DVDX using Divx Pass 1 vs, 2

[bassmadrigal]

I use DVDX and the Divx 5.1.1 codec. I have done many searches on this and other forums and cannot find an in-depth answer. I have been told that using two pass is better than one pass, but it takes so much more time. Is it really necessary? Or bennifical? I would like to rip movies as fast as possible (because I am working on getting my collection in the computer and if it takes 4-5 hours it will take me months to do my collection.) Any other pointers on what settings to change that keep quality high but encoding time low would be greatly appreciated. Oh and if someone could give me an in-depth answer to what the different passes are would be great.

By the way I encode all my movies to 700MB so I can keep them on CD also. (No DVD-Burner yet)

Thanks in advance.

[killingspree]

hi and welcome to the forum,
well to make it short, if you are going for one cd only a 2 pass encode is absolutely necessary. quality will decrease significantly if you do not use it. it only makes sense to encode movies with one pass if you use a fixed quant (e.g 2) - which will return much bigger filesizes than one cd though!

even using 2 pass encode i honestly wouldn't recommend fitting all movies on one cd. there's a couple of movies that will simply turn out horribly if you want to fit them on one cd!

to the details on the passes: in first pass, divx creates a dummy avi file encoded at quant 2 (more or less highest quality possible) and gathers information about the movie. which scenes compress well, which do not, etc. then in the second pass it uses the information of the first pass to distribute the available bitrate as good as possible.
Now if you do only one pass, the encoder still uses variable bitrate, but since it doesn't know what comes up in a couple of minutes it has to allways check that the average bitrate is achieved within a rather short section of the movie. therefore, scenes that only require a low bitrate will get more than they'd actually need, and exactly this bitrate might just be missing in low compressability scenes elsewhere in the movie!

hth
steVe

[bassmadrigal]

Thank you very much for the info. I do understand that some movies should be seperated. What is the lowest bitrate you would want before splitting into two cd's. Also what is the quant? And is there much I can do to help speed up the encoding? Right now I am encoding at about 25 fps. I know I shouldn't be complaining but if I can speed it up more it would be awesome.

Thanks again.

[killingspree]

1) well you can't define a specific bitrate under which you should split a rip to 2 cds, as it very much depends on the compressability of a movie. as a rule of thumb though, i wouldn't put a movie of more than 90 minutes length on one cd. generally i would recommend to use gordianknot or autoGK for your task. those will check the compressability for you and help you in the decision as to when you should go for 1 cd or rather pick 2 cds.

2) quant is a method of using a fixed quality setting for a movie. in this method you cannot predict the filesizes upfront, but you'll have a guaranteed quality. for a detailed description, pls search the forum!

3)speeding up your encoding time with dvdx is only possible by tweaking the encoding parameters of the codec, gordianknot or autogk will allow much more configuratibility! i recommend you take a look at those programs!

hth
steVe

[dragongodz]

speeding up your encoding time with dvdx is only possible by tweaking the encoding parameters of the codec
wrong. you also have different options. such as in input settings you can change the idct routine to mmx or sse or sse2 and in output settings the resize also has mmx,sse and sse2 versions aswell as bilinear, bicubic or TAP versions. these all have an effect on speed. DVDx 2.3 even supports dual cpu and HT in the decoding to increase speeds for those with such cpu setups.

gordianknot or autogk will allow much more configuratibility!
DVDx was designed for ease of use, especially for beginers. more options does not always a better program make in such cases. people should remember that before dismissing DVDx offhand and constantly reccomending other programs. :)

[killingspree]

Originally posted by dragongodz
wrong. you also have different options. such as in input settings you can change the idct routine to mmx or sse or sse2 and in output settings the resize also has mmx,sse and sse2 versions aswell as bilinear, bicubic or TAP versions. these all have an effect on speed. DVDx 2.3 even supports dual cpu and HT in the decoding to increase speeds for those with such cpu setups.
sorry, i stand corrected...


more options does not always a better program make in such cases. people should remember that before dismissing DVDx offhand and constantly reccomending other programs. :)
that's not what i said. as you quoted quite rightly i stated that autogk and especially gordianknot allow a greater amount of user interaction and therefore, i recommended it, as bassmadrigal was looking for a way to speed up/optimize the process. i probably should have pointed out more clearly that the usage of gordianknot also requires a way bigger amount of time you have to invest in order to get the knownledge to create the results you desire. if he had asked for a method that requires him to know very little about the process and doesn't need a lot of user interaction it would have been completely different and in this case, dismissing DVDx would have probably been wrong.
still point is, I personally like the GK suit better, and therefore i recommend it. recommendations tend to be based on personal opinion and should be taken as such!

kr
steVe

[bassmadrigal]

Would you recommend me to move to another program. I have been plenty happy with DVDx but if another program does just as good but is faster (and not too hard to learn.) I don't think of myself as a ID10T but I am really new to encoding and ripping (just barely got the hard drive space to do it, 4.3 GB on a 400 MHz processor and you can see why I didn't do this in the past). Any way I am open to any suggestions, but if you suggest other programs and I sue them be forewarned that I will probably be making more posts to this forum:D

Thanks again for the info.

[killingspree]

if you are satisfied with dvdx, go on, keep using it! if you do want to try another solution to test, which works better for you, go ahead and try autoGK. It is easy to use and there are awesome guides that help you learn how to work this program!

if you decide to give autoGK a shot, we'll of course be more than happy to help you out with any questions/problems you might have!

kr
steVe

[bassmadrigal]

Okay I tried autoGK last night and it was SCREAMING fast. I did a 1:49:58 movie in 2:10:47. The same movie on DVDx took 3:14:32. But the quality on autoGK left ALOT to be desired. It was plenty easy to use (easier than DVDx except having to rip the DVD to the hard drive in a seperate program. Took me awhile to figure that one out.:D ) The quality on the autoGK rip was horrible compared to the DVDx rip. (And yes I did do it to 700 MB) The resolution was lower and the bitrate seemed lower.

But my question now is: does the full GK (I am not even going to try and spell it) offer more options (ie the ability to specify your own resolution AND bitrate) and is it just as fast?

Like I said I am willing to try others but I don't want to sacrifice quality for speed.

[dragongodz]

just a quick note on DVDx settings again.

in input settings. check your idct that is selected. since you have an amd 2600+ select the SSE option. audio downsampling, since you are going to avi you dont have to downsample to 44khz so select 48khz(no conversion), assuming your source is from dvd.

in output settings. select YUY2 in the "Export" setting and then reselect and setup the Xvid codec. for the "Resize" setting again you can select 1 of the SSE options.

those should all make your encoding faster.

[manono]

The resolution was lower and the bitrate seemed lower.

It encoded faster because the resolution AutoGK chose was lower. The resolution it chose was lower because AutoGK encodes within certain quality parameters and was forced to choose the lower resolution to keep within those parameters. That said however, if it is forced to drop the resolution too low, then of course the result will look like crap. But you can choose your own horizontal resolution in Advanced Settings. If the movie is the same, the file size is the same, the audio bitrate is the same, then the video bitrate is the same also. You can open the movies in GSpot and find out the bitrates.

Yes, of course the full Gordian Knot offers more options. but judging from what I see so far from you, I'd say you're not quite ready for GKnot.

Your original post said you were ripping your collection to the hard drive. So, if file size isn't much of a consideration, then you might try the fast 1-pass Quality Mode at default settings. The file size will be larger, but you said that quality was your main concern. You should be very pleased with the resulting quality, if not with the file size. Some movies weren't meant to be put on 1 CD.