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Originally Posted by Chris T
Offtopic, but I remember a similar discussion on here a while ago about DAB quality - that on digital radio, even the Beeb is going for quantity over quality and broadcasting streams that are effectively sub-FM standard on certain channels.
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Certainly are, from wiki
Currently, 98% of all stereo radio stations on DAB in the UK use 128 kbit/s joint stereo, which is incapable of providing the same level of audio quality as FM. Speech services usually use 64 kbit/s mono. The only good audio quality service is currently BBC Radio 3, which is usually transmitted at 192 kbit/s in true stereo, but does not sound as good as it does on FM.
The audio is encoded as MPEG 1 Layer 2 (MP2), which is approximately 50% less efficient than MP3, meaning that MP2 requires a 50% higher bit rate to achieve a given level of audio quality than MP3. For example, blind listening tests have shown that MP3 now performs very well at a bit rate of 128 kbit/s, and MP2 would require a bit rate of at least 192 kbit/s to provide the same level of audio quality. Some channels, such as E4 use a shorter picture to reduce bandwidth also.
NTL don't encode / reencode the signals, just play them out, so you should see the same image from all platforms.
EDIT - on the original picture topic, it is all down to bandwidth again. When DVD and compressed encoding first came there was a lot of concern that cartoons, animation, old movies would not convert well, but cleanup, cell realignment and general care in encoding and use of good bandwidth as ensured this has not happened. Just take a look at Bambi, or the Incredibles (or apparantly Japanese Animi) to see for yourself. But DVD can offer up to 8MB of bandwidth for the picture and audio.