Thread: Tivo V6 The change in storage space needed for recordings on VM
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Old 19-12-2020, 21:23   #8
jfman
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Re: The change in storage space needed for recordings on VM
Quote:
Originally Posted by cheekyangus View Post
Many thanks spiderplant.

I had a feeling new encoders were a part of it, I recall them being mentioned recently but have no idea how long they've been installed. I couldn't remember when the HD channels switched to MPEG4 so wasn't sure what to attribute to the change. How much bigger were the MPEG2 HD channels on VM just before they were superceded?

It's impressive the results, I couldn't really see any difference when I compared scenes.
Some of the initial MPEG-2 HD broadcasts initially were around 16-18 Mb/sec taking up about half of a 38 Mb/sec 64 QAM transport stream (minus overheads).

A quick skim on Digitalbitrate has the current MPEG4 HD channels varying anything between 2 and 7 MB/sec as this depends how many channels are being squeezed in and what prioritisation they are given. Digitalbitrate is currently reporting BBC 4 HD averaging 1.8.

You are probably comparing when the number of HD channels was capped at about 6 per transport stream (a straight average of 7.5 MB/sec once overheads taken out, with BBC4 a lower priority compared to other content on the stream).
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