On 14/04/2011 17:03, Darren New wrote:

> I'm pretty sure the individual blocks of jpeg are independent (unlike
> PNG for example). You ought to be able to de-convolve an entire jpeg in
> parallel at least, once you de-huffman it.

I believe they are. Note, however, that "progressive JPEG" exists. 
That's where the data is reordered so that you can generate a low-res 
preview quickly, after only downloading the first few KB of the file. I 
don't know how that affects the ability to process the thing in 
parallel. (I'm not sure whether the rearrangement is a simple 
permutation, or whether it depends on the data. The former shouldn't 
impede parallel processing. The latter would.)

Post a reply to this message