Diamond Pattern on Digital TV

[Jimb50]

I have a strange diamond or lattice work pattern showing up in digital live or recorded TV. My basic set-up is shown below. I have cable coming in then split, one going directly to one of the 1600 cards for analog TV, the other into the cable box, out via composite/S-video cable to the other 1600 card for digital TV. The pattern only shows up on the digital programming. It’s a back round pattern that is very apparent with certain colors, reds and blues. I have tried the following to correct the problem, none have worked:
Replaced composite/s-video cable, upgraded to current 1600 drivers, switched inputs on the 1600 cards. Also ran straight cable to cable box then 1600 card with other card disabled, no good. Running the composite/ S-video cable directly to the TV (Sony 27” CRT) from the cable box gives an excellent picture with no pattern. The same for viewing through WinTV. I’ve up loaded a short clip of the problem to Goggle video but it may not be visible due to compression and video size. The link:
http://video.google.com/videoplay?do...95401967203887
Thanks for any help.
Jimb50

[zoundz]

If you are talking about the chewing little squares in the background of your digital picture, you are looking at what are called macroblocks. These are the results of overcompression of the picture during the conversion to digital. There is absolutely nothing you can do about this other than to find another source for the channel. Different providers compress different channels by different amounts. Unfortunately an old electronics adage still holds: bandwidth is bandwidth. The more channels you try to push down a pipe with a particular bandwidth, the more you will have to compress them to make them fit. Unfortunately, most of the programming providers are fighting to find enough bandwidth in their distribution systems to hold all the channels they need and/or want to carry. The satellite providers have gone to multiple satellites and spot beam antennas to allow them to fit in all the channels. Dish Network is using MPEG4 compression which provides more picture in less bandwidth than MPEG2. ATT, Verizon, and many cable providers have gone to optical fiber distribution and IPTV schemes to increase available bandwidth and decrease the amount of data that is being distributed. Nonetheless, there is a shortage of bandwidth and a lot of unfortunate overcompression. Get used to it, it's not going away any time soon. Don't get me started on the crap that they call "HD". That's another rant....

[Para]

Originally Posted by Jimb50

I have a strange diamond or lattice work pattern showing up in digital live or recorded TV. My basic set-up is shown below. I have cable coming in then split, one going directly to one of the 1600 cards for analog TV, the other into the cable box, out via composite/S-video cable to the other 1600 card for digital TV. The pattern only shows up on the digital programming. It’s a back round pattern that is very apparent with certain colors, reds and blues. I have tried the following to correct the problem, none have worked:
Replaced composite/s-video cable, upgraded to current 1600 drivers, switched inputs on the 1600 cards. Also ran straight cable to cable box then 1600 card with other card disabled, no good. Running the composite/ S-video cable directly to the TV (Sony 27” CRT) from the cable box gives an excellent picture with no pattern. The same for viewing through WinTV. I’ve up loaded a short clip of the problem to Goggle video but it may not be visible due to compression and video size. The link:
http://video.google.com/videoplay?do...95401967203887
Thanks for any help.
Jimb50

Preface: I don't know a thing about this and am just asking....

zoundz,

Is a macroblock ever displayed as a diamond or is it always a square?

Why would a macroblock from the cable provider be visible only when encoded to mpg through Sage but not when signal is directly linked to the TV or displayed through another software (winTV)?

Just looking for some education since my initial read on this made me to think of another problem. Maybe I just read this all wrong though.

Thanks,
Steve

[stanger89]

Originally Posted by Para

Is a macroblock ever displayed as a diamond or is it always a square?

I don't see any diamonds in that video, but I do see a lot of macroblocking. With MPEG-2, macroblocking will always be 8x8 blocks.

Why would a macroblock from the cable provider be visible only when encoded to mpg through Sage but not when signal is directly linked to the TV or displayed through another software (winTV)?

Because while the blocking is probably subtle in the source, it will cause fits for the MPEG encoder in the HVR. If you've got an artifacty source, you need to crank the bitrate way up on your encoder or it will just pile more artifacts on top of the original ones.

Just looking for some education since my initial read on this made me to think of another problem. Maybe I just read this all wrong though

That tuner should be able to pull CBS HD directly off your cable, without going through the cable box, and without the extra encoding step.

[Para]

Thanks for the education Stanger. That all makes sense to me now.

Steve

[Jimb50]

I don't believe my problem is macro blocks. I've seen these before as pixilated blocks coming and going in digital transmissions. It really can't be seen in the video I posted, not sure why. The best way to describe it, when certain colors appear on the screen, a semi-transparent lattice overlays those colors. It really showed up in the darkroom scene of my posted video I also looked at the video on my 19" computer monitor, and it's barely visable as apposed to the TV sceen. It's also very apparent on some of the programs on the Game Show Network where they have a brightly colored backround. My TV is not HD, it's an older Sony Tube model 27". I'm thinking of going to a larger flat screen HDTV but would like to resolve this problem beforehand thinking a larger screen would only make it worse.
PS Happy holidays to all!
Jimb50