Re: scaling a jpeg on a web server

[Michael Fortin <pommele@mindspring.com>]

Jerzy,
Thanks for the suggestions.  That wasn't exactly what I was looking for 
but it helped quite a bit anyway.
Under java 1.4.0 there is the init flag -Djava.awt.headless=true that 
was an easy short term solution.  Jai would be the smatter long term 
solution but the api is a bit confusing and poorly documented.

Thanks for the tip.

Michael


On Sunday, September 15, 2002, at 01:07 PM, Jerzy Puchala wrote:

> Hi,
>
> I understand that you would like to resize your uploaded picture and
> save. Next the server will show it to the user which is browsing the
> page. If this is true you do not need displaying ability of AWT/SWING
> - you do like to convert picture - not display it.
>
> I went thrue this same path. The AWT/SWING is the worst and slowest
> what you can use. They are prepared for display!! not for manipulating
> the picture. For using above you have to have X server runing (and you
> IMHO definitly do not want to depend on this your application).
>
> I strongly recomend to take a look into JAI.
> http://java.sun.com/products/java-media/jai/
>
> It is flying and most of all it not depends on X server.
>
> On the page:
> http://www.yourek.org/grafika/imageDimension.html
>
> there is an example around your question - it is Polish Java FAQ - 
> sorry
> it is in Polish but this was whole purpouse of it :)
>
> Anyway it shows how to receive picture size. On top you have the code
> which uses AWT and on the bottom this same which uses JAI.
>
> If you will have any additional questions please send me an email
>
> Best of luck
>
> Jerzy Puchala
>
>
> On Sat, 14 Sep 2002, Michael Fortin wrote:
>
>> Hello,
>> 	Does anyone have any experience resizing or manipulating jpeg images
>> on a web server?  I'm trying to scale an uploaded image but I get the
>> following error in production:
>> java.lang.InternalError: Can't connect to X11 window server using
>> ':0.0' as the value of the DISPLAY variable.
>>          at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)
> [...]
>>
>> it would appear that there is no computer monitor or display to
>> initialize so the default toolkit fails.  Is there a way to scale an
>> image without using the Toolkit?  I can't find any libraries that 
>> don't
>> use the it.
>>
>> Any suggestions would be greatly appreciated.
>>
>> Michael
>>
>
>
>
> -- 
> +--------------------------------+
> |         Jerzy Puchala          |
> +--------------------------------+
> |       jerzypuc@scdi.com        |
> +--------------------------------+
>