// Construct a new DICOM dataset and populate required attributes
DicomDataSet ds = new DicomDataSet();
                    
ds.Add(Keyword.Rows, 434);
ds.Add(Keyword.Columns, 636);
ds.Add(Keyword.BitsAllocated, 8);
ds.Add(Keyword.BitsStored, 8);
ds.Add(Keyword.HighBit, 7);
ds.Add(Keyword.SamplesPerPixel, 3);
ds.Add(Keyword.PixelRepresentation, 0); 
ds.Add(Keyword.PhotometricInterpretation, "RGB");
ds.Add(Keyword.PlanarConfiguration, 0);     
ds.Add(Keyword.NumberOfFrames, frames);
                
UID transferSyntax = TransferSyntaxes.JPEG2000Lossless;
IDecompressor myDecompressor = new JpegLosslessDecompressor(); // Implement your own IDecompressor
Stream pixelData = File.OpenRead("pixeldata.data");
                    
ds.SetDicomCodec(transferSyntax, myDecompressor, pixelData);
                    
// Example JpegLosslessDecompressor
                    
public class JpegLosslessDecompressor : IDecompressor
{
    public bool NeedsPlanarConfigTransform => false;
    
    public void Decompress(DecompressionArguments args)
    {
        using (var ms = new MemoryStream())
        {
            var srcBytes = new byte[args.SourceStream.Length];
            args.SourceStream.Read(srcBytes, 0, srcBytes.Length);
            using (JpegLSDecoder decoder = new JpegLSDecoder(srcBytes))
            {
                var decodedBytes = decoder.Decode();
                Buffer.BlockCopy(decodedBytes, 0, args.DestinationArray, 0, decodedBytes.Length);
            }
        }
    }
    
    public string DecompressedPhotometricInterpretation(DicomObjects.DicomDataSet parent)
    {
        return parent[Keyword.PhotometricInterpretation].Value.ToString(); 
    }
    
    // ETC.
}