How do over-the-air HD broadcasts compare...

if the image is perfectly still that is. Whcih is of course the problem because movies are not still. Add even a small amount of movement and its amazing how quickly this pristine image degrades. Its kind of shocking.

It was my understand that OTA HD broadcasts are an either/or situation. Either you have it or you don't. There is no image degradation due to weak signal. It just cuts out. The image degradation seems to be coming strictly from the compression in the broadcast itself.

For example, an Expedia ad came on last night. White background, small little bit of text in the middle of the screen with a little globe and airplane graphic above it. The stationary "Expedia" text looked crisp and clean the entire time. The little airplane swirling around the cartoon globe just above this text looked like blurry pixelated garbage. As soon as it stopped spinning and became still it became just as crisp as the text.

OTA looks the best over cable and Sat.

I have a terk square shooter outdoor ANT and dish network, I use the OTA ant for local shows because it looks better on my set, not sure why but it may have something to do with hooking it straight to the TV vs going through a sat or cable box.

gabe

great observation gabe...yes it does look better going straight to your set. here is why; the signal you're picking up with your antenna
ota is coming straight from your studios in an uncompressed form. that is true hd video, as well as pure digital audio signal getting to your tuner.
i am a technician with one of the country's larger cable companies, and i am also a subscriber to directv. i have high-end audio/video equipment in my home and i closely monitor all possible types of high definition broadcasts.
first, just let me get this out of the way...a 1080p tv and a blu ray disc is just about unbeatable! anyone that doesn't have this yet needs it!
as for cable/satellite/ota broadcasts are concerned, the ota, uncompressed signal is best. however, you do need to optimize the signal reception and there are a number of factors that come into play as to how to acheive this. such factors are the ant. you are using, as well as the location of your home in proximity to the broadcast towers, to the layout of land and buildings surrounding your home. i have the high-end outdoor antenna that works just fine, and i have also tried an array of indoor antenna's, both non-amplified and amplified. what worked for me was starting cheap and trying them out to see what worked best. your tv tuner will also play a role in how well you pick up ota broadcasts also. with my newest television, the ota antenna that i am most pleased with is an indoormodel with a $49. price tag. it is the Phillips MANT510. it is the most used at this point. so just start cheap and see how lucky you get.
as for cable hd signal, i have to say it is very good. or at least from my company it is. but it is a compressed signal. we get the signals from the broadcasters in an uncompressed format, but it has to be compressed for us to send it out through the cable plant. however, if you've got a tight cable company in your area, and the last technician at your home made sure your home was clean (undamaged shielded cable, proper fittings, tight connections, no ingress/egress, proper levels and values) then you're really in for a treat. the difference you will see is mostly heard. the audio won't be as crisp, atlthough you will still get what is being broadcast. and cable companies have optical audio output and HDMI output set tops. but your run-ins with tiling and freeze frame and rainbow effect will be almost non-existent. it is a pure joy. well worth having and most cable operators now have all locals in HD as well as your major sports and movie networks in HD.
as for satellite....this is actually my least favorite of the three.
audio from satellite is almost always better than the other two sources. but, seeing as directv is not a studio themselves, i would have to think that they have to degrade the source that they are receiving in order to get it to us. how many times, i really don't know. i know they advertise a lot more HD than cable, and they are telling the truth. they have a lot of HD channels. but in reality, about half of them don't look as good as some cable companies' digital broadcasts. but, this is just my opinion, and i try to be as unbiased as i can be. i actually let the directv guy park in my front yard! with my cable truck in front of my house.
so, take this and run with it. i hope it helps some of you to find what you're looking for. and trust me, when you get it you will know it....and you will love it!
one more thing before i go...a good place to start as far as determining how your house sits and the type of signal you should be receiving in your area, go to solidsignal.com. under antenna tech help, click on HDTV channel lists. from there you will be able to pick your immediate area or an area very close to yours. you can get detailed maps that display your homes location and the proximity to your local towers, including direction, layout, obstructions, etc.
and it will suggest types of and strength of ota antenna's for you to consider.
happy viewing!

The video is compressed and compressed a lot!!!!
All digital video is compressed using MPG2 compression!!
That Max bandwidth of an OTA signal is 18megabits and if the station has sub channels like NBC and ABC use, the main channels are compressed even more. John

You are correct about the compression issue. This is a good example of a technician not being familiar enough with the basics of the technologies/hardware/software they deal with on a daily basis. No wonder consumers get mad sometimes(!)

