Read image dimensions w/o loading to memory

[emars]

Greetings,
I am working with very large bitmaps in the 11,000x17,000 range and I
need to read the image dimensions (in pixels) in my app. Windows XP
can list dimensions as easily as time/date or file size as one of the
details in the file explorer, how can I do this with my simple C# app?

I have tried loading it as a nonvisible picturebox:
picturebox.Visible=false;
I have tried loading it into a bitmap and reading dimensions from
there:
img = (Bitmap)Image.FromFile(openImg);
width = img.Width;
height = img.Height;

These are very memory costly, and I want a BETTER way!

opensource libraries such as imagemagick have this functionallity but
I have not been able to catch their output yet, has anybody tried this
library to success?

Thanks all

 

[Ilya Tumanov [MS]]

You can open this file and read its header.

BMP header is well know, for example:
http://astronomy.swin.edu.au/~pbourke/dataformats/bmp/
If you need to support other formats, they have headers too.

Best regards,

Ilya

This posting is provided "AS IS" with no warranties, and confers no rights.
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