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AVIA IRE level Errors?  

post #1 of 76
Thread Starter 
I was having a chat with an acquaintance regarding my PJ calibration efforts the other night when he told me something interesting about the AVIA IRE screens. He said that they are not in line with the actual signal level. 0 is 0 and 100 is 100, but everything in between is a bit off. i.e. IRE30 is something like 24%, IRE40 is around 35%....

Has anyone else ever run into this? And if this is the case (I have no reason to doubt the person that told me this, as he has probably forgotten more about video than I will ever know) then do I calibrate to the signal values he gave me, or use the labeled IRE numbers?

TIA,
RG
post #2 of 76
I noticed this with SMART. This is because the percentage of stimulus, i.e. the signal level, is not equal to the nominal IRE level. For a DVD playe with the black level at IRE 7.5, it is easy to understand that the percentage of stimulus for the IRE 10 window will be eroughly 2.5 percent above black, etc.. The same actually applies to DVD players set up for a black levels of IRE 0, the percentage of stimulus is again roughly 2.5% above black. Thus it is the percent stimulus that needs to be taken into consideration when plotting gamma tracking rather than the nominal IRE levels.
post #3 of 76
The labeling of the signal levels in Avia assumes and is correct if the DVD player has normal NTSC setup of 7.5 IRE. This is not an error but a consequence of correctly labeling the patterns for the IRE level that should be output on a player with proper North American setup. Black of such a player is output at 7.5 IRE and white is at 100 IRE. However, one shouldn't confuse IRE with percentage of signal level. They aren't the same numerically.

The signals labeled as 7.5 IRE is output as 0% (black)
The signal labeled as 100 IRE is output as 100% (white)

You can calculate the actual percentage output for each level whether the setup is 0 or 7.5 IRE as....

Output percentage = (labeled IRE - 7.5) *(100/92.5)

So the following are IRE label and the corresponding %output

7.5 IRE = 0.0%
10 IRE = 2.7%
20 IRE = 13.5%
30 IRE = 24.3%
40 IRE = 35.1%
50 IRE = 45.9%
60 IRE = 56.8%
70 IRE = 67.6%
80 IRE = 78.4%
90 IRE = 89.2%
100 IRE = 100.0%

Now you know more than your friend.
post #4 of 76
Thread Starter 
Guy,
If you check back on this thread then please clarify which one of these sets of numbers does the Gamma curve adhere to?

To try and put it more clearly, when taking data using the IRE fields: 10, 20, 30, etc... should I 'treat' those as 2.7, 13.5, 24.3, etc... with regards to the gamma curve?

If I understand Steve's answer correctly, then this would seem to be yes. I would like to be sure, though. Otherwise, I may be setting my levels way too high on the low end.

Thanks again,
RG
post #5 of 76
The numbers you should use are the percentages 2.7, 13.5, 24.3...

You are trying to plot input percentage vs light output to look at gamma.
post #6 of 76
Thread Starter 
Thanks, Guy!

RG
post #7 of 76
Steve,
Does this mean that the Smart III graph of Gamma -vs- IRE is wrong?
Dennis
post #8 of 76
The graphs that Steve produces offset the curve horizontally to take care of the issue. I'm pretty sure he already corrects for this difference between IRE and percent stimulus in Smart III.
post #9 of 76
SMART III does correct for this issue (always has), as Guy suggests.

Steve
post #10 of 76
Guy and Steve,
Thank you both for your responses.
Dennis
post #11 of 76
Guy,

What if you're using an HTPC with TT and scoping the output of the video card? I don't believe there is any setup for PC video, so is 0 IRE = 0% (or 0 mV) and 10 IRE = 10% (or 70 mV), etc.?

Thanks,
Peter
post #12 of 76
So what should I do if I have a player which plays both NTSC and PAL dvds?
Shall I change anything in SmartIII or in somewhere else?
Thank you
Paolo
post #13 of 76
Quote:
Originally posted by PeterAM

What if you're using an HTPC with TT and scoping the output of the video card? I don't believe there is any setup for PC video, so is 0 IRE = 0% (or 0 mV) and 10 IRE = 10% (or 70 mV), etc.?

Peter [/b]
That begs the circular argument going on in another thread. I'll try to clean up that mess, but most likely some people will remain confused.

