Nested projects lose interlacing (i.e., become detinterlaced)

[Steve Rhoden]

Seems that bug was never addressed initially at all Meyer.

Steve Rhoden
(Cow Leader)
Film Editor & Compositor.
Filmex Creative Media.
1-876-832-4956

[John Meyer]

Seems that bug was never addressed initially at all Meyer.

I’m not sure what you mean by “initially.” Are you saying that other people reported it?

I did not attempt to see if this bug only manifests itself when rendering to MPEG-2, but I suspect it happens with all codecs. If true, this means that everyone who has used nested interleaced video in their projects for the past several years has been producing compromised video.

[Graham Bernard]

Could it be that “bug” is restricted to AVCHD? I’m using my Canon XF300 HDV footage, 1440x1080i UFF MPEG.

Using HDV, and wanting to reassure myself, I followed the testing. Phew! I don’t get this change to deinterlace. I’ve checked the MPEG through G-Spot and MediaInfo and of course VP11 (B683) and they all say interlace.

I went a stage further and forced UPPER to LOWER field for the MPEG and they all came back LOWER, and again the resultant MPEG came back correctly switched to LOWER.

Cheers

Grazie

[John Meyer]

Unfortunately, you can’t rely on G-Spot, Mediainfo, or any other such tool, to test the actual field order. They only tell you how the field order flag has been set (which is only available for some video codecs) and that flag can be set, and the fields can actually be different from what the flag claims. I am quite sure that is what is happening with your MPEG-2 files.

Instead, you actually have to use a tool which can look at one field at a time, and then use your own eyes to see if you have motion (other than the up/down “bobbing” you get because of the spatial displacement between fields) between fields.

Now, to actually respond to your thought that the problem only happens with AVCHD files, while I thought it exceedingly unlikely that the bug would be correlated only to AVCHD files, I went ahead and did the test just now, but using HDV files from my Sony FX-1.

I got the same exact result: there is no motion between fields (i.e., it has been deinterlaced) Just to be complete, I then re-did the test using Vegas 7 and HDV files, and it did everything correctly, and the resulting MPEG-2 file retained the interlacing.

If you want to upload a sample MPEG-2 file that has been created from a nested file that in turn uses interlaced footage, I will be glad to test it. Alternatively, you can use the procedure I outline in the Sony forum for how to deconstruct a video into fields so that you can determine whether you have interlaced or progressive footage, and also be able to tell whether you have a field reversal problem (which will show up as a “back and forth” motion when you view the individual fields, one after another). Here is a link to that post:

https://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=809593

I still prefer to frameserve out of Vegas into an AVISynth script that simply contains a “separatefields()” command because it is easier to avoid mistakes (the procedure above requires that you do everything exactly as described), but either method will work.

[Graham Bernard]

John, using your methodology I reproduce this too.

This is on VP11 B683. It may have been fixed in the newer B700/701 though.

OK, using your “Interlace Checking” – the doubling of the project frame rate from 25fps to 50fps – I started off by checking freshly captured, interlace media: 1440x1080i MXF MPEG., UFF, and sure enough, using the ALT key technique, I could definitely see the the expected movement ARROW by ARROW. So I knew now what to look for.

Have you got any further forward with informing the developers?

Cheers John,

Grazie

[John Meyer]

I haven’t yet installed the latest patch for Vegas 11, but I doubt that it was fixed in that release since I didn’t send my support ticket to Sony until about a week ago. I got involved with this at that time because I was helping someone, via email, who posted in the Sony forum, (where I refuse to post anymore, but that’s a story for another time).

So I only became aware of the problem at that time.

As far as your question about getting a response from Sony I of course haven’t received any reply from Sony and I don’t expect to until around Christmas. It is really sad for everyone to see their support decline so much, but it is especially tough for me because I used to have a direct line to the development team, and was able to help them discover and track down quite a few bugs over the years.

Since this particular bug has been in the program since at least 10.0, it means that every single project that anyone has done with nested VEG files that point to interlaced media has had that project degraded and compromised.

[Graham Bernard]

Sure, understood.

However, I just repeated your methodology in VP12, and there I AM getting frame progression. Maybe it’s been fixed?

Just to confirm:

1] In a Parent Project I placed a Nested Child. This is ALL the same Media.

2] From this Parent I rendered out an SD MPEG.

3] I imported that same SD MPEG into a brand new Testing Veg, and did your test for Interlace and got frame progression. What I witnessed was frame by frame progression, and that’s within this Progressive Veg.

Could be it HAS been fixed? I’ll do another repeat of your Methodology to check.

OK, NOW, and here’s what’s interesting as SOON as I placed the MPEG into the “testing” veg Vegas asked IF I wanted to match the Project to the importing MPEG, I said YES – and maybe just maybe that right there is the difference? Of course I then did the PAL Doubling frame rate and switch to Prog and NONE.

Interesting.

Grazie

[Graham Bernard]

I thought to check again the VP11 Testing Veg and well, John, here’s a turn up for the books, and no mistake: That which I COULD repo in VP11 B683, I now CAN’T!

I’m Keying through the MPEG interlace clip in the same testing VEG Progressive and 50fps PAL, I am now getting frame progression. Is it at all possible that having used the methodology in VP12 this could have kicked-started VP11 B683 to behave correctly?

Rechecked: To check this again, I started a brand new fresh “checking” veg: 50fps (Double PAL) Field Order NONE; Deinterlace – NONE; plopped in the MPEG2 SD PAL 25fps Interlace and again keying through AND getting frame progression.

Bizarre . . .

Grazie

[Nick Hope]

I checked here in 10.0e 32-bit and no problems. All is as it should be.

[John Meyer]

I did some more testing this morning. First of all, here is a link to a very small set of files that will let you reproduce the problem:

4730_nestedprojectbug.zip

This was done in Vegas 10.0e.

I did find that the problem does not happen when using either PAL or NTSC DV AVI files (i.e., for NTSC, 720×480 interlaced SD video). Also, it is possible that the preview resolution is affecting things. Normally this would not affect the rendered output, but perhaps with nested projects it matters. I had the preview resolution set to Preview Auto when I did these tests.

So, if you download the small zip file, and open the “Project uses nested HDV interlaced video (Vegas 10).veg” file, and then render to an NTSC Widescreen MPEG-2 file using the DVD Architect NTSC Widescreen template, you should get a progressive (rather than the expected interlaced) MPEG-2 file.