/*====================================================================* - Copyright (C) 2001 Leptonica. All rights reserved. - - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions - are met: - 1. Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - 2. Redistributions in binary form must reproduce the above - copyright notice, this list of conditions and the following - disclaimer in the documentation and/or other materials - provided with the distribution. - - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ANY - CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, - EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, - PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR - PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY - OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING - NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *====================================================================*/ /* * subpixel_reg.c * * Regression test for subpixel scaling. */ #ifdef HAVE_CONFIG_H #include #endif /* HAVE_CONFIG_H */ #include "allheaders.h" void AddTextAndSave(PIXA *pixa, PIX *pixs, L_BMF *bmf, const char *textstr, l_int32 location, l_uint32 val); const char *textstr[] = {"Downscaled with sharpening", "Subpixel scaling; horiz R-G-B", "Subpixel scaling; horiz B-G-R", "Subpixel scaling; vert R-G-B", "Subpixel scaling; vert B-G-R"}; int main(int argc, char **argv) { l_float32 scalefact; L_BMF *bmf, *bmftop; L_KERNEL *kel, *kelx, *kely; PIX *pixs, *pixg, *pixt, *pixd; PIX *pix1, *pix2, *pix3, *pix4, *pix5, *pix6, *pix7, *pix8; PIXA *pixa; L_REGPARAMS *rp; #if !defined(HAVE_LIBPNG) L_ERROR("This test requires libpng to run.\n", "subpixel_reg"); exit(77); #endif if (regTestSetup(argc, argv, &rp)) return 1; /* ----------------- Test on 8 bpp grayscale ---------------------*/ pixa = pixaCreate(5); bmf = bmfCreate("./fonts", 6); bmftop = bmfCreate("./fonts", 10); pixs = pixRead("lucasta.047.jpg"); pixg = pixScale(pixs, 0.4, 0.4); /* 8 bpp grayscale */ pix1 = pixConvertTo32(pixg); /* 32 bpp rgb */ AddTextAndSave(pixa, pix1, bmf, textstr[0], L_ADD_BELOW, 0xff000000); pix2 = pixConvertGrayToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_RGB); AddTextAndSave(pixa, pix2, bmf, textstr[1], L_ADD_BELOW, 0x00ff0000); pix3 = pixConvertGrayToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_BGR); AddTextAndSave(pixa, pix3, bmf, textstr[2], L_ADD_BELOW, 0x0000ff00); pix4 = pixConvertGrayToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_VRGB); AddTextAndSave(pixa, pix4, bmf, textstr[3], L_ADD_BELOW, 0x00ff0000); pix5 = pixConvertGrayToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_VBGR); AddTextAndSave(pixa, pix5, bmf, textstr[4], L_ADD_BELOW, 0x0000ff00); pixt = pixaDisplayTiledInColumns(pixa, 5, 1.0, 30, 2); pixd = pixAddSingleTextblock(pixt, bmftop, "Regression test for subpixel scaling: gray", 0xff00ff00, L_ADD_ABOVE, NULL); regTestWritePixAndCheck(rp, pixd, IFF_JFIF_JPEG); /* 0 */ pixDisplayWithTitle(pixd, 50, 50, NULL, rp->display); pixaDestroy(&pixa); pixDestroy(&pixs); pixDestroy(&pixg); pixDestroy(&pixt); pixDestroy(&pixd); pixDestroy(&pix1); pixDestroy(&pix2); pixDestroy(&pix3); pixDestroy(&pix4); pixDestroy(&pix5); /* ----------------- Test on 32 bpp rgb ---------------------*/ pixa = pixaCreate(5); pixs = pixRead("fish24.jpg"); pix1 = pixScale(pixs, 0.4, 