2.7 GB MPG2 file bloats to 5 GB when authoring

[wallmg]

Multipart Questions:

I am capturing MPEG2 352 x 480 off the TV with an ATI AIW 9000 Pro. I edit out commercials looking for cut points in VDub and actually cutting in TMPGencPlus using the Merge & Cut function. The file size ends up being about 2.7 GB in size.

QUESTION 1:
Why, when I go to author and burn the MPEG2 using Roxio 6 DVD Builder, does the program show the file size over the 4.7 GB mark and not able to fit on the DVD? I thought I was capturing in a DVD-ready format, going by the guides on the LordSmurf site. I even tried reencoding it in TMPGenc Plus (which took a ridiculous 16 hours) but the video looked worse and it still didn't fit on the DVD. What am I doing wrong?

QUESTION 2:
Why does the audio get out of sync with the video as the movie progresses? It is usually most noticable in the last half of a movie. It gets pretty bad toward the end.

Thank you to anyone who can help! I'm stymied.

Mark

[sacajaweeda]

What format are you using for audio?

[Bondiablo]

First guess would be Roxio is converting the audio to PCM or I think I remember something about Roxio only allowing 6000kbps CBR and it's converting the video to that. Try a different authoring program, check the tools section.

[wallmg]

Sorry ... I'm capturing at 48 (Mhz?) in PCM format. Bitrate is at a max of 4.

Is that not DVD ready format. Shouldn't it just stay the same size as the captured file when I go to author?

Mark

[Bondiablo]

https://www.videohelp.com/dvd

[wallmg]

OK, read it. Still don't understand what's happening. The info you pointed me to indicates that 352 x 480 is a valid MPEG2 size for DVD-video, but the chart at the bottom shows DVD (for NTSC) only at 720 x 480. It seems to be contradictory information.

If indeed DVD has to be 720 x 480, I guess that would explain the "bloating" upon authoring. Is the authoring program actually doubling the vertical (???) resolution, thereby doubling the file size?

[johns0]

352x480 is a dvd compliant resolution and changing the resolution doesnt increase file size,bitrate is what determines the file size plus if the audio is pcm that will take out a good chunk of space.

[wallmg]

Thanks for the info about file sizes. I'm still not understanding why my file size changes when I go to author it. The captured file (with PCM audio) is 2.7 GB. If I'm authoring with PCM shouldn't the file size be the same? Maybe Roxio automatically doubles the bitrate????? It only has three settings for encoding: High compression (rough cut); Low compression (optimized quality); and Automatic compression (with quality dependent on size of project and capacity of media).

I remember doing the automatic compression once on a similar sized original file and the quality turned out to be TERRIBLE. Can't you just skip the encoding since it's already a DVD-compliant capture? If so, can you skip encoding the video portion of a project if you have a menu, or does it have to "re-encode."

It's all TOO much to take in

[johns0]

Try tmpgenc dvd author and import your files into that,its more user friendly and wont convert dvd compliant files.

[wallmg]

I did download the trial version and was able to use it once before it expired. It didn't give me the full 30 days for some reason -- it was more like half that time. Anyway, that was the only success I've had so far. I would just like to try it a couple of more times to be sure that wasn't a fluke. Anyway, sounds like that's the problem. The compliant file is being converted and bloated. Thanks for the help. Now if I can get the A/V sync issue resolved ...

[johns0]

Try using another capture program like virtualvcr and for the files that are out of sync you can use an audio editor such as goldwave to either shrink or stretch the audio running time and also use delay if needed.

[wallmg]

I think the A/V is going out of synch after I edit out the commercials using VDub for finding commercials and TMPGenc for the actual Merge & Cut. I tried Womble for cuts (which is much easier) but I had the same results with it going out of synch. I guess I could go in and fiddle with shrinking and stretching the audio, but that would be excruciatingly time consuming and hard to get precise. A LOT of effort to just be able to have no commercials.

[FulciLives]

Just import the captured MPEG-2 video into TMPGEnc DVD Author and it will allow you to cut out portions you don't want. So you can trim the start and end points and removie commercials.

It is very easy to do this.

Sorry that your trail is over but this program is definately worth the money!

- John "FulciLives" Coleman

[indolikaa]

If you are capturing with an ATI AIW 9000 Pro (as I do for several hours per day) AND you are capturing in the default mode, you are capturing audio in MP2 audio mode.

The only way you can access PCM audio in MMC 8.x is to change the Video Format from MPEG-2 to MPEG-2 DVD. The standard setting of '48,000 Hz, 16-Bit, Stereo' is MPEG-1 Layer II audio and not PCM audio.

It sounds like what is happening is your audio is being transcoded into PCM by Roxio. I'd bet money on it.

MP2 audio averages about 244-256kbps, while PCM audio is 1536 kbps. The dramatic increase in your filesize is more than likely attributed to this.