Ha... however considered that.flv video is H263 (or is it H264 now?) I guess you could find a program that would change the container to an AVI-compatible one and thus avoid recompressing?
The original Flash video format is Sorenson Spark. It's based on H.263, but incompatible.
H.264 and AAC don't fit in an AVI well at all... It's possible to do, but it's a mess, which most apps don't properly support.
In either case, I don't believe for a second that YouTube's video conversion is smart enough to detect compatible video or audio encodings in a different container, and remux rather than reencode.
Despite what the parent said, however, you can encode properly formatted, fully compatible FLVs to youTube, and they will be published, unmodified.
Can you even make a transmitter + power supply that small that would still be powerful enough to communicate with the ground?
When you have a 2+ meter dish with high-gain LNBF properly aimed, you can pick-up a radio signal from a wrist watch...
Or are you just supposed to send up 20 grams of foil or something that can be tracked with ground radar?
It wouldn't be a bad idea to send up something like a concave sheet of metal (aimed towards the planet) to use as a simple signal reflector. I'm sure hams and DXers would love the idea. It would be a lot easier and more consistent than bouncing signals off the moon.
It would be a very interesting world if we had a significant number of those in orbit. From the comfort of your living room, you could listen-in to any radio signals, being broadcast anywhere in the entire world, provided only that you have equipment that is sensitive enough to pick the weak incidentally reflected signal you want, out of the background noise.
Starch, in small bulk quantities that are readily available at your local supermarket, is available at no more than 5 cents per ounce, even in today's dollars.
I'd like to find out where you shop... I pay just under 11 cents per ounce of rice, and that's the cheapest stuff, at the cheapest supermarket around. It may be cheaper in bulk (Costco, Sam's Club), but I don't imagine it's less than half price.
Now, every other food in America is made from grain, or it's another vegetable, which you could easily grow yourself.
You can grow lots of things, but it damn sure isn't free to do so. There's substantial cost in water, fertilizer, pesticide, etc. Not to mention acquiring enough land to feed a family! A small yard isn't going to cover it.
i want you to eat nothing but beans and rice for a month and let me know how you feel about it. i'm betting you couldn't even last a week.
Hell, that's a normal week in college.
I'm not the OP, but I easily made it through several months eating similarly.
And there's a lot more similarly cheap foods available: ramen fried noodles, (dried) potatos, oatmeal, corn flakes, powdered eggs, canned chilli, macaroni & cheese, spaghetti, peanut butter, bread, etc. You can even get dried butter, cheese, etc. You probably want to throw in some sugar, salt, and drink flavoring to fight the blandness, but it's easily do-able.
I'm sure there's a lot more cheap food available as well, which should give an large enough variety for anyone.
You don't even need a checksum - just a straight comparison will do (and will avoid hash collisions as well).
If comparing multiple copies to the original, a diff will be MUCH slower, however. The odds of an accidental collision are awfully slim, even with the simplest hash.
The guys working at these places are probably just trying to get by in this world - they have nothing to do with Apple's corporate decisions.
That's a BS excuse, which is used all too often.
Lawyers working for the RIAA/MPAA are just trying to pay their mortgages as well. That doesn't make them innocent bystanders. Ditto for lobbyists for the tobacco industry, oil companies, etc., etc.
First, they're guilty in some small part, because they get paid by the company. Having an unimportant job doesn't clear you of all personal responsibility.
Secondly, you can't very well talk to those who are responsible. Those company employees are the only proxy you get, so it's them, or nothing.
Third, bothering enough underlings will start to hurt the bottom line, and get the attention of the higher ups.
I generally dislike the FSF, but will reserve judgment on their actions and intentions here. But the rationale commonly being given here for why this is a bad idea are stupid and nonsensical.
It seems like it would be hard to enforce jurisdiction in space
The law doesn't apply to space. The law applies to you, on the ground, before you send anything up there.
If you have a space craft that is unable to take photos (so it doesn't fall under this law), but then, in space, it is upgraded to include that capability, THEN you'd have a case for jurisdictional exclusion. When you want to launch a craft, from the US, that can take pictures from the get-go, then you're violating this law.
