cosmopolitan/third_party/avir/lanczos1.cc

78 lines
3.8 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

/*-*-mode:c++;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8-*-│
│vi: set net ft=c++ ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program 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 │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/xmmintrin.internal.h"
#include "libc/limits.h"
#include "libc/log/log.h"
#include "libc/runtime/runtime.h"
#include "third_party/avir/lanczos1.h"
namespace {
#include "third_party/avir/lanczos1.hpp"
} // namespace
void lanczos1init(struct lanczos1 *resizer) {
lanczos1free(resizer);
resizer->p = new Lanczos1Impl;
}
void lanczos1free(struct lanczos1 *resizer) {
Lanczos1Impl *impl;
if (!resizer->p) return;
impl = (Lanczos1Impl *)resizer->p;
delete impl;
resizer->p = nullptr;
}
/**
* Resizes image plane w/ Lanczos interpolation, e.g.
*
* struct lanczos1 scaler = {0};
* lanczos1init(&scaler);
* lanczos1(&scaler, ...);
* lanczos1free(&scaler);
*
* @param dyn is destination height
* @param dxn is destination width
* @param dst is destination unsigned char array
* @param dstsize is number of bytes in dst
* @param syn is source height
* @param sxn is source width
* @param ssw is number of unsigned chars per scanline in src
* @param src is source unsigned char array
* @param srcsize is number of bytes in src
*/
void lanczos1(struct lanczos1 *resizer, size_t dyn, size_t dxn, void *dst,
size_t dstsize, size_t syn, size_t sxn, size_t ssw,
const void *src, size_t srcsize) {
Lanczos1Impl *impl;
unsigned int roundhouse;
LOGF("%10s%5zux×%-5zu→%5zu×%-5zu", "lanczos1", sxn, syn, dxn, dyn);
CHECK_LE(dstsize, INT_MAX);
CHECK_LE(srcsize, INT_MAX);
CHECK_LE(sizeof(unsigned char) * 1 * dyn * dxn, dstsize);
CHECK_LE(sizeof(unsigned char) * 1 * syn * sxn, srcsize);
CHECK_LE(sizeof(unsigned char) * syn * ssw, srcsize);
roundhouse = _MM_GET_ROUNDING_MODE();
_MM_SET_ROUNDING_MODE(_MM_ROUND_NEAREST);
impl = (Lanczos1Impl *)resizer->p;
impl->lanczos.resizeImage((const unsigned char *)src, sxn, syn, ssw,
(unsigned char *)dst, dxn, dyn, 1);
_MM_SET_ROUNDING_MODE(roundhouse);
}