Newbie Lumagen HDP questions

[NicolasB]

It's clearly going to take me a long time to get any idea how my new HDP scaler works.

I will therefore shamelessly ask the odd newbie question in this thread.

First question.... Suppose I'm feeding it an anamorphic PAL SD signal. I would like the output to be the picture scaled to exactly 1024x576, with that scaled image displayed letterboxed in a 1920x1080 picture with a black border filling the rest of the screen.

Can I do that? If so, how? And, if I'm doing this, can I get it to switch automatically between letterboxed 720x576 and letterboxed 1024x576 when I change the aspect ratio setting?

[Liam @ Prog AV]

If I understand you correctly, does your TV have a pixelixel mode where if it receives 1024x576 it will show it in the central part of the TV and add it's own bars? If so, create and output memory for that resolution in the Lumagen (e.g. OUT3) and then assign MEMC of the DVD input to this output. This would be global for PAL signals on that input though. But I guess the Lumagen would be rescaling the anamorphic signal to fit the output anyway. What you cannot tell it to do is output 1080p with the 576p bit within the frame.

Have you downloaded the basic setup guide? It has a few more cryptic clues in it as to how to setup ins and outs and pair them together etc.

[NicolasB]

Originally Posted by Liam @ Prog AV

If I understand you correctly, does your TV have a pixel : pixel mode where if it receives 1024x576 it will show it in the central part of the TV and add it's own bars?

No. It zooms everything to full screen (unless you use PAP mode, which doesn't allow single-pixel increments, and I also can't figure out how to control PAP overscan).

I was hoping I would be able to use the Lumagen to achieve this effect, but it sounds from what you're saying as though I can't.

[Liam @ Prog AV]

Apart from overscan and masking adjustments, the Lumagen does not allow resizing the active image size within the output window. I don't know of any VP that would give you that I'm afraid. I think you would be about the only person in the world that would want that feature LOL!!! Shame the TV won't do it, not many that do.

You can switch the scaling off (SCALE = OFF, and must be using a matching output resolution - great for 1080i to 1080p) but with the TV rescaling it's not going to give you what you are looking for.

[NicolasB]

Originally Posted by Liam @ Prog AV

Apart from overscan and masking adjustments, the Lumagen does not allow resizing the active image size within the output window. I don't know of any VP that would give you that I'm afraid.

According to this thread you can do it on a Crystalio.

Edit: isn't there a "shrink" command on the Lumagen? (Go here and scroll down a little). That sounds like it might be heading in the right direction. It says it's capable of eliminating overscan on digital displays.

[CrispyToast]

Originally Posted by Liam @ Prog AV

Have you downloaded the basic setup guide? It has a few more cryptic clues in it as to how to setup ins and outs and pair them together etc.

Which guide is this Liam?

Sorry found it.

[Liam @ Prog AV]

Sign up for the Lumagen forum. It's at the top in a sticky in the Vision support forum:

http://www.convergent-av.co.uk/forum/

Have never noticed that option in a Crystalio before, my mistake. Is it still there in the C-II models? Definitely nothing on the Lumagen though (just tried).

[NicolasB]

Been very busy lately, but had some more time to experiment with my HDP today. Lost looks absolutely dazzling with proper film-mode deinterlacing. On the other hand, the quality of deinterlaced SD video seems to be absolutely shocking - even my Sky HD box does a much better job. (Wondering if I've cocked something up, there! )

Questions:

1) I've done the EDID editing thing to get 576i out of my Sky HD box via HDMI. Is there any way I can get the Lumagen to pass through 576i to the television? (I've tried setting the output resolution to 576, but this just causes the scaler to crash).

2) There's a useful setting out->misc->shrink which almost does what I want in terms of getting 1024x576 letterboxed. It does actually allow you to display a smaller image letterboxed inside a larger one with black borders; but sadly the maximum number of pixels you can have between the outer edge of the display and the edge of the picture seems to be 255 (assuming that number is a pixel count). Is there any sneaky way to make that number larger?

Edit:

Changing the "Size" setting (out->res->size) also works. But, again, there's a limit to how small one can make it. You can make the horizontal size as small as you like, but the smallest the vertical size will change to is -43 (default value is +84) and obviously you have to maintain the right aspect ratio. Using a negative "Size" and the highest degree of "Shrink" together gives me a quite significant amount of letterboxing, but the resultant image is still quite a bit larger than 1024x576.