0.4); AddTextAndSave(pixa, pix1, bmf, textstr[0], L_ADD_BELOW, 0xff000000); pix2 = pixConvertToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_RGB); AddTextAndSave(pixa, pix2, bmf, textstr[1], L_ADD_BELOW, 0x00ff0000); pix3 = pixConvertToSubpixelRGB(pixs, 0.4, 0.35, L_SUBPIXEL_ORDER_BGR); AddTextAndSave(pixa, pix3, bmf, textstr[2], L_ADD_BELOW, 0x0000ff00); pix4 = pixConvertToSubpixelRGB(pixs, 0.4, 0.45, L_SUBPIXEL_ORDER_VRGB); AddTextAndSave(pixa, pix4, bmf, textstr[3], L_ADD_BELOW, 0x00ff0000); pix5 = pixConvertToSubpixelRGB(pixs, 0.4, 0.4, L_SUBPIXEL_ORDER_VBGR); AddTextAndSave(pixa, pix5, bmf, textstr[4], L_ADD_BELOW, 0x0000ff00); pixt = pixaDisplayTiledInColumns(pixa, 5, 1.0, 30, 2); pixd = pixAddSingleTextblock(pixt, bmftop, "Regression test for subpixel scaling: color", 0xff00ff00, L_ADD_ABOVE, NULL); regTestWritePixAndCheck(rp, pixd, IFF_JFIF_JPEG); /* 1 */ pixDisplayWithTitle(pixd, 50, 350, NULL, rp->display); pixaDestroy(&pixa); pixDestroy(&pixs); pixDestroy(&pixt); pixDestroy(&pixd); pixDestroy(&pix1); pixDestroy(&pix2); pixDestroy(&pix3); pixDestroy(&pix4); pixDestroy(&pix5); bmfDestroy(&bmf); bmfDestroy(&bmftop); /* --------------- Test on images that are initially 1 bpp ------------*/ /* For these, it is better to apply a lowpass filter before scaling */ /* Normal scaling of 8 bpp grayscale */ scalefact = 800. / 2320.; pixs = pixRead("patent.png"); /* sharp, 300 ppi, 1 bpp image */ pix1 = pixConvertTo8(pixs, FALSE); /* use 8 bpp input */ pix2 = pixScale(pix1, scalefact, scalefact); regTestWritePixAndCheck(rp, pix2, IFF_PNG); /* 2 */ /* Subpixel scaling; bad because there is very little aliasing. */ pix3 = pixConvertToSubpixelRGB(pix1, scalefact, scalefact, L_SUBPIXEL_ORDER_RGB); regTestWritePixAndCheck(rp, pix3, IFF_PNG); /* 3 */ /* Get same (bad) result doing subpixel rendering on RGB input */ pix4 = pixConvertTo32(pixs); pix5 = pixConvertToSubpixelRGB(pix4, scalefact, scalefact, L_SUBPIXEL_ORDER_RGB); regTestComparePix(rp, pix3, pix5); /* 4 */ regTestWritePixAndCheck(rp, pix5, IFF_PNG); /* 5 */ /* Now apply a small lowpass filter before scaling. */ makeGaussianKernelSep(2, 2, 1.0, 1.0, &kelx, &kely); startTimer(); pix6 = pixConvolveSep(pix1, kelx, kely, 8, 1); /* normalized */ lept_stderr("Time sep: %7.3f\n", stopTimer()); regTestWritePixAndCheck(rp, pix6, IFF_PNG); /* 6 */ /* Get same lowpass result with non-separated convolution */ kel = makeGaussianKernel(2, 2, 1.0, 1.0); startTimer(); pix7 = pixConvolve(pix1, kel, 8, 1); /* normalized */ lept_stderr("Time non-sep: %7.3f\n", stopTimer()); regTestComparePix(rp, pix6, pix7); /* 7 */ /* Now do the subpixel scaling on this slightly blurred image */ pix8 = pixConvertToSubpixelRGB(pix6, scalefact, scalefact, L_SUBPIXEL_ORDER_RGB); regTestWritePixAndCheck(rp, pix8, IFF_PNG); /* 8 */ kernelDestroy(&kelx); kernelDestroy(&kely); kernelDestroy(&kel); pixDestroy(&pixs); pixDestroy(&pix1); pixDestroy(&pix2); pixDestroy(&pix3); pixDestroy(&pix4); pixDestroy(&pix5); pixDestroy(&pix6); pixDestroy(&pix7); pixDestroy(&pix8); return regTestCleanup(rp); } void AddTextAndSave(PIXA *pixa, PIX *pixs, L_BMF *bmf, const char *textstr, l_int32 location, l_uint32 val) { l_int32 n, ovf; PIX *pixt; pixt = pixAddSingleTextblock(pixs, bmf, textstr, val, location, &ovf); n = pixaGetCount(pixa); pixaAddPix(pixa, pixt, L_INSERT); if (ovf) lept_stderr("Overflow writing text in image %d\n", n + 1); return; }