A first pass of the encoder finds out the "scene changes", or frames that differer for more than a certain % from the previous one. On the encoder side, each frame is converted to the YUV12 colorspace, divided in static blocks of 8x8 pixels (so you get up to 30x20 blocks on a GBA screen). This first version was extremely simple: it used fixed 4x4 pixels codebooks. There really existed 3 versions of Caimans codec: The caimans codec, the caimans codec pro and the caimans codec for DS. I'm really grateful that you are still talking about this codec after so many years, but it really was nothing fancy and I'm sure that you guys can now do much better than that humble Italian bedroom coder. That said, after all these years, I think it's fine to give a very high level description of the techniques that were used. The websites are still up an running as a form of nice memory, but really the service is no more. I eventually sold my IP to Activision (in 2007, I think) and thus I cannot release the encoder (not that I would know where to find the source code any more). It was probably the last time I had so much fun developing something, and I have fond, albeit distant memories of it. It evolved into a commercial project, but the drive behind it never ceased to be the same one that brings you guys here: to have some fun. Caimans codec was born out of an experiment and my will to learn how to develop for the GBA. A quick search took me here, so I thought I would spend some time to answer your questions.īut first I have to say that, as most of you probably understood, I've been away from the GBA for quite some years, so please forgive me if some memories are blurred. I was cleaning up my secondary email accounts and I found recent inquiries about the GBA Caimans codec. Sorry if I'm coming back to you after so long. And no, WiFi on the DS won't do, as I'm hoping for a 600+ foot range. If needed, depending on the transceiver chip/module, I could probably get up to 256,000 baud. I'm not sure whether I could interface an RF transceiver to a DS's slot 1 (definitely not slot 2.) RS-232 at 115,200 baud is the datarate I'm hoping to achieve. On second thought, the demos play very glitchy on VisualBoyAdvance, audio and video don't match on the GBA, and the video is nonfunctional on the DS (in GBA mode.) Some demo, if you ask me.but it's mostly there.īTW, this project isn't for the DS because it doesn't have a link port. Does anyone here have source code, a library, or just some really good documentation? Or is there another codec that I should be considering?Īdmittedly, I can reverse-compile a Caimans Video Codec example download, although that's disrespectful, and doesn't make the encoder part any easier. However, the last activity on both of those websites is 2005.I haven't received a response, and don't really expect to. JPEG has been considered, although technically, that's not video (MJPEG, perhaps!) I did come across Tony Savon's Caimans Video Codec (also a version for the DS.) It looks very promising, and I sent Tony an e-mail on Monday. The encoder will be a Parallax Propeller, an 8-core 32-bit CPU running at 80MHz (=20MIPs/core.) I would like to make a wireless remote camera project for the GBA, and will need some compression to make the video framerate useable.
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