Thread: ESPNHD is Still Being Broadcast in 1080i

Title says it all: Why?

Thanks so much for your help, Darrell. I'll bug Wilt about it in the Yahho post. My theory is that it's done to save bandwidth. ESPN-HD is 720p at 60fps. It is widely agreed upon at avs that when cable and DBS show 1080i, it is usually more like 1440x1080 than 1920x1080. In addition, it is 60 fields per second instead of frames per second. So Voom is actually saving bandwidth by "upconverting" to 1080i.

broadcasting at 720p saves bandwidth, a good 1080i picture requires more.
Ive seen it on my local PBS station. They used to be 1080i until they created too many subchannels. They had to change to 720p to conserve bandwidth and stop the pixelation. Now its just a filtered, dull picture. No more "wow" or "pop".

Here was Wilt's answer:

Okay, here's the deal.
I was, once again, wrong. :-(
We had to keep it at 1080i because of a problem with a piece of timing
equipment in the video chain.
As soon as we can rectify that we'll put it at 720p again.
Figure it's better to have a stable 1080i than an intermittent 720p, purism
notwithstanding.
Sorry about the previous misinformation.
Wilt

Vurbano, I'm not trying to refight the holy war. My opinion is just based on the things I read through here:


http://www.avsforum.com/avs-vb/showt...hreadid=323602

Essentially, both 1080i and 720p have 60 million unique pixels drawn every second.

The thing is, 1080i is not really shown at 1920x1080, but at 1440x1080. I have to take the number crucnchers word for it over there, as I don't have the equipment. But at that diminished resolution, 720p takes more bandwidth.

However, like your point says, 720p is more forgiving of compression. Compress 1080i too much, and you get the artifacts. Not so with 720p. I guess this is what your TV station is doing. I also think my initial hypothesis was wrong. I'll believe Wilt. If they were trying to save bandwidth they could have just compressed 720p more easily than 1080i. So I'm an idiot, but at least I learned some new things.

Does Dish or DirectV also show ESPN in 1080i? Does anyone know?

Originally Posted by squicken

Does Dish or DirectV also show ESPN in 1080i? Does anyone know?

Dish does 720P.

Originally Posted by squicken

Vurbano, I'm not trying to refight the holy war. My opinion is just based on the things I read through here:


http://www.avsforum.com/avs-vb/showt...hreadid=323602

Essentially, both 1080i and 720p have 60 million unique pixels drawn every second.

The thing is, 1080i is not really shown at 1920x1080, but at 1440x1080. I have to take the number crucnchers word for it over there, as I don't have the equipment. But at that diminished resolution, 720p takes more bandwidth.

However, like your point says, 720p is more forgiving of compression. Compress 1080i too much, and you get the artifacts. Not so with 720p. I guess this is what your TV station is doing. I also think my initial hypothesis was wrong. I'll believe Wilt. If they were trying to save bandwidth they could have just compressed 720p more easily than 1080i. So I'm an idiot, but at least I learned some new things.

in 1/30th of a second 1080i produces a frame of 2 million pixels. In that same time 720p has produced 2 frames of 1 million pixels( two inferior picures which create a smoother transition) Your statement that 720p takes more bandwidth would mislead someone to think that anyone of its frames has more pixels than 1080i and thats a fallicy, you must divide that 720p pixel count by 2 because you are producing 2 pictures or frames. 720p is a parlor trick, a smaller pixel count run at a higher frequency.

Like I said, If you want to save bandwidth use 720p, the frame pixel count is 1/2 of 1080i. And you can compress the hell out of it. You cant with 1080i.