You'll need to adjust the size  settings for the image  wherever it's being
used (it's not clear to me from you description exactly where that is). It
sounds like the destination is using a fixed width/height.

My actual requirement is to place the image  in the webpart  page in one of its
webpart.

Usyually we place alll the images  in the _layouts/images folder and mention that
path in the image link  property of Image WebPart. So according to my requirement
i should upload  all the images in the picture  library and i must mention that
path for example the image1 is uploaded  in the picture library  right clicking on
its gives the properties,
now copy the url  "http://ipaddr/sites/<sitename>/<folder name>/<image name>.jpg"
this link we should mention in the image link of the image webpart.
here i have the problem.An image of any size(eg 250X340) is getting fixed to
167X117.
Is there any way to change the image size  in the picture library.
Its not possible to get the original  size of the image to get displayed.

The image  is not being resized in the Picture Library – one of 2 things are
happening:



1) The Image web part you are using to display the image is doing the
resizing by having fixed width/height parameters

2) You are using the URL for a display thumbnail version of the image
instead of the URL for the full size  from the Picture Library

your explanation helped me in rectifying the problem.
and you are right..i was taking the url  for image  with thumbnail format..but i
found there is a round about way to get the image link.

Yes, and as I said this is being done where the image  is displayed, not in the
picture library  itself. You need to check the width and height properties  in
the display location.