Is there any sneaky way of making the vertical Size setting smaller? Any chance Lumagen might extend the Size or Shrink range in a future firmware release?

[choddo2006]

Originally Posted by NicolasB

On the other hand, the quality of deinterlaced SD video seems to be absolutely shocking - even my Sky HD box does a much better job. (Wondering if I've cocked something up, there! )

You MUST have. A techwood plasma is better at it than the Sky box (probly)

As to your original question, I'm not sure why you would want to do what you're asking. Why would you want it shrunk down? And why do you think it would be letterboxed? Or do you mean bordered all the way round? Is this on a projector and you want to optically zoom it? Certainly the DVDO products let you underscan an SD analog signal before placing it in the output frame so that you can compensate for overscan as you described. I use it all the time. I don't know exactly when this happens in the pipeline, as you'd lose detail if it's done before it's scaled up so I hope it's done after scaling up but no idea how much difference it would make in reality.

Just reading the rest of your last post ...
edit: no, still not sure why you'd want to do it I imagine the DVDO products are also limited in how far you can underscan since it's only designed to compensate for maybe 5%-6%

[NicolasB]

Originally Posted by choddo2006

You MUST have. A techwood plasma is better at it than the Sky box (probly)

I don't think I have, actually. My television is better at deinterlacing SD video than my Sky box is, but even the Sky box seems to be better than the Lumagen. It's much worse at correctly distinguishing between film and video, of course.

It looks particularly bad viewing something like the horizontal scrolling text on BBC News 24: weird sort of sparkly effect around the letters, especially M's. I've got it set up to switch manually between "Film" and "Video" mode so I can compare the two, so it is definitely getting an interlaced signal, definitely applying Video deinterlacing (rather than Film) and it isn't even trying to detect whether the source is video or not, so I don't think there can be anything I've missed.

Originally Posted by choddo2006

As to your original question, I'm not sure why you would want to do what you're asking.

Previous experience tells me that you aren't going to understand why I want to even if I explain it. It would be like me trying to explain why some sort of food that you hate so much it makes you feel sick even thinking about it is actually really delicious: you may be able to acknowledge that other people's tastes are not the same as yours, but you'll never truly appreciate how anyone can possibly think it tastes nice.

It's simply that I don't always want the picture to be upscaled; I want it to be displayed as close to its original resolution as it can be without messing up the aspect ratio. I prefer an image that is small and sharp rather than one that is large but very soft.

Given a choice between this (a part of a 720x576 image that has been scaled to 1024x576):


and this (the same part of the same image but this time scaled to 1920x1080):


I think that the first one looks better. I know you don't agree. I know virtually no one else in the entire world agrees. I don't care.

It does actually depend on the quality of the image too. A good quality DVD transfer I can stand to watch upscaled to full screen, but the average Sky SD transmission I can't: the picture quality simply isn't good enough that it can stand being blown up that large (IMO).

Deficiencies in video mode deinterlacing also become almost invisible if you aren't vertically upscaling.

Originally Posted by choddo2006

And why do you think it would be letterboxed? Or do you mean bordered all the way round?

Yes, I meant bordered all round: the full SD picture displayed as a 1024x576 image with black borders padding it out to 1920x1080.

Originally Posted by choddo2006

I imagine the DVDO products are also limited in how far you can underscan since it's only designed to compensate for maybe 5%-6%

At the moment switching to a different model of scaler is beyond my financial capabilities; I just want to know if there's any way of doing what I want with the Lumagen. I can get frustratingly close, but not quite there.

[NicolasB]

Another question:

Is there any way to set the output mode to be INDEP for some inputs but AUTOIND for others?

[Liam @ Prog AV]

Third question - all you have to do is point MEMA and MEMC at the same OUTSEL option and you have exactly the same characteristic as a fixed output. Actually reading back, are you saying you would rather manually choose e.g. 24 or 60 for some inputs, but have others always do 50/60? You can get into using MEMB and MEMD, then for every input that AUTO gives you the right characteristic for you make MEMA and MEMB (and MEMC and MEMD) point at exactly the same OUTSEL in both cases. If you can describe exactly what you need I can help a bit better.

