@doccolinni wrote:
The problem with transcoding from MP2 to OGG is that the power consumption drastically increases. Here is a good paper on the subject. As you can see on the third page the energy consumption of OGG is approximately 40% greater than energy consumption of MP2.
You can’t actually make conclusions like this because the power consumption depends on the individual codecs used and how they’re optimized for an individual player. You need to look up which codecs they used and how they optimized them and then take that into account. Of course you can’t do that because that paper is stupid and doesn’t say what they compared. So their results are useless.
Even ignoring that, they’re really weird numbers. MPC and MP2 are very similar computationally (MPC is actually derived from MP2), but they claim its much slower? Obviously one of their codecs wasn’t well optimized. MP1 and MP2 are also much faster then MP3 (you can skip the IMDCT stage in mp3 which takes about 25% of the decode time), but they only show a small difference. I think these guys just didn’t know what the heck they were doing. Which is probably why it looks like they couldn’t get that paper published.
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If you want actual useful results for various formats on the Fuze, I suggest these from rockbox:
http://www.rockbox.org/wiki/CodecPerformanceComparison#Sansa_Fuze_v1_ARM922T
These are more interesting since theres a lot of CPUs compared, and you can look up the codecs and how they are optimized.
Theres no MP2 results there, but I just tried on my Fuze V1 and I get 26 MHz for a 128k file, almost exactly the same as MPC. As expected, thats a lot faster then MP3/Vorbis/WMA, so you are correct about not wanting to transcode the files. However, since I think the Fuze OF gets the best battery life for either WMA or MP3, that might be your best bet.
