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Discussion Starter · #1 ·
For widescreen movies, my Sony progressive scan player (model# DVP-NS55P) always slightly zooms in and/or cuts off the sides of the image relative to the image I see using the DVD-ROM drive on my computer. Movies shot at a ratio of 1.66:1 or 1.85:1 always fill the entire 16x9 frame when they should have small black bars at the sides, or top and bottom, respectively, while Cinemascope movies always lose some information at the sides. This is clearly a problem with the player as I see the same results on both my Sony WEGA and my LCD TV. I'm wondering which upconverting players - if any - are free of this overscan/zooming problem. I'd sure hate to waste time and money on a PS3 or Sony upconverter if they do the same thing.
 

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Quote:
Originally Posted by Mike999 /forum/post/14168092


I'm wondering which upconverting players - if any - are free of this overscan/zooming problem.

Many current players do not have underscan or overscan, but I have not kept track of which ones. You'll have to check specific player test reports. I know the current Oppos are OK.


Note that it is common for displays to treat standard definition and high definition signals differently in this regard. They will overscan standard definition more agressively. I'm guessing this is because they presume it is an old-style broadcast source which often has garbage at the edges which people don't like to see. That's not optimal for a DVD source.


EDIT: For looking at this, it is good to have a calibration disc with alignment/overscan patterns so you can actually measure the amount of overscan. I use the GetGray disc: http://www.calibrate.tv/


-Bill
 

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Discussion Starter · #5 ·
Thanks for the info, Bill.


Based on what I've learned from the ht-hifi site, there's really no way to tell how much a namebrand player will crop the image. Of course Oppos don't crop, but those are out of my price range, unfortunately.
 

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Correct me if I'm off base, but maybe what's causing some confusion here is the difference in behavior between LCD computer monitors, which have no overscan at all, versus TVs (both HD and SD), which typically overscan/crop a total of about 5-10% of the image in either direction.


If there is any cropping occuring in the DVD player, it's usually an infinitesimal amount (ie just a matter of a few pixels). Your concerns about major cropping occuring in recent major-label upconverting DVD players, etc. is I think largely unfounded.


Overscan occurs in the display, not in the player.


Both SD and HD CRT-TVs typically overscan about 5%, and most LCD-TVs also overscan both SD and HD video sources (including HDMI sources). Even 1080p TVs will usually overscan by default, though many include 1:1 stretch modes that will map 1080i/p video sources pixel-for-pixel directly to the screen with no cropping, or "justified" modes that will scale/map other resolutions (720p and sometimes also 480i/p) to fit the screen with no overscan/cropping. These justified/stretch-to-fit and 1:1 modes really only became popular since the advent of 1080p HDTVs though, so they are a relatively recent phenomena in home video. And many older and "720p/768p" TVs may not include them.


One other possibility is that the player is not configured correctly. For example, if you're getting an excessive amount of cropping (beyond the normal overscan that occurs in the display) off the sides of some widescreen DVDs, this could be because the player is set to pan & scan mode.


EDIT: One other caveat to the above. If you're using the RGB computer input on your LCD-TV, chances are you will NOT see any overscanning on that. The TV will only apply overscan to the regular video inputs, namely Composite, SVHS, Component/YPbPr & HDMI.
 

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Quote:
Originally Posted by ADU /forum/post/0


Overscan occurs in the display, not in the player.

The one "exception" to this rule is the 4:3 "pillarbox" mode on HDMI DVD players, which will frequently crop about 5-10% off the sides of 4:3 video image to simulate the effect of overscan... in addition to scaling/pillarboxing the 4:3 DVDs so they display correctly on a 16:9 HDTV screen .
 

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Discussion Starter · #8 ·

Quote:
Originally Posted by ADU /forum/post/14184126


Correct me if I'm off base, but maybe what's causing some confusion here is the difference in behavior between LCD computer monitors, which have no overscan at all, versus TVs (both HD and SD), which typically overscan/crop video images between 5-10%.

I guess I am confused, because I don't see any cropping when my LCD is displaying cable programs. In fact, I often see video junk at the sides of the screen, especially on SD channels. This led me to believe that the cropping I see with DVDs is due to the player and not the TV.


As I mentioned, the same amount of cropping occurs when I use this DVD player with my tube TV, but you're right that it's way more than just 2 or 3 pixels, so maybe it could be that both of my TVs just happen to have an equal amount of overscan. It seems absurd though that a digital TV would crop information from a 480p source.
 

