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Qt-jambi-interest Archive, February 2007
supported image formats

Message 1 in thread

Hello,

I have a question. In my installation of qt jambi, the list of supported
image formats is bmp, pbm, pgm, png, ppm, xbm, xpm.
Can we expect anytime soon support for jpeg, gif, raw ?
javax.imageio.ImageIO is sooooo slow! That would be very welcome.

The code to generate the list:

            List<QByteArray> formats = QImageReader.supportedImageFormats();

            System.out.println("Supported formats by Qt jambi");
            for (int i=0; i<formats.size(); ++i) {
                System.out.println(formats.get(i).toString());
            }
Message 2 in thread

Hi, Bruno.

Bruno Janvier wrote:

> I have a question. In my installation of qt jambi, the list of 
> supported image formats is bmp, pbm, pgm, png, ppm, xbm, xpm.
> Can we expect anytime soon support for jpeg, gif, raw ? 
> javax.imageio.ImageIO is sooooo slow! That would be very welcome.


The file types jpeg and gif are included as plugins in the Qt Jambi 
package. If you set the environment variable QT_PLUGIN_PATH to 
"path/to/jambi/plugins" they should magically appear in the supported 
image formats (we'll see about making this more usable for deploying 
applications, but for the beta, I hope it's sufficient :-))

I am however not aware that there is a standardized raw image format. 
The QImage class has a constructor which takes raw data as input. 
Unfortunately, the documentation for this constructor seems to be broken 
at the moment. The function I'm referring to is:

    
http://doc.trolltech.com/qtjambi-1.0/com/trolltech/qt/gui/QImage.html#QImage(byte[], 
int, int, com.trolltech.qt.gui.QImage.Format)

It takes the data as an array of bytes, the width and height of the 
image, and an enum indicating how the raw data is stored. The possible 
enum values are here:

    
http://doc.trolltech.com/qtjambi-1.0/com/trolltech/qt/gui/QImage.Format.html#enum_constant_summary

Does this help?


-- Eskil
Message 3 in thread

On Friday 16 February 2007 09:44, Eskil A. Blomfeldt wrote:
> I am however not aware that there is a standardized raw image format.
Assuming you are referring to the camera format 'raw'. You should probably 
take a look at 'dcraw' which is a small application that can convert raw to 
any other file format.
Its used across the industry to be able to parse raw files.

http://freshmeat.net/projects/dcraw/
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Message 4 in thread

Thanks to Ekil and Thomas. Very informative indeed.
I was making reference to the raw camera format, so great link indeed.


Thomas Zander a écrit :
> On Friday 16 February 2007 09:44, Eskil A. Blomfeldt wrote:
>   
>> I am however not aware that there is a standardized raw image format.
>>     
> Assuming you are referring to the camera format 'raw'. You should probably 
> take a look at 'dcraw' which is a small application that can convert raw to 
> any other file format.
> Its used across the industry to be able to parse raw files.
>
> http://freshmeat.net/projects/dcraw/
>