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View Full Version : MPEG2 encoder for archive and rework later


callstreet
20th September 2004, 04:35
I have search through this forum and the internet but I'm not sure if I will be doing the right thing.

Ideally, I want to store video in some lossless format so I can work on it later - edit, denoise, etc. But the DV format and the well known near lossless codecs like HUFFYUV, MJPEG provide too low compression. I can live with DVD level compression, and indeed someone suggested here MPEG2 as the format for archive. MPEG4 are said to be no good unless perhaps I know how to clean up all the artifacts from, for example, NTSC capture, before compression. That's one of the reasons I need some compression like MPEG2, which perhaps allow me to store all the video in some manageable size files and experiment to improve them later.

I need MPEG2 like encoders to be able to write AVI files, that is, installable as a codec in windows. Otherwise, if I open an mpg file in VirtualDubMod just to cut out some footage for use, it will cost me another compression that is unnecessary and undesirable. That is, the direct stream copy doesn't work for mpg files. If that works, I will have a lot less problem because my main concern is the NTSC video capture. The quality isn't too good and already in MPEG2. I cannot afford another lossy compression without first cleaning them up with filters like denoise, spatial and temporal smoothing. I can do some recommended filtering first but I'm sure more can be done later if I understand more about the filters and experimental with the settings.

My first question is whether the commonly found codecs in Windows, like Cinepak, Indeo, etc, would be good enough if I set the quality to 100 or close to it? I couldn't find much quality comparisons but I understand that some are old, some are for video conferencing on the web etc. I doubt if I can minimize the loss even if I set the quality to 100.

MPEG2 codec like CCE and TMPG are out of the question as they are not free. TMPG is reasonable in price but I doubt if it is an overkill for some not so good video captures. Also, I wonder if can get the same quality by allowing a larger file sizes with other lesser MPEG2 codecs. Twice the size or more is reasonable but not that much as the near lossless codecs.

FFVFW is the only one that I found, which contains at least two versions of MPEG2 codec. That I can use with VirtualDub. QuEnc doesn't write to AVI format so it will cost me another compression if I just want to cut out some footage and save it in AVI.

So a simple question is whether FFVFW will satisfy my needs? And what's the recommended settings to minimize loss? For example, I read through the analogue capture guide, but I'm still not sure whether I need to deinterlace or not. I tried some other filters and some gave big improvements. So I need some encoders to store the video without limiting my chance to improve the quality later. And since the video is already captured in MPEG2 formats already (Instant DVD), which I couldn't do anything about, I don't think I loss much if I use the right MPEG2 codec just once more.

The same goes for the DV from my camcorder. If I can compression them to some reasonable size without losing much, I can get rid of the mini DV tapes.

Amnon82
20th September 2004, 20:26
Many wants for a eierlegende Wollmilchsau!

There is still another codec outside wich you can use in vd.
It is called ympeg. Download YMPEG (http://www.ympeg.com/YMPEGSetupDemo.php?id=1). It was before Freeware. Now it is payware. I didn't tested the newest version cos of the last version as it was freeware all sucks...

It can now also save in AVI.

But You can also use VirtualdubMod for open MPEG1 and MPEG2 files.

Hope this helps.

dragongodz
21st September 2004, 02:52
MPEG4 are said to be no good
sorry but that is plain rubbish. try xvid with the same bitrate as mpeg2 and the xvid one should look better. if you are going to use a reasonably good/high bitrate then you can also do things like turn off B frames etc to try and increase quality.

callstreet
21st September 2004, 03:35
The analogue capture guide here recommended DIVX3 over Xvid & DIVX5 for noisy motions. But I guess that's at movie-on-CD bit rates.

Actually the 1st thing I did was setting DIVX5 at the maximum 4MB/s rate. I had second thought when someone suggest to archive using mpeg2. I'm glad to hear that high rate mpeg4 is a good option. It's convenient as I can use the same codec for final work. However, my aim is slightly different - that the 'quality' is not the most important as that's only the immediate file. My aim to work on the compressed files again later, for example, when someone suggest some fantastic filters to improve the video.

Any other settings to 'minimize' the compression of mpeg4?

dragongodz
21st September 2004, 04:40
well you may want to have a read of this to start with
http://www.doom9.org/codecs-103-1.htm

as for settings. well for xvid as i said turn off B frames(called B-VOPs). dont use adaptive quant or qpel or gmc, no doubt others will say otherwise but this is just my opinion. dont use target bitrate but target quantizer set to 1. that should provide you with very good quality, it will also make the file pretty big of course. :)

Peter Cheat
21st September 2004, 04:54
XviD is very good for captures. When I am running low on hardisk space from the number of captures I do, I change over from HUFFYUV to XviD. For best results, turn of B Frames, set the I frame interval to 1 (all I frames) and do a constant quantiser encode (quant 2 is good). the .H263 matrix is good enough, but you can use the MPEG matrix if you want. The MPEG matrix will need a bit more CPU power. Make sure adaptive quantisation, gmc, qpel and reduced resolution are disabled.

The resulting avi will be indistiguishable from the source to the human eye.

callstreet
22nd September 2004, 07:53
Thanks for all the suggestions. It looks like Xvid is the solution to many people's whole life - PAL/NTSC VHS tapes, DV tapes, and now cheap, miniature wireless fun video camera images captured in some form. To me there's no final versions. You may one day want to take some clip out and make a music video! Compression levels lower than HUFYUV/DV, close to MPEG2 will allow me to dump everything to harddisk, DVD, CD's without thinking. Being able to be played in MPEG4 standalone players will be interesting.

Now just when I found some directions, my capture box broke, my early DV camcorder without A/D conveter nor passthrough broke. While I had the capture box for years I still haven't done anything much to my VHS collection. All the broken hardware maybe a blessing but I will have a lot to read to find some good hardware.

This is irrelevant to this forum but my next question, when I found the right forum, will be what's a sensible $500 range camcorder with a good A/D converter? That goes well with miniature wireless cameras.

TEB
22nd September 2004, 20:09
Hi. Interesting comments regarding archiving.
Does Xvid support 4:2:2 ? Im considering using CQ mpeg2 via Procoder 2. But if xvid could solve this purpose that would be cewl. What would be the recomended settings for eg. mpeg2 imx 50mbit iframe only in the xvid world? Quant 1? What would be the prefered container type for 2-3 hour movies in the absolute best quality Xvid could provide? Ogm? would avi be a good container for format for files in the 10-20gb size?

best regards teb