The flip side of this would be the "sex tourism" laws, that make it illegal to leave the country with an intent to have sex with under-aged kids in other countries, where such things are perfectly legal. Presumably, the law wouldn't apply if you went for a vacation, and just decided, while you were there, to solicit the services of an under-aged hooker.
The FCC mandated that the HD video be encoded in Mpeg2 only; never planning ahead using Moore's law and allowing different formats, such as Mpeg4!
How was the FCC supposed to plan to use formats that didn't yet exist? Mandate the decoder equipment include an infinitely fast processor, and continually transmit firmware updates for every box, everywhere?
Had they allowed Mpeg4, several HD channels could have been fit into the 19Mb/s channel bandwidth, along with other SD channels as well.
Several HD channels CAN fit into the 19Mbit/s channels using MPEG-2. And H.264/AVC isn't nearly so astonishing as you make it out to be. The most liberal comparisons place H.264 at just about 2X better than MPEG-2, and you wouldn't get all of that at HDTV bitrates.
Plus, the computational power needed for H.264 decoding would drastically drive up the cost of HDTV tuners and converter boxes.
And finally, I'd like to point out that newer technologies are always, inherently, over-rated. You are comparing MPEG-2 encoder chips first made over a decade ago, with H.264 encoders made... yesterday. Many improvements to MPEG-2 are possible, without losing backwards compatibility, that put it much closer to H.264.
In addition, high bitrates are MPEG-2's strong suit. H.264 doesn't promise remotely as dramatic improvements there, to begin with, having been designed and targeted at low-bitrate applications like cell-phones. The features that make a very low-bitrate picture watchable simply don't translate into the highest possible quality picture at high bitrates. You can see the same thing with HE-AACv2, which is superb at terribly low rates, but less than useless at bitrates above 64kbit/s per channel.
So, digital isn't necessarily infallible, because ultimately everything in real life is analog. It just has a much higher tolerance for error before even the slightest degradation occurs.
Digital is "infallible" by definition. The media it's stored on, may not be.
In either case, looking for imperfections in digital data in the analog domain is pretty stupid. A simple checksum will instantly determine if there is ANY variation from 100% perfection, and most software has such error checks built-in. Why yours does not, I can't guess.
there is no case where the world's best female athlete can beat the world's best male athlete at any physical sport.
There are a few cases where this rule does not hold true. The lower body weight of women can make-up for lesser sheer physical strength, and in endurance sports, that can eliminate the advantage. Certainly, the best female marathon runners are challenging, though haven't yet exceeded all of, the best male marathoners.
one seriously doubted that males and females learn mathematics with similar aptitude in any case,
WTF? Are you 12, and too young to remember blatant institutional sexism?
Until innumerable studies such as this were launched, there was indeed a long-standing, and strongly-held belief that males were inherently more apt at mathematics and the sciences, while women were more apt at more artsy and menial endeavors like housework.
Back when I was in 5th grade, there were 2-3 girls in my computer class that were much better programmers than I. Much better.
Fast forward to today. They're housewives. I'm a Software Engineer. It's sad and disheartening. I wish there were more women in my field.
It's like puberty fried their brains completely. If it weren't for that I could easily envision them being much better at what I do than I am.
Have you considered the opposite possibility? That puberty didn't make the females any worse programmers, but that around puberty the males (ie. you) started improving their skills more dramatically?
Such is very widely known to be the case with physical abilities (testosterone is powerful stuff), and I could certainly envision some specific mental functions (perhaps mathematics) following the same path. Certainly, it is known that girls do better much at the start of elementary school, so it wouldn't be unprecedented to show such a difference. If that is in fact the case, tests at the end of high school may be too early to demonstrate the disparity. Tests of men and women in their 30s would better show any post-pubescent trends much more clearly, but except for post-grads, there's no common path that both men and women would have followed to be inherently on equal footing for such tests to be meaningful.
What I've also seen is the standard deviation for boys is greater. Boys are usually at the bottom, the middle and the top with the girls usually clustered in the center. Admittedly, my sample sizes are small and I'm looking at a self-selected group.
