Pasted

public static class ImageExtensions
{
    /* 
     *  This is free and unencumbered software released into the public domain.
     *  
     *  Anyone is free to copy, modify, publish, use, compile, sell, or
     *  distribute this software, either in source code form or as a compiled
     *  binary, for any purpose, commercial or non-commercial, and by any
     *  means.
     *  
     *  In jurisdictions that recognize copyright laws, the author or authors
     *  of this software dedicate any and all copyright interest in the
     *  software to the public domain. We make this dedication for the benefit
     *  of the public at large and to the detriment of our heirs and
     *  successors. We intend this dedication to be an overt act of
     *  relinquishment in perpetuity of all present and future rights to this
     *  software under copyright law.
     *  
     *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     *  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
     *  OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
     *  ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
     *  OTHER DEALINGS IN THE SOFTWARE.
     *  
     *  For more information, please refer to <http://unlicense.org>
     */
     
    public static ImageFormat GetImageFormat(this Image image)
    {
        if (image.RawFormat.Equals(ImageFormat.Bmp)) return ImageFormat.Bmp;
        else if (image.RawFormat.Equals(ImageFormat.Emf)) return ImageFormat.Emf;
        else if (image.RawFormat.Equals(ImageFormat.Exif)) return ImageFormat.Exif;
        else if (image.RawFormat.Equals(ImageFormat.Gif)) return ImageFormat.Gif;
        else if (image.RawFormat.Equals(ImageFormat.Icon)) return ImageFormat.Icon;
        else if (image.RawFormat.Equals(ImageFormat.Jpeg)) return ImageFormat.Jpeg;
        else if (image.RawFormat.Equals(ImageFormat.Png)) return ImageFormat.Png;
        else if (image.RawFormat.Equals(ImageFormat.Tiff)) return ImageFormat.Tiff;
        else if (image.RawFormat.Equals(ImageFormat.Wmf)) return ImageFormat.Wmf;
        throw new NotSupportedException("Invalid/Unsupported ImageFormat");
    }
 
    public static string ToBase64(this Image image)
    {
        var imageFormat = image.GetImageFormat();
        return image.ToBase64(imageFormat);
    }
 
    public static string ToBase64(this Image image, ImageFormat format)
    {
        var memoryStream = new MemoryStream();
        image.Save(memoryStream, format);
        var imageBytes = memoryStream.ToArray();
        string base64String = Convert.ToBase64String(imageBytes);
        return base64String;
    }
}