You can't apply simple arithmetic like that to MPEG-2 compressed video.
The original 4:2:2 sources are hundreds of megabytes per second uncompressed, and the resulting bit rate of the compressed stream depends far more on the compressor settings and compressability of the source than the original resolution. Reducing resolution before compressing enables you to use lower bit rates and maintain the same quality.
Clock cycles per pixel. Sure look's linear and scalable to me. Cpu power to encode is another story., but you can't make simple assumptions like you have about the bit rate being reduced by the same percentage as the number of pixels in a frame.
Heck, I've seen higher bit rates out of HDNet's 1440x1080 than on OTA full 1920x1080i.
Interesting Bottom line - can you give us one example - just 1 example - of a service with 2 HD and 1 SD Channel on a TP that you can claim is good?
Unfortunately his calculations on the bitrate are not very accurate - as shown on AVSFORUM where its reporting OTA ATSC NBC shows in Phoenix at 26Mbps - even though the NBC Affiliate has a SD Multicast and their HD Channel is set to a max of 15.00Mbps.
http://www.avsforum.com/avs-vb/showthread.php?p=9392433&&#post9392433
http://www.avsforum.com/avs-vb/showthread.php?p=9368127&&#post9368127
http://www.avsforum.com/avs-vb/showthread.php?p=9381905&&#post9381905
HDNET is sent out at a constant 17.57 Mbps Video on 127W. Add in the 384k of audio and other mux info - it was set at this bitrate to allow for HDNET and HDNET Movies to just squeeze in 1 38.81Mbps Cable 256 QAM.
The readings TSREADER gives you are on the high side from what this shows.
That is outdated information. HDNET and HDNMV were down-rezzed to 1440x1080 last August. ESPN has always been 1280x720p. RUSH is a VOOM 1280x1080 channel. I can't recall if TNTHD and/or Discovery HD have been left at 1920x1080. Wouldn't matter a whole lot for TNTHD given how much S T R E T C H - O - V I S I O N they show on it.
If they are giving HDNET 14-15 Mb/s, then there is no reason for it to not be 1920x1080. That is more than sufficient to produce a good full rez picture ... although it can be even better with 16-17 Mb/s.
American Movie Classics AMC 287 7 110° E*8
HD Net (8PSK) HDNET 9422 7 110° E*8
HD Net Movies (8PSK) HDNMV 9423 7 110° E*8
HDNET TS sample (Dead Like Me)
Resolution = 1920 x 1080i
FPS = 29.97
Apect Ratio = 16:9
Avg TS Rate = 14.62 Mb/s
Stream Type = MPEG-2 MP@HL VBR
Nom bitrate = 14200000 Bit/sec
Peak = 17555000 Bit/sec
Average = 16422000 Bit/sec
Chroma format = 4:2:0
http://img263.imageshack.us/my.php?image=hdnetil5.jpg
http://img248.imageshack.us/my.php?image=hdnet2iz9.jpg
Yeah, right - look at her bottom lip . Sure, it is not 17 or 19 Mbps.A 1920x1080i HDNET frame grab
http://img402.imageshack.us/my.php?image=1920x1080iya8.gif
Negative... that's three HD streams.
Yeah, right - look at her bottom lip . Sure, it is not 17 or 19 Mbps.
American Movie Classics AMC 287 7 110° E*8
HD Net (8PSK) HDNET 9422 7 110° E*8
HD Net Movies (8PSK) HDNMV 9423 7 110° E*8
HDNET TS sample (Dead Like Me)
Resolution = 1920 x 1080i
FPS = 29.97
Apect Ratio = 16:9
Avg TS Rate = 14.62 Mb/s
Stream Type = MPEG-2 MP@HL VBR
Nom bitrate = 14200000 Bit/sec
Peak = 17555000 Bit/sec
Average = 16422000 Bit/sec
Chroma format = 4:2:0
http://img263.imageshack.us/my.php?image=hdnetil5.jpg
http://img248.imageshack.us/my.php?image=hdnet2iz9.jpg
VBR video sample rate will be all over the place but a terrestrial (over-the-air) transmission carries 19.39 megabits of data per second. Terrestrial (local) broadcasters use 8-VSB modulation that can transfer at a maximum rate of 19.39 Mbit/s, sufficient to carry several video and audio programs and metadata. Cable television plants generally operate at a higher signal-to-noise ratio and can use 16-VSB or 256-QAM to achieve a throughput of 38.78 Mbit/s, using the same 6 MHz channel.
HDNET TS sample (Dead Like Me)
Resolution = 1920 x 1080i
FPS = 29.97
Apect Ratio = 16:9
Avg TS Rate = 14.62 Mb/s
Stream Type = MPEG-2 MP@HL VBR
Nom bitrate = 14200000 Bit/sec
Peak = 17555000 Bit/sec
Average = 16422000 Bit/sec
Chroma format = 4:2:0
http://img263.imageshack.us/my.php?image=hdnetil5.jpg
http://img248.imageshack.us/my.php?image=hdnet2iz9.jpg
It isn't hard for any projection HD CRT gun to hit the full 1080 lines of vertical resolution.
Using 7" CRTs, most sets can hit around 1400 lines of horizontal resolution.
Using 9" CRTs, they can do around 1600-1650 lines.
Given that they have superb contrast, the resultant picture can be fabulous when properly aligned and calibrated. Many of the most demanding videophiles and certified calibration specialists use CRT-RP. The most important factor to many of these demanding viewers is contrast ratio. Having true, deep blacks set behind vibrant colors adds a 3-D aspect to a picture that is lacking on many digital sets.
It is only the very latest generation of DLP, LCOS, and plasma (not LCD yet) that are beginning to eclipse the overall picture quality of CRT-RP. New 1920x1080p sets with high contrast ratios are getting there.
When I was shopping a couple of years ago, I had the opportunity to compare many sets under many lighting conditions and full opportunity to adjust and tweek each one to "get them right." I couldn't find a single sub-$5000 set that could compete with a properly set up $1500 CRT-RP. That was before this last round of true 1080p and contrast improvements.
Unfortunately all most people have to go on are the grossly out of adjustment CRT-RPs sets that sit in the corners of HDTV showrooms. They have no idea how great a picture those sets can produce.