scott wrote:
>> Now compare the MPEG2 video back-to-back with the uncompressed 
>> original. Are you seriously telling me there is *no* detectable loss 
>> of quality?
> 
> Depends on the content - if your video consists of data you would 
> typically use PNG to encode rather than JPG, or where each frame is 
> vastly different from the previous one, then of course it's not going to 
> compress well. MPEG2 was designed to work well with real life captured 
> video, and it does that pretty well within the 10Mbit allocated by the 
> DVD standard.

Commercial DVDs do seem to do this quite well. (For some reason, DVDs I 
encoded myself aren't quite as good - although they're still not bad 
considering the compression ratio.)

> Another example, I made a video of some planets rolling about in POV, 
> the original uncompressed frames totalled 9.7 GB, after using MPEG4 the 
> video came out as 28MB, that's 350x smaller!  Really, there is no 
> noticeable difference in quality, I can't tell the difference by looking 
> at a freeze-frame in VLC compared to the original BMP.

That's some pretty steep claims. ;-)

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