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Quote:
I guess I am confused, because I don't see any cropping when my LCD is displaying cable programs. In fact, I often see video junk at the sides of the screen, especially on SD channels. This led me to believe that the cropping I see with DVDs is due to the player and not the TV.

It sounds like the zoom/stretch modes on the TV could be configured differently for your DVD player and cable inputs.


Another possibility is that your cable STB could be set to output everything at 720p or 1080i. If that's the case, then the STB may be pillarboxing the SD channels, without doing any cropping on the sides of the image. IOW, the STB is more in control of what you see on the SD channels when it's set to output everything in HD.


With the 480i/p input from your DVD player though, the TV controls what you see. And the TV will probably try to overscan (or slightly crop) the image, whether it's displaying a 16:9 widescreen DVD or pillarboxing a 4:3 fullscreen DVD. Without knowing all the exact details of your setup, it's hard to say.


Bill's suggestion of a calibration disc might be worth considering. In addition to GetGray, there are other options, such as DVE and AVIA. In lieu of this, there's also the THX Optimizer included in the extras on many THX-mastered DVDs, such as the Star Wars discs, which has a couple aspect ratio tests that may also give a better idea what's going on. The 4:3 and 16:9 aspect ratio THX Optimizer tests have two bounding boxes surrounding the circles. The inner/smaller box is the "safe-title" area, while the outer box is "safe-action". If you can see both boxes on your TVs, then you're doing pretty well. However, it would not be unusual for the outer box to be cropped on some TVs (especially SDTVs) by the overscan. The border around the safe-action area is about 5% on all sides of the image, while the safe-title area excludes about 10% on all sides.


Make sure the player is configured appropriately for each display as well. Here are 3 typical scenarios for a standard progressive player (HDMI upconverting players work a little different)...


1) If the player is connected to a 16:9 HDTV (such as the VX32L), set the SCREEN SETUP/TV TYPE to 16:9, and control the aspect of 4:3 content using the different stretch/zoom modes on the HDTV.


2) If the player is connected to a newer 4:3 480i CRT (SDTV) with a 16:9 V-compression feature (ie it vertically compresses the raster when encountering 16:9 content), you'll most likely want the TV TYPE set to 16:9 as well.


3) If the player is connected to an older 4:3 480i CRT without the 16:9 V-compression feature, then you'll most likely want the TV TYPE set to one of the 4:3 modes (unless you like squished images). With the 4:3 LETTERBOX mode, the player will automatically scale 16:9 anamorphic widescreen DVDs to the correct aspect ratio by adding (or increasing) the black bars on the top and bottom of the image. With the 4:3 PAN & SCAN mode, the player will attempt to crop off the sides of 16:9 widescreen DVDs rather than adding/increasing black bars on top/bottom. Most 16:9 DVDs will not permit this cropping however, and simply revert to letterboxed display.
Quote:
It seems absurd though that a digital TV would crop information from a 480p source.

Absurd maybe, but usually true.
 

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Discussion Starter · #10 ·

Quote:
Originally Posted by ADU /forum/post/14187422


Another possibility is that your cable STB could be set to output everything at 720p or 1080i. And the TV is removing the overscan (ie doing a stretch-to-fit) on the cable signal because it's in HD, but continuing to overscan the 480i/p SD signal from your DVD player.

I have a Comcast HD box set to 480i override, which means that for SD channels a 480i signal is sent to the TV. I tried using an HDMI cable with this box but it wouldn't allow 480i override and the 720p and 1080i modes (which I would assume means the box itself does a 480i->720p or 1080i upconversion) looked very grainy even with the sharpness turned all the way down to zero.

Quote:
In lieu of this, there's also the THX Optimizer included in the extras on many THX-mastered DVDs, such as the Star Wars discs, which has a couple aspect ratio tests that may also give some better idea what's going on.

I have discs with the THX Optimizer, so maybe I should give this a try and report back.

Quote:
1) If the player is connected to a 16:9 HDTV (such as the VX32L), set the SCREEN SETUP/TV TYPE to 16:9, and control the aspect of 4:3 content using the different stretch/zoom modes on the HDTV.

For anamorphic DVDs, I set the player to 16:9 mode, and the TV to WIDE, which according to the Vizio manual is the correct setting for 16:9 discs. Curiously, with the player set to 4:3 LETTERBOX or PAN AND SCAN and the TV set to WIDE, the frame that appears on the screen appears to be exactly the same as with the 16:9 setting, but the image quality isn't quite as good.


