You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

108 lines
3.9 KiB

/*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCORE_IMGUTILS_H
#define AVCORE_IMGUTILS_H
/**
* @file
* misc image utilities
*/
#include "libavutil/pixdesc.h"
#include "avcore.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.
*/
static inline void av_fill_image_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
const AVPixFmtDescriptor *pixdesc)
{
int i;
memset(max_pixsteps, 0, 4*sizeof(max_pixsteps[0]));
if (max_pixstep_comps)
memset(max_pixstep_comps, 0, 4*sizeof(max_pixstep_comps[0]));
for (i = 0; i < 4; i++) {
const AVComponentDescriptor *comp = &(pixdesc->comp[i]);
if ((comp->step_minus1+1) > max_pixsteps[comp->plane]) {
max_pixsteps[comp->plane] = comp->step_minus1+1;
if (max_pixstep_comps)
max_pixstep_comps[comp->plane] = i;
}
}
}
/**
* 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_get_image_linesize(enum PixelFormat 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_fill_image_linesizes(int linesizes[4], enum PixelFormat 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[4] the array containing the linesize for each
* plane, should be filled by av_fill_image_linesizes()
* @return the size in bytes required for the image buffer, a negative
* error code in case of failure
*/
int av_fill_image_pointers(uint8_t *data[4], enum PixelFormat pix_fmt, int height,
uint8_t *ptr, const int linesizes[4]);
/**
* 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_check_image_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx);
#endif /* AVCORE_IMGUTILS_H */