NG
noggin Founding member
Jonathan H posted:
james2001 posted:
I wouldn'tbe suprised to find even HDTV will be an overcompressed mess. Heck, DAB & normal Digital TV is.


DAB overcompressed? You must be using a duff tuner. DAB clearly sounds better than FM!


Sorry - that is not the case for most DAB broadcasts - especially when compared to a properly installed FM tuner. This isn't a limitation of DAB - in some countries it happily outperforms FM. However the UK implementation has prioritised the number of stations available, rather than quality.

The MP2 audio encoding used in DAB which is relatively elderly, doesn't perform as well as a decent FM stereo signal at 128kbps when used in joint stereo mode. At 160kbs it is approaching FM quality, 192kbps is deemed about the same, and 256kbps is accepted to outperform.

256kbps is used in Germany for DAB- and for many radio broadcasts on Freeview and DSat, as well as most TV sound on Freeview and DSat.

192kbps is used for SOME Radio 3 broadcasts (though this drops to a lower rate when other part-time stations are on-air)

160 and 128kbps are the common rates for stereo UK DAB services - and 128k is noticably worse than a decent FM stereo signal.

128k DAB is most definitely not better than good FM stereo - though it is more robust.

Quote:

As regards digital TV compression, it is a fact that a perfectly set up PAL analogue picture is technically (and asthetically) better than most of the digital ones we get nowadays, certainly at the compression and bit rates that the majority of channels output.


An uncompressed digital component source is massively better quality than an uncompressed PAL composite source - however excessive digital compression can cause nasty artefacts in a digital source. However a component digital source will compress better than a PAL analogue one.

Quote:

How the broadcasters will output their images is still a matter for debate. But if you watch native HDCAM on an HD monitor, you cannot fail to be blown away by the quality and resolution.


Yep - and non-SR HDCam is not full-HD - it is subsampled 3:1:1 (1440x1080 Luma and even lower chroma res) - HD-D5 1920x1080 4:2:2 (compressed a bit) and D6 (1920x1080 uncompressed) both look even better. (HD Cam SR isn't subsampled to 3:1:1 but is still quite rare - though Sky are using it I believe, as it is the first Sony VT format that is 1280x720 capable as well.)