public void testPNGCompression()
{
// itterate over all test images
string[] files = new string[] { "files/ev.png", "files/test01.png", "files/test02.png" };
for (int i = 0; i < files.Length; i++)
{
// make sure compression works, file should be smaller
byte[] uncompressed = File.ReadAllBytes(files[i]);
int before = uncompressed.Length;
byte[] compressed = ZopfliPNG.compress(uncompressed);
int after = compressed.Length;
before.Should().BeGreaterOrEqualTo(after);
}
}
public void testPNGCompressionbyFilePath()
{
// copy a test file
string tempFile = Path.GetTempPath() + Guid.NewGuid().ToString("N") + ".png";
File.Copy("files/ev.png", tempFile);
// capture initial file size
FileInfo fi = new FileInfo(tempFile);
long before = fi.Length;
// compress image
ZopfliPNG.compress(tempFile);
// capture compressed file size
FileInfo fi2 = new FileInfo(tempFile);
long after = fi2.Length;
// remove file
File.Delete(tempFile);
// verify
before.Should().BeGreaterOrEqualTo(after);
}
public void testPNGCorrupt()
{
Action action = () => { byte[] compressed = ZopfliPNG.compress(File.ReadAllBytes("files/corrupt.png")); };
action.ShouldThrow <ZopfliPNGException>().WithMessage("incorrect PNG signature, it's no PNG or corrupted");
}
public void testPNGSmallHeader()
{
Action action = () => { byte[] compressed = ZopfliPNG.compress(File.ReadAllBytes("files/small-header.png")); };
action.ShouldThrow <ZopfliPNGException>().WithMessage("PNG file is smaller than a PNG header");
}
public void testPNGEmpty()
{
Action action = () => { byte[] compressed = ZopfliPNG.compress(File.ReadAllBytes("files/empty.png")); };
action.ShouldThrow <ZopfliPNGException>().WithMessage("empty input or file doesn't exist");
}