1. I think we can safely assume people agree what a volt and millivolt are. For simplicity let's also assume that input and output impedances are 75 ohms and well matched so we don't have to correct for impedances.

2. IRE is well defined in terms of voltage with 140 IRE units in 1 volt. You can express electrical potential in IRE instead of volts if you know that fixed relationship. An IRE is 1/140 volt or approximately 7.142857142857142 mV. A common expectation in NTSC video signal that the positive 100/140 of a 1 volt peak to peak carries the image information, while the negative 40/140 is sync signal.

Black in North American NTSC with 7.5 IRE setup is at 7.5 IRE. 100% White in an image is at 100 IRE. That corresponds to

Black = 7.5 IRE * 1000 mV /140 IRE =~ 53.57 mV
White = 100 IRE * 1000 mV /140 IRE =~ 714.29 mV


If setup is zero as in the case of Japanese NTSC, then black is represented as 0 IRE but white is still represented as 100 IRE. That corresponds to

Black = 0 IRE * 1000 mV /140 IRE = 0 mV
White = 100 IRE * 1000 mV /140 IRE =~ 714.29 mV


This creates a problem for labeling of test signals on a DVD. The choice of which standard for representing black is chosen on a DVD player alters the output voltage (and IRE) of a signal. A test disc cannot set the DVD player to one standard to another and labeling correctly for one means the labels aren't correct for the other. I followed the most common North American NTSC convention and labeled the signals so the labels are correct if the DVD player outputs 7.5 IRE for black and 100 IRE for 100% white. This makes the labeling correct for most cases of NTSC output so labeled IRE matches output IRE.


Code:
Labeled Percent Output  Output  
IRE     Stim    IRE     mV
7.5     0.0     7.5     53.6
10      2.7     10.0    71.4
20      13.5    20.0    142.9
30      24.3    30.0    214.3
40      35.1    40.0    285.7
50      45.9    50.0    357.1
60      56.8    60.0    428.6
70      67.6    70.0    500.0
80      78.4    80.0    571.4
90      89.2    90.0    642.9
100     100.0   100.0   714.3


Players with a 0 IRE representation for black and 100 IRE for 100% white will output IRE levels that don't match the on disc labeling would do the following. Notice that the relationship between labeled IRE and percent stimulus remains the same as for players with 7.5 IRE setup. However, the output IRE and mV change.

Code:
Labeled Percent Output  Output  
IRE     Stim    IRE     mV
7.5     0.0     0.0     0.0
10      2.7     2.7     19.3
20      13.5    13.5    96.5
30      24.3    24.3    173.7
40      35.1    35.1    251.0
50      45.9    45.9    328.2
60      56.8    56.8    405.4
70      67.6    67.6    482.6
80      78.4    78.4    559.8
90      89.2    89.2    637.1
100     100.0   100.0   714.3
Notice also that the output IRE's match percentage signal if setup is zero and white is at 100 IRE. You can use the formula I gave earlier to do the calculations yourself.

Important take home message. The percent stimulus encoded by the signals on the test discs and the on labeling have a fixed relationship even if you change setup level. Black (labeled as 7.5 IRE) is supposed to be displayed as black. White (labeled as 100 IRE) is supposed to be displayed as white.


Lets get back to the original question...

is 0 IRE = 0% (or 0 mV) and 10 IRE = 10% (or 70 mV), etc.?

We already know that by definition, 1 IRE = 1000 mV/140 so by definition....

0 IRE = 0 * 1000/140 = 0 mV
10 IRE = 10 * 1000/140 =~ 71.4 mV
100 IRE = 100 * 1000/140 =~ 714.3 mV

Video card analog output signal levels such as for VGA aren't as rigorously defined as for NTSC video. Typical computer graphics place max white is about 0.7 volts and black at 0 volts. That would put the signal range as going from 0 IRE up to 98 IRE - not an exact match to make 100 IRE be max white so the convenience of using IRE to describe electrical potential falls apart. We're probably better off describing things in mV rather than IRE when it comes to computer video.

Computer RGB puts black at RGB 0,0,0 and absolute max white at 255,255,255. No blacker than black footroom nor whiter than white headroom are provided. The output is set up such that black RGB 0,0,0 corresponds to 0 mV and white RGB 255, 255, 255 is at 700 mV. Unfortunately, actual video material also requires footroom and headroom data in the signal to be represented or else image information is lost. This need was provided for by allocating the bottom and top of the digital signal range to permit "blacker than black" and "whiter and white." Digital video encodes a wider dynamic range that goes from blacker than black to whiter than white. Black is at digital 16 and white is at digital 235. Blacker than black data is allocated digital 1 to 15 and whiter than white is 236 to 254.

