AR wrong when importing this AVI

[terrypin]

I've raised this in the Magix MovieEdit forum, as at first sight it seems to be a bug in my NLE, which is MovieEdit Pro 14 Plus. But I wonder whether any of the experts here can offer any advice please?

The problem had me baffled until I realised that it's because MEP apparently can't do simple arithmetic.

I have an AVI file (a 3 minute download extract of a TV broadcast) which is 640 x 352. I quickly made and burned a DVD from it with a program I use occasionally, ConvertXtoDVD, and that's fine.

Then I thought I'd make another DVD using MEP 14 and take this opportunity to try MEP's menu-making and burning features for the first time. But I never got beyond the import of the AVI. Instead of a wide image I had what looked like a 4:3 squashed-in image in the monitor. On import, MEP repotrts:

The active movie has a resolution of 720x576 (16:9), 25.00 fps.
The file "HarryPaullanguageCoaching.avi" has a resolution of 640x352 (4:3),25.00 fps...

But 640x352 is an AR of 1.818, very close to the 1.778 of 16:9. It's nowhere near being 4:3.

ConvertXtoDVD didn't make the same mistake. And GSpot reports the AVI has a
Pixel Aspect Ratio ("SAR"): 1.818
Display Aspect Ratio ("DAR"): 1.818

So any idea why MEP should do this please? I'm guessing it's one of many bugs I've found over the last few months.

More important, any suggestions on how I might correct this somehow please?

--
Terry, East Grinstead, UK

[jagabo]

The AVI container doesn't support display aspect ratios. Individual codecs do but they are internal to the codecs. Programs have to be specifically written to parse the information from the codecs -- and most programs do not. Because of this most programs assume square pixels when importing AVI files (DAR = SAR) but will let you override the DAR in case they get it wrong. Look to see if you can override the source DAR in MEP.

[terrypin]

Many thanks, understood.

Turns out that MEP's Object Properties actually lets me change the AR. It was showing 4:3 and after changing it to the 16:9 option all now looks well.

--
Terry, East Grinstead, UK

[terrypin]

Hmm, that was premature. While the aspect ratio is correct, the audio is now out of sync. Both while playing the AVI in the monitor and playing the resultant DVD MPG externally.

Yet the AVI plays correctly in other players I tried.
- VirtualDub
- WMP 9
- MediaPlayer Classic
- VLC

And it's fine in MemoriesOnTV.

--
Terry, East Grinstead, UK

[jagabo]

VBR audio?

[terrypin]

Not any more, but ...

When I first opened the original (compressed) version of the AVI in VirtualDub I got
[!] AVI: Variable bitrate (VBR) audio detected. VBR audio in AVI is non-standard and you may encounter sync errors up to 3339ms when attempting to extract WAV files or processing the audio in Direct Stream Copy mode. Full Processing mode is recommended to decompress or recompress the audio. (bitrate: 131.4 ± 18.8 kbps)

I did indeed get that sync problem, so I re-saved the file using 'Full Processing' mode.

But that uncompressed file, the one now under discussion, is not VBR. And, as described, it is behaving correctly with every program I've tried so far - except MEP.

--
Terry, East Grinstead, UK

[jagabo]

Out of sync by a fixed amount over the entire video? Or does it vary?

[terrypin]

Hard to be 100% sure, but seems constant difference throughout.

However, both the aspect ratio and sync issues appear to be due to an MEP setting. I recently unchecked one of the 'import formats' in MEP, called 'Internal AVI Import'. If I re-enable it, load a new move and import the compressed AVI again
- It gets the correct AR
- Audio is in sync.

The reason I had unchecked it was following a discussion a few weeks ago in the MEP forum about why importing large AVIs (over 2 GB) were causing MEP to almost freeze up. A practical solution appeared to be to switch off that import format. MEP then uses the one called 'DV AVI Import module', and that way I successfully worked with files of over 2 GB.

Presumably if this AVI file under discusson was over 2 GB I would be back with those problems. BTW, this clip is only 1m40s long but is still 1.7 GB!

So looks like I can't have my cake and eat it...

--
Terry, East Grinstead, UK