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Comment We're fixing this (Score 4, Informative) 333

Firefox OS is trying to fix much of this.
https://wiki.mozilla.org/Firef...
https://developer.mozilla.org/...
The Web is the most successful platform of all time and we're leading the pack on bringing a the Web platform to mobile in a way that's integrated rather than fractured like the existing app store models.

Comment Re:Faster is not necessarily better: Quality matte (Score 5, Informative) 101

This is false. Decoding for modern video formats is strictly defined, and all decoders must produce bit-perfect output. You can add as many filters as you want after that, but that's a postprocessing step in the video player and has nothing to do with the decoder. Things like in-loop filters are strictly defined as part of the decoding process and must be there for the decoder to be considered correct.

Comment Re:Why does Wikimedia hate batteries? (Score 1) 235

Nope, they just crash, lag, or play it with severe artifacts (the latter happens with some hardware codecs and 10bit files).

Basically no modern video codecs are designed to gracefully degrade given limited decoder features, because they rely on bit-perfect output to be used as a reference for future frames. Any error accumulates in the decoding loop and becomes significant artifacting until the next I frame.

Submission + - Ask Slashdot: What's there to like about the BETA? (slashdot.org) 7

Narnie writes: I come to /. not for the nearly interesting pseudo-tech articles, but for the lively, self-moderated discussion. Today I'm bit surprised to see every discussion summarized to fuckbeta. Popping up all over the place there's discussions about beta and even alternatives being revived and created. As I tend not to RTFA, I haven't sampled the beta myself. So, I ask you guys, what's there to like about the BETA and what's there to loath?

Submission + - beta is shit 2

An anonymous reader writes: beta is shit

Comment It's just 1200baud 7O1 Bell 202 (Score 5, Informative) 163

0x80 is just a null byte with odd parity. What she apparently missed is that this is bog-standard Bell 202 AFSK (1200 baud) with 7 data bits and odd parity, and the data is ASCII. By throwing away the top nybble, she was throwing away the parity bit and the top 3 bits of the ASCII encoding of decimal digits. The fact that it was a parity bit should've been pretty obvious, since the top nybble flips between 0x3x and 0xbx in the pattern that you'd expect for a parity bit.

You can decode it with off the shelf software, throw away the top bit, and get back mostly ASCII:

$ ./minimodem --rx 1200 -f ~/helicopter.wav | tr '\200-\377\r' '\000-\177\n'
### CARRIER 1200 @ 1200.0 Hz ###
  282 0002.3
#L N390374 W09432938YJ
#AL #NA 282 0002.3
#L N390374 W09432938YJ
#AL #NA 283 0002.3
#L N390372 W09432928YJ
#AL #NA 283 0002.3
#L N390370 W09432918YJ
#AL #NA 283 0002.3
#L N390370 W09432918YJ
#AL #NA 283 0002.3
[...]

I'm actually surprised that she missed / didn't mention this, considering her experience with signals analysis and demodulation. This is pretty much as basic as telemetry data modulation gets! Then again, as a reverse engineer myself, sometimes we get caught up doing deep analysis of something that later turns out to be totally trivial :)

Comment Re:Metadata (Score 1) 256

Metadata is just data about data. This can be almost anything. For voice recordings, you could reasonably claim the following information to be metadata:
- Existence of keywords or keyphrases
- Voice signatures, identifying the speakers
- Stress levels of the voices

If you look at how US agencies are gaming the legal system, they will probably claim that transcripts of conversations are not the conversations themselves and therefore metadata.

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