Your observations are, in fact, consistent with significantly larger studies on the subject. Specifically, you might want to start by reading the transcript of "Is There Anything Good About Men?" by Roy F. Baumeister. http://www.psy.fsu.edu/~baumeistertice/goodaboutmen.htm
Diesel engines are more efficient than internal combustion engines. End of story. They use drastically higher compression ratios, and their design inherently allows them to do so at arbitrarily high ratios (with any fuel) without any risk of detonation (backfiring). That (about 3X) higher compression ratio means that whatever fuel you put in it has a higher percentage of it's energy turned into useful work, rather than waste heat, and diesels do indeed run cooler because of it..
Less than 6 months ago, there was a story that either GM or Ford (I don't recall which) was designing an engine that gets 30% better fuel efficiency. Their secret? Use a diesel engine, tuned to instead burn gasoline...
Reverse for ethanol, where a gallon has only 75% of the energy of a gallon of gasoline.
Ethanol also has a dramatically higher octane rating, however. That allows for significantly higher compression in an internal combustion engine. Adjusting for that, you can still actually get better fuel efficiency with ethanol than gasoline.
What the fuck does threading have to do with video quality?
Video encoding is highly inter-dependent, and is not given to parallel processing. You can't split it across cores without making certain assumptions, and skipping (or performing out of order) certain calculations, which will reduce the quality/efficiency (at a give bitrate).
Video encoders chop up frames into slices anyway for different reasons (different slice characteristics, concealment for transmission errors). Full-frame slices were common for MPEG-1 but modern codecs almost invariably use sliced frames now.
Simply not true. Some may, but most certainly do not. I can tell you for a fact that x264 does not, neither do any of the ffmpeg encoders.
There's nothing inherently 'inefficient' about it, as fixed GOP *size* does not imply fixed-GOP *structure*.
Fixed GOP size requires you to place an I-frame at a specific interval. That I-frame placement will invariably NOT fall on a scene change, therefore wasting a substantial number of bits. And no, most encoders do not use a fixed GOP size (just a maximum, and sometimes also a minimum).
Even then, with 2-pass encoding (which you want anyway if you're concerned about quality) you already figured out the video characteristics after the 1st pass, including GOP structure, so parallelization on the GOP level is still an option.
Yes, that's true. You can get a speed-up, but solely on the second-pass.
Luma and chroma-U/chroma-V are independent, so you can process them in parallel. Modern codecs can even use different motion vectors for luma/chroma, so with these you can even parallelize motion estimation.
I wasn't talking about parallelizing quantization (which is cheap anyway) or DCT.
Well then, I'm still waiting to hear exactly what operations you think can be parallelized.
As for the 'little bit of knowledge': I've written my own MPEG-1 parallel decoder for the PS3 so I guess I know what I'm talking about.
A DECODER is vastly different from an ENCODER. A decoder has very few iterative processes that can't be parallelized well, while an encoder has a very large number.
Or just convert 2 videos at once, or 4 for a quad core etc. They did suggest they have lots to convert, and it's a pretty easy way to get all available cores working hard.
More to the point, multi-threading introduces overhead, and quality loss in the encoded video. So, if you do have at least as many videos as you have cores, encoding each, single-threaded, on it's own core, will be slightly faster, and slightly higher quality than encoding those same videos sequentially, using a codec with multi-threading.
Actually, the MPEG stream resets itself every n frames or so (n is often a number like 8, but can vary depending on the video content).
"Or so" and "can vary" being the key points.
Until the encoder processes the entire video, and decides where it is most appropriate to place "keyframes" (I-frames), you can't parallelize anything. The same goes for rate-control (unless you're strictly CBR, which is similarly terribly wasteful).
This is why x264 performs it's first pass almost entirely on a single core (perhaps throwing 20% of the work onto a second core), and only on the second pass is it fully multi-threaded.
You could of course split each frame in slices, and process these in parallel.
