VirtualDub question: resizing...

[bigsexvideos]

I tried to resize large Divx AVI's (4-8 MB) to chop them into 300 kb pieces for movie galleries.
But (probably because I'm on Windows NT) I can't get the filesize to be significantly lower.

How do you guys do that?

[arthurdent]

To steps:

1. Save segmented AVI
2. Limit number of video frames per segment to XXX

HTH

:cool:

[bigsexvideos]

Thanks for the reply I'll check it out as soon as I can. Probably this afternoon.

[Mole]

Under the "Video" tab, make sure you've selected "Direct Stream Copy" and NOT "Full Processing Mode"

Also, you MUST start your clip with a key frame. So use the button with a key icon to navigate and find the key frame. You don't need to end the clip at a key frame, but it must start from a key frame.

You should check out this URL for more guides. Their web board is also frequent by almost all the important people in the DivX community, including the author of VirtualDub.

Doom9's MPEG Palace (http://go.to/doom9/)

[baddog]

bigsexvideos,

well, I hate to disagree with most of the advice given here, however, do use full processing more (video & audio), no sound, video compression settings should be Divx Mpeg 4 low motion or fast, smoothness 100%, data rate sampling 296, should be able to get 10 sec clips at 400k or so.

[Mole]

The movies are already compressed with DivX. The quality will be very shitty if you re-compress that again with DivX.

If, the resolution of the video is relatively high, such as 640x480 or something, then you can resize down to 320x240 and delete out the sound and basicly do what bad_dog told. Except, I'd set bitrate at 250, keyframes every 4 seconds and smoothness at 0%.

At such low bitrates, any scenes with heavy motion or details will cause the frame rate to drop. If ou set the smoothness to 0%, it'll retain the frame rate and the video will be more blur at fast scenes. But on slow scenes, it'll be about the same crispness as if you set it to 100%.

Anybody who doubt this should try to encode and see yourself.

I have a sample clip which will demostrate this problem. It's an MPEG and you can try to re-compress it to DivX and see yourself.

[baddog]

Mole,

I have 4 MGPs, and I have to think that using the numbers you are talking about, the likelihood of you getting a gallery accepted on one of my sites is pretty slim.

I also run MogulTeam, which is a group of webmasters that deal with nothing but video content, which includes teaching those that are new to the broadband side of the industry. This is not to say I know it all by a long shot, but I do try to stay on top of things, which brings up a couple questions.

First, what version of vdub are you using? I recommend 1.3c and the numbers I talk about are relative to vdub1.3c with divx311_alpha

also, I thought the keyframes dealt more with the use of the keys on the control bar, key frames 4 sec and when you hit the key it gave you a 4 sec clip, set it at 10 sec and it gave you a 10 sec clip.

Also, how do you resize a video down to 320x240? Better yet, why?

I think I see a problem, people are marketing videos with a static pic mentality. For instance, if you are putting 10 bullshit clips on a gallery, consider using 4 or 6 nice ones instead.

Also, do not waste bandwidth submitting movie galleries to TGPs. I am sure the TGP webmasters love to see you submit there and will post them all, but you are missing your target market.

If you are using movie galleries, I hope you are pushing video sponsors, like MyMoviePass, the only all-movie AVS (shameless plug, sorry). Your target market should be those with broadband access, and people with broadband access are not going to TGPs, they are going to MGPs. They have no interest in working their way through countless links to sites with static pics trying to find the link to a site with movie content.

I have heard the argument that people with dial up have credit cards too, but in all honesty, you do not want their money, at least not on your movie site. They try to download a clip and end up taking forever. Get a few thousand of their closest friends doing the same thing, all of a sudden, no one can get anything off your server, because it is so bogged down. Now this may be a great way to cut down on bandwidth usage, but it makes for a very difficult conversion. I compare submitting movie galleries to TGPs the same as selling microwave ovens to the tribesmen of the Amazon rain forest. Can end up causing nothing but a lot of returns (chargebacks) because they can not get your product to work for them.

If having a problem trying to find MGPs to submit your movie galleries to, go check out our submit tool for MGPs, http://moviecommander.com (another shameless plug, I know) it is free and easy to use and install, and submits to MGPs without violating anyones rules. You can also go there to add your MGP to the submit list.

Hope this helps a little.

[Mole]

I wouldn't recommend using DivX for TGP galleries anyway since many people don't have the codec installed.

However, I do use DivX for the movies I have on my pay and AVS sites since IMO, DivX currently gives the best quality vs size. Of course I also provide links for people to download DivX codecs for all platforms.

No offence, but I can see from your reply that you haven't grasped even the basics about video encoding.

The current version of VirtualDub is 1.4.7. v1.3c is very ancient. It's full of bugs and lacks a lot of functions which were added in later release. I wouldn't recommend v1.3c to anybody.

