homevideo on cd. what format to use?

[kheperi]

Hi,

A collegue of me has a videocam (not digital) and lots of tapes with footage. kids and holidays and stuff. He likes to preserve the material in a nice and convenient way. First thing i thought of, of course, was using divx. but the images are interlaced (pal) so it might turn out to be rather ugly. Some interlaced material is very dificult to deïnderlace. Maybe a better option would be using mpeg2. Is that possible and is that a good idea? It would mean that i have to inverstigate a new terrein. Is there a good guide about porcessing homevideostuff?

[DJ Bobo]

There is nothing special about it being home stuff or not, capture it as usual in AVI with a Codec like Huffyuv or MJPEG then load it in TMPG and encode it to MPEG2.

BTW, if you capture in a resolution of 384x288, you won't even have to deinterlace, it will be smooth and clean and then you can encode it to DivX without problems, and I think 384x288 is high enough for home video.

[avih]

keeping it interlaced or not is a decision you'll have to make AFTER you test both options and (your friend) decides which one looks better.

imo, if the video is important to him, then he should keep it interlaced, since the quality is MUCH better (50/60 fps looks so much better than 25/30 fps). in that case, you should choose a vertical resolution of 576/480 (pal/ntsc) for both capture and encoding.

also, if he decides that keeping it non interlaced is the way to go, then the clip should be DE-INTERLACDE first, and only then resized to the desired resolution, since otherwise, it would be deinterlaced using what's known as 'blend deinterlace', which is one of the 2 'cheap' methods for deinterlacing (the other would be select odd/even). a good deinterlac filter could be smart deinterlace or tom's MoComp deinterlace.

if he wants a 'convinient' storage format than either vcd or svcd are good options, since you can use a dvd player to watch it. (so it's mpeg1/mpeg2)

bottom line: considering the info u gave, you have 3 main options imho. keep it interlaced as svcd (mpeg2) or deinterlaced as svcd, or deinterlaced as vcd.

and btw, the vcd option, eventhough seems a bit 'outdated' can give quite pleasing results, especially if the person using them is not a video 'freak'. it also let u store about 70-80 mins per cd, while the other options would probably give less.

cheers
avi

[theReal]

one more option would be 50fps Divx with either full or half resolution.

But that is probably not a good idea for "normal people" (=not video freaks) because the files get big (well, acceptable in half resolution) and they will only play on really fast computers...

[kheperi]

yes i thought of that too but thats really not a nice way of doing things. I guess that mpeg2 would be the best way but thats new to me so i'll have to experiment with that. But i think i first could look how divx turns out.

One of the weak aspects of divx to me is that it doesnt support interlaced video. Ok interlacing is terrible, maybe never should have been invented, but 25 frames per second doesnt look too good in scenes with pannings and so. Looks rather bad actually. hmmmm maybe i should try a go at the 50 fps technique after all...

Thanks for the replys guys!

[DJ Bobo]

50fps DivX is crap, don't ever use it if you can avoid it! there is line jitter like hell!

[theReal]

there is line jitter like hell!

With Gunnar Thalin's Deinterlace Smooth? No!

I experienced line jitter with tv captures, but I was always able to remove the very heavy jitter by either using or not using (depending on the capture) "complementparity()" before "seperatefields()"

Then, if you just use field bob to combine the fields, the top and bottom of the picture flicker (because the first and last line are displayed every other frame only). With Deinterlace Smooth this is all gone (but the filter is so damn slow!)

[octapus]

Dj Bobo:
Why is it that if you capture it at resolution 384x288, video will be smooth and clean? Please if someone can answer this as THEORITICAL as possible since i use these kind of resolutions(two times smaller than PAL maximum) in my tv capture and it's true that output comes very good almost without any other need of deinterlace procedure.

[theReal]

any resolution equal to or smaller than half height (=288 lines for PAL) is not interlaced at all because one field has 288 lines. Anything above that must use the second field as well and is therefore interlaced.

[DJ Bobo]

@ theReal
Can you please look for me here: http://forum.doom9.org/showthread.php?s=&threadid=27296&perpage=20&pagenumber=3
I use that bob/decimate method to get an acceptable output out of the damned Trigun DVDs.
The only inconvenient of this method is line jitter, which is quite annoying at times.

Do you know how I can get rid of it?

[theReal]

I'm not sure about the decimate - isn't that for ivtc-ing?

I have only made some 50fps clips from PAL TV-captures and I tried the different suggestions from www.100fps.com

Scroll down the page to the "what to do next..." section, there are three methods for creating a 50fps clip of which 4b, weave & progressive scan with Gunnar Thalin's Filter, gave the best results.
I tried the bob() method in avisynth a minute ago with a DV file and the result was excellent. Maybe it compresses a little less than with the Deinterlace Smooth filter, but it was much faster and it also looked good. No jitter...

Below this, he describes solutions if you still have some problems with jitter and jumping movement:

a) Be sure that you don't have a film with uneven number of lines (e.g. after cropping)
b) Experiment by adding one or more of the following commands:

ComplementParity
AssumeFrameBased
AssumeFieldBased
SwapFields


So you could try:

AVISource("Yourmovie.avi")
complementparity
separatefields

c) Change the field order in the VirtualDub filter you are using: So check "Quarterfield up/down" instead of "down/up", or check "Swap fields" or "Even fields first", depending upon which filter you are using.
for me, complementparity() was sometimes necessary, sometimes not, depending on the captured file.