This creates a problem when it comes time to implement how digital video should be represented on a computer video card. Once could clip both ends of the digital signal range and then expand the remaining range to map black at RGB 0,0,0 and white at 255,255,255. This irretrievably clips video information and can create banding artifacts because a smaller range [16..235] is expanded to [0..255]. The value mapping isn't completely monotonic so banding can be induced. Another way to handle this would be to simply shift the digital data downward by 16 so no range rescaling is done, but this still cuts off blacker than black info and makes white on video much dimmer than white in computer video. The preferred solution for Media Center Edition PC's - computers specifically designed for multimedia use, is one that preserves video signal integrity over computer graphics. Black and white are kept at the values 16 and 235 and the MCE qualified displays are adjusted to properly display digital 16 as black and digital 235 as white. This avoids banding issues and displays video at full range. Computer RGB is less accurately displayed (unless it is in studio RGB with black = 16,16,16 and white = 235,235,235), but since the MCE's primary function is to provide high fidelity multimedia playback, the tradeoff is a reasonable one. Some older (esp. LCD panels) displays may lack the controls needed to adjust black level to make digital 16 true black. Displays with such limitations are not considered to be MCE compatible.

In HTPC's, the end user is free to make their own choices about how video signal levels are to be ranged and offset to fit within their video card output range. The degree of signal clipping and banding will vary depending on the user choices. The tradeoff between computer graphics and video graphics fidelity is certainly grounds for debate in HTPC's and no one right answer will satisfy all owners. For that reason it is not possible to state for HTPC's what mV is "correct" for black or white. It depends on the user goals and display capabilities. For MCE's the choice has already been set and both MCE and display manufacturers will very likely come to follow or allow for Microsoft's standard for the operating system. Black is at digital 16 and white is at digital 235.

If you really need to think of this in mV on an MCE....

Video Black = digital 16 = 16/255 * 700 mV = 43.9 mV
Video White = digital 235 = 235/255 * 700 mV = 645 mV

On such a system the Avia and Avia PRO 7.5 IRE labeled patterns would be at Video Black or 43.9 mV
and 100 IRE labeled patterns would be at Video White or 645 mV.

On a HTPC, your guess is as good as mine because the video signal scaling and offsets are not standarized. At any rate, I hope people adjust their HTPC and display COMBINATION to make black be displayed as black and white displayed as white.
post #14 of 76
Thread Starter 
Thanks for the comprehensive explanation, Guy. I believe this is what my friend was trying to explain to me the first time around and I just wasn't grasping it. I have since had another discussion with him and it makes alot more sense now.

This information begs the question though: unless you know that your display is already calibrated for 16-235, how can you know what your video card is putting out? This is especially problematic for DVI connections, which can't really be 'scoped'.

Based on what my friend has told me, my understanding is that I will need to use an external source of some sort to calibrate my display to these two points and then connect the HTPC to essentially calbrate it to the display and then proceed from there on the rest of the calibration.

RG
post #15 of 76
Guy,

Yes, thanks for the in-depth answer. It will take me a while to digest all of it. BTW, I'm amazed by this statement: "An IRE is 1/140 volt or approximately[emphasis added] 7.142857142857142 mV." I guess I need a new voltmeter if "approximately" is 15 places!

But I'm left a little confused after my first reading. If black and white are fixed by the display at no (ideally, at least) and maximum light output, either isn't blacker than black and whiter than white info lost or you don't truly have black or white no matter how you handle the level conversion?

Thanks again,
Peter
post #16 of 76
"That begs the circular argument going on in another thread."

I haven't had time to check the Forum much the last few days - which thread does this refer to?

