PeerStreamer

/*

 * 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_pixstep an array which is filled with the max pixel step

 * for each plane. Since a plane may contain different pixel

 * components, the computed max_pixstep[plane] is relative to the

 * component in the plane with the max pixel step.

 * @param max_pixstep_comp 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_pixstep(int max_pixstep[4], int max_pixstep_comp[4],

                                             const AVPixFmtDescriptor *pixdesc)

{

    int i;

    memset(max_pixstep, 0, 4*sizeof(max_pixstep[0]));

    if (max_pixstep_comp)

        memset(max_pixstep_comp, 0, 4*sizeof(max_pixstep_comp[0]));

    for (i = 0; i < 4; i++) {

        const AVComponentDescriptor *comp = &(pixdesc->comp[i]);

        if ((comp->step_minus1+1) > max_pixstep[comp->plane]) {

            max_pixstep[comp->plane] = comp->step_minus1+1;

            if (max_pixstep_comp)

                max_pixstep_comp[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 */