[General Topics] Menneisyys:
As can clearly be seen, while there indeed isn't any kind of buffering, the overall lower CPU usage of the H.263 / MP3 decoder has resulted in about the same average power consumption as that of MobiTubia.

All in all, as a rule of thumb: on Symbian:

- when you watch YouTube videos over Wi-Fi and would like to have as long battery life as possible, prefer MobiTubia

- when over 3G, both will behave almost the same way.

2. (Windows Mobile): I've continued comparing milesmowbray's youtubeplay to CorePlayer 1.2.4.

a. in youtubeplay, you can fetch the first 50 hits of any search / "Related" operation; but, it seems, no more (it, then, complains about the network's not working.) To set this, go to Config (button in the bottom left) and just increase the number of hits shown with the second slider (Results returned).

b. on the test iPAQ 210, youtubeplay uses about 62-64% CPU time to decode and play back (FLV) videos (in both Portrait and Landscape). CorePlayer, at the same time, uses about 21...23% (again, in FLV). With H.264, of course, CorePlayer requires far more CPU time (more than 80%) and if you run other even slightly CPU-intensive tasks (like acbTaskMan to track CPU usage), there will be some (about 10...30%) dropped frames, particularly with really dynamic videos like those of Call of Duty 2.

This means if you plan to stick to the FLV format (because you're on a QVGA device and, therefore, you couldn't take advantage of the higher resolution of the H.264 video or you're on VGA but the source video is already of bad quality making it unnecessary to stream in H.264), you can save a lot of battery if you go for CorePlayer on CPU architectures that have much higher power consumption with high CPU loads than with low ones. Typically, Intel / Marvel Xscale CPU's belong to this group, where the difference in battery life can even be 1.5...2-fold between two players using 22% and 63% CPU cycles. Of course, with activated Wi-Fi and higher levels of backlight, the difference won't be this pronounced. The only architecture that (somewhat strangely) doesn't exhibit excess power consumption with higher CPU loads is that of Samsung (at least the older architectures; I haven't tested the latest, 6400-series in this respect.)

What about buffering, you may ask. Do alternative solutions like milesmowbray's youtubeplay have an advantage over CorePlayer in the same way as was certainly visible on Symbian? The answer is, unfortunately, no. Just look at the following screenshot, taken via Wi-Fi without power saving enabled on the Dell Axim x51v running WM6.1. (Note that, while CorePlayer had absolutely no problems playing back clips without dropped frames on this particular model, youtubeplay fared much worse. That is, using youtubeplay is in no way recommended on the x51v.)

The CPU usage is shown in the upper and the power consumption on the lower pane. The first ~8 minutes show CorePlayer playing the clip; after that (there's a small discontinuation in the chart) youtubeplay follows. As can clearly be seen, the average power consumption of youtubeplay is much higher than that of CorePlayer. Raising the buffer size from 2048 kbytes to, say, 16Mbytes (to allow for the complete buffering of most clips) won't help at all.

With Wi-Fi power saving enabled, the power consumption is far lower - but, with youtubeplay, it's still definitely larger than with CorePlayer:

All in all, unlike on Symbian, on Windows Mobile you'll always want to stick to CorePlayer in order to absolutely minimize power usage when playing back FLV YouTube videos. (Again, the above power usage tests only only show FLV playback power usage as it's FLV playback that the other players support, not H.264.)