Peter
post #17 of 76
Probably any of the Samsung threads in the DVD Hardware forum. :D
post #18 of 76
Or maybe the two linked in this post:

http://www.avsforum.com/avs-vb/showt...97#post4034797
post #19 of 76
Quote:
[i]
.... If black and white are fixed by the display at no (ideally, at least) and maximum light output, either isn't blacker than black and whiter than white info lost or you don't truly have black or white no matter how you handle the level conversion?
Peter [/b]
Ideally, the mastering process will place information that is intended to be black at digital 16 and material that is intended to be max white at digital 235. That is an admirable goal and one that should continue to be striven to help standardize material. Real life signals and mastering means that there continues to be some image information that ends up at slightly too high or too low an encoded level. There are a few reasons that blacker than black and whiter than white data should be preserved if possible in the playback system.

1. Some material may have black material encoded at too high or too low a level. If it is encoded too low, hard clipping of everything below digital 16 would irreversibly remove shadow details that could otherwise be visible if the brightness of the display is raised to "correct" the poor mastering.

2. Edge transitions include undershoot and overshoot. Scaling filters, particularly advanced ones with multi-taps optimized to reconstruct edge transitions sample data on either side of the transition, take into account the over and under-shoot. If an edge transition has its blacker than black or whiter than white components clipped, the reconstruction filter will be missing some of the needed data to properly reconstruct the edge transition. This can alter the sharpness of transitions and whether or not ringing becomes apparent.

3. Some display systems may employ spatial and temporal dithering systems to increase bit depth. Dithering results may be affected if one clips blacker than black image information. A near black pixel may be dithered to a different duty cycle if the surrounding pixels are clipped (all set to digital 16) vs left as intact image BTB detail with values that are not all digital 16. In such systems, "invisible" blacker than black details influence the brightness of dim image details. A dithering system may allow invisble BTB material to influence the appearance of dim details even though the BTB material is not itself visible. Indeed, even in analog display systems the non-instantaneous transition from pixel to pixel means that adjacent samples affect each other. The "invisible" portions of a signal can affect the visible portion.

The nominally invisible BTB and WTW range in video material contains information that can be useful when that information is the result of less than perfect mastering OR influences the mathematical processing for edge transitions and bit depth improvement. Even if mastering is perfect, the latter two processes mean that clipping away what would otherwise be "invisible" BTB and WTW can potentially influence the appearance of the "visible" portion of the video signal.

I myself was once too rigid an advocate of all BTB and WTW image details as being illegal and the result of poor mastering. It was over a period of time that Stacey Spears showed me that such a rigid stance had negative real life imaging consequences. I still believe that mastering of material should place black at digital 16 and white at digital 235 - just as per standards. The playback system, including display, needs to handle BTB and WTW to preserve all the nuances that are by human nature not always exactly right. The latter two processes also mean that even if we manage to overcome human inexactness, there are still reasons to preserve BTB and WTW image data.
post #20 of 76
Quote:
Originally posted by PeterAM
.....
I haven't had time to check the Forum much the last few days - which thread does this refer to?

Peter [/b]
Peter, it is the http://www.avsforum.com/avs-vb/showt...hreadid=416292 thread to which I refer. I discovered recently that I've been actively taking part in that spirited discussion without actually writing a single word in the thread. :eek:
post #21 of 76
Guy
Thanks for posting your comments and explanations on this subject. In the DVD Hardware forum, this topic comes up once an hour. Or is it once a week? It sure as hell seems like once an hour.

I posted a link to this thread and also the WWIII HT Video Convergence Confrontation :D going on in the Home Theater Computers forum in hopes that it will make the hours seem more... well, spread out. ;)
post #22 of 76
Quote:
Originally posted by Guy Kuo
Ideally, the mastering process will place information that is intended to be black at digital 16 and material that is intended to be max white at digital 235.
Guy,
I agree that "there are a few reasons that blacker than black and whiter than white data should be preserved if possible in the playback system".
But let us discuss when it is NOT necessary to preserve this data:

High Performance 1:1 Pixel Mapping
---------------------------------------------
1) By its very definition, for displays using 1:1 pixel mapping, no spatial and temporal dithering is allowed.

2) Following this logic, black values below 16 and above 235 are no longer of any use (except for as an aid in display calibration). (This assume that the display has been calibrated for a black of 16 and a peak of 235).

3) Isn't spatial and temporal dithering best done by the mastering engineer? As a goal, should not the end user display depict an image with no additional pixel distortion?

In summary the above white and below black information should be retained WHILE the image is being decoded/deinterlaced/scaled. But once all signal processing is complete the 1-15 and 236-255 information CAN be discarded with no ill effect when used with a 1:1 mapping display.

