Save ImageBuffer in memory

[leoshusar]

Hi!

I'm creating a web server app and I need to send the current camera frame over HTTP.
However I haven't found an obvious way to get the frame JPG in memory without needing to unnecessarily save it to disk first.

Am I missing something or is is not possible?

Thank you!

[TIS-Tim]

I'm afraid saving images to memory is not supported right now.

Which programming language do you use?

[leoshusar]

Sorry, I'm working in C#.

Can I please make this a feature request then? I'd for now implement it through a temp file and later just change it to in memory, when it's available.

[TIS-Tim]

In C# there is a quite simple workaround if you have access to System.Drawing:

• Add reference to ic4dotnet.System.Drawing
• Call imageBuffer.CreateBitmapCopy() or .CreateBitmapWrap(), depending on whether the ImageBuffer already is in a format that System.Drawing.Bitmap can hold
• Use the Stream-overload of System.Drawing.Image.Save to save as a Jpeg in memory

Make sure to dispose the bitmap object afterwards, or you might run out of memory.

[leoshusar]

Thank you for your suggestion!

Unfortunately since it's a Windows only solution, it's not 100 % ideal for me.
I tried it anyway, just to be sure, and got a 'System.Drawing.Common is not supported on this platform.' exception.

[TIS-Tim]

Is writing to /tmp memory-only on your system?

That should be a quick way to write to "files" that are very fast to write and read.

[leoshusar]

I don't know yet what system it will be running on.
For now I'm just implementing a cross platform solution that should theoretically "just work" wherever I deploy it, be it Linux or Windows.

I mean I can make a different implementation for Windows using System.Drawing and for Linux using the /tmp (if it's using tmpfs). But since the native IC4 library already knows how to produce the jpeg, it would be nice to just be able to get it in memory instead of passing through a file (I don't know how hard this implementation would be, it at least sounds easy though).

[TIS-Tim]

You are totally right, it would be a nice addition. No promises though at this point.