libtthimage/Lib/calcluts.c

120 lines
2.1 KiB
C

/*
calcluts.c
----------
voir aussi: luts15bits.c
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef NEED_ALLOCA_H
#include <alloca.h>
#endif
#include "tthimage.h"
/*::------------------------------------------------------------------::*/
int
Image_calclut_lin(int *lut, int v0, int v255)
{
int foo, quux, delta;
#if DEBUG_LEVEL
fprintf(stderr, "calclut lin: v0 = %d v255 = %d\n", v0, v255);
#endif
delta = v255 - v0;
if (delta == 0)
{
return DIVISOR_IS_0;
}
#if DEBUG_LEVEL
fprintf(stderr, "calclut lin: delta = %d\n", delta);
#endif
for (foo=0; foo<256; foo++)
{
quux = (foo * delta / 255) + v0;
#if DEBUG_LEVEL
printf("lut(%d) = %d\n", foo, quux);
#endif
lut[foo] = quux;
}
return FUNC_IS_ALPHA;
}
/*::------------------------------------------------------------------::*/
int
Image_calclut_foo(int *lut, int v0, int v255)
{
fprintf(stderr, "%s ( %p %d %d )\n", __func__, lut, v0, v255);
return FUNC_IS_ALPHA;
}
/*::------------------------------------------------------------------::*/
int
Image_print_lut(int *lut, char *fname, int flag)
{
FILE *fp;
int foo;
if (strcmp(fname, "-"))
fp = fopen(fname, "w");
else
fp = stdout;
for (foo=0; foo<256; foo++)
{
if (flag)
printf("%d ", foo);
printf("%d\n", lut[foo]);
}
if (fp!=stdout)
fclose(fp);
return FUNC_IS_ALPHA;
}
/*::------------------------------------------------------------------::*/
int
Image_load_lut(int *lut, char *fname, int flag)
{
FILE *fp;
int value, foo, idx;
if (flag) {
fprintf(stderr, "in %s, flag must be O, was %d\n", __func__, flag);
return WRONG_FLAG;
}
#if DEBUG_LEVEL
fprintf(stderr, "load_lut %s in %p\n", fname, lut);
#endif
if (NULL==(fp=fopen(fname, "r")))
{
fprintf(stderr, "%s can't fopen %s\n", __func__, fname);
return 666;
}
/* WARNING : very crude code here (4 nov 1999) */
for (idx=0; idx<256; idx++)
{
foo = fscanf(fp, "%d", &value);
#if DEBUG_LEVEL
fprintf(stderr, "load lut %3d %3d %d\n", idx, foo, value);
#endif
if (1==foo) lut[idx] = value;
else lut[idx] = -1;
}
fclose(fp);
return FUNC_IS_ALPHA;
}
/*::------------------------------------------------------------------::*/