[Gdal-dev] GDAL, JPIP and OpenEV

[Norman Barker]

-----Original Message-----
From: fwarmerdam at gmail.com [mailto:fwarmerdam at gmail.com]On Behalf Of
Frank Warmerdam
Sent: Wednesday, January 11, 2006 5:16 PM
To: Norman Barker
Cc: gdal-dev at lists.maptools.org
Subject: Re: [Gdal-dev] GDAL, JPIP and OpenEV


On 1/11/06, Norman Barker <nbarker at rsinc.com> wrote:
> Is is possible that you could explain how to use a URL such as jpip://149.171.92.175/meteora.jp2 (which I grabbed from the Kakadu website) with GDAL and OpenEV please?

Norman,

I think you just use it directly.  I just tried it with the FWTools
build and get:

N:\pkg\dstile-0.2>gdalinfo jpip://149.171.92.175/meteora.jp2
ERROR 4: JPIP Protocol not supported by GDAL with Kakadu 3.4 or on Unix.
GDALOpen failed - 4
JPIP Protocol not supported by GDAL with Kakadu 3.4 or on Unix.

But if you build with a Kakadu 4.x it ought to work, at
least to some degree.

>
> Since OpenEV implements a display mechanism of rendering the data with a time phase, could it be easily adapted to progressive display?

I'm not sure what you mean about rendering with
a time phase.  Do you just mean support improving
display over time as more data is loaded?

It cannot be easily adapted to support progressive display.
But if you really wanted to do, the trick would be to get it
to load reduced resolution data in a first pass for some datasets.

Best regards,


Hi Frank,

thanks for the advice, that is very helpful regarding the URL connectivity with GDAL.

I was thinking of time based display in the first instance, but that is a little different to progressive display which
builds on the existing data, I am going to have to think about it!  A JPIP client that is open source would be useful.  I would quite like to do this with OpenEV if possible, the high level language makes this appealing. Do you have any advice?

Many thanks,

Norman Barker