That is commonly how it's done, but you do lose some bitrate efficiency that way, and it doesn't parallelize perfectly as many operations need to be performed across the whole frame after the slices are reassembled, before the next frame/slices can be processed. x264 did this, but (somewhat recently) dumped this method for something better.
Or skip the video N frames between each core, with N being the number of frames between MPEG keyframes.
No (remotely decent) MPEG encoder made in the past 2 decades uses a fixed GOP-size. That's horribly inefficient.
Or have core 1 do the luma and core 2 and 3 the chroma channels.
Do *WHAT* to the luma and chroma channels?
Or pipeline the whole thing and have core 1 do the DCT, core 2 the dequant etc.
That sounds like a core relay race... each one sitting idle most of the time, as it waits for data from the previous. It doesn't matter how fast you can do DCT and quantization, since the (slow) motion estimation, scene-change detection, and rate control first need to process the frame to decide how to change what happens to the next frame.
Parallel quantization is useless, because quant levels are different for each frame due to bitrate constraints and frame complexity. Parallel DCT is useless, since you need to know whether it's going to be an I, P, or B frame, and the differential from the previous frame, to do anything. etc.
Plenty of ways to parallelize decoding, and even more for encoding...
A little bit of knowledge is a dangerous thing... You've mostly come up with lots of ways to keep the CPUs maxed-out, doing busy work that can't help speed-up encoding at all.
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Sounds like a Win-Win scenario!
The original Flash video format is Sorenson Spark. It's based on H.263, but incompatible.
H.264 and AAC don't fit in an AVI well at all... It's possible to do, but it's a mess, which most apps don't properly support.
In either case, I don't believe for a second that YouTube's video conversion is smart enough to detect compatible video or audio encodings in a different container, and remux rather than reencode.
Despite what the parent said, however, you can encode properly formatted, fully compatible FLVs to youTube, and they will be published, unmodified.
Youtube has accepted flvs for quite some time now. That does not excend to SWFs, however. Animations are not videos, and can't be converted easily.
The grandparent was perhaps not a troll, but it certainly was an extremely off-topic rant, and it's more than appropriate that it get modded down.
The parent was just complaining about moderation, which is almost always off-topic, and is generally modded as such.
Your post, too, is just a pointless complaint about one random bit of moderation that has no real significance.
When you have a 2+ meter dish with high-gain LNBF properly aimed, you can pick-up a radio signal from a wrist watch...
It wouldn't be a bad idea to send up something like a concave sheet of metal (aimed towards the planet) to use as a simple signal reflector. I'm sure hams and DXers would love the idea. It would be a lot easier and more consistent than bouncing signals off the moon.
It would be a very interesting world if we had a significant number of those in orbit. From the comfort of your living room, you could listen-in to any radio signals, being broadcast anywhere in the entire world, provided only that you have equipment that is sensitive enough to pick the weak incidentally reflected signal you want, out of the background noise.
I'd like to find out where you shop... I pay just under 11 cents per ounce of rice, and that's the cheapest stuff, at the cheapest supermarket around. It may be cheaper in bulk (Costco, Sam's Club), but I don't imagine it's less than half price.
You can grow lots of things, but it damn sure isn't free to do so. There's substantial cost in water, fertilizer, pesticide, etc. Not to mention acquiring enough land to feed a family! A small yard isn't going to cover it.
Hell, that's a normal week in college.
I'm not the OP, but I easily made it through several months eating similarly.
And there's a lot more similarly cheap foods available: ramen fried noodles, (dried) potatos, oatmeal, corn flakes, powdered eggs, canned chilli, macaroni & cheese, spaghetti, peanut butter, bread, etc. You can even get dried butter, cheese, etc. You probably want to throw in some sugar, salt, and drink flavoring to fight the blandness, but it's easily do-able.
I'm sure there's a lot more cheap food available as well, which should give an large enough variety for anyone.
Master CDs don't just create themselves...
If comparing multiple copies to the original, a diff will be MUCH slower, however. The odds of an accidental collision are awfully slim, even with the simplest hash.
No, I'm certainly not. I'm merely challenging the statement: "Denial of Service attacks (of any kind) should not be perpetrated by honorable people."
