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Comment by KaiserPro | Hacker News Reader

Gleaning useful 3d models from 2d images is rather error prone. Hence why all the cool kids are using wavelets, as they are inherently more reliable on 2d images.

Movie codecs are hard. However jpeg2000 and similar wavelet codecs (like Red's(those bashful camera people) REDcode, or dirac) can yield amazing compression ratios. The main problem is processing power.

Take Red cameras for example. When they first came out, it was a massive pain. Unless you spunked $5k on a super unreliable pci card you'd only get a maximum of 6 fps out of a 8-core mac (and it could only be a mac as there was no linux SDK) With the advent of 3 generations of CPU and better programming skill from people like avid, aja and the foundry we can get real time playback on a laptop.

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Using wavelets for encoding the textures makes sense. The challenge with JPEG200 is that you need the decoder in the read loop to know when to stop getting more detail. The degenerate case would be 2 triangles and a texture, but if you have existing world models, decimating the meshes and de-rezzing the textures appropriates would work. Read m post, it's still a Graduate Student algorithm, but cut scenes on consoles are an existence proof.

I understand that wavelet is amazing, but am a little sceptical about it being used outside of a few specialist areas. The general trend seems to be towards using increased storage and power to avoid compression (raw), rather than making files smaller.

The thing that replaced 35mm with a digital format is DCP. Basically its Jpeg2000 in disguise.

The problem with uncompressed formats at high resolution (like cinema 4k, and its smaller "UHD" cousin.) is that they eats bandwidth. Full res 4k images with basic RLE is 50megs. Thats 1.2 gigabyte a second. You're lucky to get that out of 10gig Ethernet.

Uncompressed anything is pretty much out of the reach of most consumers. iTunes, netflix, over the air, cable is all either MPEG2 or h.264

But surely nothing has really changed over the last 15 years. Processing power, storage, and bandwidth all get larger, but so do the images. Wavelets must be a great technology if you want to fit a HD video on a CD and play it with an expensive machine. I am not arguing against compression. But you have to admit that Jpeg2000 has been the next big thing for a long time. Surely it is cheaper to just use h264 and have more storage?

Depends on the application, In broadcasting for example bandwidth is painfully expensive, hence the shift from MPEG2 to h.264 for consumers (although in the US its much more complicated as everyone seems to recompress everything badly on TV. Its like watch a pirated copy.)

It just takes a long time to get from approval to acceptance. The other problem with JPEG2000 is that its not really a motion codec, so it doesn't degrade well over lossy links without special sauce. All of which is non standard.

I think this thread proves a point about compression. That it is about balancing different requirements rather than absolute performance in any one measure.

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