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* 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 "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);
/**
* Copy image data located in uncacheable (e.g. GPU mapped) memory. Where
* available, this function will use special functionality for reading from such
* memory, which may result in greatly improved performance compared to plain
* av_image_copy().
*
* The data pointers and the linesizes must be aligned to the maximum required
* by the CPU architecture.
*
* @note The linesize parameters have the type ptrdiff_t here, while they are
* int for av_image_copy().
* @note On x86, the linesizes currently need to be aligned to the cacheline
* size (i.e. 64) to get improved performance.
*/
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);
/**
* 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_linesize 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,
Martin Storsjö
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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 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 assumed linesize alignment
* @return the buffer size in bytes, a negative error code in case of failure
Martin Storsjö
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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_linesize 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],
Martin Storsjö
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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);
/**
* @}
*/