/* imagediff - Compare two images * * Copyright © 2004 Richard D. Worth * Copyright © 2006 Red Hat, Inc. * * Permission to use, copy, modify, distribute, and sell this software * and its documentation for any purpose is hereby granted without * fee, provided that the above copyright notice appear in all copies * and that both that copyright notice and this permission notice * appear in supporting documentation, and that the name of the authors * not be used in advertising or publicity pertaining to distribution * of the software without specific, written prior permission. * The authors make no representations about the suitability of this * software for any purpose. It is provided "as is" without express * or implied warranty. * * THE AUTHORS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * Authors: Richard D. Worth <richard@theworths.org> * Carl Worth <cworth@cworth.org> */ #ifndef BUFFER_DIFF_H #define BUFFER_DIFF_H #include "cairo-test.h" typedef struct _buffer_diff_result { unsigned int pixels_changed; unsigned int max_diff; } buffer_diff_result_t; /* Compares two image buffers ignoring the alpha channel. * * Provides number of pixels changed and maximum single-channel * difference in result. * * Also fills in a "diff" buffer intended to visually show where the * images differ. */ void buffer_diff_noalpha (const unsigned char *buf_a, const unsigned char *buf_b, unsigned char *buf_diff, int width, int height, int stride, buffer_diff_result_t *result); /* The central algorithm to compare two images, and return the differences * in the surface_diff. * * Provides number of pixels changed and maximum single-channel * difference in result. */ cairo_status_t image_diff (const cairo_test_context_t *ctx, cairo_surface_t *surface_a, cairo_surface_t *surface_b, cairo_surface_t *surface_diff, buffer_diff_result_t *result); cairo_bool_t image_diff_is_failure (const buffer_diff_result_t *result, unsigned int tolerance); #endif