cosmopolitan/tool/viz/lib/bilinearscale.c

102 lines
5.0 KiB
C

/*-*- 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 "dsp/core/twixt8.h"
#include "libc/log/check.h"
#include "libc/log/log.h"
#include "libc/macros.h"
#include "libc/math.h"
#include "libc/mem/mem.h"
#include "libc/nexgen32e/bsr.h"
#include "libc/runtime/gc.h"
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
#include "libc/testlib/testlib.h"
#include "libc/tinymath/emod.h"
#include "libc/x/x.h"
#include "tool/viz/lib/bilinearscale.h"
static void ComputeScalingSolution(long dn, long sn, double r, double o,
unsigned char pct[dn + 1], int idx[dn + 1]) {
long i;
double x;
o -= .5;
o += (r - 1) / 2;
for (i = 0; i < dn + 1; ++i) {
x = o + i * r;
idx[i] = MIN(sn - 1, MAX(0, lround(x)));
pct[i] = lround((x - idx[i]) * 255) % 256;
}
}
static void BilinearScaler(long dcw, long dyw, long dxw,
unsigned char dst[dcw][dyw][dxw], long scw, long syw,
long sxw, const unsigned char src[scw][syw][sxw],
long c0, long cn, long dyn, long dxn, long syn,
long sxn, double ry, double rx, double oy, double ox,
int iy[dyn + 1], unsigned char py[dyn + 1],
int ix[dxn + 1], unsigned char px[dxn + 1],
unsigned char db[dxn], unsigned char sb[2][sxn]) {
long c, y, x, b;
ComputeScalingSolution(dxn, sxn, rx, ox, px, ix);
ComputeScalingSolution(dyn, syn, ry, oy, py, iy);
for (c = c0; c < cn; ++c) {
for (y = 0; y < dyn; ++y) {
memcpy(sb[0], src[c][iy[y + 0]], sxn);
memcpy(sb[1], src[c][iy[y + 1]], sxn);
for (x = 0; x < dxn; ++x) {
db[x] = twixt8(twixt8(sb[0][ix[x]], sb[0][ix[x + 1]], px[x]),
twixt8(sb[1][ix[x]], sb[1][ix[x + 1]], px[x]), py[y]);
}
memcpy(dst[c][y], db, dxn);
}
}
}
void *BilinearScale(long dcw, long dyw, long dxw,
unsigned char dst[dcw][dyw][dxw], long scw, long syw,
long sxw, const unsigned char src[scw][syw][sxw], long c0,
long cn, long dyn, long dxn, long syn, long sxn, double ry,
double rx, double oy, double ox) {
if (dyn > 0 && dxn > 0) {
if (syn > 0 && sxn > 0) {
DCHECK_LE(c0, cn);
DCHECK_LE(cn, scw);
DCHECK_LE(cn, dcw);
DCHECK_LE(syn, syw);
DCHECK_LE(sxn, sxw);
DCHECK_LE(dyn, dyw);
DCHECK_LE(dxn, dxw);
DCHECK_LT(bsrl(cn) + bsrl(syn) + bsrl(sxn), 32);
DCHECK_LT(bsrl(cn) + bsrl(dyn) + bsrl(dxn), 32);
BilinearScaler(dcw, dyw, dxw, dst, scw, syw, sxw, src, c0, cn, dyn, dxn,
syn, sxn, ry, rx, oy, ox,
gc(xmemalign(64, ROUNDUP(sizeof(int) * (dyn + 1), 64))),
gc(xmemalign(64, ROUNDUP(dyn + 1, 64))),
gc(xmemalign(64, ROUNDUP(sizeof(int) * (dxn + 1), 64))),
gc(xmemalign(64, ROUNDUP(dxn + 1, 64))),
gc(xmemalign(64, ROUNDUP(dxn, 64))),
gc(xmemalign(64, ROUNDUP(sxn, 64) * 2)));
} else {
memset(dst[c0], 0, &dst[cn][0][0] - &dst[c0][0][0]);
}
}
return dst;
}