# FFmpeg Command Line in Asp.Net Core

• ### Question

• User338455301 posted

Hi,

i want add text to video with ffmpeg ,

other command line is worked but for this code its not worked ? why ?

```    ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.CreateNoWindow = false;
startInfo.UseShellExecute = false;
startInfo.FileName = Path.Combine(Directory.GetCurrentDirectory(), "ffmpeg.exe");

//????????

startInfo.Arguments = "-i H://input.mp4 -vf drawtext=" + "fontfile =H://arial.tft: \\" +
"text = 'Stack Overflow': fontcolor = white: fontsize = 24: box = 1: boxcolor = black@0.5: \\" +
"boxborderw = 5: x = (w - text_w) / 2: y = (h - text_h) / 2" + " -codec:a copy H://output.mp4";

//????????

startInfo.RedirectStandardOutput = true;

try
{
using (Process process = Process.Start(startInfo))
{
process.WaitForExit();
}

}
catch (Exception ex)
{

throw;
}```

Sunday, September 15, 2019 7:54 AM

• User338455301 posted

i use \\ insted of // but its now worked.

` startInfo1.Arguments = "ffmpeg -i H:\\input.mp4 -vf "+'"'+ "drawtext =text='Super User':x=(w-text_w)/2:y=(h-text_h)/2:fontsize=24:fontcolor=white" + '"' + " -c:a copy H:\\out.mp4";`

• Marked as answer by Thursday, October 7, 2021 12:00 AM
Tuesday, September 17, 2019 4:33 AM

### All replies

• User-474980206 posted
If you are hosting in iis then the current directory is the iis hosting bin, not the project.
Sunday, September 15, 2019 4:22 PM
• User338455301 posted

i test it in local
i put a file  (input.mp4) in H:// and test this code but its not work ?
i have just problem with this code.

` "-i H://input.mp4 -vf "+'"'+ "drawtext =text='Super User':x=(w-text_w)/2:y=(h-text_h)/2:fontsize=24:fontcolor=white" + '"' + " -c:a copy H://out.mp4";`

Monday, September 16, 2019 10:31 AM
• User753101303 posted

Hi,

It's often easier to start from an actual error message rather then trying to guess from the code.

If windows try h:\\input.mp4 rather than // - it is \ in Windows and it needs to be escaped in C# unless using "verbatim" strings. You could also a permission error or some other problem for the generated options...

Monday, September 16, 2019 2:21 PM
• User338455301 posted

i use \\ insted of // but its now worked.

` startInfo1.Arguments = "ffmpeg -i H:\\input.mp4 -vf "+'"'+ "drawtext =text='Super User':x=(w-text_w)/2:y=(h-text_h)/2:fontsize=24:fontcolor=white" + '"' + " -c:a copy H:\\out.mp4";`

• Marked as answer by Thursday, October 7, 2021 12:00 AM
Tuesday, September 17, 2019 4:33 AM