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mejohnsn (22) [Avatar] Offline
#1
I have been going over both the API demos and Ch. 10 of UA 1st edition. While I am grateful for the coverage of the basics I find in UA, I can think of a couple other Media related issues coverage for which would have made the chapter much more informative for me.

1) UA edition one says, "G1 supports only MP4 and 3GP". But MP4 is a file-format, while 3GP is not; 3GPP is the file format. Nor is specifying file format enough.

For clearly from the video examples I tried, not every file whose FORMAT is MP4 is supported: it depends on what is IN the container, too. In particular, at this point, it is my BELIEF that the H.263 video codec is better supported on the phones than H.264. But I could be wrong.

BTW: the test.mp4 file in ch10 download does not render very well: http://www.yo-yo.org/mp4/yu.mp4 renders much better (but only on the phone: it does not render at all on the emulator).

1a) my own limited experience confirms what I find in other online forums: the above case is common, a file that fails to render video under the emulator might render video just fine on a phone. Hence many people skip the emulator and test video on the phones.

2) Even once we have the right codec, the phones can still be picky about encoding parameters. One post claimed that "Downsampling our h.264 videos from 640x480 to 320x240 made the videos work in all the Android devices we tested."

So please cover what time and spatial sampling rates are well tolerated by how wide a range of phones. I realize doing the entire range is asking a lot; but even a little more (than in UA 1st ed) coverage of the topic will be very helpful, even if you have to refer the reader elsewhere for more details.

3) If you give a website with handy streaming MP4 files to test Android's streaming playback, the webmaster would probably not be pleased at the surge of traffic: but could you add some hints at how to find such files? Surely it is non-optimum to expect people to cross two hurdles at once, and learn to host their own streaming video files on their own server at the same time they are trying to learn how to run the streaming client. Yet that is what some online tutorials dosmilie

I found the above yo-yo video with Google, but already forgot the magic words for the querysmilie

So I am thinking of providing not a single website, but a suggested Google query to find streaming MP4 samples.