-Pedro

MP2 is the analog to digital encoding, not compression. It changes the bit rate significantly when it makes the conversion from analog to digital so the data stream is smaller, but it's NOT compressoin. It's also what's considered lossless encoding, meaning NONE of the originating analog signal, video or audio, is lost. If the image or sound is captured in high definition, it's encoded and transmitted/broadcast in high definition with ZERO loss. OTA uses MP2, of which the data rate is still too high for cable or satellite.

MP4 which is used by satellite and cable companies takes the originating MP2 signal and squashes it so they can jam 200 channels down one wire, making the picture look not as crisp. That's why cable and satellite will never be able to touch OTA for picture quality.

I'm using a Antennas Direct Clearstream 2 antenna into a 65" projection TV. In 1080i I can see the dimples on the football.

MPEG is one of the most popular audio/video compression techniques because it is not just a single standard. Instead it is a range of standards suitable for different applications but based on similar principles. MPEG is an acronym for the Moving Picture Experts Group which was set up by the ISO (International Standards Organization) to work on compression.
http://www.tek.com/applications/video/mpeg_derivatives.html?WT.srch=1&WT.mc_id=ppc,ggl,vid_aw_us_us_ngt,k3AF4,s,2954932693&

IS THERE A DIFFERNCE ? I GET BOTH ON MY OTA ANTENNA. I'VEUSED MY OTA ANT ALL OVER THE COUNTRY AND I PICK UP AN AVERAGE OF 50 HDTV CHANNELS.


?

I bought a powered V wing antenna, (don't recall the brand but got it at Radio Shack; $75). Mounted it on a pole about 20 to 25 feet up. Just stuck it in the ground next to the house and attached it with a bracket at the roof eves. Works great even though I live in the woods. Rain on the foliage can cause problems but otherwise a pretty good picture.

It's attached to my computer monitor however, (30 inch 1080i Olivea). For regular viewing, I use Direct TV on a 55 inch Sony A3000.

Mainly due to the fact that there are bandwith restrictions with Satellites. Cable is pretty good as well, then there are your satellite broadcast.

Not all digital broadcasts are on UHF. Once the analog broadcasts are ended, some digital transmissions will be moved back to VHF. In my area, after the transition, there will be three stations transmitting on VHF channels.

Your signal must be weak. You probably live a little too far from the OTA broadcast source. I use an old rabbit ear antenna and get a beautiful picture from local CBS, NBC, Fox, ABC, PBS high definition broadcast channels. Absolutely no pixellation!! But then, I live just accross the river from local broadcast stations in downtown New Orleans. Try an outdoor roof antenna or a TERK or Radio Shack HDTV indoor antenna. You may have better luck with that.

I have my outdoor antenna connected through my Dish Network 722 receiver. I ended up going OTA because Dish wasn't broadcasting the locals in HD until about a week ago and I wanted to watch the NCAA tourney in HD. According to my Dish Network receiver, my OTA signal strength on the CBS station is 96 (0-100), but the broadcasts still suffered from the blocking during movement. I've since watched NBA basketball on the ABC affiliate that is only running about 76% and not had the same problem. The NBC affiliate doesn't have the problem either, but the transmitter's only six miles from my house and it's always 100%. The message I'm getting is that OTA broadcasts are never compressed?

an outdoor antenna. I might be willing to buy a better quality indoor antenna for the few times I just have to see something being broadcast on network TV or PBS.

I checked antennaweb.org and I am in a city center between 8 and 14 miles away from all the digital broadcast towers in my area. All the houses are 1 and 2 story but there are a lot of big 50-60 foot mature trees in the neighborhood.

The rabbit ears I am using are from the late 90's and have a fine tuning knob at the base and a about a 8" loop at the base for UHF channels. Is there any type of indoor antenna that would make a difference over what I already have or is this as good as it will get on an indoor antenna?

RADIO SHACK HASA FINE OTA ANTENNA THAT I PAID ABOUT $25 FOR.....ALSO TRY MONOPRICE .COM AND CROTCHFIELD.COM

AND PROVIDENCE HAS ADVANTAGES. EACH CITY HAS AN ABC, CBS, CW, FOX, NBC, AND PBS STATION AFFILIATE. (zip: 02703)

I HAVE COMCAST CABLE (RIP-OFF) for both sets, and an antenna for EMERGENCIES. There POTENTIALLY over 40 receivable OTA signals in my area.