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authorLei Zhang <thestig@chromium.org>2017-06-22 12:20:58 -0700
committerChromium commit bot <commit-bot@chromium.org>2017-06-22 19:38:17 +0000
commit143959dba65c78f404a5d8984edb5ec5e507325e (patch)
treed530dd8485ea3f457952eefe5bc8b6958b1cf8c9 /samples/image_diff.cc
parentb32a949d667600cb33e80e1bb8c97a23d96f27d9 (diff)
downloadpdfium-143959dba65c78f404a5d8984edb5ec5e507325e.tar.xz
Move image_diff code into testing/image_diff/
It is not actually a sample program to demonstrate how to use PDFium APIs. It is more of a test utility program. Remove header include dependency from samples/ to core/, to set a good example. Change-Id: Idd5d567c82314bcf0e4a7bec8a3210e7d57226ee Reviewed-on: https://pdfium-review.googlesource.com/6871 Reviewed-by: dsinclair <dsinclair@chromium.org> Commit-Queue: Lei Zhang <thestig@chromium.org>
Diffstat (limited to 'samples/image_diff.cc')
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diff --git a/samples/image_diff.cc b/samples/image_diff.cc
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--- a/samples/image_diff.cc
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@@ -1,352 +0,0 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This file input format is based loosely on
-// Tools/DumpRenderTree/ImageDiff.m
-
-// The exact format of this tool's output to stdout is important, to match
-// what the run-webkit-tests script expects.
-
-#include <assert.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-
-#include <algorithm>
-#include <iostream>
-#include <map>
-#include <string>
-#include <vector>
-
-#include "core/fxcrt/fx_memory.h"
-#include "samples/image_diff_png.h"
-#include "third_party/base/logging.h"
-#include "third_party/base/numerics/safe_conversions.h"
-
-#if defined(OS_WIN)
-#include <windows.h>
-#endif
-
-// Return codes used by this utility.
-static const int kStatusSame = 0;
-static const int kStatusDifferent = 1;
-static const int kStatusError = 2;
-
-// Color codes.
-static const uint32_t RGBA_RED = 0x000000ff;
-static const uint32_t RGBA_ALPHA = 0xff000000;
-
-class Image {
- public:
- Image() : w_(0), h_(0) {
- }
-
- Image(const Image& image)
- : w_(image.w_),
- h_(image.h_),
- data_(image.data_) {
- }
-
- bool has_image() const {
- return w_ > 0 && h_ > 0;
- }
-
- int w() const {
- return w_;
- }
-
- int h() const {
- return h_;
- }
-
- const unsigned char* data() const {
- return &data_.front();
- }
-
- // Creates the image from the given filename on disk, and returns true on
- // success.
- bool CreateFromFilename(const std::string& path) {
- FILE* f = fopen(path.c_str(), "rb");
- if (!f)
- return false;
-
- std::vector<unsigned char> compressed;
- const size_t kBufSize = 1024;
- unsigned char buf[kBufSize];
- size_t num_read = 0;
- while ((num_read = fread(buf, 1, kBufSize, f)) > 0) {
- compressed.insert(compressed.end(), buf, buf + num_read);
- }
-
- fclose(f);
-
- if (!image_diff_png::DecodePNG(compressed.data(), compressed.size(), &data_,
- &w_, &h_)) {
- Clear();
- return false;
- }
- return true;
- }
-
- void Clear() {
- w_ = h_ = 0;
- data_.clear();
- }
-
- // Returns the RGBA value of the pixel at the given location
- uint32_t pixel_at(int x, int y) const {
- if (!pixel_in_bounds(x, y))
- return 0;
- return *reinterpret_cast<const uint32_t*>(&(data_[pixel_address(x, y)]));
- }
-
- void set_pixel_at(int x, int y, uint32_t color) {
- if (!pixel_in_bounds(x, y))
- return;
-
- void* addr = &data_[pixel_address(x, y)];
- *reinterpret_cast<uint32_t*>(addr) = color;
- }
-
- private:
- bool pixel_in_bounds(int x, int y) const {
- return x >= 0 && x < w_ && y >= 0 && y < h_;
- }
-
- size_t pixel_address(int x, int y) const { return (y * w_ + x) * 4; }
-
- // Pixel dimensions of the image.
