Hex to Binary convert

Question

I have converted my jpeg file as HEX code through hex converter.

Now how to convert that hex to binary and save as Jpeg file on disk.

Like:

var declared as Hex code and then convert that var hex code to binary and save on disk ?

Edit:

Var 
  myfileHex := 'FAA4F4AAA444444'; // long as HEX code of my JPEG 

function HexToBin(myfileHex): string;
begin    
  // Convert Hex to bin and save file as...
end; 

Answer 1

Delphi already has HexToBin (Classes) procedure, since at least D5.
Try this code:

procedure HexStringToBin;
var
  BinaryStream: TMemoryStream;
  HexStr: AnsiString;
begin
  HexStr := 'FAA4F4AAA44444';
  BinaryStream := TMemoryStream.Create;
  try
    BinaryStream.Size := Length(HexStr) div 2;
    if BinaryStream.Size > 0 then
    begin
      HexToBin(PAnsiChar(HexStr), BinaryStream.Memory, BinaryStream.Size);
      BinaryStream.SaveToFile('c:\myfile.bin')
    end;
  finally
    BinaryStream.Free;
  end;
end;

---

The same could be done with any binary TStream e.g. TFileStream.