Linked by Thom Holwerda on Fri 24th Feb 2012 21:59 UTC
Multimedia, AV An interesting anecdote at MinimalMac about television being broken. The author's young daughter, who is growing up in a Netflix/Hulu/iTunes/etc. household, was confronted with actual TV for the first time, and wonders why she can't pick what to watch, why the shows are being interrupted all the time, and so on. Clearly - TV is broken.
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RE[3]: DVD Quality
by ilovebeer on Sun 26th Feb 2012 07:50 UTC in reply to "RE[2]: DVD Quality"
ilovebeer
Member since:
2011-08-08

Upscaling (and for that matter, transcoding anything to higher bitrates) will _never_ improve quality. The absolute best you can hope for is the same as your source.

Sorry, but that is simply not true in all cases. Upscaling (as the OP was using the term) has nothing at all to do with bitrate or improving the quality of the source material - it is about preparing it as best as possible for the screen it will be presented on.

Any time you have movement, bitrate becomes a factor (as done a number of other things). The OP suggested there's no difference between his source material, and his upscaled version. The only problem is that it's not possible. Quality can be presented in two ways -- as interpreted by the viewer, and mathematically. Maybe the OP really can't see any difference due to poor eyesight. But, mathematically the statement is false.

Most older HD TVs simply enlarge the lower resolution image of a DVD to fit the screen size by performing simple block scaling. This works but generally looks horrible, and the larger the screen the worse it looks.

This is correct.

TVs or DVD players that perform "upscaling" are using much more sophisticated interpolation algorithms to perform the scaling, as well as usually performing motion compensation to correct issues that arise during scene transitions, etc.

Some do, most don't. Regardless of the scaling method used, there are none which don't degrade or malform the image in some way. The absolute best scalers available are not immune to this.

Also, if you are preparing DVD material for display on a 1080p screen, transcoding it to 1080p resolution can improve the picture quality relative to the original DVD - it depends on the TV it will be displayed on.

The above is both a common misconception, and complete rubbish. There is no magic algorithm by which otherwise absent quality appears out of thin air. Some people fool themselves into believing what you've suggested, but as I've stated earlier the math always proves false.

It isn't a matter of bitrate, it is simply compensating for poor scaling circuitry in the TV. Granted, most current HDTVs have very good scaling performance - but if you have an older one the difference can be quite dramatic.

We're not talking about a single still frame so yes, bitrate is most certainly one of many determining factors in quality here. It's not as if any of this is a secret. No two people see the exact same image. No two people see exactly the same colors. As you can guess the differences can greatly vary. When someone says there's no visible difference, they should acknowledge it's from their perspective only.

Reply Parent Score: 3

RE[4]: DVD Quality
by galvanash on Sun 26th Feb 2012 16:17 in reply to "RE[3]: DVD Quality"
galvanash Member since:
2006-01-25

"Also, if you are preparing DVD material for display on a 1080p screen, transcoding it to 1080p resolution can improve the picture quality relative to the original DVD - it depends on the TV it will be displayed on.

The above is both a common misconception, and complete rubbish. There is no magic algorithm by which otherwise absent quality appears out of thin air. Some people fool themselves into believing what you've suggested, but as I've stated earlier the math always proves false.
"

If you play a 720x480 DVD back on a 1080p LCD/Plasma HDTV, it WILL be resized/upscaled to 1920x1080 whether you like it or not. Again, it is not about improving quality, it is about avoiding image degradation in the TV's scaling circuitry.

Your TV can do the scaling, or maybe you have an upconverting DVD player, in which case it will do the scaling - but something will be scaling the video - LCDs and Plasmas are fixed resolution devices.

If you TV has shitty scaling circuitry the quality of the image on your TV will be degraded badly ( blocking artifacts, tearing during scene changes, ringing, etc.). Transcoding the video prior to sending it to your TV using a a high quality interpolation routine (Lanczos4 or something similar) will improve the quality of the image on your TV, often dramatically. Yes, it does degrade the image relative to the source in a mathematical sense (badly at that), but on YOUR TV with shitty scaling circuitry it will look better.