You are totally misunderstanding what keyframes really is.

Also, smaller resolution videos will benefit because they'll require lower bitrates to get a decent quality. The size will then be smaller.

When compressing videos, it's all about bitrate. It doesn't matter whenever the clip is 320x240 or 640x480. If you compress with a bitrate of say 500, both clips will be about the same size.

If you really want to learn about DivX and general knowledge about video encoding, you should head for the Doom9's link in my earlier post. He has a lot of useful guides and you'll learn a lot. You should also hang out in the forums over there.

Most of the terms when it comes to DivX is also relevant for other formats such as MPG or Real.

As a last note, I bet that I'll be able to compress any MPG clip to DivX at least half the size at roughly the same quality.

[baddog]

well Mole, I guess we will have to agree to disagree.

I am quite aware what the curent version of vdub is, but I also know that newer is not always better. We usually cut .wmv clips so 1.3c works where as the later versions do not. You can believe it or not, makes no difference.

BTW, when I use vdub1.3c combined with divx311_alpha my galleries will get accepted on Richards-Realm, every time. If there was a need to provide a codec, they would not accept them, ever. They have some of the most stringent standards around, so you go ahead and use the latest version of vdub if you want, I will use what works.

I am also quite familiar with bitrates and their effects on file size. What exactly is your contention on what a 4 sec key frame is going to do? I would be quite interested in hearing this.

For the record, you are the one that brought up reducing a video from 640x480 to 320x240, not me. I am not sure, but I am guessing that 320x240 may be a standard of some sort as I have never resized mine but all seem to be that size. I completely agree that it is all about bitrate, although I think your 500 is a little steep.

If you want to get an idea of what vdub1.3c with the numbers I spoke of can produce, go to http://a1der-babe.com/histoy1.html and you can judge for yourself. In fact, everyone can.

[Mole]

*If* you are a seasoned movie poster, you will know that a lot of larger movie only TGPs either do not accept or advice AGAINST using DivX.

As far as I know, Richards-Realm does not specialize in movie galleries. Naturally, he *might* not know about DivX as much as a site which deals in movie galleries. He might also be a bit more relaxed about DivX than most other movie TGPs.

The fact is still that people will need to have the DivX codecs installed in order to play them. DivX is .AVI files and NOT .WMV.

It doesn't matter what version of VirtualDub or program you used to compress the clip for that matter. If the compression is DivX, it will require a codec. VirtualDub is just a tool for cutting and editing. You're not just limted to saving as DivX .AVIs but any other format provided you have the codecs installed.

Listen, I have no plans to explain very basic stuff such as size and key frames here.

If you just took your time to head over to the site I mentioned and read their newbie FAQ, it will all be explained to you what key frames will do and why the particular size I mentioned. Because of the nature of MPEG, video resolution must be dividable by either 16 or 32.

I suggest you head over to Doom9's site and read their FAQs and guides. If you still have questions, go into the forums there and post your questions. There's lots of very knowledgable people who lurks around there. But if you're gonna walz in and start with questions covered in the FAQ or guides, be prepared to get a link slapped in your face.

The 500 bitrate was just a number I used to state my example, that's all. I did not say that people should use it.

[baddog]

Mole,
You are telling me that as a seasoned movie poster, you are submitting movie galleries to TGPs? Well that makes a lot of sense, not.

For the record, Richards-Realm has a static pic section for TGP users and a section for those posting galleries to movie post sites (MGPs). You might want to try using the method I said with Media Player 6.4 instead of 7.0. Windows made it so avi would not work with 7.0 without a codec, 6.4 does not appear to have the same problem.

thanks for your most valuable input, I may take a look at the site you suggest, if so will let you know what I think, . . . if it is positive.

I try to keep negative comments to myself whenever possible.

[baddog]

by the way, I said I cut wmv clips, not that I cut avi clips, I am aware that vdub will give you the end result in avi format.

a little tip, if you then encode the resultant avi with windows batch encoder, not only will you end up with a smaller file, but no codec is required at all

[Mole]

In this case, we're talking about two different things. If you're cutting WMV files, you shouldn't have refered it as DivX at all.

I'm talking about DivX .AVI files while you are talking about M$ Windows Media files.

Although DivX is based on Windows Media 7, DivX provides a lot more flexibility when it comes to encoding, cutting and editing.

Windows Media Player 6.4 or newer comes with the WM7 codecs while WM8 codecs comes with Windows Media Player 7.

[baddog]

Mole,

Are you suggesting that I can not cut up say a one or two minute .wmv movie clip into 10 second .avi clips using vdub1.3c and divx311_alpha? Please do not tell me that or I will have to redo hours and hours of video clips and that would take days.