For 4:3 discs, I have to reset the player to 4:3 LETTERBOX, since setting the TV TYPE to 16:9 results in an image that appears to have a 3:2 aspect ratio.

Quote:
2) If the player is connected to a newer 4:3 480i CRT (SDTV) with a 16:9 V-compression feature (ie it vertically compresses the raster when encountering 16:9 content), you'll most likely want the TV TYPE set to 16:9 as well.

Both the 16:9 and 4:3 modes on my Sony WEGA crop about as much of the frame as my LCD screen. Again, watching DVDs on my computer, I'm amazed at how much information is being lost due to overscan. With Cinemascope films, there are often scenes where people standing at the edges of the frame are totally gone.
 

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Quote:
Originally Posted by Mike999 /forum/post/0


I have a Comcast HD box set to 480i override, which means that for SD channels a 480i signal is sent to the TV.

If both DVD player and cable-box are sending SD (480i/p) signals to the LCD-TV, then maybe the zoom/stretch modes on the TV are configured differently for the two inputs. You might want to experiment with the other zoom/stretch modes on the LCD-TV to see if a different mode eliminates the overscan on the DVD player. (Or maybe there's some kind of on/off control for overscan in the TV's other settings.)
Quote:
For 4:3 discs, I have to reset the player to 4:3 LETTERBOX, since setting the TV TYPE to 16:9 results in an image that appears to have a 3:2 aspect ratio.

This shouldn't really be necessary. You should be able to leave the DVD player set to 16:9 TV TYPE for the LCD-TV, and just control the display of 4:3 DVDs using the stretch/zoom modes on the TV. (The THX Optimizer AR tests should assist with that.)
Quote:
watching DVDs on my computer, I'm amazed at how much information is being lost due to overscan. With Cinemascope films, there are often scenes where people standing at the edges of the frame are totally gone.

If you don't want any extra cropping on the sides of widescreen DVDs on the WEGA, then definitely avoid the 4:3 PAN SCAN TV TYPE on the player (though most DVDs will display exactly the same as with the 4:3 LETTERBOX TV TYPE). If the WEGA has 16:9 V-compression, then the 16:9 TV TYPE will probably give the best results, because the player will not have to perform any scaling on the DVDs to fit them to the TV.


I've seen exactly the kind of thing you're referring to above on both my SD-CRT and Sony HD-CRT though (before tweaking the overscan on it).
Quote:
I tried using an HDMI cable with this box but it wouldn't allow 480i override and the 720p and 1080i modes (which I would assume means the box itself does a 480i->720p or 1080i upconversion) looked very grainy even with the sharpness turned all the way down to zero.

I can understand some of your reluctance re upconverting players after reading this. You might possibly be surprised by the quality you'd get with even a couple of the relatively inexpensive HDMI players (or not). The results might be a little better if the VX32L accepted a 1080p input though. If you're holding off for a BD player with good upconversion (which is a bit hard to find right now), or one of Toshiba's "super-upconversion" players, that's certainly understandable as well.


IAC, I did some tests to see how bad the cropping is on a couple HDMI players at 1080p using both DVE and some of my own patterns (since the overscan tests in DVE aren't that great for 4:3 content), and as far as I can see, there's little or no cropping at all on the Sony 77H and 700H on both 16:9 or 4:3 DVDs. Maybe a half pixel is cropped off the right side of 4:3 DVDs with the player's 4:3 pillarboxing enabled. But otherwise, I can see all the pixels at the edges of my 720x480 resolution patterns, after they've been scaled to 1080p.


The Pioneer 410V crops about one and a half pixels off the bottom edge of the 720x480 patterns on both 16:9 and 4:3 DVDs. And it crops about 2.5% of the image off each side of 4:3 DVDs when the 4:3 pillarboxing is enabled on the player (which isn't unusual). A small amount of cropping on the sides of 4:3 content isn't necessarily a bad thing though, because it can hide the schmutz that sometimes appears along the edges of poorly-authored DVDs. (The Pioneer 410V is still my pick between these players at the moment btw.)
 

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Discussion Starter · #12 ·

Quote:
Originally Posted by ADU /forum/post/14191590


You might want to experiment with the other zoom/stretch modes on the LCD-TV to see if a different mode eliminates the overscan on the DVD player. (Or maybe there's some kind of on/off control for overscan in the TV's other settings.)

Unfortunately, the VX32L is a relatively low end model and only has WIDE, 4:3, and three *fill* modes for 4:3 material (CROP, STRETCH, and PANORAMIC).


