GhostScript convert PDF to image

Question

I followed this tutorial :

https://www.c-sharpcorner.com/blogs/convert-pdf-file-into-image-filepngjpgjpeg-using-ghostscript

 

public void ExtracImagesFromPdf(string fileNameResultDirectory)

{

GhostscriptPngDevice img = new GhostscriptPngDevice(GhostscriptPngDeviceType.Png16m);

img.GraphicsAlphaBits = GhostscriptImageDeviceAlphaBits.V_4;

img.TextAlphaBits = GhostscriptImageDeviceAlphaBits.V_4;

img.ResolutionXY = new GhostscriptImageDeviceResolution(200, 200);

img.InputFiles.Add(fileNameResultDirectory);

//img.Pdf.FirstPage = 1;

//img.Pdf.LastPage = 1;

img.PostScript = string.Empty;

img.OutputPath = @"C:\Users\name\Desktop\images\Result";

img.Process();

 }

I get this error: Ghostscript.NET.GhostscriptAPICallException: 'An error occured when call to 'gsapi_init_with_args' is made: -100'

 

My PDF has more than page.