Digital TV video bitrates – September 2011

The other day Prime TV started broadcasting a new channel in its 6/60 bundle here in Canberra, and presumably elsewhere. This is called ‘Television 4’ and is numbered channel 64. It carries primarily advertorial stuff (exercise programs, Foreman grills and whatnot), plus some educational promotional stuff, apparently largely in consort with the University of New South Wales.

So, time to update the video and audio bitrates for digital TV again. (The last update was in January this year.)

To gather this data, on 19 and 20 September I  recorded six hours, in three separate chunks, from each station onto a Topfield PVR. Then I whacked the minutes and megabytes into a spreadsheet, did the division and subtracted the audio bitrate. These figures probably overstate things a little, depending how much extra the Topfield adds into its recording stream (not much, I imagine, because they are standard MPEG files), and the presence of subtitles. So, really, only the first two significant figures of the video bitstream should be considered.

Also, remember, this is in Canberra. The figures may well be quite different elsewhere. Our commercial stations still broadcast their HD as 1,440 x 1,080, for example.

If anyone would like to repeat the process in a major capital city, I’d be happy to email through the spreadsheet on condition that you provide the information back for publication here in due course.

Station Ch Audio
video bitrate (Mbps)
ABC1 2 MPEG 2.0 256 720 x 576i 5.00
ABC2 22 MPEG 2.0 256 720 x 576i 4.15
ABC3 23 MPEG 2.0 256 720 x 576i 4.16
ABC News 24 24 DD 2.0 256 1280 x 720p 7.89
SBS ONE 3 MPEG 2.0 192 720 x 576i 4.22
SBS TWO 32 MPEG 2.0 192 720 x 576 4.40
SBS HD 30 MPEG 2.0 192 1280 x 720p 8.99
SC10 Canberra 5 MPEG 2.0 256 720 x 576i 5.14
ELEVEN 55 MPEG 2.0 256 720 x 576i 4.16
One HD Canberra 50 DD 2.0 448 1440 x 1080i 11.47
PRIME Canberra 6 MPEG 2.0 256 720 x 576i 4.66
7TWO Canberra 62 MPEG 2.0 256 720 x 576i 4.67
7mate Canberra 63 DD 2.0 256 1440 x 1080i 8.54
Television 4 64 MPEG2 256 720 x 576i 2.59
WIN Canberra 8 MPEG 2.0 384 720 x 576i 4.94
Canberra GO 88 MPEG 2.0 384 720 x 576i 4.46
GEM Canberra 80 DD 2.0 448 1440 x 1080i 9.78

ABC has reduced the bitrate on News 24 by over 1Mbps and fed that back into the three SD channels. The new channel seems to have come at the expense of Channel 6 and Channel 60. Even so, it has a very low average video bitrate, and the picture quality suffers accordingly. In particular, there is quite a bit of macro blocking.

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