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riccohb

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JPG/GIF images

I'm sure this question is a piece of cake, but I can't seem to find any information on it anywhere.

I want to display jpg and gif images within an application, but TImage only seems to be able to handle bitmaps. What do I use to display jpgs and gifs?
Avatar of kretzschmar
kretzschmar
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get the gifimage-component from melander or
get graphicEx from mike lischke

links may follow


jpg, should be no problem,
just add the unit jpeg into the uses-clause

meikl ;-)
Avatar of riccohb
riccohb

ASKER

Thanks for getting back to me.

I've added JPEG to the uses clause of the unit, but I get an EInvalidGraphic error 'Unknown picture file extension (.jpg)' when the code gets to the line

imgPics.Picture.LoadFromFile(lbxPics.Items[i]);

where imgPics is TImage and lbxPics is a list box. When the user double clicks an item in the list box the code iterates through the list box items and tries to load the one corresponding to ItemIndex i.
ASKER CERTIFIED SOLUTION
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Cesario Lababidi
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Hi,

uses jpeg;

var
  JPegImage : TJpegImage;
begin
  JPegImage := TJPegImage.Create;
  JPegImage.LoadFromFile(lbxPics.Items[i]);
  imgPics.Picture.Assign(JPegImage);
  JPegImage.Free;
end;

Regards, Geo
yep, geo,
this is a workaround,

but atleast it should be enough to add the jpeg-unit
into the uses calause, as the jpeg-unit registers itself
to the supported graphicformats

maybe riccohb did not a full rebuild of the app

meikl ;-)
You are right, meikl. It should be. Perhaps it's a Delphi version problem.
mmm, i would also, as kretzchmer sugested "graphicEx from mike lischke" not only is that a quality piece of software, but it lets you do neat stuff with many other file formats, including ONG's which, for almost everything are much nicer then GIF's ;p

GL
Mike
Hello

For jpegs just add jpeg.pas to your uses and use the following statement to register the JPG format for a TImage.

Image1.Picture.RegisterFileFormat('JPG','JPEG Bitmap',TJPEGIMAGE);

After you do this, you can load the image from a stream or file.



One Bad thing about gif's ,you have to pay royalties to unisys for reading and/or writing gifs,read here :

http://216.239.39.100/search?q=cache:V56QJZeuPAMC:www.unisys.com/unisys/lzw/+unisys&hl=en


I rather perfer PNG,
here's where to get component free with source:

http://pngdelphi.sourceforge.net/download.php?goto=pngimage142.zip&file=pngimage.txt

read the help file for instructions to install and use

Good luck!
a sample, with graphicEx


Function TForm1.DisplayImage(AStream : TStream; AExtension : String) : Boolean;
Var
  //Extended Graphicformats
  AExGraphicClass: TGraphicExGraphicClass;
  AExGraphic: TGraphicExGraphic;
  //Standard Graphicformats
  AGraphicClass : TGraphicClass;
  AGraphic : TGraphic;
  OldPosition : Integer;
begin
  Result := False;  //do as that cannot be loaded
  If Assigned(AStream) then
  try
    OldPosition := AStream.Position;
    try
      AStream.Position := 0;  //Remember Streams Position
      //Check for Extended Graphicformats
      AExGraphicClass := GraphicEx.FileFormatList.GraphicFromContent(AStream);
      if AExGraphicClass <> Nil then
      begin
        AExGraphic := AExGraphicClass.Create;
        try
          //Load Extended Graphicformats
          AExGraphic.LoadFromStream(AStream);
          Image1.Picture.Graphic := AExGraphic;
          Result := True;
        finally
          AExGraphic.Free;
        end;
      end
      else
      begin
        //Check for Standard Graphicformats
        AGraphicClass := GraphicEx.FileFormatList.GraphicFromExtension(AExtension);
        if AGraphicClass <> Nil then
        begin
          AGraphic := AGraphicClass.Create;
          try
            //Load Standard Graphicformats
            AGraphic.LoadFromStream(AStream);
            Image1.Picture.Graphic := AGraphic;
            Result := True;
          finally
            AGraphic.Free;
          end;
        end;
      end;
    finally
      AStream.Position := OldPosition;
    end;
  except
    Raise;
  end;
end;

meikl ;-)
about graphicEx

http://www.delphi-gems.com/Graphics.html
(free for nonComercial use)

additional supported grafikformats
(just taken from the site)

TIFF images (*.tif; *.tiff), extended base line implementation
- 1..16 bits per sample
- indexed, grayscale, RGB(A), CMYK, L*a*b*
- uncompressed, packed bits, LZW, CCITT T.4, Thunderscan, Deflate, new style JPEG

GFI fax images (*.fax), uses TTIFFGraphic to read

SGI images (*.bw, *.rgb, *.rgba, *.sgi)
- 1..16 bits per sample
- indexed, grayscale, RGB(A)
- uncompressed, RLE
 
Autodesk images files (*.cel; *.pic) old style only
- 8 bits per sample, indexed and uncompressed

Truevision images (*.tga; *.vst; *.icb; *.vda; *.win), write support included
- 5 and 8 bits per sample
- grayscale, indexed, 15 bits RGB (555), 24 bits RGB(A)(888)
- uncompressed, RLE

ZSoft Paintbrush images (*.pcx, *.pcc; *.scr)
- 1..8 bits per sample
- grayscale, indexed, RGB
- uncompressed, RLE
 
Kodak Photo-CD images (*.pcd)
- 8 bits per sample in YCbCr in any resolution (192 x 128 up to 6144 x 4096)
- Portable pixel/gray map images (*.ppm, *.pgm, *.pbm)
- 1 and 8 bits per sample
- grayscale, indexed, RGB uncompressed
 
Dr. Halo images (*.cut, *.pal)
- 8 bits per sample indexed, RLE compressed

CompuServe images (*.gif)
- 1, 4, 8 bits per sample indexed, LZW compressed

SGI Alias/Wavefront images (*.rla, *.rpf)
- 8 bits per sample RGB(A), RLE compressed

Standard Windows bitmap images (*.bmp, *.rle, *.dib)

Photoshop images (*.psd, *.pdd)
- 1, 8, 16 bits per sample
- indexed, RGB, CMYK, CIE L*a*b*
- uncompressed and packed bits
 
Paintshop Pro images (*.psp)
- 1, 4, 8 bits per sample
- indexed, grayscale, RGB
- uncompressed, RLE and LZ77
- single-layered files only!

Portable network graphic images (*.png)
- 1, 2, 4, 8, 16 bits per sample
- indexed, grayscale alpha, RGB(A), LZ77 compressd
Avatar of riccohb

ASKER

Thank you.
;-) saw you posted a q for me
:-( -> :-)