My ultimate goal is to send a 1920*1080p signal @60Hz to a 1:1 mapping 1920*1080 native resolution display.

Sloppy Mastering
----------------------
I disagree that the end user should be allowed to adjust for poorly mastered material. This is a band-aid solution as one can only do this after observing the materials technical deficiencies over time, then adjust the contrast and brightness (while other viewers are complaining), and then remembering to adjust back to the normal setting after viewing.
Sloppy mastering degrades the whole atmosphere of watching a movie. Be honest and ask ourselves, do your family members enjoy watching movies with you?

As a solution the mastering console needs a switch to remove the below black and above white information. Using this technique along with gray scale test signals would alert the mastering engineer to HIS errors. Isn't this a THE reason for the quality Thx mastering process?
I say educate the industry professionals, not the consumers. The fact is 99% of consumers have no inclination to correct mastering mistakes.
post #23 of 76
1:1 pixel mapping and BTW/WTW have nothing to do with each other.

Part of THX mastering is to ensure that all values from 1-254 make it through the entire process from telecine to final product. A product now fails THX certification if it does not preserve all of the original image information.

As an aside 235 is reference white, not peak white. 254 is peak white. This is very visible. You really can't put all information within 235 or you loose overall image contrast. The majority of image information is contained between 16 and 235. However, when you clip, you reduce color saturation and even shift from one color to another.

Dithering and noise shaping/error diffusion should be used during post production to reduce the 10-bit video down to 8-bits, but it is also used on display technologies like DLP. Both 3-chip and 1-chip consumer DLPs use dither since they don't really have enough bits. Plasma is doing something as well, but I don't know enough about that technology.

At the end of the day, we need at least 11-bits of data,ased on years of research. DVD and HD are both limited to 8-bits, which is from 1-254. If you limit the video from 16-235, you now have 7.7-bits instead of 8. we really can't afford to loose any bits. :)
post #24 of 76
So why is it when PCs convert video to the PC RGB colorspace (0-255) they throw away the info below 16 and above 235? Why isn't a 1:1 conversion possible, maintaining the full range of video information including BTB and WTW?

Dealing with this issue has been the biggest hassle of building my HTPC. I think I finally got it right by using the WinDVD 6 filters and VMR9 with Zoomplayer; BTB and WTW are both passed through, and using the brightness and contrast adjustments on my 12K via DVI has kept me from clipping anything.

Just wondering why studio RGB can't be directly mapped to PC RGB.
post #25 of 76
1:1 pixel mapping is simply feeding a digital display its native resolution so that there is no overscan and each source pixel lands directly on the displays output/dispay pixel.

Because PC RGB expands 16 and 235 to 0 and 255. You have to use Studio RGB to get what you are calling 1:1. Althoug it is not exactly 1:1.

YCbCr is a compression format, not really a color space as it is called. The value of Y along is not really relevant. It is when decompressed back into RGB that matters most. You can have a value that is at 20 in Y but when converted back to RGB that one of those three components can fall below 16.

Studio RGB and what we call PC RGB are simply two different conversions.

PCs are designed to be viewed in bright enviroments and have defined black at 0 and white at 255. Video is designed to be played back in low lit enviroments and has a different standard. There are a couple of solutions we are working on that solves the problem, but it will not happen in XP. The necessary plumbing is not there.

One point I believe many miss is that the PLUGE pattern is to be used in the lighting conditions you plan to watch TV. If you watch with the lights on, then you set until the BTB bars is gone. If you turn the lights off, you will notice you have a lot of below black visible. Also, CRTs are the display device used during post production. CRTs can't hold black at black as the APL goes up. (Even on the $50k displays used) So, some of that below black shows up and those overseeing the transfer expect the details to be visible.