On your blanking quest I have an idea that will only work if your TV is gonna play ball. Of course if your TV just had a 1:1 mode this would be easier LOL!

Anyways, you should experiment with creating a custom resolution. HTOT and VTOT are the total value of pixels in the output, which are made up of a front and back porch, a sync width, and then an active area (i.e. the bit with the picture in). What you could try is manipulating the porch size and active size. So if for example your 1080p output is HTOT of about 2500 and the HACT is obviously 1920, you could try taking 896 out of the HACT and putting it into the porch instead. This creates a signal with massive blanking space, but exactly 1024 width of active pixels. Not a lot of displays will play ball though and might just chuck the signal back at you. You may need to experiment a LOT to find the magic number, and only find out it isn't there (like the weekend I lost trying to get 50Hz native on a Fuji).

[NicolasB]

I've just this minute figured out how to do my letterbox thing.

I had been thinking in terms of both the "Shrink" and the "Size" setting separately maintaining the correct aspect ratio. But actually I don't have to do that, because I can use one setting to correct the incorrect aspect ratio that would otherwise be created by the other one.

So, I set the Shrink to be Top: 252, Left: 255, Bottom: 252, Right: 255. Then set the size from the default (+150, +84) to (-236, +84) and I'm there.

This should even allow me to watch NTSC DVDs at 848x480 if I want to.

The only remaining question is whether the scaler is going directly from 720x576 to 1024x576, or whether it's internally scaling up and then back down again; does anyone know?

Originally Posted by Liam @ Prog AV

Third question - all you have to do is point MEMA and MEMC at the same OUTSEL option and you have exactly the same characteristic as a fixed output. Actually reading back, are you saying you would rather manually choose e.g. 24 or 60 for some inputs, but have others always do 50/60? You can get into using MEMB and MEMD, then for every input that AUTO gives you the right characteristic for you make MEMA and MEMB (and MEMC and MEMD) point at exactly the same OUTSEL in both cases. If you can describe exactly what you need I can help a bit better.

If I'm playing a DVD then that might either be 50Hz or 60Hz. It is therefore useful to use the AUTOIND setting for DVDs: if I'm playing a 60Hz disc then the Mem A and Mem B buttons switch between memories A and B, but if I'm playing a 50Hz disc then the A and B buttons switch between memories C and D instead. That means I've got two memories for 50Hz sources and two for 60Hz ones.

However, the output from my Sky HD Box is always 50Hz. I would like to be able to easily access all four memories when watching Sky. But at the moment, because I'm using the AUTOIND setting, I only have access to the C and D memories - the A and B are reserved for when I have a 60Hz input via DVI (which is never).

I could switch from AUTOIND to INDEP, which would give me access to four different memories when watching Sky, but if I do that then, when watching DVDs, it stops automatically switching output refresh rate (e.g. switching automatically between memories A and C) when I switch between 50Hz and 60Hz discs. (I could still switch manually from A to C, but that's annoying).

Is there any way I can have both automatic A/C and B/D switching for DVDs and also access all four memories when watching Sky? (This would effectively mean the out->mode setting being stored per-input rather than globally).

[timmorris]

Originally Posted by NicolasB

Is there any way I can have both automatic A/C and B/D switching for DVDs and also access all four memories when watching Sky? (This would effectively mean the out->mode setting being stored per-input rather than globally).

It's a global setting on the Vision series I'm afraid. You can do what you want with the Radiance as it has four indepedent memories for each combination of input resolution and refresh rate.

Best start saving!

Tim

[Liam @ Prog AV]

It's a global setting and I don't think there is much room to make many changes to this. It's something I've mentioned to Pat before which I think is why the Radiance has such a more comprehensive way of doing it.

So do I assume that you have a switch connected into the input that Sky HD is using?? Sometimes it is possible to mix and match sources in such a way that only certain memories will load, e.g. putting HD-DVD and Sky HD on the same input via a switch will mean Sky HD will only ever want 50Hz stuff and HD-DVD will only ever want 60.

If you can list every single source and what exactly you want it to do and to which display(s) I might be able to be a bit more precise. Or is it more a case that you want to make a large number of output profiles? I can't see that you want more than 1080p50, and then your custom 576p chopped profile. Might be worth posting in the Lumagen forum as a feature request though