- int w_;
- int h_;
-
- std::vector<unsigned char> data_;
-};
-
-float CalculateDifferencePercentage(const Image& actual, int pixels_different) {
- // Like the WebKit ImageDiff tool, we define percentage different in terms
- // of the size of the 'actual' bitmap.
- float total_pixels =
- static_cast<float>(actual.w()) * static_cast<float>(actual.h());
- if (total_pixels == 0) {
- // When the bitmap is empty, they are 100% different.
- return 100.0f;
- }
- return 100.0f * pixels_different / total_pixels;
-}
-
-void CountImageSizeMismatchAsPixelDifference(const Image& baseline,
- const Image& actual,
- int* pixels_different) {
- int w = std::min(baseline.w(), actual.w());
- int h = std::min(baseline.h(), actual.h());
-
- // Count pixels that are a difference in size as also being different.
- int max_w = std::max(baseline.w(), actual.w());
- int max_h = std::max(baseline.h(), actual.h());
- // These pixels are off the right side, not including the lower right corner.
- *pixels_different += (max_w - w) * h;
- // These pixels are along the bottom, including the lower right corner.
- *pixels_different += (max_h - h) * max_w;
-}
-
-float PercentageDifferent(const Image& baseline, const Image& actual) {
- int w = std::min(baseline.w(), actual.w());
- int h = std::min(baseline.h(), actual.h());
-
- // Compute pixels different in the overlap.
- int pixels_different = 0;
- for (int y = 0; y < h; ++y) {
- for (int x = 0; x < w; ++x) {
- if (baseline.pixel_at(x, y) != actual.pixel_at(x, y))
- ++pixels_different;
- }
- }
-
- CountImageSizeMismatchAsPixelDifference(baseline, actual, &pixels_different);
- return CalculateDifferencePercentage(actual, pixels_different);
-}
-
-float HistogramPercentageDifferent(const Image& baseline, const Image& actual) {
- // TODO(johnme): Consider using a joint histogram instead, as described in
- // "Comparing Images Using Joint Histograms" by Pass & Zabih
- // http://www.cs.cornell.edu/~rdz/papers/pz-jms99.pdf
-
- int w = std::min(baseline.w(), actual.w());
- int h = std::min(baseline.h(), actual.h());
-
- // Count occurences of each RGBA pixel value of baseline in the overlap.
- std::map<uint32_t, int32_t> baseline_histogram;
- for (int y = 0; y < h; ++y) {
- for (int x = 0; x < w; ++x) {
- // hash_map operator[] inserts a 0 (default constructor) if key not found.
- ++baseline_histogram[baseline.pixel_at(x, y)];
- }
- }
-
- // Compute pixels different in the histogram of the overlap.
- int pixels_different = 0;
- for (int y = 0; y < h; ++y) {
- for (int x = 0; x < w; ++x) {
- uint32_t actual_rgba = actual.pixel_at(x, y);
- auto it = baseline_histogram.find(actual_rgba);
- if (it != baseline_histogram.end() && it->second > 0)
- --it->second;
- else
- ++pixels_different;
- }
- }
-
- CountImageSizeMismatchAsPixelDifference(baseline, actual, &pixels_different);
- return CalculateDifferencePercentage(actual, pixels_different);
-}
-
-void PrintHelp() {
- fprintf(stderr,
- "Usage:\n"
- " image_diff [--histogram] <compare file> <reference file>\n"
- " Compares two files on disk, returning 0 when they are the same;\n"
- " passing \"--histogram\" additionally calculates a diff of the\n"
- " RGBA value histograms (which is resistant to shifts in layout)\n"
- " image_diff --diff <compare file> <reference file> <output file>\n"
- " Compares two files on disk, outputs an image that visualizes the\n"
- " difference to <output file>\n");
-}
-
-int CompareImages(const std::string& file1,
- const std::string& file2,
- bool compare_histograms) {
- Image actual_image;
- Image baseline_image;
-
- if (!actual_image.CreateFromFilename(file1)) {
- fprintf(stderr, "image_diff: Unable to open file \"%s\"\n", file1.c_str());
- return kStatusError;
- }
- if (!baseline_image.CreateFromFilename(file2)) {
- fprintf(stderr, "image_diff: Unable to open file \"%s\"\n", file2.c_str());
- return kStatusError;
- }
-
- if (compare_histograms) {
- float percent = HistogramPercentageDifferent(actual_image, baseline_image);
- const char* passed = percent > 0.0 ? "failed" : "passed";
- printf("histogram diff: %01.2f%% %s\n", percent, passed);
- }
-
- const char* const diff_name = compare_histograms ? "exact diff" : "diff";
- float percent = PercentageDifferent(actual_image, baseline_image);
- const char* const passed = percent > 0.0 ? "failed" : "passed";
- printf("%s: %01.2f%% %s\n", diff_name, percent, passed);
-
- if (percent > 0.0) {
- // failure: The WebKit version also writes the difference image to
- // stdout, which seems excessive for our needs.
