Thursday, March 29, 2007

So I swore off of re-encoding MPEG files...

...until I remembered that a lot of my source materials are either in PAL, or are taken from shoddy VHS (and in some cases, shoddy LD) and at bare minimum need either a framerate change or a quick color correction to be up to standard.


So, back to the MPEG mines. But I've found a lot of variables in my encoders which can change the outcome drastically... particularly, that of resizing.

See, PAL DVD's - as I've gone over before, I'm sure - are 720x576, while NTSC DVD's are 720x480. Despite the upgrade in resolution, they usually don't look any better though: the bitrate limit is the same for both resolutions, and if anything, encoding more bigger frames per second at PAL resolution will net you more fugly MPEG artifacts. Fun, huh? TMPGEnc and CCE both have built in scalers, to change the source resolution to whatever the hell you want in to be, in this case, 576 to 480. So I decided to remove that variable, which in TMPGEnc changes the resolution of the video file for no apparent reason, squishing it and making everything a bit too thin. So, using Video God - aka VirtualDub and it's myriad of plug-in filter magic - I used the generally loved Lanzcos3 filter to feed a pre-resized 720x480 file into my encoders.

Both TMPGEnc and CCE were set to the same specifications - 6mbps average bitrate, 2mbps minimum, 8mbps maximum. I could use CCE's peak bitrate of 9.8mbps, but since I have a total of 3 surround sound tracks, bandwidth would take a load in its' pants and be nowhere near DVD spec, thus the peak was dropped.

This is the original OVA Films DVD (resized to NTSC resolution in photoshop to not throw me off too hard), and... well, as you can see it's no looker to begin with. 80's anime, with flashing lights, speed lines and strange optical effects, is just asking to look like shit on low bitrate MPEG-2. There's a LOT of nasty MPEG related noise in the background, though D and Doris look OK for the most part. There's a liiiiiiiiittle bit of noise on her choker and right shoulder, but that's about all that's worth bringing up.

This is the CCE SP shot. The background looks okay at first, but check out Doris' shoulder and shoulder pad. Compare D's face for a minute or two. And, amazingly, check the fact that while the background is now softer and less defined, there's MORE grain over everything else! How the hell can that be?! All that grain wasn't there a second ago... unfortunately, CCE's downside is its' tendency to add noise ("digital grain") to everything. Even more frustrating is that the new grain on Doris' shoulder is random and rainbow colored (from the previous shot of Chula spitting spiders everywhere), making this shot look like it has composite artifacts, even though it's taken from a component, and possibly High Definition master. I guess compared to a $99 DVD recorder, or even some crappy freebie encoder that comes in Nero or whatever, this would be awesome quality... but hardly the pro-level stuff that makes everything in the consumer video editing (and professional!) world thinks is worth $2,000.

And then there was TMPGEnc Plus. On the one hand, Doris' shouldepad is still nice and noise free. Also, the background doesn't become mysteriously... soft, like it did in CCE. In some ways, TMPGEnc is a very good encoder that stays true to the source. Unfortunately, the same problems I found last time persist: D's face has a big nasty macroblock under his eye, Doris' skirt has come to life with squiggling Lovecraftian artifacts, and most frustratingly, the black outlines in Doris' clothes are STILL sharper, despite the accompanying artifacts.

Despite the horrible blocking, the TMPGEnc version - through a competent resize filter - winds up looking more like the original source video. This flaw sucks, to be sure, but really: do I want a grainy and rainbowing video, or a smooth and blocky video? It's like asking someone if they want AIDS or cancer: neither answer is "correct", but I think the second option is the latter of two evils, if only by a slight margin. That CCE still adds noise when softening the hell out of the transfer is all kinds of unacceptable, and if I wanted to soften the video in TMPGEnc I could do that without a layer of artificial dithering grain on top.

Procoder tests may happen if I can find a working copy to steal. Er, crack. Warez? Download! There we go. Yes, download.

Looks like my quest to find a perfect encoder has failed a little bit. As DVDShrink beats both TMPGEnc and CCE hands down, I'll use that for projects that don't need extensive remastering. While I regret that a layer of warm and crispy artifacts of one kind or another simply come with the territory of MPEG encoding, I'll continue playing with the encoder that sucks marginally less - in this case, TMPGEnc - and see if a tolerable result is instances like this is even possible.

We'll find a way.

Oh yeah, turns out I'm in the hole for $1,600+ on top of whatever debts I had before my apartment exploded. I try not to bitch about my personal life here, but I bring it up because if I ever had an incentive to open (Say what? I don't own that domain... or do I?), this would sure as hell be it. Stay tuned for more info. Hopefully.

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