DirecTV Launches 21 HD channels > HD-LITE

HD-LITE

The "HD-Lite" you're referring to is the old MPEG2 streams. The new ones are all MPEG4, and look fantastic... People who whined about the MPEG2 stuff and kept their OTA antennas for that reason have generally been saying they can't tell the difference between their OTA and MPEG4. It's good stuff...

Most of the MPEG2s looked good too, but you could see issues in certain situations.

Adam

reply to dvd536
Depends on how you define "HD-Lite".

Ever since D* started some transmissions (locals in some cities, and RSNs in some DMAs) in MPEG4, most people can't tell the difference when compared side-by-side with an alternate service provider (cable) and in some areas it looks better than the alternate.

Bottom line - if you can get locals OTA, you're not going to beat the quality with any other service provider - because there's no additional compression added to the stream - so stick with OTA for locals.

In many markets cable companies do not recompress OTA HD streams at all. They remux the same MPEG-2 data into a QAM stream for your cable box to pick up. So, the quality may be exactly the same as OTA. So, you may very well have superior picture from Cox.

Problem is unless you have a QAM capable tuner card AND an OTA source to digitally compare the data, it's not immediately clear whether or not your OTA source is being recompressed or not. There's other factors such as the mpeg-2 decompression hardware built into the cable box which can affect perceived quality as well.

So with cable, you may have either EQUAL or INFERIOR quality to OTA.

Mpeg-4 providers like AT&T U-Verse and DirecTV are almost certainly taking the mpeg-2 sources from OTA and transcoding to mpeg-4 which will always introduce some quality loss of some sort.

Perhaps at some point stations might "simulcode" directly to mpeg-4 for AT&T and DirecTV, which could result in possibly better picture quality than the OTA source, but for now, it's always going to be inferior to OTA. Whether it's superior or inferior to cable depends on the cable provider.

As far as that goes... how is Time Warner at your end of the city on HD ?
--
Canada = Hollywood North

reply to djrobx
Actually, at least with Comcast of Prince George's County, they *can* be compared heads-up. What Comcast of Prince George's County (750 MHz ADS cable plant) does with the OTA channels is three-fold:

1. The existing analog signal is cleaned up and forwarded down the plant.
2. The the digital primary signal (whether HD or not) is remuxed, converted into a 256QAM stream, and (if necessary) relocated to a new channelspace, then (like the analog signal) forwarded down the plant.
3. The digital secondary/tertiary/quaternary/etc. subchannels (invariably SD) go through a process similar to that outlined in #2 above.

While, thanks to increased deployments of HSI and CDV/VoIP, the HD channels are not in the same channelspace on the Comcast cable system as they would be OTA, they can be rather easily compared to their still-analog OTA counterparts (in fact, in the case of the two 1080i stations, WRC-DT and WUSA-DT, it can be done Rather Easily; their analog signals on the cable system are still at channels 4 and 9; meanwhile, their 256QAM equivalents are next to each other but moved considerably north at 122.1 (WUSA-DT) and 122.2 (WRC-DT). There has *never* been any case where the analog signal has been as good as the 256QAM signal, for either channel, even with wholly SD content.)
That, at least to my eyes, would seem to imply that a full-bandwidth 256QAM signal, even one containing SD content, is simply the best SD signal possible using current technology. (While my HDTV, a Philips 42PF7320A/37A, does have PixelPlus (first-generation) PQ-enhancement technology, I (for my own reasons) have it turned *off*.) While there may indeed be differences in how the *digital* signal is treated over a cable plant compared to its treatment over the airwaves, it usually takes a marked maladjustment (or outright hardware failure) for a digital HD OTA channel over a 750 MHz or greater cable plant, to be inferior to the same signal transmitted OTA, even given a quality antenna to compare it to. However, the treatment the same signal goes through for satellite retransmission is different, and usually involves an extra conversion step (or two) more than what the same signal goes through enroute to a cable STB or other 256QAM receiver, such as one within a TV or PC. However, with a quality cable plant (again, 750 MHz or greater) you may actually have a picture quality *superior* to that of OTA, depending on the quality of the OTA reception equipment, for two major reasons:

1. For OTA carriage, Comcast of Prince George's County has a master OTA antenna reception tower at their headend on Marlboro-Ritchie Road; it's a scant twenty miles from the major stations with which they have retransmission agreements. (In every case except for one station, this tower is closer to the station than I am; that one station is northwest of me, whereas I am *southwest* of the cable headend.) However, even with the single odd station, there are going to be line-of-sight and atmospheric issues between me and the transmitter (with all the stations) that have to be taken into account (and it's not cheap).

2. Just putting up an antenna onto a roof is not exactly an inexpensive proposition. (Then consider the cost of a highly reputable installation firm, such as Fairfax Antenna (northern Virginia) or Davis Antenna (suburban Maryland).)

3. Lastly, there are no signal amplifiers in the air between me and the transmitting antenna; there *are* signal amplifiers between me and the cable headend. (That is part of the reason for those fees that a cable system collects; to take the pain and suffering that you would be going through dealing with the wear and tear of a household antenna onto themselves!) At its core, every cable-TV plant starts as a SMATV (Single Master Antenna TeleVision) system; this part is dedicated strictly to OTA. (While some cable plants also have dedicated microwave or even fiber-optic backhaul backups in case of transmitter or antenna failure at the source end, the SMATV core is still the primary OTA signal source.)

4. AT&T U-Verse functions similarly (in fact, so does Verizon FiOS TV); however, their means of signal forwarding to the customer differ both from cable TV, and from each other. U-Verse uses high-priority (but non-dedicated) feeds from their VHEs to each U-Verse-enabled central office; from there, the signal is sent over fiber optics to each node. Lastly, the signal is then sent over non-dedicated copper to the customer. FiOS TV differs from U-Verse in that it uses *dedicated* fiber-optic wavelengths over the entire distance from the VHE to the customer premises (it takes no bandwidth from any other VZ traffic); it is only at the ONT that the signal is changed to the mirror of that leaving a 750 MHz cable-TV plant (in effect, that is exactly what the ONT is for FiOS TV; a one-household cable-TV plant). As opposed to the signal *amplifiers* that can be necessary if you have many TVs installed in a household served by cable-TV, you may actually need signal *attenuators* that actually *reduce* signal strength depending on how close you are to the ONT. (The equivalent of too *much* antenna, rather than too *little*.)