diff --git a/GreenshotPlugin/Core/CoreConfiguration.cs b/GreenshotPlugin/Core/CoreConfiguration.cs
index f6bc84ed7..51d09da11 100644
--- a/GreenshotPlugin/Core/CoreConfiguration.cs
+++ b/GreenshotPlugin/Core/CoreConfiguration.cs
@@ -237,6 +237,11 @@ namespace GreenshotPlugin.Core {
 		[IniProperty("MailApiBCC", Description = "The 'BCC' field for the email destination (settings for Outlook can be found under the Office section)", DefaultValue = "")]
 		public string MailApiBCC;
 
+		[IniProperty("OptimizePNGCommand", Description = "Optional command to execute on a temporary PNG file, the command should overwrite the file and Greenshot will read it back. Note: this command is also executed when uploading PNG's!", DefaultValue = "")]
+		public string OptimizePNGCommand;
+		[IniProperty("OptimizePNGCommandArguments", Description = "Arguments for the optional command to execute on a PNG, {0} is replaced by the temp-filename from Greenshot. Note: Temp-file is deleted afterwards by Greenshot.", DefaultValue = "\"{0}\"")]
+		public string OptimizePNGCommandArguments;
+
 		// Specifies what THIS build is
 		public BuildStates BuildState = BuildStates.UNSTABLE;
 
diff --git a/GreenshotPlugin/Core/ImageOutput.cs b/GreenshotPlugin/Core/ImageOutput.cs
index 4407a00da..9aaddd30c 100644
--- a/GreenshotPlugin/Core/ImageOutput.cs
+++ b/GreenshotPlugin/Core/ImageOutput.cs
@@ -29,6 +29,8 @@ using Greenshot.IniFile;
 using Greenshot.Plugin;
 using GreenshotPlugin.Controls;
 using Greenshot.Core;
+using System.Diagnostics;
+using System.Security.AccessControl;
 
 namespace GreenshotPlugin.Core {
 	/// <summary>
@@ -167,17 +169,25 @@ namespace GreenshotPlugin.Core {
 						throw new ApplicationException("No JPG encoder found, this should not happen.");
 					}
 				} else {
+					bool needsDispose = false;
 					// Removing transparency if it's not supported in the output
 					if (imageFormat != ImageFormat.Png && Image.IsAlphaPixelFormat(imageToSave.PixelFormat)) {
-						Image nonAlphaImage = ImageHelper.Clone(imageToSave, PixelFormat.Format24bppRgb);
-						AddTag(nonAlphaImage);
-						nonAlphaImage.Save(targetStream, imageFormat);
-						nonAlphaImage.Dispose();
-						nonAlphaImage = null;
-					} else {
-						AddTag(imageToSave);
+						imageToSave = ImageHelper.Clone(imageToSave, PixelFormat.Format24bppRgb);
+						needsDispose = true;
+					}
+					AddTag(imageToSave);
+					// Added for OptiPNG
+					bool processed = false;
+					if (imageFormat == ImageFormat.Png && !string.IsNullOrEmpty(conf.OptimizePNGCommand)) {
+						processed = ProcessPNGImageExternally(imageToSave, targetStream);
+					}
+					if (!processed) {
 						imageToSave.Save(targetStream, imageFormat);
 					}
+					if (needsDispose) {
+						imageToSave.Dispose();
+						imageToSave = null;
+					}
 				}
 
 				// If we used a memory stream, we need to stream the memory stream to the original stream.
@@ -204,7 +214,65 @@ namespace GreenshotPlugin.Core {
 				}
 			}
 		}
-		
+
+		/// <summary>
+		/// Write the passed Image to a tmp-file and call an external process, than read the file back and write it to the targetStream
+		/// </summary>
+		/// <param name="imageToProcess">Image to pass to the external process</param>
+		/// <param name="targetStream">stream to write the processed image to</param>
+		/// <returns></returns>
+		private static bool ProcessPNGImageExternally(Image imageToProcess, Stream targetStream) {
+			if (string.IsNullOrEmpty(conf.OptimizePNGCommand)) {
+				return false;
+			}
+			if (!File.Exists(conf.OptimizePNGCommand)) {
+				LOG.WarnFormat("Can't find 'OptimizePNGCommand' {0}", conf.OptimizePNGCommand);
+				return false;
+			}
+			string tmpFileName = Path.Combine(Path.GetTempPath(),Path.GetRandomFileName() + ".png");
+			try {
+				using (FileStream tmpStream = File.Create(tmpFileName)) {
+					LOG.DebugFormat("Writing png to tmp file: {0}", tmpFileName);
+					imageToProcess.Save(tmpStream, ImageFormat.Png);
+					if (LOG.IsDebugEnabled) {
+						LOG.DebugFormat("File size before processing {0}", new FileInfo(tmpFileName).Length);
+					}
+				}
+				if (LOG.IsDebugEnabled) {
+					LOG.DebugFormat("Starting : {0}", conf.OptimizePNGCommand);
+				}
+
+				ProcessStartInfo processStartInfo = new ProcessStartInfo(conf.OptimizePNGCommand);
+				processStartInfo.Arguments = string.Format(conf.OptimizePNGCommandArguments, tmpFileName);
+				processStartInfo.CreateNoWindow = true;
+				processStartInfo.RedirectStandardOutput = true;
+				processStartInfo.RedirectStandardError = true;
+				processStartInfo.UseShellExecute = false;
+				Process process = Process.Start(processStartInfo);
+				process.WaitForExit();
+				if (process.ExitCode == 0) {
+					if (LOG.IsDebugEnabled) {
+						LOG.DebugFormat("File size after processing {0}", new FileInfo(tmpFileName).Length);
+						LOG.DebugFormat("Reading back tmp file: {0}", tmpFileName);
+					}
+					byte[] processedImage = File.ReadAllBytes(tmpFileName);
+					targetStream.Write(processedImage, 0, processedImage.Length);
+					return true;
+				}
+				LOG.ErrorFormat("Error while processing PNG image: {0}", process.ExitCode);
+				LOG.ErrorFormat("Output: {0}", process.StandardOutput.ReadToEnd());
+				LOG.ErrorFormat("Error: {0}", process.StandardError.ReadToEnd());
+			} catch (Exception e) {
+				LOG.Error("Error while processing PNG image: ", e);
+			} finally {
+				if (File.Exists(tmpFileName)) {
+					LOG.DebugFormat("Cleaning up tmp file: {0}", tmpFileName);
+					File.Delete(tmpFileName);
+				}
+			}
+			return false;
+		}
+
 		/// <summary>
 		/// Create an image from a surface with the settings from the output settings applied
 		/// </summary>