[chronojump] Fixed webcam ffmpeg snapshot for Linux (at least on developer laptop)

[Xavier de Blas <xaviblas src gnome org>]

commit f66e0ca3a06071e82ee07a7dd4c6e28dc8b88538
Author: Xavier de Blas <xaviblas gmail com>
Date:   Wed Nov 24 17:34:30 2021 +0100

    Fixed webcam ffmpeg snapshot for Linux (at least on developer laptop)

 src/webcam/webcamFfmpeg.cs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/src/webcam/webcamFfmpeg.cs b/src/webcam/webcamFfmpeg.cs
index 662bd1a40..56c6abaff 100644
--- a/src/webcam/webcamFfmpeg.cs
+++ b/src/webcam/webcamFfmpeg.cs
@@ -320,8 +320,13 @@ public class WebcamFfmpeg : Webcam
                else    //mac
                        parameters.Insert (i ++, videoDevice);
 
-               parameters.Insert (i ++, "-ss");
-               parameters.Insert (i ++, "0:0:2");
+               //on Linux, at least at developer laptop, -ss is not working
+               if(os != UtilAll.OperatingSystems.LINUX)
+               {
+                       parameters.Insert (i ++, "-ss");
+                       parameters.Insert (i ++, "0:0:2");
+               }
+
                parameters.Insert (i ++, "-frames");
                parameters.Insert (i ++, "1");
                parameters.Insert (i ++, Util.GetWebcamPhotoTempFileNamePost());