c# - Trying to join two mp4 video files using ffmpeg but getting error -

i'm trying join 2 mp4 video files, i'm getting following error:

unable find suitable output format 'ffmpeg'.

ffmpeg: invalid argument

my code below:

processstartinfo startinfo = new processstartinfo(); startinfo.filename = "path ffmpeg"; startinfo.arguments = "ffmpeg -f concat -i "+path_to_text_file+" -c copy "+path_to_output_video; startinfo.useshellexecute = false; startinfo.redirectstandardoutput = true;         try         {             process process = process.start(startinfo);             while (!process.standardoutput.endofstream)             {                 console.writeline("process standard output : " + process.standardoutput.readline());             }         }         catch (exception e)         {             console.writeline(e.message);         } 

my input text file like

file '/path/to/input0' file '/path/to/input1' 

can point out i'm going wrong.

the first thing can see you're using "ffmpeg " part of argument. calling executable. when defining target filename. final command looks kinda this:

"\ffmpeg ffmpeg -f concat -i ...."

so if remove "ffmpeg" part argument , try again :-)