ffmpeg/libavutil/spherical.c

53 lines
2.0 KiB
C

/*
* Copyright (c) 2016 Vittorio Giovara <vittorio.giovara@gmail.com>
*
* 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
*/
#include "mem.h"
#include "spherical.h"
AVSphericalMapping *av_spherical_alloc(size_t *size)
{
AVSphericalMapping *spherical = av_mallocz(sizeof(AVSphericalMapping));
if (!spherical)
return NULL;
if (size)
*size = sizeof(*spherical);
return spherical;
}
void av_spherical_tile_bounds(const AVSphericalMapping *map,
size_t width, size_t height,
size_t *left, size_t *top,
size_t *right, size_t *bottom)
{
/* conversion from 0.32 coordinates to pixels */
uint64_t orig_width = (uint64_t) width * UINT32_MAX /
(UINT32_MAX - map->bound_right - map->bound_left);
uint64_t orig_height = (uint64_t) height * UINT32_MAX /
(UINT32_MAX - map->bound_bottom - map->bound_top);
/* add a (UINT32_MAX - 1) to round up integer division */
*left = (orig_width * map->bound_left + UINT32_MAX - 1) / UINT32_MAX;
*top = (orig_height * map->bound_top + UINT32_MAX - 1) / UINT32_MAX;
*right = orig_width - width - *left;
*bottom = orig_height - height - *top;
}