Why is TMPGEnc deinterlacing when I tell it not to?

[euromuffin]

I hope this has a simple answer. I am downsampling a DVD quality MPEG-2 file using TMPGEnc Plus 2.5. The source file is at

http://members.rogers.com/norcent_dp300/input.mpg (1.8 Mb)

The created file is at

http://members.rogers.com/norcent_dp300/output.mpg (1.4 Mb)

Here is a frame from the source file

http://members.rogers.com/norcent_dp300/input.bmp (0.6 Mb)

and here is the corresponding frame from the created file

http://members.rogers.com/norcent_dp300/output.bmp (0.6 Mb)

Clearly the source frame is interlaced, but the converted frame has been deinterlaced and the fields blended. Why is this happening, since I think I've configured TMPGEnc correctly not to deinterlace? Here are the first three tabs in my settings dialog

http://members.rogers.com/norcent_dp300/tmpgenc1.jpg
http://members.rogers.com/norcent_dp300/tmpgenc2.jpg
http://members.rogers.com/norcent_dp300/tmpgenc3.jpg

Thanks in advance for any suggestions.


Euro

[txpharoah]

Straight TMPGenc without frameserving?
(As in, you opened the file in TMPGenc?)

Scratching my head too... odd...

[euromuffin]

Hi txpharoah,

Yep, straight TMPGEnc, no frameserving.

Euro

[txpharoah]

This may be killing an ant with a shotgun...
... but try to reinstall TMPGenc. Is this a good (new) version or a buggy (old) one you have?

[bbb]

If you go to Tmpgenc's Deinterlace filter, you will see that even if you choose "None," the preview window is already deinterlaced. Therein lies the problem.

The reason is because you have a MPEG2 codec installed that automatically deinterlaces (blend) all MPEG2 files and this is what Tmpgenc sees (Tmpgenc is not designed to open MPEG2 files but will if a MPEG2 codec is installed).

To get Tmpgenc to see the file as interlaced (and encode as interlaced), open your MPEG2 file with DVD2AVI. Then save as a project file. Open the project file in Tmpenc. Now, when you go to Tmpgenc's Deinterlace filter and choose "None," the preview window will now be interlaced.

So, in short --> Use DVD2AVI to open the MPEG2 files you want to encode as interlaced.

[txpharoah]

If you go to Tmpgenc's Deinterlace filter, you will see that even if you choose "None," the preview window is already deinterlaced. Therein lies the problem. The reason is because you have a MPEG2 codec installed that automatically deinterlaces (blend) all MPEG2 files and this is what Tmpgenc sees (Tmpgenc is not designed to open MPEG2 files but will if a MPEG2 codec is installed).

Good call. I see this now.

So EURO, what is the MPEG2 codec in TMPGenc? Any way we can get a screen cap of your environmental settings.

To get Tmpgenc to see the file as interlaced (and encode as interlaced), open your MPEG2 file with DVD2AVI. Then save as a project file. Open the project file in Tmpenc. Now, when you go to Tmpgenc's Deinterlace filter and choose "None," the preview window will now be interlaced. So, in short --> Use DVD2AVI to open the MPEG2 files you want to encode as interlaced.

Don't assume he's getting this from a DVD. Sounds like he's opening a file of his own, whereas this won't work. Fixing his MPEG2 codec is the key here. I like the PowerDVD MPEG2 codec (Cyberlink) and the LSX Suite (Ligos) codecs.

Show us what you have, and we can work from there.

[euromuffin]

Excellent! Thanks for your help guys.

bbb, the DVD2AVI frameserve works great! Interestingly, DVD2AVI doesn't produce a wav file I can mux with the frames when I encode (even though I have "Decode to WAV" selected and the audio format is identified as MPEG Audio) but that's okay - I can just use the original mpg file for that.

txpharoah, turns out the Cyberlink codec *is* the MPEG2 decoder identified under VFAPI plug-in, and as bbb pointed out, it must be deinterlacing the input. And I too normally use DVD2AVI to frameserve vobs, but it works fine with mpg's as well.

Thanks again!
Euro

[DJRumpy]

Ensure your AUDIO | TRACK NUMBER option is set to a track # (usually Track 1) if your input is MPEG. If its set to none, then you will get no output.
Channel Format should be set to AUTO.
Dolby Digital: Set to Demux if you want AC3/MP2 (depends on your source). Set to Decode if you want WAV output.

[euromuffin]

Hi DJRumpy,

Track Number is set to 1 (I don't have a none option).

Output Method is "Decode to WAV".

I don't see any Channel Format options.

Also, under Dolby Digital Decode, I don't have the options you mentioned, only Dynamic Range Control, Dolby Surround Downmix, Pre-scale Decision (did you mean Output Method?) And besides, this menu should be irrelevant since I'm not dealing with a DD stream, right?

I am running DVD2AVI 1.77.3. Perhaps it's another version which has the options I'm missing, and which demuxes MPEG audio to WAV?

Thanks,
Euro

[DJRumpy]

I'm still using 1.76. It's the only version that works with AVISynth 2.x. I would give that version a try. If you can't find it here, look at www.doom9.org. It's one of the most stable releases for DVD2AVI.

It might also be worth your time to look at the stream info in the DEMULTIPLEX tab in TMPGenc | MPEG TOOLS. I'd be curious to see if there was more than one audio stream.

[euromuffin]

Thanks for the suggestion. I'll try it. And I know there's only one audio stream because it's my own capture. The demux stream info confirms this.

Euro