Re-Encoding for Archival

[larryc]

.... later on, when presumably he will know more on this subject.

Wow, condescending much?

[edDV]

I was implying the target customer of these cams fall into the "idiot" range (knowledge or excessive frugality). I'd expect people on this website to be more serious users.

Well, that's why I came here (serious users), but if this is the wrong forum for me, I guess I'm sorry.

I know my camera takes relatively "crappy" videos, but that's fine for me and it doesn't make me an "idiot". I have a tiny device that I can take anywhere with my and take ok pictures and ok video. I'd rather have an "ok" video from a camera that I carried with me than no video from a larger device that I didn't bring along at all.

Larry, thanks for finding the link on my camera specs, I should have looked it up first. Thanks also for jumping in and assisting.

I guess I kind of came to a place where everyone feels PQ is #1 and there are really very few other considerations. Personally, I'm not the type that can tell the difference (or really care, if I could) between audio at 320kbps and 128kbps and I'm sure the same goes for video. Shockingly, I'm not the only person who thinks like that. That's probably blasphemy around here though, but you guys should realize there are people who want that. Nothing wrong with educating them of the ramifications of not considering enough about PQ, but you could still help answering the question.

I have a 500GB drive for backup, I have a 1TB drive for my DVR and another 250GB drive for my other DVD. I really don't want to have external drives lying all around the house. Right now, I have these files on a laptop with a small HD and I really don't care if I take lose a small percentage of PQ if I can get a file 1/3 to 1/2 the original filesize as long as it's also in a format that should be around many years from now (which I'm thinking H.264 will be).

Sounds like encoding in Handbrake to H.264 with a CQ of 50% to 60% is probably the way to go here.

Maybe some of the "more important" videos I'll archive the originals and the "everyday" videos, I won't bother. That make you all happier?

Seriously, this was an interesting discussion either way.

My intention was to draw two alternatives for archive. Preservation vs. further compression. Preservation has been covered. Don't recompress.

If you want to compress further here are the issues. MJPEG has all frames present. MJPEG compression is intra (inside) frame only*. You have 15 compressed frames per second. Further compression will add interframe (motion) compression to 15 to 300 or more (selectable) frames into a GOP (Group Of Pictures). MPeg is based on GOP compression. There is one full frame per GOP with the remainder containing only change information. Change information is determined by motion detection on a pixel block basis. The quality of MPeg GOP compression relies on separating pixel blocks in motion from those that are near stationary. If the camera was on a tripod, the motion detection would be efficient and most quality would be preserved. If the video is shaky (hand held) or noisy then GOP motion compression will be unsuccessful. When every pixel block is in motion, or seems so from noise, the encoder defaults to further intra frame compression to meet the desired average bit rate.

Bottom line it is all about preserving quality. If the source video is clean from the start, further compression will be more effective. If the source video is hand held and noisy, the picture quality will degrade rapidly with further compression.

Experiment with MPeg4 (h.264 and xvid). Compress until you like the quality vs. file size compromise. Your optimization will differ from mine.

[edDV]

[QUOTE=lexluthor5;1994173]

Maybe some of the "more important" videos I'll archive the originals and the "everyday" videos, I won't bother. That make you all happier?

Seriously, this was an interesting discussion either way.

I do the same. My camcorder videos are preserved at full 25Mb/s.

Simple news/info captures are encoded VCD MPeg1 (1150 Kbps) just because it is the fastest encode. I don't care about quality vs. time and file size in that case and I don't want to wait for an h.264 (500 Kbps) encode.

If I intend to send info to others, I'd suffer the xvid or h.264 encode times.

[davexnet]

I think all of us, err on the side of caution when advising users about family videos. A few in the past have
stated they want to create a format for the computer, and once it's done, they're going to reuse the tapes.
But the experienced poster immediately puts himself in their shoes, and realizes that if later on, the poster
wants to make a DVD, his best format may be long gone and he'll end up with a far inferior product now.

There's quite a few products that will do the job if you want to, for example, half the file size. I mentioned
I tried it on some medium bitrate movie trailers and I couldn't tell the difference on my LCD monitor
when comparing the original to the new version. In general, it's very hard to recommend a particular
bitrate - you may end up with artifacts where a particular "difficult" scene required more bitrate than was
allocated. Much better to encode in one of the quality modes - do a few tests and see if you
like the results. There's no great mystery to it, nor any hard and fast rules.
Good luck -

[usually_quiet]

.... later on, when presumably he will know more on this subject.

Wow, condescending much?

So you don't think the OP will learn more about a subject that interests him over time, that experience will not teach him anything useful, and that better tools than Handbrake won't become available to him?

[VegasBud]

Frequently, the best advice requires going beyond the question which was asked, and makes use of the total accumulated knowledge the "help giver" has at their disposal.

Some of the "VideoHelp" being offered (in this thread) is, in my opinion, being dismissed too quickly. The advice already given might take on fresh perspective if two concepts are considered:

1) Archives exist to preserve something for the future.

2) Technology has a way of advancing more quickly than can be predicted.

For a real-world example of the importance of those two factors:

Just in the decade (or so) I've been making use of digital video, the vhs tapes I shot long ago have been transferred to VCD and DVD. Each time, the source material was the original vhs tapes, but the output was quite different. Advances in hardware and software were what made the difference.

If I had discarded the original vhs tapes after digitizing them to VCD specifications, the DVD versions I later made would have been the same as the VCD versions...just bigger and blockier. Fortunately, I archived the original vhs tapes...in the hope that the future would bring technological advances which would let me extract more from them. Not only did that occur, it took less than a decade to become reality. Will technology advance even further, letting me extract more from the original source tapes? Like everyone else, I can't see into the future, so I just don't know. I do, however, know that if such technology does come about, I'll be able to take advantage of it...because I still have the original source (vhs tapes) to work with.

Since video cameras stopped using tapes, the digital files they create have become the original source. If you archive anything but the original source, you're limiting your future options. That may not seem like a big deal now, but the further you go into the future, the bigger the consequence becomes.

In that context, I can't help but agree with the advice previously offered:

The words Re-Encoding and Archival don't go together in the same sentence.

...don't do anything...easier, faster. Just keep what you have.

The file that comes out of the camcorder is your "archive". The file is already highly compressed h.264. Anything you do to recode will lower quality.

The OP (not only) gains absolutely nothing in terms of permanence of the format by converting from a better quality H.264 to worse, but he is losing forever the opportunity to convert them more competently later on...

As always, what anyone chooses to do in their own space is their choice. Advice offered can be considered or rejected. There is, however, an inescapable constant in life..."Actions have consequences". It's rarely a bad idea to take all the consequences into account before an action is taken.