X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=inline;f=images%2Fimage-sig.c;h=cd07b8a3ab0fd603eeb5719da4a5b837aa7d75b9;hb=b7ae681630e44b0a6d28ed441c2514dac80004e6;hp=fab1de3970056c20490da634c5cc270678cc7940;hpb=19b12adae1eafc2b9fde886157ab3a35d80705dc;p=libucw.git diff --git a/images/image-sig.c b/images/image-sig.c index fab1de39..cd07b8a3 100644 --- a/images/image-sig.c +++ b/images/image-sig.c @@ -1,4 +1,4 @@ -#define LOCAL_DEBUG +#undef LOCAL_DEBUG #include "sherlock/sherlock.h" #include "lib/math.h" @@ -6,56 +6,9 @@ #include "images/images.h" #include "images/image-obj.h" #include "images/image-sig.h" +#include "images/color.h" #include -#include - -/* - * Color spaces - * - * http://www.tecgraf.puc-rio.br/~mgattass/color/ColorIndex.html - * - */ - -#define REF_WHITE_X 0.96422 -#define REF_WHITE_Y 1. -#define REF_WHITE_Z 0.82521 - -/* sRGB to XYZ */ -static void -srgb_to_xyz_slow(double srgb[3], double xyz[3]) -{ - double a[3]; - for (uns i = 0; i < 3; i++) - if (srgb[i] > 0.04045) - a[i] = pow((srgb[i] + 0.055) * (1 / 1.055), 2.4); - else - a[i] = srgb[i] * (1 / 12.92); - xyz[0] = 0.412424 * a[0] + 0.357579 * a[1] + 0.180464 * a[2]; - xyz[1] = 0.212656 * a[0] + 0.715158 * a[1] + 0.072186 * a[2]; - xyz[2] = 0.019332 * a[0] + 0.119193 * a[1] + 0.950444 * a[2]; -} - -/* XYZ to CIE-Luv */ -static void -xyz_to_luv_slow(double xyz[3], double luv[3]) -{ - double sum = xyz[0] + 15 * xyz[1] + 3 * xyz[2]; - if (sum < 0.000001) - luv[0] = luv[1] = luv[2] = 0; - else - { - double var_u = 4 * xyz[0] / sum; - double var_v = 9 * xyz[1] / sum; - if (xyz[1] > 0.008856) - luv[0] = 116 * pow(xyz[1], 1 / 3.) - 16; - else - luv[0] = (116 * 7.787) * xyz[1]; - luv[1] = luv[0] * (13 * (var_u - 4 * REF_WHITE_X / (REF_WHITE_X + 15 * REF_WHITE_Y + 3 * REF_WHITE_Z))); - luv[2] = luv[0] * (13 * (var_v - 9 * REF_WHITE_Y / (REF_WHITE_X + 15 * REF_WHITE_Y + 3 * REF_WHITE_Z))); - /* intervals [0..100], [-134..220], [-140..122] */ - } -} struct block { uns l, u, v; /* average Luv coefficients */ @@ -63,7 +16,7 @@ struct block { }; int -compute_image_signature(struct image *image, struct image_signature *sig) +compute_image_signature(struct image_data *image, struct image_signature *sig) { uns width = image->width; uns height = image->height; @@ -97,20 +50,16 @@ compute_image_signature(struct image *image, struct image_signature *sig) for (uns y = 0; y < 4; y++, p += 3 * (width - 4)) for (uns x = 0; x < 4; x++, p += 3) { - double rgb[3], luv[3], xyz[3]; - rgb[0] = p[0] / 255.; - rgb[1] = p[1] / 255.; - rgb[2] = p[2] / 255.; - srgb_to_xyz_slow(rgb, xyz); - xyz_to_luv_slow(xyz, luv); + byte luv[3]; + srgb_to_luv_pixel(luv, p); l_sum += *tp++ = luv[0]; - u_sum += luv[1] + 150; - v_sum += luv[2] + 150; + u_sum += luv[1]; + v_sum += luv[2]; } - block->l = l_sum; - block->u = u_sum; - block->v = v_sum; + block->l = (l_sum >> 4); + block->u = (u_sum >> 4); + block->v = (v_sum >> 4); /* Apply Daubechies wavelet transformation * FIXME: @@ -149,9 +98,9 @@ compute_image_signature(struct image *image, struct image_signature *sig) } /* Extract energies in LH, HL and HH bands */ - block->lh = sqrt(t[8] * t[8] + t[9] * t[9] + t[12] * t[12] + t[13] * t[13]); - block->hl = sqrt(t[2] * t[2] + t[3] * t[3] + t[6] * t[6] + t[7] * t[7]); - block->hh = sqrt(t[10] * t[10] + t[11] * t[11] + t[14] * t[14] + t[15] * t[15]); + block->lh = CLAMP((int)(sqrt(t[8] * t[8] + t[9] * t[9] + t[12] * t[12] + t[13] * t[13]) / 16), 0, 255); + block->hl = CLAMP((int)(sqrt(t[2] * t[2] + t[3] * t[3] + t[6] * t[6] + t[7] * t[7]) / 16), 0, 255); + block->hh = CLAMP((int)(sqrt(t[10] * t[10] + t[11] * t[11] + t[14] * t[14] + t[15] * t[15]) / 16), 0, 255); } /* FIXME: simple average is for testing pusposes only */