1 | /* |
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2 | * libpipi Proper image processing implementation library |
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3 | * Copyright (c) 2004-2008 Sam Hocevar <sam@zoy.org> |
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4 | * All Rights Reserved |
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5 | * |
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6 | * $Id$ |
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7 | * |
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8 | * This library is free software. It comes without any warranty, to |
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9 | * the extent permitted by applicable law. You can redistribute it |
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10 | * and/or modify it under the terms of the Do What The Fuck You Want |
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11 | * To Public License, Version 2, as published by Sam Hocevar. See |
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12 | * http://sam.zoy.org/wtfpl/COPYING for more details. |
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13 | */ |
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14 | |
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15 | /* |
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16 | * mean.c: Mean computation function |
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17 | */ |
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18 | |
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19 | #include "config.h" |
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20 | #include "common.h" |
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21 | |
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22 | #include "pipi.h" |
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23 | #include "pipi_internals.h" |
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24 | |
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25 | pipi_image_t *pipi_mean(pipi_image_t *img1, pipi_image_t *img2) |
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26 | { |
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27 | pipi_image_t *dst; |
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28 | pipi_pixels_t *img1p, *img2p, *dstp; |
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29 | float *img1data, *img2data, *dstdata; |
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30 | int x, y, w, h; |
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31 | |
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32 | if(img1->w != img2->w || img1->h != img2->h) |
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33 | return NULL; |
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34 | |
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35 | w = img1->w; |
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36 | h = img1->h; |
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37 | |
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38 | dst = pipi_new(w, h); |
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39 | dstp = pipi_getpixels(dst, PIPI_PIXELS_RGBA_F); |
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40 | dstdata = (float *)dstp->pixels; |
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41 | |
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42 | img1p = pipi_getpixels(img1, PIPI_PIXELS_RGBA_F); |
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43 | img1data = (float *)img1p->pixels; |
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44 | img2p = pipi_getpixels(img2, PIPI_PIXELS_RGBA_F); |
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45 | img2data = (float *)img2p->pixels; |
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46 | |
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47 | for(y = 0; y < h; y++) |
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48 | { |
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49 | for(x = 0; x < w; x++) |
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50 | { |
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51 | float p, q; |
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52 | |
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53 | p = img1data[4 * (y * w + x)]; |
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54 | q = img2data[4 * (y * w + x)]; |
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55 | dstdata[4 * (y * w + x)] = (p + q) * 0.5; |
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56 | |
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57 | p = img1data[4 * (y * w + x) + 1]; |
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58 | q = img2data[4 * (y * w + x) + 1]; |
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59 | dstdata[4 * (y * w + x) + 1] = (p + q) * 0.5; |
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60 | |
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61 | p = img1data[4 * (y * w + x) + 2]; |
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62 | q = img2data[4 * (y * w + x) + 2]; |
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63 | dstdata[4 * (y * w + x) + 2] = (p + q) * 0.5; |
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64 | |
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65 | p = img1data[4 * (y * w + x) + 3]; |
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66 | q = img2data[4 * (y * w + x) + 3]; |
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67 | dstdata[4 * (y * w + x) + 3] = (p + q) * 0.5; |
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68 | } |
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69 | } |
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70 | |
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71 | return dst; |
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72 | } |
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73 | |
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