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Comment: Re:Something to think about (Score 1) 170

by devinoni (#32835472) Attached to: VP8 and H.264 Codecs Compared In Detail
As the VP8 vs x264 test is using SSIM, I found these important from the article about encoder cheating.

3. Making invalid comparisons using objective metrics. I explained this earlier in the linked blog post, but in short, if you’re going to measure PSNR, make sure all the encoders are optimized for PSNR. Equally, if you’re going to leave the encoder optimized for visual quality, don’t measure PSNR — post screenshots instead. Same with SSIM or any other objective metric. Furthermore, don’t blindly do metric comparisons — always at least look at the output as a sanity test. Finally, do not claim that PSNR is particularly representative of visual quality, because it isn’t.

How to spot it: Encoders with psy optimizations, such as x264 or Theora 1.2, do considerably worse than expected in PSNR tests, but look much better in visual comparisons.

4. Lying with graphs. Using misleading scales on graphs is a great way to make the differences between encoders seem larger or smaller than they actually are. A common mistake is to scale SSIM linearly: in fact, 0.99 is about twice as good as 0.98, not 1% better. One solution for this is to use db to compare SSIM values.

Comment: Re:Commercialisation (Score 1) 319

by devinoni (#31281414) Attached to: Senators Blast NASA For Lacking Vision

The Apollo project, even though run by NASA, was really a military project. It was an extension of the Cold War. It was all about beating the Soviet Union, and not about the science of getting to the Moon.

Any project to the Moon, to be cost effective, would have to use existing technologies. And it's questionable if the the President and Congress will fund NASA enough to develop those technologies.

Comment: Re:60% more bitrate for same quality (Score 2, Informative) 325

by devinoni (#28428367) Attached to: Concrete Comparisons of Theora Vs. Mpeg-4

I had to use the direct links, but noticed that the ogg version was 10% taller but the same contents. A skewing like this could easily explain bad perceived quality, did anybody else notice this or it is just my Firefox 3.5 beta on linux that's messed up?

10% taller visually? I think that's because that both videos were encoded at 704x576. That gives us an 11:9 aspect ratio for both, however the H.264 version has a 4:3 display aspect ratio set, so that it looks correct. It would be better if they had used square pixels for their raw source, so we don't need to compare anamorphic displaying of the videos as well.


+ - Senator to FCC: no broadcast flag for you!

Submitted by Flag waver
Flag waver (666) writes "Senator John Sununu (R-NH) will introduce legislation that will prevent the FCC from creating technology mandates for the consumer electronics industry. As a result, the FCC would be hamstrung in its efforts to revive the broadcast flag. '"The FCC seems to be under the belief that it should occasionally impose technology mandates," Sununu said in a statement. "These misguided requirements distort the marketplace by forcing industry to adopt agency-blessed solutions rather than allow innovative and competitive approaches to develop."' Sen. Sununu previously tried without success to remove the broadcast flag provisions from the massive telecommunications bill that died before reaching the Senate floor during the last Congress."

+ - Schools told not to deploy Vista

Submitted by ukhackster
ukhackster (978279) writes "Microsoft's hopes of making a big splash with Vista in the UK have suffered a blow. Becta, the agency which tells British schools which technology they should buy, has recommended avoiding the operating system for at least another year. According to Becta, there's no compelling reason for schools to move to Vista, or Office 2007 either. Becta was criticised late last year for hampering open source deployment in UK schools, but by cautioning against Vista it may now give Linux a boost."

+ - Sense of smell may be tied to quantum physics

Submitted by
SpaceAdmiral writes "A controversial theory that says our sense of smell is based not on the shape of the molecules that enter our nose but on their vibrations was given a boost recently when researchers at University College London determined that the quantum physics involved makes sense. The theory, which suggests electron tunneling initiates the smell signal being sent to the brain, could explain why very similarly shaped molecules have very different smells."

I am not now, nor have I ever been, a member of the demigodic party. -- Dennis Ritchie