar format is specified, several * pointers will be set pointing to the different picture planes and * the line sizes of the different planes will be stored in the * lines_sizes array. Call with src == NULL to get the required * size for the src buffer. * * To allocate the buffer and fill in the dst_data and dst_linesize in * one call, use av_image_alloc(). * * @param dst_data data pointers to be filled in * @param dst_linesizes linesizes for the image in dst_data to be filled in * @param src buffer which will contain or contains the actual image data, can be NULL * @param pix_fmt the pixel format of the image * @param width the width of the image in pixels * @param height the height of the image in pixels * @param align the value used in src for linesize alignment * @return the size in bytes required for src, a negative error code * in case of failure */ 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); /** * Return the size in bytes of the amount of data required to store an * image with the given parameters. * * @param[in] align the assumed linesize alignment */ int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align); /** * Copy image data from an image into a buffer. * * av_image_get_buffer_size() can be used to compute the required size * for the buffer to fill. * * @param dst a buffer into which picture data will be copied * @param dst_size the size in bytes of dst * @param src_data pointers containing the source image data * @param src_linesizes linesizes for the image in src_data * @param pix_fmt the pixel format of the source image * @param width the width of the source image in pixels * @param height the height of the source image in pixels * @param align the assumed linesize alignment for dst * @return the number of bytes written to dst, or a negative value * (error code) on error */ 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); /** * Check if the given dimension of an image is valid, meaning that all * bytes of the image can be addressed with a signed int. * * @param w the width of the picture * @param h the height of the picture * @param log_offset the offset to sum to the log level for logging with log_ctx * @param log_ctx the parent logging context, it may be NULL * @return >= 0 if valid, a negative error code otherwise */ int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx); /** * Check if the given sample aspect ratio of an image is valid. * * It is considered invalid if the denominator is 0 or if applying the ratio * to the image size would make the smaller dimension less than 1. If the * sar numerator is 0, it is considered unknown and will return as valid. * * @param w width of the image * @param h height of the image * @param sar sample aspect ratio of the image * @return 0 if valid, a negative AVERROR code otherwise */ int av_image_check_sar(unsigned int w, unsigned int h, AVRational sar); /** * @} */ #endif /* AVUTIL_IMGUTILS_H */