String compression
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Well, I need to write a program that send huge amount of text by http... and i want to compress it before sending I just want to know if someone have some API (free or not) who can return me the compressed string so i can send the compress strin
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Well, I need to write a program that send huge amount of text by http... and i want to compress it before sending I just want to know if someone have some API (free or not) who can return me the compressed string so i can send the compress strin
Hey Patrice, I'm sure there are about 500 compression libraries available on the net, but if you're looking for a commercial solution (with nice things like intellectual property rights and patent protection... usually of concern to corporate dev's), you should have a look at our Ultimate Toolbox. Here's a link to the docs on the COXCompressor class, one of the 300 or so in the kit. http://www.dundas.com/docs_online/toolbox/file/COXCompressor/overview.htm http://www.dundas.com
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Well, I need to write a program that send huge amount of text by http... and i want to compress it before sending I just want to know if someone have some API (free or not) who can return me the compressed string so i can send the compress strin
Take a look at zlib - really great stuff. ftp://ftp.freesoftware.com/pub/infozip/zlib/ Wanderle
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Well, I need to write a program that send huge amount of text by http... and i want to compress it before sending I just want to know if someone have some API (free or not) who can return me the compressed string so i can send the compress strin
But..., i thought modems do compress data since the time of the "2400/MNP5" modems. Am i wrong? I can remember some BBS stating in their welcome messages about their new 2400 modems with MNP5! which is translated to 'Compression' & 'Error Correction'. As about me i had a plain 2400bps which was cheaper.
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Hey Patrice, I'm sure there are about 500 compression libraries available on the net, but if you're looking for a commercial solution (with nice things like intellectual property rights and patent protection... usually of concern to corporate dev's), you should have a look at our Ultimate Toolbox. Here's a link to the docs on the COXCompressor class, one of the 300 or so in the kit. http://www.dundas.com/docs_online/toolbox/file/COXCompressor/overview.htm http://www.dundas.com
Are there any intellectual property issues around Zlib (http://www.info-zip.org/pub/infozip/zlib/)? The ZLib license gives explicit permission to use with commercial software with almost no restrictions. There are no GPL-like issues that require you to give away your own code or even to supply the customer with Zlib source. You do not even need to mention ZLib in connection with your product. The algorithms in Zip have been carefully researched to be patent-free, which is why PNG, which uses ZIP compression is being promoted as a royalty-free alternative to GIF. Zlib is also an official part of the Java JDK 1.1: it is the engine used to compress Java JAR files and is present as a class in the core Java library. I would point out that ZLib is so good that Dundas's competitors Stingray simply include an outdated version of the free ZLib as the compression engine for their Objective Toolkit and Objective Toolkit Pro. I trust that Dundas has more class than that. Sometimes the tech support you get with a commercial library is definitely worth the price, but unless I am missing something here, I don't think the intellectual property issues are as great a concern as you suggest
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Are there any intellectual property issues around Zlib (http://www.info-zip.org/pub/infozip/zlib/)? The ZLib license gives explicit permission to use with commercial software with almost no restrictions. There are no GPL-like issues that require you to give away your own code or even to supply the customer with Zlib source. You do not even need to mention ZLib in connection with your product. The algorithms in Zip have been carefully researched to be patent-free, which is why PNG, which uses ZIP compression is being promoted as a royalty-free alternative to GIF. Zlib is also an official part of the Java JDK 1.1: it is the engine used to compress Java JAR files and is present as a class in the core Java library. I would point out that ZLib is so good that Dundas's competitors Stingray simply include an outdated version of the free ZLib as the compression engine for their Objective Toolkit and Objective Toolkit Pro. I trust that Dundas has more class than that. Sometimes the tech support you get with a commercial library is definitely worth the price, but unless I am missing something here, I don't think the intellectual property issues are as great a concern as you suggest
Hi Jonathan, Although I don't believe that any intellectual property issues exist with zLib, who legally warrants that there aren't any? Can you sue the authors or the legal counsel that reviewed the library if they were wrong? FWIW, I think Intellectual property issues are of paramount concern. Ask any corporate counsel in any corporation with a worth of more than $20M, people lose a lot of sleep over this (and corporations spend a lot of time in court over this). Particulary in the areas of compression, encryption, delta comparisons, etc. Although our library doesn't use zLib, I don't see any problem in Stingray utilizing a standard library in their toolkit, unless they aren't being up-front about it. Simply cleaning up the interface and making it easier to use with MFC would be of value, and certainly worth the $495/70 classes = $7 that a developer would pay for it, considering that they *are* warranting it, and are legally liable if there in-fact is an intellectual property issue. In the end of course it is personal choice. Far too often however our fellow developers put code into their applications without thought of its origin, of warranties, and of these legal issues and put themselves and their employers at risk. I have no doubt that companies that are serious about using libraries like zLib (such as Microsoft or AOL) solicit an outside legal opinion on intellectual property issues before including it in anything important. That's how they get their intellectual property protection, from their legal counsel (if they are wrong they can sue their lawyers.) Anyway, legal stuff gives me a headache :) In short, I heartfully say that it is not a non-issue!