Compression Group4 and Fax has no effect for tiff.

Prerequisites

• I have written a descriptive issue title
• I have verified that I am using the latest version of Magick.NET
• I have searched open and closed issues to ensure it has not already been reported

Description

Using ImageMagick, it is easy to create Group4/Fax compressed tiff: % magick logo: -compress Group4 tmp.tif % magick logo: -compress Fax tmp.tif But the following Magick.NET program (in Steps to Reproduce) does not compress the file: It prints: LZW Zip RLE NoCompression NoCompression NoCompression

Steps to Reproduce

using System;
using System.IO;
using ImageMagick;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string outFile = "./tmp.tif";
            foreach (var c in new CompressionMethod[]
            {
                CompressionMethod.LZW,
                CompressionMethod.Zip,
                CompressionMethod.RLE,
                CompressionMethod.Group4,
                CompressionMethod.Fax,
                CompressionMethod.NoCompression
            }) {
                MagickReadSettings settings = new MagickReadSettings();
                using (var image = new MagickImage("logo:", settings))
                {
                    image.Format = MagickFormat.Tiff;
                    image.Settings.Compression = c;
                    image.Write(outFile);
                }
                using (var image = new MagickImage(outFile))
                {
                    Console.WriteLine(image.Compression);
                }
                File.Delete(outFile);
            }
        }
    }
}

System Configuration

• Magick.NET version: 7.7.0 Q16 AnyCPU
• Environment (Operating system, version and so on): Windows 7 64bit
• Additional information:

[dlemstra]

@Jmuccigr Yes it will. And that will probably be released this weekend.

[t246246]

Thank you. I understand auto-grayscale false and Fax/Group4 have some kind of contradiction, but I had thought both -define and -set are valid setting: https://www.imagemagick.org/discourse-server/viewtopic.php?t=28453#p126332 , but guessing from current document, https://www.imagemagick.org/script/command-line-options.php#define , using -define for this purpose for tiff is not proper.