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130 lines
3.0 KiB
C
130 lines
3.0 KiB
C
/*
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* The Python Imaging Library
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* $Id$
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*
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* stuff to extract and paste back individual bands
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*
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* history:
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* 1996-03-20 fl Created
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* 1997-08-27 fl Fixed putband for single band targets.
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* 2003-09-26 fl Fixed getband/putband for 2-band images (LA, PA).
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*
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* Copyright (c) 1997-2003 by Secret Labs AB.
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* Copyright (c) 1996-1997 by Fredrik Lundh.
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*
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* See the README file for details on usage and redistribution.
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*/
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#include "Imaging.h"
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#define CLIP(x) ((x) <= 0 ? 0 : (x) < 256 ? (x) : 255)
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Imaging
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ImagingGetBand(Imaging imIn, int band)
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{
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Imaging imOut;
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int x, y;
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/* Check arguments */
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if (!imIn || imIn->type != IMAGING_TYPE_UINT8)
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return (Imaging) ImagingError_ModeError();
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if (band < 0 || band >= imIn->bands)
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return (Imaging) ImagingError_ValueError("band index out of range");
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/* Shortcuts */
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if (imIn->bands == 1)
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return ImagingCopy(imIn);
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/* Special case for LXXA etc */
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if (imIn->bands == 2 && band == 1)
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band = 3;
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imOut = ImagingNew("L", imIn->xsize, imIn->ysize);
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if (!imOut)
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return NULL;
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/* Extract band from image */
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for (y = 0; y < imIn->ysize; y++) {
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UINT8* in = (UINT8*) imIn->image[y] + band;
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UINT8* out = imOut->image8[y];
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for (x = 0; x < imIn->xsize; x++) {
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out[x] = *in;
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in += 4;
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}
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}
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return imOut;
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}
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Imaging
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ImagingPutBand(Imaging imOut, Imaging imIn, int band)
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{
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int x, y;
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/* Check arguments */
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if (!imIn || imIn->bands != 1 || !imOut)
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return (Imaging) ImagingError_ModeError();
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if (band < 0 || band >= imOut->bands)
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return (Imaging) ImagingError_ValueError("band index out of range");
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if (imIn->type != imOut->type ||
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imIn->xsize != imOut->xsize ||
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imIn->ysize != imOut->ysize)
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return (Imaging) ImagingError_Mismatch();
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/* Shortcuts */
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if (imOut->bands == 1)
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return ImagingCopy2(imOut, imIn);
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/* Special case for LXXA etc */
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if (imOut->bands == 2 && band == 1)
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band = 3;
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/* Insert band into image */
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for (y = 0; y < imIn->ysize; y++) {
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UINT8* in = imIn->image8[y];
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UINT8* out = (UINT8*) imOut->image[y] + band;
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for (x = 0; x < imIn->xsize; x++) {
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*out = in[x];
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out += 4;
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}
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}
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return imOut;
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}
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Imaging
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ImagingFillBand(Imaging imOut, int band, int color)
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{
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int x, y;
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/* Check arguments */
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if (!imOut || imOut->type != IMAGING_TYPE_UINT8)
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return (Imaging) ImagingError_ModeError();
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if (band < 0 || band >= imOut->bands)
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return (Imaging) ImagingError_ValueError("band index out of range");
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/* Special case for LXXA etc */
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if (imOut->bands == 2 && band == 1)
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band = 3;
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color = CLIP(color);
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/* Insert color into image */
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for (y = 0; y < imOut->ysize; y++) {
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UINT8* out = (UINT8*) imOut->image[y] + band;
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for (x = 0; x < imOut->xsize; x++) {
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*out = (UINT8) color;
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out += 4;
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}
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}
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return imOut;
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}
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