Video editing oddity

[Tuck Pendleton]

Hi
I’m new to this forum and an absolute novice to video editing so go easy on me!

I’ve been using Free Video Editor v 1.4.53 to edit commercial DVDs I have ripped with DVD Shrink then converted to MP4 with DVD Converter Ultimate 4. It’s fairly basic but it suits my purposes pretty well.
Anyway, long story short, after editing lately the MP4 files are still displaying their original length in Explorer, despite the file size being smaller. i.e. If I’ve removed 10 minutes from a 30 minute video that was 1.5GB, it will display as 1GB in size but still 30 minutes in length.
This has caused a slight issue when burning the files to DVD using Freemake Video Converter as it calculated the total length incorrectly and down-scaled the quality accordingly.


I’d be grateful if someone could explain, and suggest a fix for this anomaly.
Thanks

[netmask56]

First post a MediaInfo file report on the MP4 before editing and one after editing. Then we can see whats going on. Use Text mode and copy and paste if not familiar with MediaInfo

[redwudz]

Try MediaInfo for reading the info on the file instead of Explorer. But the problem may be that the original header
for the file was preserved and that's what Explorer is reading.

And you are burning the edited files to a DVD disc as MP4 data?

And I would edit the ripped DVD files instead of the MP4 and you might have less problems. MP4 does not edit well,
same as MKV or other highly compressed formats.

If you didn't need to edit, a decrypter program and VidCoder to MP4 would be a lot simpler.

But other members may have better suggestions.

And welcome to our forums.

[DB83]

I'll try to go easy on yah. But something has to be said. There is little to no point in converting a dvd(mpeg2) to mp4 and then reconverting that mp4 back to dvd.

For all I know, you have lost quality in the original conversion and even more in the 2nd conversion. Even without the issue of incorrect video run-time.

I'll suggest another workflow. Not familiar with your choice of editor and converter but it should handle it.

1. Rip the dvd - with no shrinking.
2. Convert the vobs to an intermediate lossless format such as lagarith.
3. Edit the converted video now in avi format. And resave as lagarith avi
4. Make the new dvd with avstodvd.
5. Burn the files so created with imgburn.

If you can not create a lossless avi format then just use vob2mpeg to create a mpeg file and edit from there. But still save a mpeg2 and NOT mp4.

Mentioned below but avidemux is a pretty good basic editor if you just need to remove some minutes from a video. You can then resave that video (mpeg2) as a stream copy without any further loss of quality.

The basic explanation for your problem is AFAIK file-header corruption. A quick fix could be to re-save that mp4 with avidemux or mp4box but I would not do that for the reason I already mentioned if you have any regard for quality.

[Tuck Pendleton]

Cheers for the replies guys.

I've uploaded text files from MediaInfo as requested. 'Demons' is prior to editing; 'Demons cut' afterwards, obviously.

Hopefully you can make more sense of them than I can.....

[jagabo]

If you're only doing cut and paste editing (no filtering) and can live with cuts on key frames (about 1/2 second apart on DVDs) you can edit the video losslessly with MPG2CUT2 then author a new DVD losslessly from the resulting files. The safest procedure:

1) Rip with DVD as a VIDEO_TS folder with Decryptor or DVDFab.

2) Optional: Remux to an MPG file with VOB2MPG. 95 percent of DVDs don't require this step. But some will.

3) Cut/Paste the MPG file (or VOB files if you skipped step 2) with MPG2CUT2.

4) Author the resulting MPG file(s) to make a new DVD, and burn with ImgBurn.

[DB83]

I am no expert here but the issue could be the choice of codec ie ISOM. Obvious question time. Have you played that edited file to check its runtime ? Mediainfo is not perfect and that could also be fooled by this ISOM.

But there are also other issues with that edited file. So you start with a 720*576 4:3 - the original source may not have been 4:3 (Probably 16:9)

Then you end up with a weird frame size of 1024*768. Yes, that is 4:3 but the vertical size has altered with no overall benefit. And convert that back to dvd and you lose that anyway.

[Tuck Pendleton]

Hi guys

I've kind of sussed out a work around by re-saving the files with Avidemux. Bearing in mind we're dealing with a TV show made in 1990, it's hardly HD quality anyway. I'm going to watch them back on my DVD player soon and if the quality issue bothers me I may get back to you for an idiot's guide for what DB83 was suggesting.

Thanks for the help.

[Tuck Pendleton]

Actually, 2 quick questions before I leave this for now:

1. All the software that has been recommended (DVDFab, VOB2MPG, lagarith, avstodvd, MPG2CUT2), are these freeware or would I have to buy a full version to do what's required?
and
2. Assuming I am able to navigate my way through one of the processes, would have to burn to a DL DVD if the files have never been shrunk?

Cheers

[DB83]

When you re-read your post as above you will see that all 'software' is now in red and these are actually links to the downloads.

From your list, only DVDFab is payware although I believe the ripping part of it remains free so you can download that and rip to your heart's content. Lagarith, as you will read, is not a software but a codec just as your ISOM.

You are working under a false assumption. Ok maybe your motive in using dvdshrink is to fit what was on a DL DVD on to a single-layer disk. But then you ruin that by re-encoding/editing mp4 and the various frame re-sizing as already written about.

File size is all about bitrate and what maybe 4 gig on a mp4 may not fit on a SL disk even after shrinking.. Easier to think in terms of hours. A SL disk can comfortably fit 2 hours of video on it. So work in those terms and just let avstodvd work its magic to create your dvd.

If you have shrunk then work, as suggested, in mpeg2 with stream copying so you are guaranteed that it fits on a SL Disk.

I did previously suggest that you used avidemux so glad that the remux from there fixed the original issue. But I also hoped that you used stream copy otherwise your video has been re-encoded again with even more loss of quality.

None of this is meant as a lecture since we all have to learn and much can be confusing from the off.