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copied!<p>You can't use <code>TPicture.LoadFromFile</code> if you don't know what format the graphic has, as this method uses the file extension to determine which of the registered graphic formats needs to be loaded. There's a reason that there is no matching <code>TPicture.LoadFromStream</code> method.</p> <p>An external library which can examine data and determine the graphic format at runtime would be the best solution. You could use the <a href="http://www.efg2.com/Lab/Library/Delphi/Graphics/FileFormatsAndConversion.htm" rel="noreferrer">efg page</a> as a starting point of your research.</p> <p>A quick and dirty solution is to try the few formats you need to handle until one succeeds:</p> <pre><code>function TryLoadPicture(const AFileName: string; APicture: TPicture): boolean; const GraphicClasses: array[0..3] of TGraphicClass = ( TBitmap, TJPEGImage, TGIFImage, TPngImage); var FileStr, MemStr: TStream; ClassIndex: integer; Graphic: TGraphic; begin Assert(APicture <> nil); FileStr := TFileStream.Create('D:\Temp\img.dat', fmOpenRead); try MemStr := TMemoryStream.Create; try MemStr.CopyFrom(FileStr, FileStr.Size); // try various for ClassIndex := Low(GraphicClasses) to High(GraphicClasses) do begin Graphic := GraphicClasses[ClassIndex].Create; try try MemStr.Seek(0, soFromBeginning); Graphic.LoadFromStream(MemStr); APicture.Assign(Graphic); Result := TRUE; exit; except end; finally Graphic.Free; end; end; finally MemStr.Free; end; finally FileStr.Free; end; Result := FALSE; end; </code></pre> <p><strong>Edit:</strong></p> <p>The <a href="http://www.soft-gems.net/index.php?option=com_content&task=view&id=13&Itemid=33" rel="noreferrer">GraphicEx library</a> has an example <em>convert</em> that uses</p> <pre><code>GraphicClass := FileFormatList.GraphicFromContent(...); </code></pre> <p>to determine the graphic format. This seems very similar to the VB6 way of doing this that you mention. Maybe you can use this library for your purpose.</p>

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