That's a BS excuse, which is used all too often.
Lawyers working for the RIAA/MPAA are just trying to pay their mortgages as well. That doesn't make them innocent bystanders. Ditto for lobbyists for the tobacco industry, oil companies, etc., etc.
First, they're guilty in some small part, because they get paid by the company. Having an unimportant job doesn't clear you of all personal responsibility.
Secondly, you can't very well talk to those who are responsible. Those company employees are the only proxy you get, so it's them, or nothing.
Third, bothering enough underlings will start to hurt the bottom line, and get the attention of the higher ups.
I generally dislike the FSF, but will reserve judgment on their actions and intentions here. But the rationale commonly being given here for why this is a bad idea are stupid and nonsensical.
The law doesn't apply to space. The law applies to you, on the ground, before you send anything up there.
If you have a space craft that is unable to take photos (so it doesn't fall under this law), but then, in space, it is upgraded to include that capability, THEN you'd have a case for jurisdictional exclusion. When you want to launch a craft, from the US, that can take pictures from the get-go, then you're violating this law.
The flip side of this would be the "sex tourism" laws, that make it illegal to leave the country with an intent to have sex with under-aged kids in other countries, where such things are perfectly legal. Presumably, the law wouldn't apply if you went for a vacation, and just decided, while you were there, to solicit the services of an under-aged hooker.
Missed out on the Civil Rights movement, did we?
Didn't study Ghandi and Indian independence in school?
Never heard of Vietnam-era anti-war protests?
How was the FCC supposed to plan to use formats that didn't yet exist? Mandate the decoder equipment include an infinitely fast processor, and continually transmit firmware updates for every box, everywhere?
Several HD channels CAN fit into the 19Mbit/s channels using MPEG-2. And H.264/AVC isn't nearly so astonishing as you make it out to be. The most liberal comparisons place H.264 at just about 2X better than MPEG-2, and you wouldn't get all of that at HDTV bitrates.
Plus, the computational power needed for H.264 decoding would drastically drive up the cost of HDTV tuners and converter boxes.
And finally, I'd like to point out that newer technologies are always, inherently, over-rated. You are comparing MPEG-2 encoder chips first made over a decade ago, with H.264 encoders made... yesterday. Many improvements to MPEG-2 are possible, without losing backwards compatibility, that put it much closer to H.264.
In addition, high bitrates are MPEG-2's strong suit. H.264 doesn't promise remotely as dramatic improvements there, to begin with, having been designed and targeted at low-bitrate applications like cell-phones. The features that make a very low-bitrate picture watchable simply don't translate into the highest possible quality picture at high bitrates. You can see the same thing with HE-AACv2, which is superb at terribly low rates, but less than useless at bitrates above 64kbit/s per channel.
Digital is "infallible" by definition. The media it's stored on, may not be.
In either case, looking for imperfections in digital data in the analog domain is pretty stupid. A simple checksum will instantly determine if there is ANY variation from 100% perfection, and most software has such error checks built-in. Why yours does not, I can't guess.
There are a few cases where this rule does not hold true. The lower body weight of women can make-up for lesser sheer physical strength, and in endurance sports, that can eliminate the advantage. Certainly, the best female marathon runners are challenging, though haven't yet exceeded all of, the best male marathoners.
WTF? Are you 12, and too young to remember blatant institutional sexism?
Until innumerable studies such as this were launched, there was indeed a long-standing, and strongly-held belief that males were inherently more apt at mathematics and the sciences, while women were more apt at more artsy and menial endeavors like housework.
Have you considered the opposite possibility? That puberty didn't make the females any worse programmers, but that around puberty the males (ie. you) started improving their skills more dramatically?
Such is very widely known to be the case with physical abilities (testosterone is powerful stuff), and I could certainly envision some specific mental functions (perhaps mathematics) following the same path. Certainly, it is known that girls do better much at the start of elementary school, so it wouldn't be unprecedented to show such a difference. If that is in fact the case, tests at the end of high school may be too early to demonstrate the disparity. Tests of men and women in their 30s would better show any post-pubescent trends much more clearly, but except for post-grads, there's no common path that both men and women would have followed to be inherently on equal footing for such tests to be meaningful.
