JPEG 2000

I came accross some information that indicated JPEG 2000 as a camparable image compresion to MrSIDS. I found one brief article that was listed but would like more information if anyone could point me in the right direction.

http://www.jpeg.org/apps/sensing.html

Is there any indication that standards will include JPEG 2000?

creed's picture

JPEG 2000

Norman -

Funny you should ask. Turns out that the current WCS Revision Working Group has been discussing JPIP as a possible output type resuting from a WCS request. In terms of contributing, there are probably several ways:

1. Join the OGC at the basic entry level and contribute directly.
2. Send requirements to me and I will pass them onto the WCS RWG. Not optimal but can work.
3. Stand up reference server implementations that anyone in the community can access to test clients. This is always agood thing!

Let me think some more.

Regards

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JPEG 2000

Hi Carl,

thanks for your quick answer, I see your point, and from the ISO Jpeg2000 spec we can specify a mime type of image/jpip-stream (or image/jpt-stream depending on which version of Kakadu or RSI's IAS your are using) to specify a jpip stream, so I guess a WMS is ok.

I am not deliberately being contrary, but I would like to discuss this some more. Certainly with the idea of GML in Jp2 for serving coverage data, as well as just maps (Jpeg2000 supports lossless compression) I think we need a way that is more use to scientists.

I am fairly convinced of the benefits of using a WFS for this, and I see the WMS as a quick fix (but very useful, I should be able to prototype this very quickly). What is the current state of developments with serving GML in Jp2 through OGC servers, are the specifications undergoing change after the approval of GML in JP2?

I see on Ron Lake's blog (http://geoweb.blog.com/464359/) a discussion on JPIP / WFS. Do you have any opinion on the best way to go?

When I think of the possibilities for JPIP within OGC implementations I think of

1) Coverage (netCDF springs immediately to mind)
2) WMS, WFS (as discussed above)
3) Vector and Map Streaming

Is there a way I can contribute to this development, or perhaps find more info? I have been funded to develop a server where OGC GML in Jp2 is the base format with JPIP streaming, and it would be nice to 'get this right'.

thanks,

Norman

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creed's picture

JPEG 2000

This from the WMS editor:

With WMS you are permitted to send any appropriate format in response to
a GetMap request as long as you MIME-type it correctly. Indeed, I have
lately been privately offering "text/plain" and "text/html" options on
my servers to provide basic metadata about the image to my clients
(e.g., http://map05.gsfc.nasa.gov/cgi-bin/viewer.cgi).

The following is barely-informed speculation on my part:

I do not find any definition of 'image/jpip' as a legal type (I see only
image/jp2 and image/jpx in IETF RFC 3745, for example). If it is the
case that JPIP means JPEG2000-format data transmitted using an
interactive protocol, then perhaps the MIME type must be image/jp2 and
(if necessary) some other technique must be used to indicate that the
image is "JPIP-enabled" rather than "plain" JPEG2000. Possible other
techniques are (1) a vendor-specific parameter in the GetMap request or
(2) different URL prefixes for JPIP and non-JPIP content or (3) MIME
type extension such as "image/jp2; procotol=JPIP".

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creed's picture

JPEG 2000

Norman -

Let me check.

Regards

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JPEG 2000

Hi Carl,

I am doing a lot of work with Jpeg2000 / JPIP within an OpenGIS environment, trying fit JPIP into an OGC framework. I came to the conclusion that a WFS and a GML property with an xlink:href attribute was the way to go to give a client a URL to retrieve the data.

I am very interested to hear how this was done with a WMS, can you elaborate please? I guess with a WMS you could set the mime-type on the getmap response to image/jpip and kick off the JPIP viewer. I would be interested in seeing a working example of this.

Also GML in Jp2 spec does more than just make an image geographic, it should also provide metadata about the actual binary data (in the case of netCDF say), and perhaps more exciting is the enabling feature (GML) streaming since you can set arbitrary XML boxes within the Jp2 file. I would be grateful if we could open up a discussion on this, perhaps in this forum.

Many thanks,

Norman

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creed's picture

JPEG 2000

Brad -

Based on some discussions I had yesterday with an OGC member, the answer is that you can do this now. I have not read the relevant sections of the WMS 1.3 specification, but this member was telling me how they have enabled JPEG 2000 as well as JPIP as valid responses from a WMS request.

Check out the use of the FORMAT parameter in the GetMap request. The obvious issue is that you need to be sure that the server(s) understand and support the use of JPEG2000 - which the client should know based on the GetCapabilities response.

Cheers

Carl

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JPEG 2000

Carl,

My question would be will OGC include JPEG 2000 as another WMS supported standard for sending map images to a web client just like the spec supports JPEG, PNG, GIF, TIFF, etc? Transmission performance should be improved I would have thought?

Cheers, Brad...

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creed's picture

JPEG 2000

Jiann-Yeou -

The OGC does not work on Image Compression Standards. The work we have done with JPEG 2000 was to develop an GML application schema that can be part of a JPEG 2000 payload. This work has resulted in a newly adopted OpenGIS Implementation Specification titled "GML in JPEG 2000 Specification". This OpenGIS Implementation specification defines the means by which the OGC Geography Markup Language (GML) is to be used within JPEG 2000 images for geographic imagery. Further, the specification also provides packaging mechanisms for including GML within JPEG 2000 data files as well as specific GML application schemas to support the encoding of images within JPEG 2000 data files.

By way of further information, JPEG 2000 is the latest series of standards from the JPEG committee. The original standard for digital images (IS 10918-1, popularly referred to as JPEG) was developed 15 years ago, and with the major increase in computer technology since them, and lots of research, it was felt to be time for a new standard capable of handling many more aspects than simply making the digital image files as small as possible. JPEG 2000 uses 'wavelet' technology. and as well as being better at compressing images (up to 20 per cent plus), it can allow an image to be retained without any distortion or loss. Simply sending the first part of such a 'lossless' file to a receiver can result in a lossy version appearing (like present JPEG) - but continuing to transmit the file results in the fidelity getting better and better until the original image is restored.

Now, ECW is also a wavlet compression standard developed by Earth Resource Mapping. ECW and JPEG 2000 are compatible. Therefore, I believe ERM would be the correct organization to ask questions regarding the use of GML, ECW, and JPEG 2000.

Regards

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How about ECW image format

Does OGC plan to include ECW image format in the future ?

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creed's picture

JPEG 2000

Doug -

JPEG 2000 is an international standard. The ISO/IEC JTC 1 work items for JPEG 2000 are allocated to SC 29/WG 1 ( http://www.itscj.ipsj.or.jp/sc29/29w42901.htm#JPEG%202000)

There is also a JPEG organization and a web site (http://www.jpeg.org) where you can find considerable information regarding JPEG and JPEG 2000.

JPEG 2000 is a new image coding system that uses state-of-the-art compression techniques based on wavelet technology. Its architecture should lend itself to a wide range of uses from portable digital cameras through to advanced pre-press, medical imaging and other key sectors.

In terms of the relationship between JPEG 2000 and MrSID, that discussion is best left to others.

Also, FYI, a number of OGC are working to define a common GML schema for storing geo-location information for imagery, within the JPEG2000 format. The space for the GML Schema was allocated by the JPEG 2000 SC 29 WG.

Regards

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