How DRM Affects Battery Life

With all the furor over DRM lately, CNet asked itself the simple question, “How does DRM affect battery life on your iPod?” As you might expect, the answer is — badly.

CNet has looked at numerous mp3 players, including the iPod, the Zen Vision and Sony’s new Sony Walkmans, first establishing their peak battery life when playing unprotected MP3s and then comparing them to battery life when playing nothing but DRM-protected formats like AAC or WMA. The results are extremely discouraging: for example, on the Creative Zen Vision, you lose 25% of your battery life when playing WMAs over unprotected MP3s… and that’s without putting the backlight on.

Granted, there’s a lot of other things that will drain your mp3 player faster: playing higher bitrate files, using the backlight, watching videos or even using more powerful headphones. That extra processing power and therefore more juice are required to decode protected files isn’t terribly surprising. Still, it’s another bullet point on why the industry’s push towards DRM sucks for consumers.

MP3 Insider: The truth about your battery life [CNet]


Edit Your Comment

  1. SamC says:

    Comparing protected WMAs to unprotected MP3s is comparing apples to oranges.

    It is well known that different file types need different amounts of processor time to be decoded and played.

    Someone should be comparing protected WMAs to unprotected WMAs or, in the case of the ipod, protected AAC files to unprotected ones.

    I used to have a rio karma. It got about 16 hours of battery when I played only mp3s. When I played ogg vorbis files, I got around 12. I could get more ogg files onto the karma (they were about a third smaller), but I paid the price in battery life for the extra compression.

  2. Papercutninja says:

    I thought the tests were only done on PlaysForSure WMAs…there was no mention of AACs…or am i just dyslexic today? I’m very curious as to how DRM affects my iPod…

  3. Fairytale of Los Angeles says:

    Sam mentioned this in passing, but I think it bears repeating: AAC is not, in and of itself, a protected format. It’s short for “Advanced Audio Coding,” which is part of the MPEG-4 audio and video standards.

    MPEG-4 allows you to pair standard formats with external DRM systems; this is what Apple has chosen to do with iTunes Music Store files. The “protected AAC” format is simply regular AAC paired with Apple’s own FairPlay DRM technology.

  4. SamC says:

    Well… looks like this made it onto slashdot:

    Hopefully someone will run a good test that can see useful results with.

    Actually, one wouldn’t even need to use an ipod to run the tests. Just run the same song at various bitrates and filetypes, with DRM and without from a single player program, and monitor CPU & memory usage. More CPU/memory = more electricity being used = shorter battery life.