choppy video when source is 720p

[anastrophe]

recently bought a TivoHD. i have an older mitsubishi HDTV, it only supports 1080i for hidef - 720p is upconverted by the TV. so, i've set my TivoHD to use 1080i fixed, since it saves having the screen blank for a few seconds while switching res on different res stations. works fine. except for ABC. ABC is the only station i get that's 720p, and when i play back shows i've recorded from ABC in HD, they have this hard to quantify faint 'choppiness'. it's as if the video is skip-framed - camera pans a scene, and it definitely stutters all the way along. am i doing something wrong, or is there something wrong with my TivoHD? my signal is via comcast, motorola M-card, component-out, ...i think those are all the relevant details.

[ldudek]

recently bought a TivoHD. i have an older mitsubishi HDTV, it only supports 1080i for hidef - 720p is upconverted by the TV. so, i've set my TivoHD to use 1080i fixed, since it saves having the screen blank for a few seconds while switching res on different res stations. works fine. except for ABC. ABC is the only station i get that's 720p, and when i play back shows i've recorded from ABC in HD, they have this hard to quantify faint 'choppiness'. it's as if the video is skip-framed - camera pans a scene, and it definitely stutters all the way along. am i doing something wrong, or is there something wrong with my TivoHD? my signal is via comcast, motorola M-card, component-out, ...i think those are all the relevant details.

I have 1080i native on my tv and I use the "Native" setting for reception. I see no difference whats so ever in 1080i and 720p. I have tried setting it at 1080i fixed in the past and still saw no difference.

Just a suggestion: Try the "Native" mode. Yes, you will see a second or so of junk before the picture straightens out but it might help.

Otherwise, I would think this is an issue with your television and how it handles 720p.

[anastrophe]

thanks for the reply. i'll try native mode, but it can't be an issue with the way my TV handles 720p - since the tivo is feeding 1080i to it. i've had the TV since 2001, and never had this issue when watching 720P sources. however, since the tv does upconvert 720p itself, a different mode from the tivo that doesn't upconvert the 720p might make sense, since there's no need to upconvert it - the tv will do it.

[Stephen Tu]

Your post confuses me. Which model number Mitsubishi do you have? You say it "upconverts 720p" ... I don't think Mitsubishi TVs of that era even accept 720p; mine is newer (2004 model bought in 2003) than yours and only accepts 480i/p, 1080i. They only started supporting 720p input around the time they started switching to DLP instead of CRT. What STB were you using before the TivoHD? Almost certainly you were using the STB to convert 720p to 1080i before display.

Do you also get this "choppiness" on ESPN, Fox? Or no Fox HD in your area?

[anastrophe]

it's a WS-73909. early on, i used an antenna for HDTV signals, and the coax went straight into the back of the TV. the TV took the 720p over the air signal and displayed it 1080i. later i got a comcast/motorola DVR, and the component out from that went to the DTV component in on the TV - that displayed just fine as well. got the TivoHD a week and now i experience this problem where shows that were broadcast in 720p have choppiness - even though the signal being sent from the TivoHD to the TV is 1080i.

[bkdtv]

aanstrophe,

This may be obvious...but did you try rebooting your TiVo?

[Stephen Tu]

I see. The built-in tuner will convert OTA 720p internally to 1080i but the external inputs will only accept 1080i for HD, so 1080i fixed/hybrid are your only options for the TivoHD. I have a Mits with no tuner, similar input limitations, no problem w/ 720p stations on the TivoHD, it's not something inherent with the Tivo. Do you still have the Comcast DVR or the antenna hooked up? It would be helpful to compare different methods of receiving same signal, and/or different signals (no FOX to test?) as it might be a problem with the transmission not the Tivo. You might also search avsforum.com local HDTV section for the thread on your area, see if others are also having problems with that station. Rule out problems there first. "Choppiness" seems more likely a reception/recording problem, doesn't seem like a possible artifact of 720p-> 1080i conversion to me.

[mangas]

I saw the same thing--faint choppiness--today on Fox HD (other HD chans looked fine). I rebooted my tivo and problem was gone. my THD is connected to my 720p Toshiba via HDMI.

[anastrophe]

i watched some of the rams/niners game on fox this afternoon myself, and it does have the same problem. i tried switching to 'native' mode, but no change (oddly, it had no problem with the 720p signal even in native mode, so i guess the tv's internal brain was able to understand what to do there).

i'm going to reboot the tivo and see if it helps.

[ski4404]

I was seeing the same chop/stutter on 720p programs as well. Reboot fixed it. We'll see if it comes back...

[anastrophe]

yup - i did a reboot last night, and that "cured" the choppiness to the 720p source video.

sounds like a bug in the TivoHD based on the other reports. is there a place to report such things directly to Tivo?

[doconeill]

I just noticed that on both ESPN HD and ESPN2 HD with today's college games that I'm also getting the choppiness. This is on a TivoHD set to Native or 1080i Hybrid and a brand new Philips 1080p 47" LCD. I've been noticing it over the past couple days.

It's especially noticeable when they pan on the field where it seems to stutter, and the video in general looks worse than the SD channel. In one case, where they were showing a huddle up close, it looked like I was seeing the game through some heat haze - the field seemed to be rolling like waves on water.

Rebooting definitely helped. There is still that haze effect when they zoom in, but that may be in the actual feed. The video is definitely better and no stutter.

FYI, my source is FIOS w/Moto S-cards. Different TV, different source, but the TivoHD.

[ldudek]

I just noticed that on both ESPN HD and ESPN2 HD with today's college games that I'm also getting the choppiness. This is on a TivoHD set to Native or 1080i Hybrid and a brand new Philips 1080p 47" LCD. I've been noticing it over the past couple days.

It's especially noticeable when they pan on the field where it seems to stutter, and the video in general looks worse than the SD channel. In one case, where they were showing a huddle up close, it looked like I was seeing the game through some heat haze - the field seemed to be rolling like waves on water.

Rebooting definitely helped. There is still that haze effect when they zoom in, but that may be in the actual feed. The video is definitely better and no stutter.

FYI, my source is FIOS w/Moto S-cards. Different TV, different source, but the TivoHD.


Not sure but this seems to be a broadcast issue in regards to the haze.