How to load an arbitrary image from a BLOB stream into a TImage?

Question

If I understand it correctly, TImage.LoadFromFile determines the type of picture from the file extension.

Is there any way to detect the image type auto

Answer 1

See this SO answer for file content retrieval from header.

Or you can use our TSynPicture class, which will handle all kind of pictures (bmp/gif/tiff/jpg/png) using Gdi+ library, in one single class. So your TPicture can be this unique class, for any kind of picture. With less code overhead than the Jpeg or PNG Delphi units.

var Pic: TSynPicture;

Pic := TSynPicture.Create;
Pic.LoadFromStream(aStream); // will load bmp/gif/tiff/jpeg/png content
AImage.Picture.Graphic := Pic;
....