Trying to achieve a artifact-free picture with XviD...

[vigi_lante]

I'm basically talking about animated stuff (anime, cartoon etc) captured from analog cable TV. Since it's a analog signal, the picture is not compressed, and despite the lower resolution and noise, the video quality can be considered better than DVD (mainly because, as I said before, the video is not compressed).

So, I think it's possible, with the right filters to remove all the noise (easier since it's anime), achieve a better picture quality than most anime and cartoons DVDs in the market.

But I would like some help to figure out which XviD settings, matrix, etc I need in order to obtain a picture "blocks and artifacts free", without ugly dark and high movement areas. Something that you look at and barely can see that the video is compressed, looking very close to a analog signal. Unlike movies and live action stuff, picture details is not a concern, the main concern is to get rid of artifacts. Bitrate could be around 3000 or more (but avoiding overkill).

So, any suggestion ?

Thanks in advance...

[Prettz]

You might try the hvs matrices (hvs-good, hvs-better, hvs-best). They're very good at giving a crisp picture while not producing anywhere near as many ringing artifacts as the standard, PSNR-tuned matrices (H263, MPEG).

[Soulhunter]

What, anime @ high bitrates ???

Please give Y.A.C.Q.M. (its in my sign) a shot... :)

But dont forget to post some feedback about the result !!!


Bye

[vigi_lante]

I hate to say this, but it looks like that MPEG2 is much better than MPEG4 for high bitrates video (mainly with noise or interlaced source).

The difference using XviD with all these matrices with high bitrates is barely visible, in comparison with, let's say, a XviD using about 1500.

Sad, but true. I guess that I will have to learn to like MPEG2. :(

[Sergei_Esenin]

If your MPEG-2 encodes look better than your high-bitrate MPEG-4 encodes of the same source material, you must not have XviD--or your decoder--configured optimally. There's a lot more to configuring XviD than just the matrix.

What are your XviD settings--and which decoder and settings are you viewing with? And which MPEG-2 encoder and bitrate are you comparing the results with?

[Blue_MiSfit]

Since it's a analog signal, the picture is not compressed, and despite the lower resolution and noise, the video quality can be considered better than DVD (mainly because, as I said before, the video is not compressed).


I think your idea is flawed. An analog TV signal is not uncompressed. It comes from a digital, compressed (probably via MPEG-2) source at some point, ultimatley probably the satllite streams your cable company gets its channels from. There is AFAIK no "all analog" TV anymore. There is digital processing somewhere in the chain, and you can be sure that it's not uncompressed when that happens, because uncompressed video is simply too big to work with.

IMHO, there really is no cleaner source than a good DVD, or perhaps a really well done (possibly high-def) DVB stream.

Regardless, It's cool that you're messing with cartoon content, it's a lot of fun to work with. I suggest no quarterpixel, adaptive quant lots of b-frames(3 max), h263 or hvs_good matricies(have not tried Soulhunter's Y.A.C.Q.M), chroma motion, VHQ2-4, Cartoon mode, trellis, and quants capped at 2-31

~misfit

[ObiKenobi]

Originally posted by vigi_lante
I'm basically talking about animated stuff (anime, cartoon etc) captured from analog cable TV. Since it's a analog signal, the picture is not compressed, and despite the lower resolution and noise, the video quality can be considered better than DVD (mainly because, as I said before, the video is not compressed).

So, I think it's possible, with the right filters to remove all the noise (easier since it's anime), achieve a better picture quality than most anime and cartoons DVDs in the market.

Nope, I'm sorry to say that this is not correct at all. First of all, your analog TV captures will be almost half the resolution of a DVD, somewhere around 330x480, having a very soft look with a very noticeable level of detail lacking. Secondly, these captures will contain artifacts such as cross coloration, dot crawl and like most TV broadcasts will have a strong analog enhancement applied that a properly mastered DVD will not have (even those DVD done using a Laserdisc master as a source will still yield better results). And like Blue_Misfit said the TV masters used to broadcast this anime/cartoon content have almost always gone through some sort of digitization and many times will have macroblocking in the signal (sometimes not very noticeable and sometimes quite noticeable). Now if you were to say that you could achieve better results using XviD if you had access to the digibetas used to encode said DVDs then I might agree with you.