Your observations are, in fact, consistent with significantly larger studies on the subject. Specifically, you might want to start by reading the transcript of "Is There Anything Good About Men?" by Roy F. Baumeister. http://www.psy.fsu.edu/~baumeistertice/goodaboutmen.htm
Diesel engines are more efficient than internal combustion engines. End of story. They use drastically higher compression ratios, and their design inherently allows them to do so at arbitrarily high ratios (with any fuel) without any risk of detonation (backfiring). That (about 3X) higher compression ratio means that whatever fuel you put in it has a higher percentage of it's energy turned into useful work, rather than waste heat, and diesels do indeed run cooler because of it..
Less than 6 months ago, there was a story that either GM or Ford (I don't recall which) was designing an engine that gets 30% better fuel efficiency. Their secret? Use a diesel engine, tuned to instead burn gasoline...
Ethanol also has a dramatically higher octane rating, however. That allows for significantly higher compression in an internal combustion engine. Adjusting for that, you can still actually get better fuel efficiency with ethanol than gasoline.
Or you could just as easily say: If we just started assuming every little thing was safe and just started using it, we'd all be dead in no time.
(Not a tin-foil hat type, but I think you're making an ass out of yourself with such nonsensical BS arguments).
Video encoding is highly inter-dependent, and is not given to parallel processing. You can't split it across cores without making certain assumptions, and skipping (or performing out of order) certain calculations, which will reduce the quality/efficiency (at a give bitrate).
For reference: http://www.vassilios-chouliaras.com/pubs/c25.pdf
Simply not true. Some may, but most certainly do not. I can tell you for a fact that x264 does not, neither do any of the ffmpeg encoders.
Fixed GOP size requires you to place an I-frame at a specific interval. That I-frame placement will invariably NOT fall on a scene change, therefore wasting a substantial number of bits. And no, most encoders do not use a fixed GOP size (just a maximum, and sometimes also a minimum).
Yes, that's true. You can get a speed-up, but solely on the second-pass.
Well then, I'm still waiting to hear exactly what operations you think can be parallelized.
A DECODER is vastly different from an ENCODER. A decoder has very few iterative processes that can't be parallelized well, while an encoder has a very large number.
More to the point, multi-threading introduces overhead, and quality loss in the encoded video. So, if you do have at least as many videos as you have cores, encoding each, single-threaded, on it's own core, will be slightly faster, and slightly higher quality than encoding those same videos sequentially, using a codec with multi-threading.
"Or so" and "can vary" being the key points.
Until the encoder processes the entire video, and decides where it is most appropriate to place "keyframes" (I-frames), you can't parallelize anything. The same goes for rate-control (unless you're strictly CBR, which is similarly terribly wasteful).
This is why x264 performs it's first pass almost entirely on a single core (perhaps throwing 20% of the work onto a second core), and only on the second pass is it fully multi-threaded.
That is commonly how it's done, but you do lose some bitrate efficiency that way, and it doesn't parallelize perfectly as many operations need to be performed across the whole frame after the slices are reassembled, before the next frame/slices can be processed. x264 did this, but (somewhat recently) dumped this method for something better.
No (remotely decent) MPEG encoder made in the past 2 decades uses a fixed GOP-size. That's horribly inefficient.
Do *WHAT* to the luma and chroma channels?
That sounds like a core relay race... each one sitting idle most of the time, as it waits for data from the previous. It doesn't matter how fast you can do DCT and quantization, since the (slow) motion estimation, scene-change detection, and rate control first need to process the frame to decide how to change what happens to the next frame.
Parallel quantization is useless, because quant levels are different for each frame due to bitrate constraints and frame complexity. Parallel DCT is useless, since you need to know whether it's going to be an I, P, or B frame, and the differential from the previous frame, to do anything. etc.
A little bit of knowledge is a dangerous thing... You've mostly come up with lots of ways to keep the CPUs maxed-out, doing busy work that can't help speed-up encoding at all.