C# InMemoryCopy of Image file as StandardInput for process

Question

I am trying to create a copy of an image in memory and to use this as STDIN for a console process.

Create the InMemoryCopy:

using (FileStream fs = File.OpenRead(image))
{
   fs.CopyTo(inMemoryCopy);
}

Start process and input STDIN:

p.StartInfo.Arguments = " jpg:fd:0" +
   " -resize 500" +
   " \"" + tmpFile + "\"";

p.Start();
//Reads in pbm file.
using (var streamReader = new StreamReader(inMemoryCopy))
{
  p.StandardInput.Write(streamReader.ReadToEnd());
  p.StandardInput.Flush();
  p.StandardInput.Close();
}

Issue I encounter is that imagemagick noww does not recognise the file as image anymore? The file used is a .jpg but from the streamReader it seems not to be written into STDIN as valid Image file?

As I am a very much newbie, I googled and searched here to find an answer but could not figure this out.

How would I read an image file into memory and use this as STDIN in the console app (e.g. imagemagick).

Many thanks for any help!

Why are you trying to subvert imagemagick's ability to read files??? — Michael Bray, Jul 05 '13 at 00:28
@Michael Bray - I want to have one tmp copy of the file in memory and any changes from my different effects will only be applied to this copy. Once I am happy with the changes, I save the final file. this should avoid excessive writing/reading to the harddisk and improve performance. I am completely new to C#, so I am very happy about further comments. — user2551898, Jul 05 '13 at 22:55

score 2 · Accepted Answer · edited May 23 '17 at 11:50

2

StreamReader is a text reader. You probably want to write binary data to the stdin basestream. According to this: Can i put binary in stdin? C#.

You can do:

fs.CopyTo(p.StandardInput.BaseStream)

edited May 23 '17 at 11:50

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answered Jul 05 '13 at 00:40

fcuesta

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Many thanks for the link, it showed me the correct way. Great help! – user2551898 Jul 05 '13 at 22:51

C# InMemoryCopy of Image file as StandardInput for process

1 Answers1