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Comment Re:Basic Statistics (Score 1) 312

Actually, meaningful and readily understood labels are a considered a good thing, and beneficial to those who work in the field they apply to.

They want to do the equivalent of telling the C standards designers and programmers... You need to stop using a function named main() or _start as the entry point to your programmers.

From henceforth.... main() should be renamed to Program()

Also, instead of returning an INT, it should return a string with text describing the exit condition, or NULL if the program exits with no error.

Also, the order of the arguments should be reversed, and instead of the entry point using an array of pointers to char*, it will be a pointer to an array with 256 elements, and instead of an integer argCount, argCount will be an array with the lengths of each element; the last program parameter will have length of zero, the new signature of the renamed main() function will be:

extern char * Program( char (*argumentData)[256] , int argumentLength[256]);

Comment Re:So you want to retire a statistical term... (Score 5, Informative) 312

the mean *absolute* deviation, rather than the square root of the mean *squared* deviation (the standard deviation).

The mean absolute deviation is a simpler measure of variability. However....

The algebraic manipulation of the standard deviation is simpler; the absolute deviation is more difficult to deal with.

Further, when drawing a number of samples from a large population --- the standard deviation of their mean deviations is substantially higher than the standard deviations of their individual standard deviations; that is to say, the standard deviation of a sample provides an estimate that is more in-line with the whole.

That is to say.... there are cases where the Standard Deviation may be better, AND, much of statistics is using standard deviation as its basis.

Fisher, R. 1920 Monthly Notes of the Royal Astronomical Society, 80, 758-770:

the quality of any statistic could be judged in terms of three characteristics. The statistic, and the population parameter that it represents, should be consistent , The statistic should be sufficient, and the statistic should be efficient -- e.g. the smallest probable error as an estimate of the population. Both the standard deviation and mean deviation met the first two criteria (to the same extent); however, in meeting the third criterion -- the standard deviation proves superior.

Comment Re:The solution (Score 1) 187

The whole solution is to slash the NSA budget and let them figure out where to get the most bang for their buck. They'll never tell you the truth about what they're up to and the "secret" courts are a joke. Cut their budget in half and they may have to choose between spying on their citizens and spying on foreign nationals.

Have you investigated things like "Pentagon audit" or "Black budget"?

  NSA operates under the jurisdiction of the Department of Defense and reports to the Director of National Intelligence.

Congress will not ever touch "defense" appropriations, and were they to do so the DoD "dark matter" will just funnel here. If the agency PR is so very bad, then the real functions function will just move to different sponsorship, under DISA or something.

You have no Republic.

Comment Re: UMS (Score 1) 420

I never said it required a higher bitrate

You literally said:

higher resolution requires a higher bitrate

do you know of anybody that builds their media library to have their 1080p files be lower quality than their 720p?

I do not know anybody who does this intentionally, but most people I know do not encode their own videos. If they get their videos from many different sources that have different standards of quality, it is likely that they will have some videos that are both higher resolution and lower bitrate than other videos in their collection.

Furthermore, you are assuming that all these files are encoded with the same compression algorithm. Some compression algorithms have better performance. It is very possible for a 1080p video that is encoded with an efficient algorithm (e.g. h264) to be both better quality and lower bitrate than that same video encoded at 720p with a lower performing algorithm (e.g. cinepak)

The point is that the the ability to stream a video is directly dependent on the bitrate of the video. The fact that higher resolution videos tend to have a higher bitrate is just a correlation.


I do encode my own videos (well my colleagues videos), professionally. they are watched by literally millions of people literally every day. I aim for a constant quality, not a constant bitrate. Most items I encode at a given subjective quality will add about 50% to encode at 1440x1080 25i over 576x768 25i, however I've encoded some low light stuff in SD that's hit a peak bitrate of 45mbit for a given quality on a given h264 video stream. The 3 minute piece came in at an average 25mbit.

That was originally off a DV25 piece.

Recently, 5 minutes of glorious looking pictures of floods, with a lot of running water, waving reeds, etc; rather than a typical 4-8mbit over 3-4 minutes depending on the clip, this stuff came in at 18mbit. It was well lit, but had a lot of detail and a lot of motion. The piece is a brilliant test, far better than people skipping through a forest.

Now encoding something simple like south park will use a lot less bits for a given quality.

So for the same subjective quality and same resolution you can have a bitrate varying by an order of magnitude at the same resolution. Even if bitrate scaled linearly with resolution you'd still have a minute of some SD material taking more bits to encode than a minute of other HD material.

I haven't run any tests, but my gut would tell me that something cartoonish like southpark at 1080p60 will use a lot fewer bits per second than encoding Blue Planet at 480i or 576i -- for starters I think southpark is only 15fps, so you're only really encoding 1080p15 (given the inter-frame changes on each frame will be zero).

Comment Re: UMS (Score 1) 420

because my router sucks, and with more walls between me and the router, by bandwidth drops severely.

You talking about a video router? Blackmagiv do perfectly serviceable ones for about £1500 that do 3G let alone 1080i.

That's the only place i can see resolution being an issue for routers.

Now if you're complaining about latency, jitter and bandwidth in an file based up world, then you'll be looking at the video bandwidth being the issue, as file system and client buffeting will cope with pretty much any amount of jitter.

Comment Re: UMS (Score 2) 420

That's funny. As long as my network conditions are good I've never had a problem like this with SMB, and I've had a setup for years.

SMB used to (not sure if it still does) have issues with high latency. I think you could only get something like 256kbit per round trip time, so a 10ms latency would limit you to 25mbit.

I assume that it's been fixed now.

Comment Re: UMS (Score 2) 420

SMB streams 1080P stuff fine across my network, as long as I'm close to the router. 720P is damn good anywhere in the house. Been doing it for a long time, most lately on my Nexus 7 and my GBox MX2.

Why would the resolution make any difference to how well it streams? A 2mbit 1080p stream will work fine, a 270mbit 576i stream wont

Comment Re:Routing around bad neighborhoods? Want! (Score 1) 162

when i was in south africa, i was told that in central johannesburg people sometimes get robbed of their cars. stop at the red light, two cars come. one stops in front of you, one behind you, a couple of guys with guns throw you out of your car.
"traffic accidents" would not be enough :)

If you're lucky. A guy in our building in Joburg was carjacked at the lights, but the guy fired the pistol having failed to remove the keys.

Fortunatly it jammed, and the would-be jacker took his time clearing the gun why the chap escaped. When Group 4 arrived 10 minutes later they found both the misfired bullet with a dent in the back, a few spent casings, and a bullet hole in the back of the car.

Lucky escape, I'd rather drive in gaza than joburg.

Comment Re:Winamp is still the best player around! (Score 1) 188

Don't forget,

-global hotkey support
-small form factor
-visualization plugins
-crossfading plugins
-instanced playback to multiple soundcards
-built in web server control
-winamp lite installer filesize is 4134 kb and currently consumes 32mb of ram on my system
-lcd display plugins
-LIRC plugin
-streamripper plugins
-flawless manual and automated operation, virtually crash free

And those are just the features I have used in the past week! for free!

Nothing comes close. Winamp IS audio on windows.

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