/* * libpipi Pathetic image processing interface library * Copyright (c) 2004-2008 Sam Hocevar * All Rights Reserved * * $Id$ * * This library is free software. It comes without any warranty, to * the extent permitted by applicable law. You can redistribute it * and/or modify it under the terms of the Do What The Fuck You Want * To Public License, Version 2, as published by Sam Hocevar. See * http://sam.zoy.org/wtfpl/COPYING for more details. */ /* * mulscreen.c: multiply and screen computation functions */ #include "config.h" #include "common.h" #include "pipi.h" #include "pipi_internals.h" pipi_image_t *pipi_multiply(pipi_image_t *img1, pipi_image_t *img2) { pipi_image_t *dst; pipi_pixels_t *img1p, *img2p, *dstp; float *img1data, *img2data, *dstdata; int x, y, w, h; if(img1->w != img2->w || img1->h != img2->h) return NULL; w = img1->w; h = img1->h; dst = pipi_new(w, h); dstp = pipi_getpixels(dst, PIPI_PIXELS_RGBA_F); dstdata = (float *)dstp->pixels; img1p = pipi_getpixels(img1, PIPI_PIXELS_RGBA_F); img1data = (float *)img1p->pixels; img2p = pipi_getpixels(img2, PIPI_PIXELS_RGBA_F); img2data = (float *)img2p->pixels; for(y = 0; y < h; y++) { for(x = 0; x < w; x++) { float p, q; p = img1data[4 * (y * w + x)]; q = img2data[4 * (y * w + x)]; dstdata[4 * (y * w + x)] = p * q; p = img1data[4 * (y * w + x) + 1]; q = img2data[4 * (y * w + x) + 1]; dstdata[4 * (y * w + x) + 1] = p * q; p = img1data[4 * (y * w + x) + 2]; q = img2data[4 * (y * w + x) + 2]; dstdata[4 * (y * w + x) + 2] = p * q; p = img1data[4 * (y * w + x) + 3]; q = img2data[4 * (y * w + x) + 3]; dstdata[4 * (y * w + x) + 3] = p * q; } } return dst; } pipi_image_t *pipi_divide(pipi_image_t *img1, pipi_image_t *img2) { pipi_image_t *dst; pipi_pixels_t *img1p, *img2p, *dstp; float *img1data, *img2data, *dstdata; int x, y, w, h; if(img1->w != img2->w || img1->h != img2->h) return NULL; w = img1->w; h = img1->h; dst = pipi_new(w, h); dstp = pipi_getpixels(dst, PIPI_PIXELS_RGBA_F); dstdata = (float *)dstp->pixels; img1p = pipi_getpixels(img1, PIPI_PIXELS_RGBA_F); img1data = (float *)img1p->pixels; img2p = pipi_getpixels(img2, PIPI_PIXELS_RGBA_F); img2data = (float *)img2p->pixels; for(y = 0; y < h; y++) { for(x = 0; x < w; x++) { float p, q; p = img1data[4 * (y * w + x)]; q = img2data[4 * (y * w + x)]; dstdata[4 * (y * w + x)] = p >= q ? 1. : p / q; p = img1data[4 * (y * w + x) + 1]; q = img2data[4 * (y * w + x) + 1]; dstdata[4 * (y * w + x) + 1] = p >= q ? 1. : p / q; p = img1data[4 * (y * w + x) + 2]; q = img2data[4 * (y * w + x) + 2]; dstdata[4 * (y * w + x) + 2] = p >= q ? 1. : p / q; p = img1data[4 * (y * w + x) + 3]; q = img2data[4 * (y * w + x) + 3]; dstdata[4 * (y * w + x) + 3] = p >= q ? 1. : p / q; } } return dst; } pipi_image_t *pipi_screen(pipi_image_t *img1, pipi_image_t *img2) { pipi_image_t *dst; pipi_pixels_t *img1p, *img2p, *dstp; float *img1data, *img2data, *dstdata; int x, y, w, h; if(img1->w != img2->w || img1->h != img2->h) return NULL; w = img1->w; h = img1->h; dst = pipi_new(w, h); dstp = pipi_getpixels(dst, PIPI_PIXELS_RGBA_F); dstdata = (float *)dstp->pixels; img1p = pipi_getpixels(img1, PIPI_PIXELS_RGBA_F); img1data = (float *)img1p->pixels; img2p = pipi_getpixels(img2, PIPI_PIXELS_RGBA_F); img2data = (float *)img2p->pixels; for(y = 0; y < h; y++) { for(x = 0; x < w; x++) { float p, q; p = img1data[4 * (y * w + x)]; q = img2data[4 * (y * w + x)]; dstdata[4 * (y * w + x)] = p + q - p * q; p = img1data[4 * (y * w + x) + 1]; q = img2data[4 * (y * w + x) + 1]; dstdata[4 * (y * w + x) + 1] = p + q - p * q; p = img1data[4 * (y * w + x) + 2]; q = img2data[4 * (y * w + x) + 2]; dstdata[4 * (y * w + x) + 2] = p + q - p * q; p = img1data[4 * (y * w + x) + 3]; q = img2data[4 * (y * w + x) + 3]; dstdata[4 * (y * w + x) + 3] = p + q - p * q; } } return dst; } pipi_image_t *pipi_overlay(pipi_image_t *img1, pipi_image_t *img2) { pipi_image_t *dst; pipi_pixels_t *img1p, *img2p, *dstp; float *img1data, *img2data, *dstdata; int x, y, w, h; if(img1->w != img2->w || img1->h != img2->h) return NULL; w = img1->w; h = img1->h; dst = pipi_new(w, h); dstp = pipi_getpixels(dst, PIPI_PIXELS_RGBA_F); dstdata = (float *)dstp->pixels; img1p = pipi_getpixels(img1, PIPI_PIXELS_RGBA_F); img1data = (float *)img1p->pixels; img2p = pipi_getpixels(img2, PIPI_PIXELS_RGBA_F); img2data = (float *)img2p->pixels; for(y = 0; y < h; y++) { for(x = 0; x < w; x++) { float p, q; p = img1data[4 * (y * w + x)]; q = img2data[4 * (y * w + x)]; dstdata[4 * (y * w + x)] = p * (p + 2. * q * (1. - p)); p = img1data[4 * (y * w + x) + 1]; q = img2data[4 * (y * w + x) + 1]; dstdata[4 * (y * w + x) + 1] = p * (p + 2. * q * (1. - p)); p = img1data[4 * (y * w + x) + 2]; q = img2data[4 * (y * w + x) + 2]; dstdata[4 * (y * w + x) + 2] = p * (p + 2. * q * (1. - p)); p = img1data[4 * (y * w + x) + 3]; q = img2data[4 * (y * w + x) + 3]; dstdata[4 * (y * w + x) + 3] = p * (p + 2. * q * (1. - p)); } } return dst; }