As promised, I tried the THX Optimizer, and according to the 16:9 test, neither the VX32L nor the WEGA display any overscan problems, which is strange, since this test is run using the DVD player. Both of the boxes fit well within the limits of both screens, with the WEGA exhibiting a slighter tighter fit and a small shift to the left. These results indicate to me that either the test is wrong or else the TVs don't overscan this particular image for some reason.

Quote:
The results might be a little better if the VX32L accepted a 1080p input though. If you're holding off for a BD player with good upconversion (which is a bit hard to find right now), or one of Toshiba's "super-upconversion" players, that's certainly understandable as well.

I'm definitely going to buy a Blu-Ray player at some point, but the PS3 seems to be the best option and - according to some people - its upconversion isn't nearly as good as that of other players.


For now, all I'm looking for is a reasonably-priced upconverter which can provide better image quality and less overscan. It would appear that the three players you tested - the Sony 77H, 700H, and Pioneer 410V - are the three best players in my price range. The Pioneer seems to get the best reviews of the three, but which do you personally think is the best overall player?
 

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Quote:
Originally Posted by Mike999 /forum/post/0


As promised, I tried the THX Optimizer, and according to the 16:9 test, neither the VX32L nor the WEGA display any overscan problems, which is strange, since this test is run using the DVD player. Both of the boxes fit well within the limits of both screens, with the WEGA exhibiting a slighter tighter fit and a small shift to the left. These results indicate to me that either the test is wrong or else the TVs don't overscan this particular image for some reason.

Maybe I wasn't precisely clear on what the boxes represent in the THX Aspect Ratio tests. If your TV was cropping the image right at the edges of the larger box (ie the "safe-action" boundary), that would represent 5% overscan. If there's some space between the safe-action box and the edge of the TV screen, then you know that the overscan on your TV is less than 5%. (Basically anything less than 5% overscan is generally considered "acceptable".)


If you look at the THX patterns on a computer where you can see the entire image without any overscan, then you'll probably get a somewhat better idea just how much space there is between the safe-action box (5% overscan) and the edge of the image, which would represent 0% overscan. Then you should have a slightly better idea how much of the pattern your TVs are actually cropping off, and whether they're in the 1-2% or 3-4% range of overscan. This is just to get a rough estimate of what's going on though. For a more accurate reading, you'll need some better patterns, something like this: Attachment 114446 (not one of my better creations, but hopefully it illustrates what I'm talking about).


(NOTE: You can't simply burn the above JPEG to a CD or DVD, and then expect to get a reliable result from it on your player, because many players will add an add'l border around JPEGs & photos to prevent the overscan on most TVs from obscuring the edges of the picture. Or they will scale the JPEGs in one dimension in order to display them in the correct shape/aspect ratio. For an image like this to do anything useful, it has to be properly converted to the DVD-Video format. So it's being posted here just for illustration purposes.)


The safe-action box in the THX patterns is pretty close to an accurate 5% though. So it sounds like things are working pretty much as they should (and your TVs are at least within the 5% spec).

Edit: Revised image to make things a bit clearer, and a bit more accurate.
 

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Apologies in advance if this gets too technical for some of the newbs, but while on the subject of overscan/cropping thought I'd mention that several of the tests (including the Overscan Test) on my 2003 component video edition of DVE appear to have some of the top and bottom missing from the pattern. (This is visible on a PC as well, so ~95% sure it's not a player-related problem, and would guess it's something that's come up in other AVS calibration discussions.)


Only a few pixels appear to be missing along the top and bottom, but perhaps enough to make patterns like the overscan test at Chapter 12/Title 17 less than totally reliable for accurately gauging the vertical overscan on some TVs and potential cropping on DVD players.


The DVE overscan test also does not work with player-based pillarboxing on HDMI upconverting players (such as the Sony 77H/700H and Pio 410V), for displaying 4:3 DVDs at 720p/1080i/p.


If you're not overly picky about this stuff, then it should still be somewhat useful. (If you only pay attention to the sides of the overscan pattern for example, then it works fine for 16:9 tests and gauging cropping/overscan of TV-based pillarboxing at 480i/p. And there are some other 1.33AR/4:3 patterns that work okay with the pillarboxing on HDMI players.) But because of these issues, it probably would not be my first tool of choice for accurately assessing some of the cropping and overscan issues discussed here. (And might perhaps be one reason for exploring other similar tools like GetGray.)


DVE is certainly handy for alot of other things though. And perhaps some changes were made to more recent editions to make these kind of jobs go more smoothly.
 
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