- return kStatusDifferent;
- }
- // success
- return kStatusSame;
-}
-
-bool CreateImageDiff(const Image& image1, const Image& image2, Image* out) {
- int w = std::min(image1.w(), image2.w());
- int h = std::min(image1.h(), image2.h());
- *out = Image(image1);
- bool same = (image1.w() == image2.w()) && (image1.h() == image2.h());
-
- // TODO(estade): do something with the extra pixels if the image sizes
- // are different.
- for (int y = 0; y < h; ++y) {
- for (int x = 0; x < w; ++x) {
- uint32_t base_pixel = image1.pixel_at(x, y);
- if (base_pixel != image2.pixel_at(x, y)) {
- // Set differing pixels red.
- out->set_pixel_at(x, y, RGBA_RED | RGBA_ALPHA);
- same = false;
- } else {
- // Set same pixels as faded.
- uint32_t alpha = base_pixel & RGBA_ALPHA;
- uint32_t new_pixel = base_pixel - ((alpha / 2) & RGBA_ALPHA);
- out->set_pixel_at(x, y, new_pixel);
- }
- }
- }
-
- return same;
-}
-
-int DiffImages(const std::string& file1,
- const std::string& file2,
- const std::string& out_file) {
- Image actual_image;
- Image baseline_image;
-
- if (!actual_image.CreateFromFilename(file1)) {
- fprintf(stderr, "image_diff: Unable to open file \"%s\"\n", file1.c_str());
- return kStatusError;
- }
- if (!baseline_image.CreateFromFilename(file2)) {
- fprintf(stderr, "image_diff: Unable to open file \"%s\"\n", file2.c_str());
- return kStatusError;
- }
-
- Image diff_image;
- bool same = CreateImageDiff(baseline_image, actual_image, &diff_image);
- if (same)
- return kStatusSame;
-
- std::vector<unsigned char> png_encoding;
- image_diff_png::EncodeRGBAPNG(
- diff_image.data(), diff_image.w(), diff_image.h(),
- diff_image.w() * 4, &png_encoding);
-
- FILE* f = fopen(out_file.c_str(), "wb");
- if (!f)
- return kStatusError;
-
- size_t size = png_encoding.size();
- char* ptr = reinterpret_cast<char*>(&png_encoding.front());
- if (fwrite(ptr, 1, size, f) != size)
- return kStatusError;
-
- return kStatusDifferent;
-}
-
-int main(int argc, const char* argv[]) {
- FXMEM_InitializePartitionAlloc();
-
- bool histograms = false;
- bool produce_diff_image = false;
- std::string filename1;
- std::string filename2;
- std::string diff_filename;
-
- int i;
- for (i = 1; i < argc; ++i) {
- const char* arg = argv[i];
- if (strstr(arg, "--") != arg)
- break;
- if (strcmp(arg, "--histogram") == 0) {
- histograms = true;
- } else if (strcmp(arg, "--diff") == 0) {
- produce_diff_image = true;
- }
- }
- if (i < argc)
- filename1 = argv[i++];
- if (i < argc)
- filename2 = argv[i++];
- if (i < argc)
- diff_filename = argv[i++];
-
- if (produce_diff_image) {
- if (!diff_filename.empty()) {
- return DiffImages(filename1, filename2, diff_filename);
- }
- } else if (!filename2.empty()) {
- return CompareImages(filename1, filename2, histograms);
- }
-
- PrintHelp();
- return kStatusError;
-}