Gamma or brightness appears wrong after encoding.

[HSGorman]

Using the following code to convert a jpg to a jp2. When I read the jp2 the image appears too light (brightness or gamma appear to be off). Any ideas?

BitmapImageCreator.Register();
using (var bitmap = (Bitmap)Image.FromFile(@"C:\temp\jp2\llb.jpg"))
{
var enc = J2kImage.ToBytes(bitmap);
File.WriteAllBytes(@"C:\temp\jp2\llb.jp2", enc);
}

[anders9ustafsson]

@HSGorman Many thanks for reporting! Could you please include a sample image with this problem?

[anders9ustafsson]

@HSGorman Could be related to the failure to properly display the logo (file14) in codectest. But it would be good to have the sample as well.

[tomerinb]

same here.
got a very bright an contrasted image after converting to jp2.
is there a fix?
i attached the sample (original file and converted one)

here is the code i used:
System.Drawing.Image image = System.Drawing.Bitmap.FromFile("c:\img.jpg");
byte[] j2kArray = CSJ2K.J2kImage.ToBytes(image);
File.WriteAllBytes("c:\newImage.jp2", j2kArray);

Images.zip

[MikeRosoft]

Happened to me as well. Code:

        public static byte[] Encode(byte[] image, decimal? quality)
        {
            using var bytes = new MemoryStream(image);
            using var bitmap = new Bitmap(bytes);

            var parameters = J2kImage.GetDefaultEncoderParameterList(null);
            if (!quality.HasValue)
                parameters["lossless"] = "on";
            else
                parameters["rate"] = quality.ToString();

            return J2kImage.ToBytes(bitmap, parameters);
        }

Original image is PNG, resulting image is way too bright (as shown by IrfanView with the most recent plugins). Tested with package version 3.0, on Windows 10.

[MikeRosoft]

Follow-up: I wasn't able to upload the file, so here is a share link: https://app.box.com/s/t7pi1u8klidvwgzvixgnfwdj163ciosx (file name: testImages.zip).