As we've discussed before, a codec was needed with old-style analog video to capture and playback video. As we've also learned in the 10 most important features of DV: The codec sits in the camcorder or VCR. This is where video is encoded and decoded in real time. 

So why duplicate the codec on a board? Some Firewire developers, notably Adaptec, miro and  Radius asked themselves the same question. They looked into the matter and decided: Who needs a hardware codec?  You can't live without a hardware codec if you  want to encode or decode video in real time, but with DV, that's already done in the camcorder.  So why get a codec at all for DV? Because you need one to decompress the clips for editing, as described in Step 7 of the video editing workflow. For reasons which are beyond the scope of this article (we'll cover it at great length later), hardware codecs don't shine in this process. They may encode and decode in real time, but because so much data has to be sent across the bus to the board, decoded, sent back across the bus to memory and copied around, they actually can be quite slow.

CPUs on the other hand are getting faster and faster. Therefore, Adaptec, DPS, miro and Radius decided to implement the codec in software.   

Fast, who uses the Sony DVBK-1 hardware codec, and Matrox, who uses a chipset from Panasonic, decided to go the hardware route.  Sony's DVBK-1 is expensive (the part alone adds between $1500 to $2000 to the retail price). It basically is a dedicated, embedded DV computer module. It simplifies the writing of drivers, because it handles most of the hard work on-board.  Software-only codecs are hard to design and develop, but they cost next to nothing to reproduce. It's also much easier to add features to software codecs and their associated drivers. Customers can simply download the next version from the web.  

Soon, heated discussions ensued on who has the right and who has the wrong codec. Some even talked of a "codec war."  When Microsoft announced that they will ship a software DV codec (ironically developed by Matsushita, makers of the Panasonic hardware codec), and when Apple Computer announced that they would also ship a software DV codec with Quicktime 3, the hostilities calmed quite a bit. A representative of Fast even announced on rec.video.desktop that his company is investigating  at least a partial use of a software codec.   

Written mostly by Bertel Schmitt.  Maintained by Alexei Gerulaitis.

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