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Comment: Re:And the moral of the Story is... (Score 2) 158

by simonloach (#39938429) Attached to: The Wretched State of GPU Transcoding

A GPU is better suited to some kinds of massively parallel tasks, like video encoding. After all, you're applying various matrix transforms to an image, with a bunch of funky floating point math to whittle all that transformed data down to its most significant/perceptible bits. GPUs are supposed to be really really good at this sort of thing.

And there's your problem.

An h.264 encoder takes a frame of video and splits it up into 16x16 pixel macroblocks. Each macroblock is heavily dependent on those surrounding it (spatially and temporally). For an intra block, a prediction of the content of the current block is made using the decoded content of the top and left blocks. For inter blocks, a previous frame is used as a reference. The decoder has no idea what the original source file looked like, so any predictions made in the encoding process must be from the decoded frames. This leads to massive data dependencies in the encoder which cause a cascade of blocks that need to be encoded before the current block can be.

Many, many, people have come onto #x264dev and tried implementing GPU accelerated encoding, some of them with impressive backgrounds. All of them left once they realised how difficult this problem is.

Comment: Introduction to programming (Score 3, Interesting) 194

by simonloach (#37331240) Attached to: Ask Director Eben Upton About the Raspberry Pi Foundation

The raspberry pi is meant to introduce programming concepts to school-level children.

My question is: How are you planning on doing this from a UI perspective? The BBC micro (as far as I can tell, a little before my time) simply dropped the user into a BASIC prompt and left the rest to their imagination. This seems like a pretty fundamental design question for the raspberry pi, but I haven't been able to find a clear answer yet.

Comment: Re:deniers come out in 3 .. 2 .. 1 .. (Score 3, Informative) 658

by simonloach (#27968895) Attached to: Ocean Circulation Doesn't Work As Expected

If we have to choose between spending a trillion dollars now and spending a trillion fifty years from now, which should we do?

I think you've got the wrong idea.

The Stern Review came to the conclusion that the benefits of strong, early action on climate change considerably outweigh the costs.
Waiting fifty years might be the worst thing we could do.

Comment: x264 (Score 1) 313

by simonloach (#27873245) Attached to: Theora Ahead of H.264 In Objective PSNR Quality

Biased, I know, but here's what an x264 developer had to say in response.

Quote: They apparently used the worst possible x264 settings (yes, subme 0 and so forth) in order to make Theora look better--if Theora didn't win such a test I would be shocked indeed! Instead, they just proved the fact that they're a bunch of liars who are no better than the worst of the proprietary companies they claim to compete against.

Comment: BBC has the right idea (Score 2, Informative) 292

by simonloach (#24353503) Attached to: Lack of Bandwidth Oversight Damages HDTV Quality

I have a lot more respect for the BBC after checking out their high definition service. As high definition is just kicking off in the UK they have had the opportunity to use the very latest h264 standards. They show programmes in 1080p at around 16Mb/s which looks great on a decent tv.

Looking at providers in the US it seems they're stuck with outdated mpeg2 standards which really doesn't do anything for the picture at low bitrates.

The only trouble is that hardly anything is filmed in HD in the UK. NOTE TO BBC: I want to see Jeremy Clarkson being eaten by dogs in full 1080p glory!

Music

+ - Major UK music retailer Fopp forced to close->

Submitted by simonloach
simonloach (974712) writes "Music retailer Fopp has announced it is shutting down its 105 shops, as the firm becomes the latest victim of the slump in CD sales.

On Friday June 22nd 2007 the company closed all branches across the company for 'stock taking' and said they were in talks with their bank. A week later the company announced it was a temporary closure in all its outlets and its online venture. Staff were informed on the 28th by management that they would not be receiving their monthly pay (just hours before payday).

Fopp — known for cheap CDs, DVDs and books — has called in accounting firm Ernst & Young as administrators. "The stores have been closed by management and shop staff sent home," said Colin Dempster, one of the joint administrators at Ernst & Young.

Similar factors led to HMV announcing on Thursday that its annual profits had more than halved."

Link to Original Source
Biotech

Photosynthesis May Rely On Quantum Effect 234

Posted by kdawson
from the good-exitations dept.
forgethistory sends us to PhysOrg for a summary of new research suggesting that the near instantaneous energy transfer achieved by photosynthesis may rely on quantum effects. From the article: "Through photosynthesis, green plants and cyanobacteria are able to transfer sunlight energy to molecular reaction centers for conversion into chemical energy with nearly 100-percent efficiency. Speed is the key — the transfer of the solar energy takes place almost instantaneously so little energy is wasted as heat. How photosynthesis achieves this near instantaneous energy transfer is a long-standing mystery that may have finally been solved."

The solution of problems is the most characteristic and peculiar sort of voluntary thinking. -- William James

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