2-Pass (Variable Bitrate Mode)

[DMWRIGHT]

"If you want to encode a 2-hour show and be sure it fits on a 650Mb CD, then this is the choice for you"

Can someone explain 2-Pass operation? Do you need to bring video into capture device twice?


Thanks

[Enchanter]

In the first pass, the encoder analyses the video stream so that it can plot a bitrate curve for that specific video. It takes as long as it would when encoding the video normally.

The second pass encodes or compresses the video into the DivX format, all the while making use of the bitrate curve generated in the first pass. This basically allows the encoder to take some bits away from low-motion scenes, which do not require a lot of bits, and give them to fast-motion scenes, which will definitely require a lot of bits. Overall, this results in superior quality compared to 1-pass mode.

As for your capture, try to keep the AVI in as high a quality as possible (Uncompressed preferably though you will need gargantuan amount of HD space). You will need to capture only once. It is the encoding, as you've found out, that takes at least twice as long.

[DMWRIGHT]

Friend, you probably think I'm really dense. But, I'm having a hard time understanding all this. When I'm first capturing from my DV camera that's when I'm selecting the DivX codec for 2-pass. Or should I capture first by not using DivX format, then format AVI file using DivX.

[Enchanter]

Or should I capture first by not using DivX format, then format AVI file using DivX.

That's basically what I'm implying to you.

[DMWRIGHT]

I said I was stupid

Okay, I will import AVI, then open AVI in VitualDub to compress (2-pass) video and audio (make MP3). Then file will fit on VCD. Cool!!

WOW!! this is fun........

[DMWRIGHT]

I did it!! I put my AVI video (19GB) into VirtualDub and created a 1-pass and then 2-pass file. Hit PF4 and about 6 hours later had a AVI that's now 635 MB. Played great in DivX and Windows player. Now here's my problem, I took the AVI into Pinnacle Express to make a VCD thinging now if would fit on a CD-R disk. Express said video is 70 minutes to long. I then tried to make an MPEG file using PInnacle Studio, but, output MPEG file has no audio.

So, now I have a AVI video that is 635 MB but still can't make a VCD out of it. Does anyone have ideas how I can??

[Enchanter]

Have you tried sending in the file to either Nero 5.5 or TMPGEnc? Both are capable VCD makers too.

[DMWRIGHT]

I'm going to try TMPGEnc. I don't have Nero. I do have Easy CD Creator, but I think you need to convert to MPEG first. I'll let you know what happens.

[DMWRIGHT]

Well TMPGEnc did not reduce enough. I wonder if I went back and lowered audio brate. I set at 160 kbps. Or maybe take some video footage out.

[setarip]

How did you determine that "TMPGEnc did not reduce enough."?

Are you aware that VCDs are based on time and not filesize (similar to audio CDs)? If, in fact, your video is 70 minutes in length and VCD-compliant, you should be able to burn it to a 700Mg/80 minute CD-R (possibly even to a 650Mg/74 minute CD-R).

In order to be VCD compliant, use TMPGEnc to create an "MPEG1-VideoCD" (NOT simply "MPEG1) file (Do this by setting the mode under the "System" tab). Under the "Audio" tab, set to 44,100 (NOT 48,000) at 224Kbps.

Under the "Advanced" tab, set "Video Arrange" to "Center (custom size)" and set to 352x288 (or 352x240).

Under the "Video" tab, set "Size" to the same 352x288 (or 352x240).

[DMWRIGHT]

Your right, I said it was to big. But It is a "time" factor. I did choose TMPGEnc to create an "MPEG1-VideoCD". As soon as I have time I'll go back and make sure.

I'm using Easy CD Creator to burn VCD in MPEG format and Pinnacle Express to burn AVI. I don't know, maybe I should try another program to burn. Both of these programs are pretty "cut-and-dry".

One more thing, even though I have a time issue would you change audio brate to help make file smaller?

[setarip]

"would you change audio brate to help make file smaller?"

No, not if you want to keep the file VideoCD-compliant. If I remember correctly, the sum of the bitrates (video plus audio) MUST be 1,374 - with the presumed ideal video bitrate being 1,150.

Was your audio set to 48,000 or 44,100 for the TMPGEnc VideoCD setup?

[DMWRIGHT]

44,100, MP3 160

[DMWRIGHT]

Oh, one more thing I'm using version 2.5 (thirty day trial) of TMPGEnc. A wizard comes up. I don't see a settings menu option. Is there another version out there?

[setarip]

Click on the "Load" radio button.

Select "Unlock.mcf"

This will make all settings available to you (Press the "Settings" radio button)...