add part of opencv

Lib/opencv/sources/modules/imgcodecs/test/test_png.cpp

@@ -0,0 +1,98 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html
+#include "test_precomp.hpp"
+
+namespace opencv_test { namespace {
+
+#ifdef HAVE_PNG
+
+TEST(Imgcodecs_Png, write_big)
+{
+    const string root = cvtest::TS::ptr()->get_data_path();
+    const string filename = root + "readwrite/read.png";
+    const string dst_file = cv::tempfile(".png");
+    Mat img;
+    ASSERT_NO_THROW(img = imread(filename));
+    ASSERT_FALSE(img.empty());
+    EXPECT_EQ(13043, img.cols);
+    EXPECT_EQ(13917, img.rows);
+    ASSERT_NO_THROW(imwrite(dst_file, img));
+    EXPECT_EQ(0, remove(dst_file.c_str()));
+}
+
+TEST(Imgcodecs_Png, encode)
+{
+    vector<uchar> buff;
+    Mat img_gt = Mat::zeros(1000, 1000, CV_8U);
+    vector<int> param;
+    param.push_back(IMWRITE_PNG_COMPRESSION);
+    param.push_back(3); //default(3) 0-9.
+    EXPECT_NO_THROW(imencode(".png", img_gt, buff, param));
+    Mat img;
+    EXPECT_NO_THROW(img = imdecode(buff, IMREAD_ANYDEPTH)); // hang
+    EXPECT_FALSE(img.empty());
+    EXPECT_PRED_FORMAT2(cvtest::MatComparator(0, 0), img, img_gt);
+}
+
+TEST(Imgcodecs_Png, regression_ImreadVSCvtColor)
+{
+    const string root = cvtest::TS::ptr()->get_data_path();
+    const string imgName = root + "../cv/shared/lena.png";
+    Mat original_image = imread(imgName);
+    Mat gray_by_codec = imread(imgName, IMREAD_GRAYSCALE);
+    Mat gray_by_cvt;
+    cvtColor(original_image, gray_by_cvt, COLOR_BGR2GRAY);
+
+    Mat diff;
+    absdiff(gray_by_codec, gray_by_cvt, diff);
+    EXPECT_LT(cvtest::mean(diff)[0], 1.);
+    EXPECT_PRED_FORMAT2(cvtest::MatComparator(10, 0), gray_by_codec, gray_by_cvt);
+}
+
+// Test OpenCV issue 3075 is solved
+TEST(Imgcodecs_Png, read_color_palette_with_alpha)
+{
+    const string root = cvtest::TS::ptr()->get_data_path();
+    Mat img;
+
+    // First Test : Read PNG with alpha, imread flag -1
+    img = imread(root + "readwrite/color_palette_alpha.png", IMREAD_UNCHANGED);
+    ASSERT_FALSE(img.empty());
+    ASSERT_TRUE(img.channels() == 4);
+
+    // pixel is red in BGRA
+    EXPECT_EQ(img.at<Vec4b>(0, 0), Vec4b(0, 0, 255, 255));
+    EXPECT_EQ(img.at<Vec4b>(0, 1), Vec4b(0, 0, 255, 255));
+
+    // Second Test : Read PNG without alpha, imread flag -1
+    img = imread(root + "readwrite/color_palette_no_alpha.png", IMREAD_UNCHANGED);
+    ASSERT_FALSE(img.empty());
+    ASSERT_TRUE(img.channels() == 3);
+
+    // pixel is red in BGR
+    EXPECT_EQ(img.at<Vec3b>(0, 0), Vec3b(0, 0, 255));
+    EXPECT_EQ(img.at<Vec3b>(0, 1), Vec3b(0, 0, 255));
+
+    // Third Test : Read PNG with alpha, imread flag 1
+    img = imread(root + "readwrite/color_palette_alpha.png", IMREAD_COLOR);
+    ASSERT_FALSE(img.empty());
+    ASSERT_TRUE(img.channels() == 3);
+
+    // pixel is red in BGR
+    EXPECT_EQ(img.at<Vec3b>(0, 0), Vec3b(0, 0, 255));
+    EXPECT_EQ(img.at<Vec3b>(0, 1), Vec3b(0, 0, 255));
+
+    // Fourth Test : Read PNG without alpha, imread flag 1
+    img = imread(root + "readwrite/color_palette_no_alpha.png", IMREAD_COLOR);
+    ASSERT_FALSE(img.empty());
+    ASSERT_TRUE(img.channels() == 3);
+
+    // pixel is red in BGR
+    EXPECT_EQ(img.at<Vec3b>(0, 0), Vec3b(0, 0, 255));
+    EXPECT_EQ(img.at<Vec3b>(0, 1), Vec3b(0, 0, 255));
+}
+
+#endif // HAVE_PNG
+
+}} // namespace