What is the most battery-sucking LOSSY codec?

[Marvin the Martian]

From what I understand, MP3 is the easiest for devices to decode. Then you have AAC, Vorbis, and WMA which supposedly can deliver better SQ at low bitrates(step back ABX Nazis....this isn't about which sounds best) but apparently are harder to decode....so which is the most battery-intensive to decode?

[ZenChick]

Hmmmmm.... How to Godwin a thread in the first post...

Anyway, back on topic: In my experience, WMA significantly reduces the battery life in many players, so I would chalk this up as the hardest to decode.

[dfkt]

APE high profile should be among the least efficient ones. One of the many reasons why FLAC is better.

I bet Saratoga could contribute a lot to this topic.

EDIT: I think the topic title didn't say LOSSY large enough for me to comprehend its meaning.

[saratoga]

Originally Posted by Marvin the Martian

From what I understand, MP3 is the easiest for devices to decode.

I don't agree with that. IMO MP3 is probably a bit harder to decode the WMA, AAC or Vorbis. The decode process for MP3 is actually quite complicated with a lot of stupid, needless crap that wastes CPU time. Optimizing it is not much fun compared to simpler formats.

Originally Posted by Marvin the Martian

so which is the most battery-intensive to decode?

Probably AAC-HE (or its DOA brother AAC-Main). Its so bad the spec actually defines a "low accuracy" mode that incompletely decodes the files in order to get CPU load down to something that a normal AAC-LC device could handle. Its downright nasty.

You have to decode a normal AAC file, then do a sort of subband decomposition on your own decoded file, mirror the bands to higher frequencies, and then recompose the subbands. Its something like like decoding an AAC file, then encoding an mp3, and finally decoding the mp3 and adding it back to the AAC.

In second place would probably be ATRAC3. Its very much like MP3 except worse.

Interestingly, all three of these codecs are MDCT based transform codecs that have found a way to incorporate a QMF or PQF filterbank, thus allowing them to waste large amounts of CPU time. All of the fast ones you mention are pure MDCT codecs.

[saratoga]

The fastest two codecs I've optimized are probably WMA standard and Cook. They're very similar, and very simple. Basically the absolute minimum needed to efficiently encode audio with very little added junk.

[Marvin the Martian]

Originally Posted by saratoga

The fastest two codecs I've optimized are probably WMA standard and Cook. They're very similar, and very simple. Basically the absolute minimum needed to efficiently encode audio with very little added junk.

Would it be fair to assume this could vary between different manufacturers as well, with their different firmware implementations?

[Marvin the Martian]

Originally Posted by ZenChick

Hmmmmm.... How to Godwin a thread in the first post...

It worked though, didn't it?

Originally Posted by dfkt

APE high profile should be among the least efficient ones. One of the many reasons why FLAC is better.

Well, we are in agreement on our lossless codec of choice.

Originally Posted by dfkt

I bet Saratoga could contribute a lot to this topic.

I also suspected that he would have some answers, and it seems that he does.

Originally Posted by dfkt

EDIT: I think the topic title didn't say LOSSY large enough for me to comprehend its meaning.

Fixed!

[saratoga]

Originally Posted by Marvin the Martian

Would it be fair to assume this could vary between different manufacturers as well, with their different firmware implementations?

Implementation matters a lot. You can always make an efficient format slow.

A good example is the Fuze, where battery life is halved if you use FLAC, even though FLAC is probably one of the fastest formats ever in widespread use. I estimated that the Sandisk firmware takes about 60 MHz to decode a file, while Rockbox on the same player uses about 15 MHz. The decoder they use is just really, really bad.

I suspect MP3 will always be one of the fastest formats on mostplayers (except maybe on some Sony players that do ATRAC) since thats what everyone uses when they calculate battery life.

[JK98]

Is mp3 the most power efficient, or are there more power efficient formats? Years ago storage was expensive and in short supply. Now battery life is often the limiting factor.

[saratoga]

Originally Posted by JK98

Is mp3 the most power efficient, or are there more power efficient formats? Years ago storage was expensive and in short supply. Now battery life is often the limiting factor.

Scroll up.

[Marvin the Martian]

Originally Posted by JK98

Is mp3 the most power efficient, or are there more power efficient formats? Years ago storage was expensive and in short supply. Now battery life is often the limiting factor.

Originally Posted by saratoga

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