Best Jpeg Encoder for Silverlight 4.0

I want to convert Writablebitmap to Jpeg stream, and it looks like there is no platform support as well as I can see a bunch of opensource Encoder libraries on web, I want to get your opinion on which is the recommen开发者_开发知识库ded one in terms of performance and reliability.

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I made good experience with FJCore. I also blogged about it a while ago http://kodierer.blogspot.com/2009/11/convert-encode-and-decode-silverlight.html

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I've spent quite a bit of time with both FJCore and LibJpeg.Net. FJCore is easier to use, since it was ported over from Java, and has an object model that vaguely resembles what you'd expect to see in C#. However, LibJpeg.NET is by far the more complete library (it's based on the informally canonical libjpeg), and it's significantly faster as well. To give one example, FJCore uses a naive implementation of an inverse discrete cosine transform that involves something like 1024 multiplications and an additional 1024 additions for each 8x8 block. In contrast, LibJpeg.NET uses the high performance AAN algorithm which only takes 144 multiplications and 464 additions (see http://datasheets.chipdb.org/Intel/x86/MMX/MMX/AP528.HTM#AAN Algorithm). In addition, FJCore is fairly inefficient in how it uses memory, constantly recreating objects that could easily be re-used. At the same time, because FJCore has fewer optimizations, it's significantly easier to hack.

For my current project (which involves writing a video codec for Silverlight), I used FJCore as a starting point, fixed a whole bunch of its inefficiencies, replaced its IDCT algorithm with the one from LibJpeg.NET, and ended up with something that gave me about 10x the original performance.

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Ken why don't you submit your updated code to the FJCore source?

http://code.google.com/p/fjcore/