How to get DPI from JPG image?


How do I get the DPI at JPEG image?


You would first use this forum post to confirm that the image is in fact JPEG image, by looking for DCTDecode.

Once you have confirmed, you want to get the raw stream, using Obj.GetRawStream(true)

That gives you the JPG image in memory, which may or may not contain the DPI metadata, but either way you would load/open in any image processing API you have available to you.