/// <summary>
/// Returns hash of the image.
/// </summary>
/// <typeparam name="THash">Type of hash value.</typeparam>
/// <param name="hasher">Implementation of the <see cref="IImageHasher"/>.</param>
/// <param name="filePath">Path to an image to be hashed.</param>
/// <param name="computer">Implementation of the hash calculation algorithm.</param>
/// <exception cref="ArgumentNullException">
/// The <paramref name="hasher"/> parameter is null.
/// The <paramref name="computer"/> parameter is null.
/// </exception>
/// <exception cref="ArgumentException">
/// The <paramref name="filePath"/> parameter is null, empty, or consists only of white-space characters.
/// </exception>
/// <example>
/// <code>
/// var hasher = new ImageHasher(transformer);
///
/// var hash = hasher.Calculate("cat.jpg", KnownImageHashes.Difference64);
/// </code>
/// </example>
public static THash Calculate <THash>(this IImageHasher hasher, string filePath, IImageHashComputer <THash> computer)
where THash : struct, IImageHashComparable <THash>
{
if (hasher == null)
{
throw new ArgumentNullException(nameof(hasher));
}
if (computer == null)
{
throw new ArgumentNullException(nameof(computer));
}
if (string.IsNullOrWhiteSpace(filePath))
{
throw new ArgumentException("Value cannot be null or whitespace.", nameof(filePath));
}
using var stream = File.OpenRead(filePath);
return(hasher.Calculate(stream, computer));
}
public ImageDifferenceHash64 Perceptash_Magick_Difference_64()
{
return(_perceptashMagick.Calculate(_imageStream, KnownImageHashes.Difference64));
}
public ImageDifferenceHash64 Perceptash_ImageSharp_Difference_64()
{
return(_perceptashImageSharp.Calculate(_imageStream, KnownImageHashes.Difference64));
}