VCD to H.264/AVC. Best "formula"?

[PuzZLeR]

I'm trying to convert my VCD (MPEG-1) files to H.264/AVC.

Yeah, I know, I'm not getting much file size advantage, or quality advantage, and having less options with consumer electronics, etc.

However, I do want to encode for the future and want to stick to one format. As well, it's not a waste of time because I know I can get a smaller file size still and with deblock filters such as Nero Recode, maybe even improved "visual" quality given all those blocky artifacts from MPEG-1.

Two questions regarding VCD to H.264/AVC conversion:

Given the typical 1150kbps CBR of most VCD files, and the better efficiency of H.264/AVC, what bitrate should I encode in to best maintain most of the quality and get a smaller file size? Anybody with experience in this?

As well, I find MP2 audio in VCD doesn't translate well to AAC (too much distortion). Any tips on this? (Or should I maybe ask this in the audio section?)

Thanks in advance.

[jman98]

You CAN'T improve the quality over what you have to begin with. It's impossible. It's not good that you think you can. The best you can hope for when re-encoding is that the re-encode is not worse than what you started with. Given how video encoding works, you need to understand that converting from one lossy format (VCD) to another (H.264) is NEVER going to give you better video than your source. Most often it will be worse.

I doubt that anyone has done this because there is nothing to be gained by it. File size issues become less and less meaningful as time goes on. Given the likely backwards compatiblity with CDs that all future devices will probably have, you have nothing at all to gain by doing this and a lot to lose. Trust me, in 5 years (or maybe less), disk drives will be so big that you won't care at all about this issue. We already have 750 GB drives for PCs. In 5 years, you'll no doubt have multi-TB drives available.

MPEG audio on VCD isn't at a high enough bit rate. I'm not up on AAC conversions, but no doubt your results are caused by the source. Typical MPEG audio bit rates on VCD are roughly like 128 Kbps MP3 quality. I'm just guessing here, but maybe converting the MPEG audio source to WAV first might help as AAC might have better ways to convert WAV than they do MPEG audio. WAV is lossless, so there's no harm in trying to convert your audo to that.

[Cornucopia]

Nahhh, same goes for lossy audio compression as it does for video compression.

I would actually disagree with you on the evaluation/figures of MPEG audio for VCDs. It's locked in at 224kbps stereo. This is actually PRETTY GOOD quality for MP2 (equivalent to 192kbps MP3), one of the few things that shine with VCDs, particularly compared to the default video compression (1150kbps).
Any "distortion" is a result of someone badly digitizing in the 1st place. You'll never hear distortion on one of my (many) VCD releases...

Otherwise, I'm in agreement with jman98. VCD material (MPEG1 container, MPEG1 video/still, MP2 audio) won't lose compatibility FOR A LONG TIME TO COME. Just like CD audio. Newer players will continue to maintain compatibility, especially as it's trivial to include technologically and just makes more marketing sense.

Scott

[jman98]

Thanks for the correction about the audio, Scott. I read somewhere recently that someone claimed that 256 Kbps MP2 was equivalent to 192 Kbps MP3, so that's what my numbers were based on. I have to admit that personally I think 224 Kbps sounds pretty good, so I bow to your knowledge.

[edDV]

I think he was making a joke.

[PuzZLeR]

Thanks for the response to my post my friends.

For video:
We all know that the limited efficiency of MPEG-1. What you can get at 1150kbps in MPEG-1 is practically DVD quality with AVC.

But -I also fully understand that you can never gain quality by re-encoding, only if you're lucky enough to get something "as good" - something that the naked eye can't notice in difference. However my H.264/AVC encoder, Nero Recode, has this real cool deblocking feature that is very effective. No, it doesn't "improve" the quality, only makes it look better (in most cases) by restoring on that blockiness somewhat that is so common among many VCD files.

I guess it's not really a space issue with me. I have tons of space with my external HDDs (and can always backup on DVD-R). It's really an issue of tidyness. I would love to have all my video in one common format, especially if AVC SHOULD be a standard in the future, much like MPEG-2 is today.

I do agree that VCD will be supported for many more years, so maybe I should hang on to it. Would anybody be so kind as to give me their comments on SVCD with this topic? Now, compressing this format should give me space advantages.

For audio:
I confess that MP2 audio on most VCD files actually sounds great. It's got good clarity and even at high volumes. However, AAC seems to be the standard for H.264/AVC video files (if I decide to convert after all) and I don't want to disrupt the ecosystem. I will definitely now experiment with .wav and "muxing" and "demuxing". Thanks for the tip.

[edDV]

Thanks for the response to my post my friends.

For video:
We all know that the limited efficiency of MPEG-1. What you can get at 1150kbps in MPEG-1 is practically DVD quality with AVC.

But -I also fully understand that you can never gain quality by re-encoding, only if you're lucky enough to get something "as good"

You only get those advantages if you have access to the uncompressed source file. Once you encode to MPeg1 what you have is MPeg1. Further re-encoding degrades from there.

AVC isn't magic, you get a 2-3x compression advantage vs. MPeg2 but only from the same uncompressed source.

[PuzZLeR]

I'm starting to realize that maybe MPEG-1 is a very different beast from MPEG-2, especially when the original "uncompressed source" is not available.

I've compressed lots of MPEG-2 files down to tiny H.264 files with all the noticable quality intact very successfully. It was worth it.

I was hoping to convert my VCD files as well just to have one common format going with all my H.264 clips.

However, I'm starting to realize that MPEG-1 is rather "brittle" if compressed further due to its limitations.

I can see SVCD and even DivX files compressing to H.264 with some level of success, but MPEG-1 is a rather ancient and whithered technology and would melt with further conversion.

Anyway, I appreciate the replies folks. If anybody does have successful experiences going from VCD to H.264 I'm interested, but in the meantime, I'll hang on to my VCD files a little longer.

In the meantime I still have tons of MPEG-2 files left to convert and until encoding times and technology adapts to H.264, I can leave my VCD files last.

Maybe I'll ask this question again next year, which would be eons away in computer tech years.

[Soopafresh]

You can enhance the perceived quality of your Mpeg1 file somewhat, but it is going to take some work.

Here's what's not in your favor:

352x240 resolution

1150 Bitrate

Here's my favorite test video clip encoded to that resolution. Notice the macroblocking and flicker.

mpeg1.mpg

Here's the clip filtered with Avisynth and "upresed" from 352 to 480. Macroblocks almost gone, flicker somewhat reduced, but now you have to start watching for halos.

example_480.mp4

Blown up to 640, the artifacts become much more noticeable. I added grain to mask it a bit, but you can't do much to hide the garbage.

example_640.mp4

[Alex_ander]

There are some effective tools like NeatVideo (commercial VDub or AviSynth filter) to repair very bad videos. After deblocking and resizing new and sharp looking artifacts usually appear aroung image contours. They move with the image and look annoying at close distance. NeatVideo in most cases removes this by adaptive blurring (depending on spectrum analisys in group of frames) and works fine with just default settings. It is very slow (about 0.5fps) and only suitable for short clips. Surprisingly good results with rare youtube garbage, where FFT3D filter fails.