Realtime DV to MPEG2 encoder?

[bhwong]

Most DVD authoring software such as Sonic MyDVD and Roxio DVD Builder can capture DV clips and convert them into MPEG2 instantly in realtime.

Thus, in theory, it should also possible for any "DV to MPEG2" encoders (such as tmpegenc) to do the same in realtime rite? Moreover these encoders do not have to capture the video while encoding them, making their jobs far easier and faster.

My question is...why are these encoders taking so long just to encode these DV files into MPEG2? Are there no realtime or faster-than-realtime encoder in the market? In fact, I find that it is faster to do double work by exporting the edited DV files from my computer to DV camcoder, and re-capture them back into the PC as MPEG 2 using Sonic myDVD! This shouldn't be the way rite?

Just another VCD to DVD hobbist.

[abm100]

It's all about quality. I have a set top box DVD recorder that records in real time (obviously), but there is special hardware to do it. From what I read, SonicDVD doesn't do as good a job as encoding as Cinema Craft (CCE), MainConcept, TMPGEnc, etc. I use CCE Basic and it encodes 1-pass faster than real time. I have an XP 2600+. I do 2-pass VBR for quality purposes.

[bhwong]

I tried TMPGEnc and the MPEG video it output became blurred. At least Sonic can output sharp video clips. Is there something wrong I did with TMPGEnc?

Moreover, TMPGEnc encoding seem much slower than Sonic too! I'm using Celeron 2.4GHz. hmm....weird...maybe I should invest on a DVD recorder too....

Just another VCD to DVD hobbist.

[guns1inger]

I haven't used sonic, but I have used tmpgenc and mainconcept. tmpgenc can produce good output, but it is very slow. I also do not likes its handling of DV source files. Mainconcept is much faster, can do realtime encoding of DV to mpeg-2, and produces much better output than tmpgenc. There are two things I do not like about direct to mpeg capture.

1. mpeg is not a good editing format. Things are looking better with some of the ditors, but is was designed to be a delivery format, not a capture and edit format. It is also much lossier than DV, so when editing, you risk greater artifacts.

2. Direct to mpeg encoding is a single pass encode. Be it CBR or VBR, it is still a single pass. I always encode 2-pass VBR.

Solution - transfer as DV, edit in a good DV editor (I use Vegas) that has a good mpeg-2 output facility (Mainconcept), and everything is sweet. This is certainly no slower than your method of transfering back to tape, and will produce better output.

[bhwong]

The problem with editing AVI or MOV (DV encoded) files is that the rendering process takes far too long. The fastest DV editor is still Apple's iMovie, because it make use of DV stream instead of standard AVI or MOV files. Is there no other DV editors that handle DV stream, especially on the PC platform?

> 2. Direct to mpeg encoding is a single pass encode. Be it CBR or VBR, it is still a single pass. I always encode 2-pass VBR.

Well, the advantage of 2-pass VBR is quality at minimum storage space. But since most of my DVDs are less than an hour, I don't have to save on disk space. Thus, I'm going for time saving and hopefully, quality as well.

The MPEG2 clip captured by Sonic MyDVD realtime 1-pass CBR is virtually of the same quality as of DV (At maximum quality setting of 9MB/s). In fact, I'm surprised to find that the quality TMPGEnc produced using 2-pass VBR is inferior to myDVD 1-pass CBR! So I can live with a 1-pass CBR, wasting lots of storage space in exchange of time saving and...quality.

> 1. mpeg is not a good editing format... you risk greater artifacts.

Yes, I agreed especially when you re-render the MPEG file again. But when you are doing a simple split and join function, there shouldn't be any re-rendering at all. At most, the re-render part will be adding of a single I/key frame after the splited/joined section.

One of my fav MPEG1 editor is iFilmEdit, because no matter how much you split and join MPEG1 files, there is no drop in quality because iFilmEdit will never re-render anything. This also mean that iFilmEdit can "encode" MPEG files as fast as your harddisk transfer rate! In seconds instead of hours!

How did iFilmEdit manage to do that? Well, because it isn't a frame accurate spliting and joining tool. When you cut a section, iFilmEdit will find the nearest I/Key frame and cut that area instead. If you want speed and quality over accuracy, iFilmEdit is just amazing!

But now that I started to author DVDs instead of just VCDs... Suddenly, I found myself lacking of all these superior MPEG1 tools for MPEG2.

So does iFilmEdit-similar editor exist for MPEG2??? If not, how about just a realtime encoder?

Just another VCD to DVD hobbist.