Perhaps in the next 10-20 years those CRTs will be replaced with something more advanced. When this happens, then the playback displays will not have to emulate such old technology. Until then, even the latest displays have to emulate the shortcomings of CRT to make an accurate image.
post #26 of 76
Quote:
Originally posted by sspears
Also, CRTs are the display device used during post production. CRTs can't hold black at black as the APL goes up. (Even on the $50k displays used) So, some of that below black shows up and those overseeing the transfer expect the details to be visible.
I found this pretty interesting and I'm trying to figure out the reasons and implications. I understand how lower ANSI CR can wash out the image, but this seems to be a completely different effect. I hadn't heard that CRTs would actually raise the below blacks up in brighter scenes. I've been looking at and thinking about shadow detail quite a bit recently and what I perceive as people with heads on top of black holes (no detail) in some situations where people are wearing black shirts or tuxedos in mixed scenes. I figured that much of this was the washout effect from less than perfect ANSI CR. It seems from what you are saying that when calibrated properly the CRTs will actually raise up what they are putting out for dark pixels in bright scenes even disregarding the washout from other pixels. This would seem to have the effect of helping shadow detail and if digitals don't do this, then they could end up with less shadow detail than was meant to be displayed. Very interesting.

--Darin
post #27 of 76
Darin, what Stacey and Don are saying is this. The light output on CRT's for "black" drifts up slightly during dark scenes. This happens during viewing on the mastering CRT display and if the operator compensates for this to make the image look correct on his reference CRT display, the resultant encoded video ends up with the opposite "error." The level encoded for dark details ends up higher in brighter scenes and dimmer in dark scenes. CRT displays tend to have the this black level drift behavior so upon playback the errors cancel and you end up with a good approximation of what the mastering engineer saw. Digital displays don't share this common CRT black level drift with APL so they don't exactly mirror what happens on the mastering display and the image's black level doesn't quite end up at the right place for all scenes even though the display is being "rock solid." There is an existing legacy for which digital displays must emulate or else they don't reproduce the same image as expected.
post #28 of 76
Quote:
Originally posted by sspears
1:1 pixel mapping is simply feeding a digital display its native resolution so that there is no overscan and each source pixel lands directly on the displays output/dispay pixel.
I get that. Sorry for the confusion. When I said "1:1", I meant why can't 0 in the video colorspace be directly mapped to 0 in the PC space. Nothing to do with 1:1 pixel mapping, which is unrelated.

So the reason is that 0 in video doesn't correspend to 0 in PC land in terms of luminance? I think I get it.

So, once and for all, what's the correct way to calibrate brightness and contrast on a digital display when using a PC and a renderer such as VMR9 that passes BTB and WTW? Right now, I have it calibrated so that the BTB bar in Avia Pro matches the black background, which also happens to be the exact point there is no dithering in the black background on my 12K. Is that correct?

I have contrast set so that all three bars are visible on the pluge pattern. On the individual red/green/blue pluge patterns, two bars are visible. Should I push it higher or let it be?
post #29 of 76
Darin: I just sent you a PM with Stacey saying pretty much the same thing that Guy just said, and this conversion stuff is one reason I hesitate to compare shadow details *too* much with you at this point, because the computer I'm using in the interim *is* clipping BTB and WTW stuff, which contributes to things being lost to "black" and just turning into black holes. And it makes my clouds look like paper cut-outs...

We'll see how things look when I'm done!

Guy(or others): are there any digitals or processing out there that takes this shifting into account? Or do they all just stay locked-in?
post #30 of 76
Quote:
So, once and for all, what's the correct way to calibrate brightness and contrast on a digital display when using a PC and a renderer such as VMR9 that passes BTB and WTW? Right now, I have it calibrated so that the BTB bar in Avia Pro matches the black background, which also happens to be the exact point there is no dithering in the black background on my 12K. Is that correct?
Sounds about correct, though I will mention something. To get the most out of your 12k, you really want to adjust gamma to be close to 2.5. (The gamma of the CRT) You may or may not have the tools to do this. Perhaps Darin can share his numbers. The downside is this may change with the hours on the builb, but you can alway go back to default.

I am using the Joe Kane / Samsung DLP. I actually have brightness up one click so that the dither is visible. I can't really see it from my seating position, but upclose you can't miss it. :) I have done this because of the floating black level.

It really is sad when new technology is held back because of legacy stuff. :)

Darin, do you still have the 3-chip with anamorphic lens? If so, I have that clip all ready to go. (at least I think I have it encoded correctly.)

Quote:
get that. Sorry for the confusion. When I said "1:1", I meant why can't 0 in the video colorspace be directly mapped to 0 in the PC space. Nothing to do with 1:1 pixel mapping, which is unrelated.
I was confused too when I first read as I am so used to 1:1 pixel mapping. :)

Again, there are solutions to the problem, but it will a while before they are implemented. It is a problem we have been working on for the last year.
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