[Sharktooth]

If you're going to use mid-high/high bitrates try also EQM AutoGK Sharpmatrix (aka EQM V2).

[vigi_lante]

Well, I was wrong about MPEG2 vs MPEG4. With a clean source and high bitrate, they are similar. But with a noise source, MPEG2 can do a better job. Unless, you encode the noise source with XviD using quantitizer 2.

And that's what I guess that I will do. I found that the only way to eliminate blocks, is to retain a good amount of noise, and to tell the true, for me a "dirty look" is much better than a "blocky look". Now I understand why you can find noise on retails DVD.

So, I think that I will just capture my noise TV analog signal, and keep the way it is. And it could be a good thing to keep the picture unfiltered, so I can in the future (with better codecs, filters etc)do a better job to restore it. :)

The only thing that I really would like to eliminate is the dot crawl, but it's not a big deal...

About TV signal...

I never saw on the analog TV cable picture, artifacts that could at least remind me that the picture is compressed the way it is on Digital Sattelite TV for example. I know that maybe, at some point, the picture is digitally compressed, maybe using MPEG2. But we are talking here about very high bitrates, with Studio Quality, almost or completely lossless. So, it will have a much higher quality (aka less compressed) than DVD. But there are some Sattelite TV services that compress the picture with a much lower bitrate, using MPEG2, in order to broadcast. This is not my case.

[ObiKenobi]

Originally posted by vigi_lante
I never saw on the analog TV cable picture, artifacts that could at least remind me that the picture is compressed the way it is on Digital Sattelite TV for example.

With the lower resolution of analog TV for many times you won't notice it, but it is there.

Originally posted by vigi_lante
I know that maybe, at some point, the picture is digitally compressed, maybe using MPEG2. But we are talking here about very high bitrates, with Studio Quality, almost or completely lossless. So, it will have a much higher quality (aka less compressed) than DVD. But there are some Sattelite TV services that compress the picture with a much lower bitrate, using MPEG2, in order to broadcast. This is not my case.

Except DVDs are authored from a lossless, higher resolution digibeta masters so you will still yield inferior results, not to mention the composite artifacts that are introduced into the signal that a properly mastered DVD won't have. So like I said in my previous post, I seriously doubt you will get a better quality encodes from capturing off TV then a DVD that is encoding from a far better quality, and higher resolution source.

[Mug Funky]

Now I understand why you can find noise on retails DVD.

actually, this is because commercial DVD encoding is mainly done through hardware with SDI interfaces, and hardware denoisers are either crap or expensive or both. and with the (usually) high bitrates on DVD, there's just no point wasting time and money removing noise.

the DVDs i've seen that have been denoised, i wish they hadn't been because they often look worse than a noisy source would.

weather or not you like the idea of digital compression, there's no way to avoid it, and besides that, its going to look better than analog at the same bandwidth (if the TV people aren't complete n00bs, which unfortunately they tend to be), just like a --preset standard mp3 off a CD will sound better than a microcassette of the same source (and probably a vinyl, depending on how expensive the equipment is and how clean the record is).

you may notice blocks with xvid even at quant 2 with smooth enough sources. this is a DC precision thing, i believe (could be wrong there), but if you do a 2-pass encode and allow quant 1, you should get better quality for the same bitrate.

[edit]

also remember that seeing as the broadcast people are certain to be completely stupid, you're going to see stuff in analog broadcast that'll make your eyes bleed. for example, sports broadcasts might come live with an all-analog chain, but delayed telecasts will probably be 3-4mbps mpeg-2, and they'll be re-compressed to the broadcast bitrate, then converted back to analog and sent down the cable. possibly there'll be another analog (maybe even composite) stage between the 2 recompressions. also, there might be a blended-field framerate conversion in there if the footage comes from another country.

for anime you're pretty safe from most of that, but my point is that analog broadcast will almost never be better than the DVD (i'd go so far as to say never 100% of the time, but i don't get ideal reception here so i can't say for sure - certainly the DVD would have to REALLY suck for it to be worse than analog broadcast).

[708145]

mug funky:

Did you try spp deblocking in those cases as well?
A quant2 encode with minimal spp deblocking helps with DC precision (no visible banding anymore) as well as decreases ringing.

bis besser,
Tobias