Pillow/libImaging/Point.c
2010-07-30 22:52:47 -04:00

264 lines
7.1 KiB
C

/*
* The Python Imaging Library
* $Id$
*
* point (pixel) translation
*
* history:
* 1995-11-27 fl Created
* 1996-03-31 fl Fixed colour support
* 1996-08-13 fl Support 8-bit to "1" thresholding
* 1997-05-31 fl Added floating point transform
* 1998-07-02 fl Added integer point transform
* 1998-07-17 fl Support L to anything lookup
* 2004-12-18 fl Refactored; added I to L lookup
*
* Copyright (c) 1997-2004 by Secret Labs AB.
* Copyright (c) 1995-2004 by Fredrik Lundh.
*
* See the README file for information on usage and redistribution.
*/
#include "Imaging.h"
typedef struct {
const void* table;
} im_point_context;
static void
im_point_8_8(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 8-bit source, 8-bit destination */
UINT8* table = (UINT8*) context->table;
for (y = 0; y < imIn->ysize; y++) {
UINT8* in = imIn->image8[y];
UINT8* out = imOut->image8[y];
for (x = 0; x < imIn->xsize; x++)
out[x] = table[in[x]];
}
}
static void
im_point_2x8_2x8(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 2x8-bit source, 2x8-bit destination */
UINT8* table = (UINT8*) context->table;
for (y = 0; y < imIn->ysize; y++) {
UINT8* in = (UINT8*) imIn->image[y];
UINT8* out = (UINT8*) imOut->image[y];
for (x = 0; x < imIn->xsize; x++) {
out[0] = table[in[0]];
out[3] = table[in[3]+256];
in += 4; out += 4;
}
}
}
static void
im_point_3x8_3x8(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 3x8-bit source, 3x8-bit destination */
UINT8* table = (UINT8*) context->table;
for (y = 0; y < imIn->ysize; y++) {
UINT8* in = (UINT8*) imIn->image[y];
UINT8* out = (UINT8*) imOut->image[y];
for (x = 0; x < imIn->xsize; x++) {
out[0] = table[in[0]];
out[1] = table[in[1]+256];
out[2] = table[in[2]+512];
in += 4; out += 4;
}
}
}
static void
im_point_4x8_4x8(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 4x8-bit source, 4x8-bit destination */
UINT8* table = (UINT8*) context->table;
for (y = 0; y < imIn->ysize; y++) {
UINT8* in = (UINT8*) imIn->image[y];
UINT8* out = (UINT8*) imOut->image[y];
for (x = 0; x < imIn->xsize; x++) {
out[0] = table[in[0]];
out[1] = table[in[1]+256];
out[2] = table[in[2]+512];
out[3] = table[in[3]+768];
in += 4; out += 4;
}
}
}
static void
im_point_8_32(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 8-bit source, 32-bit destination */
INT32* table = (INT32*) context->table;
for (y = 0; y < imIn->ysize; y++) {
UINT8* in = imIn->image8[y];
INT32* out = imOut->image32[y];
for (x = 0; x < imIn->xsize; x++)
out[x] = table[in[x]];
}
}
static void
im_point_32_8(Imaging imOut, Imaging imIn, im_point_context* context)
{
int x, y;
/* 32-bit source, 8-bit destination */
UINT8* table = (UINT8*) context->table;
for (y = 0; y < imIn->ysize; y++) {
INT32* in = imIn->image32[y];
UINT8* out = imOut->image8[y];
for (x = 0; x < imIn->xsize; x++) {
int v = in[x];
if (v < 0)
v = 0;
else if (v > 65535)
v = 65535;
out[x] = table[v];
}
}
}
Imaging
ImagingPoint(Imaging imIn, const char* mode, const void* table)
{
/* lookup table transform */
ImagingSectionCookie cookie;
Imaging imOut;
im_point_context context;
void (*point)(Imaging imIn, Imaging imOut, im_point_context* context);
if (!imIn)
return (Imaging) ImagingError_ModeError();
if (!mode)
mode = imIn->mode;
if (imIn->type != IMAGING_TYPE_UINT8) {
if (imIn->type != IMAGING_TYPE_INT32 || strcmp(mode, "L") != 0)
goto mode_mismatch;
} else if (!imIn->image8 && strcmp(imIn->mode, mode) != 0)
goto mode_mismatch;
imOut = ImagingNew(mode, imIn->xsize, imIn->ysize);
if (!imOut)
return NULL;
/* find appropriate handler */
if (imIn->type == IMAGING_TYPE_UINT8) {
if (imIn->bands == imOut->bands && imIn->type == imOut->type) {
switch (imIn->bands) {
case 1:
point = im_point_8_8;
break;
case 2:
point = im_point_2x8_2x8;
break;
case 3:
point = im_point_3x8_3x8;
break;
case 4:
point = im_point_4x8_4x8;
break;
default:
/* this cannot really happen */
point = im_point_8_8;
break;
}
} else
point = im_point_8_32;
} else
point = im_point_32_8;
ImagingCopyInfo(imOut, imIn);
ImagingSectionEnter(&cookie);
context.table = table;
point(imOut, imIn, &context);
ImagingSectionLeave(&cookie);
return imOut;
mode_mismatch:
return (Imaging) ImagingError_ValueError(
"point operation not supported for this mode"
);
}
Imaging
ImagingPointTransform(Imaging imIn, double scale, double offset)
{
/* scale/offset transform */
ImagingSectionCookie cookie;
Imaging imOut;
int x, y;
if (!imIn || (strcmp(imIn->mode, "I") != 0 &&
strcmp(imIn->mode, "I;16") != 0 &&
strcmp(imIn->mode, "F") != 0))
return (Imaging) ImagingError_ModeError();
imOut = ImagingNew(imIn->mode, imIn->xsize, imIn->ysize);
if (!imOut)
return NULL;
ImagingCopyInfo(imOut, imIn);
switch (imIn->type) {
case IMAGING_TYPE_INT32:
ImagingSectionEnter(&cookie);
for (y = 0; y < imIn->ysize; y++) {
INT32* in = imIn->image32[y];
INT32* out = imOut->image32[y];
/* FIXME: add clipping? */
for (x = 0; x < imIn->xsize; x++)
out[x] = in[x] * scale + offset;
}
ImagingSectionLeave(&cookie);
break;
case IMAGING_TYPE_FLOAT32:
ImagingSectionEnter(&cookie);
for (y = 0; y < imIn->ysize; y++) {
FLOAT32* in = (FLOAT32*) imIn->image32[y];
FLOAT32* out = (FLOAT32*) imOut->image32[y];
for (x = 0; x < imIn->xsize; x++)
out[x] = in[x] * scale + offset;
}
ImagingSectionLeave(&cookie);
break;
case IMAGING_TYPE_SPECIAL:
if (strcmp(imIn->mode,"I;16") == 0) {
ImagingSectionEnter(&cookie);
for (y = 0; y < imIn->ysize; y++) {
UINT16* in = (UINT16 *)imIn->image[y];
UINT16* out = (UINT16 *)imOut->image[y];
/* FIXME: add clipping? */
for (x = 0; x < imIn->xsize; x++)
out[x] = in[x] * scale + offset;
}
ImagingSectionLeave(&cookie);
break;
}
/* FALL THROUGH */
default:
ImagingDelete(imOut);
return (Imaging) ImagingError_ValueError("internal error");
}
return imOut;
}