Strange Notepad++ HEX-editor plugin

Question

The goal is to write byte array to file. I have byte array fits[] with some bytes and then:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace _32_to_16
{
    class Program
    {
        static void Main(string[] args)
        {
            byte[] fits = File.ReadAllBytes("1.myf");
            byte[] img = new byte[fits.Length / 2];
            for (int i = 0; i < fits.Length; i += 4) //Drops 2 high bytes
            {
                img[i/2] = fits[i + 2];
                img[i/2 + 1] = fits[i + 3];
            }
            File.WriteAllBytes("new.myf", img);
        }
    }
}

Before writing to the file img[] has same values:

• img[0]=0x31
• img[1]=0x27
• img[2]=0x31
• img[3]=0xe2
• and so on...

After writing to file, in HEX editor i see

• 00000000: 31 27 31 3f and other wrong values.

Sometimes, with other fits[] values, img[] array write correctly to file. What I`m doing wrong?
File for test 1.myf (which makes wrong results) https://www.dropbox.com/s/6xyf761oqm8j7y1/1.myf?dl=0 File for test 2.myf (correct writes to file) https://www.dropbox.com/s/zrglpx7kmpydurz/2.myf?dl=0

I simplified the code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace _32_to_16
{
    class Program
    {
        static void Main(string[] args)
        {
            byte[] img_correct = new byte[8] { 0xbd, 0x19, 0xbd, 0x72, 0xbd, 0x93, 0xbd, 0xf7 };
            File.WriteAllBytes("img_correct.myf", img_correct);

            byte[] img_strange = new byte[8] { 0x33, 0x08, 0x33, 0xac, 0x33, 0xe3, 0x33, 0x94 };
            File.WriteAllBytes("img_strange.myf", img_strange);
        }
    }
}

in HEX-editor img_correct.myf looks like this: bd 19 bd 72 bd 93 bd f7

in HEX-editor img_strange.myf looks like this: 33 08 33 3f 3f 3f

Answer 1

You're using the HEX-Editor plugin from Notepad++, which seems to have a problem reading binary files.

Try with another hex editor and it should display the correct values.

Here's a screenshot of HxD and HEX-Editor displaying the same file