What's happening with these screenshots?

[RSVP]

Captured with a Conexant C2388x chip, NTSC, 720x480, S-Video in, Digital Cable box source (MPEG-2 TS -> NTSC). Problem occurs regardless of capture software used.

Large splashes of orange color have vertical bands.

Lettering has blocks around the edges.

In the last shot, things seem fine (from the exact same source, no settings changed).

Any ideas what's going on?


Other images available if needed.


http://images5.pictiger.com/thumbs/3f/0931dea54bfdae2c432e1892b045e83f.th.png (http://server5.pictiger.com/img/110249/picture-hosting/snapshot-20060228111613.php)


http://images5.pictiger.com/thumbs/18/86fd19bb7655407db3c8e8ee58360218.th.png (http://server5.pictiger.com/img/110268/picture-hosting/snapshot-20060228111645.php)


http://images5.pictiger.com/thumbs/07/3019d73e6796145804d7dab14ad29307.th.png (http://server5.pictiger.com/img/110270/picture-hosting/snapshot-20060228111918.php)

[tedkunich]

Captured with a Conexant C2388x chip, NTSC, 720x480, S-Video in, Digital Cable box source (MPEG-2 TS -> NTSC). Problem occurs regardless of capture software used.

Large splashes of orange color have vertical bands.

Lettering has blocks around the edges.

In the last shot, things seem fine (from the exact same source, no settings changed).

Any ideas what's going on?



Looks like the saturation is way for that particular commercial. I notice that all the time on DTV. Unfortunately I do know of anything that you could do other than to turn down the saturation level on the cap card at the expense of muting the sat of the vid of interest.

T

[RSVP]

So would it be safe to say the problem is the source and not the card?


Here's another shot from a different commercial. The problem looks like "Dot Crawl", but that shouldn't happen with S-Video right?

http://images5.pictiger.com/thumbs/59/f049f00bd83d8535f67e24e280b67559.th.png (http://server5.pictiger.com/img/127271/picture-hosting/snapshot-20060301180328.php)

[DrP]

Its quite possible for the dot crawl to be encoded in the video - ie somewhere along the line an encoder was fed with poorly handled composite video. Every decoder from that point on, even if you grab the svideo output will have apparent dot crawl.

[tedkunich]

So would it be safe to say the problem is the source and not the card?

Yep


Here's another shot from a different commercial. The problem looks like "Dot Crawl", but that shouldn't happen with S-Video right?



How certain are you that the comb filter in your tuner box is good? It could be a that, or as the previous poster stated, it could have been encoded into the video. Also as the saturation levels go up, the tendency to have chroma bleed goes up as well.

Is your goal to capture commercials? If you are happy with the results of the captured program, why bother yourself with the commercials?


T

[RSVP]

How certain are you that the comb filter in your tuner box is good?


Not certain at all. It's a Scientific Atlanta Explorer 2000 (fairly old).


The cable provider in my area sends out both analog and pure digital channels to the box.

The problem is definitely more pronounced on the analog channels (I've yet to see the same commercials/other sources on the digital side though, for an apples-to-apples comparison).





Is your goal to capture commercials? If you are happy with the results of the captured program, why bother yourself with the commercials?

Not out to capture commercials, those shots were just the most convenient ones I had at the time.


The problem definitely happens on both commercials and programs.



Are there any specific tests I could try with the saturation level?

[tedkunich]

Not certain at all. It's a Scientific Atlanta Explorer 2000 (fairly old).


The cable provider in my area sends out both analog and pure digital channels to the box.

The problem is definitely more pronounced on the analog channels (I've yet to see the same commercials/other sources on the digital side though, for an apples-to-apples comparison).






Not out to capture commercials, those shots were just the most convenient ones I had at the time.


The problem definitely happens on both commercials and programs.



Are there any specific tests I could try with the saturation level?

Unfortunately I do not think your are going to be able to come up with a "golden" setting that works on everything - there are just too many variables at play here: cable co, cable box, your capture card, channel, and the production company making the programming. I would suggest that you get a calibrated baseline for your capture rig by using your DVD player, Dscaler, and either DVD Essentials or Avia. Dscaler has a automatic calibration mode that will proberly adjust your levels and saturation level approriate for that DVD player and your capture card. You can copy the settings down for future reference. Don't be surprised if it appears flat - most people are used to seeing saturation and levels extremely jacked up and don't realize it. Once you have your baseline, you can then do some minor tweaks to your settings to compensate for a particular program/channel.


Oh, one other thing... it looks like your cable box may have a poor comb filter - you may want to try capturing with the composite cable vs. Svid and see if that helps with the dot crawl.


T

[jmac698]

That is definitely dot crawl. I would look for a cable which intermittently connected the supposedly separate luma and chroma signals. So try wiggling the cable or trying another one for a while.

Second, on both analog (obviously) and digital channels you can find some material which was composite originally. So even though you have an svideo or even firewire connection it won't make any difference. This is very annoying because my TV (and probably all), only use the comb filter processing on the composite inputs.

You can clean this up in your caps with the appropriate filter, for example if you can watch with dscaler (it has a directshow mode so you can always use it). Under filter, temporal comb.
http://www.doom9.org/index.html?/capture/chroma_artefacts.html
You need Guavacomb.

You can also use a composite connection to your cap card. Strangely, this would *improve* the quality, because of this problem, as your card probably has some excellent comb filters.