In other words it is stupid to compare the quality of an 1080p transcode of a DVD to the original source material in a purely mathematical sense, because you never in fact get to see the original on an HDTV - it is always resized.

What you are comparing is the quality of a realtime scaling routine in the TV/DVD players circuitry to the scaling routine used during transcoding (which can be much more complex/accurate because it doesn't have to work in realtime). If you TV has bad scaling performance the transcode will almost certainly look better on your TV.

This is exactly what I said before, it is absolutely accurate, and I have no idea how you can claim otherwise.

Reply Parent Score: 1

RE[5]: DVD Quality
by ilovebeer on Sun 26th Feb 2012 16:52 in reply to "RE[4]: DVD Quality"
ilovebeer Member since:
2011-08-08

If you play a 720x480 DVD back on a 1080p LCD/Plasma HDTV, it WILL be resized/upscaled to 1920x1080 whether you like it or not. Again, it is not about improving quality, it is about avoiding image degradation in the TV's scaling circuitry.

It seems that you and my high-end Panasonic plasma tv are in disagreement about this. For that matter, no hdtv I have ever owned forces scaling. In all of them, scaling was optional. Do you even own an hdtv?

Your TV can do the scaling, or maybe you have an upconverting DVD player, in which case it will do the scaling - but something will be scaling the video - LCDs and Plasmas are fixed resolution devices.

They are fixed-pixel displays. However, you are wrong by assuming that this means all non 1920x1080 images are scaled up to 1920x1080. Apparently you don't understand that no scaling in required to display x 544x480 image on a 1080p display. There are two surfaces that are combined to create the final image -- the video surface, and non-video surface. The non-video surface is always the native resolution while the video surface can be anything up to the native resolution. Scaling the video surface is optional in every 1080p tv I've seen or owned.

If you TV has shitty scaling circuitry the quality of the image on your TV will be degraded badly ( blocking artifacts, tearing during scene changes, ringing, etc.). Transcoding the video prior to sending it to your TV using a a high quality interpolation routine (Lanczos4 or something similar) will improve the quality of the image on your TV, often dramatically. Yes, it does degrade the image relative to the source in a mathematical sense (badly at that), but on YOUR TV with shitty scaling circuitry it will look better.

You're confused as to what this conversation is about and what the OP said. We are NOT talking about comparing real-time upscaled material vs. a pre-processed version. Aside of that, you still have a few things wrong. Image degredation/malformation is UNAVOIDABLE regardless of your output device. As I've already said, there is no such thing as a magical algorithm. And, I don't own crap tv's.

In other words it is stupid to compare the quality of an 1080p transcode of a DVD to the original source material in a purely mathematical sense, because you never in fact get to see the original on an HDTV - it is always resized.

You are wrong as already explained above. (see reference to surfaces)

What you are comparing is the quality of a realtime scaling routine in the TV/DVD players circuitry to the scaling routine used during transcoding (which can be much more complex/accurate because it doesn't have to work in realtime). If you TV has bad scaling performance the transcode will almost certainly look better on your TV.

This is exactly what I said before, it is absolutely accurate, and I have no idea how you can claim otherwise.

No kidding most real-time internal tv scalers can be outperformed by more advanced software counterparts. But we aren't even talking about that so, ....

Reply Parent Score: 2

RE[4]: DVD Quality
by lucas_maximus on Mon 27th Feb 2012 12:02 in reply to "RE[3]: DVD Quality"
lucas_maximus Member since:
2009-08-18

The OP suggested there's no difference between his source material, and his upscaled version.


No I didn't, I said I couldn't see the difference, this is a massive difference from there actually being a difference.

Reply Parent Score: 2

RE[5]: DVD Quality
by galvanash on Mon 27th Feb 2012 17:06 in reply to "RE[4]: DVD Quality"
galvanash Member since:
2006-01-25

Just ignore him. I know exactly what you meant. He's obviously just a troll.

Reply Parent Score: 2