Topic: Glitch every time I render

[yousef]

I've got a project in Vegas: 1x 720p cam (.m2ts), 1x 1080i cam (.mp4) and an audio track from my M10.

I've done a couple of songs from the same night and all is well but on this particular one, every time I render to MPEG2 (NTSC widescreen - tried both 'program stream' and 'DVD Architect stream' options), I get a visual and audio glitch at 1min15sec. The glitch occurs during a segment from the mp4 source.

There is no glitch in evidence when I play the project through in Vegas and the glitch doesn't appear when I render to .avi. And yet every time I render an MPEG, there it is in exactly the same place.

You can see the video (and glitch) here: http://www.youtube.com/watch?v=qebObpHuqjA

Any ideas what I'm doing wrong here?

[coloartist]

I am not seeing a glitch at 1:15 ?

[hellawaits77]

I am not seeing a glitch at 1:15 ?

I don't see the glitch, either.  Quality is great!

[yousef]

This is too strange...

I first noticed the glitch when I checked the video at Youtube - so I checked my file and found it was present there too. It's been present on every re-render since and yet  now, when I check on Youtube, the glitch isn't there anymore...

And yet it's still there on my MPEG2 renders on my PC.

What's going on? Can Youtube detect this sort of problem and correct it after uploading? I'll have to upload my file somewhere and see if it's still glitchy on others' computers.

[shoestringconcerts]

sounds like an issue with your video player not the render

[willndmb]

i had a glitch (picture froze) at 1:25 and thought you put the wrong time but then i played it back and it was fine
what is the glitch you were seeing at 1:15?

[yousef]

On my files, the picture jumps up a little and the audio crackles for a moment at 1:15.

The Youtube clip used to do exactly the same thing - I swear! As I said above, it was on Youtuve that I initially spotted it...

I do wonder if it's just my machine/media player. I'm going to check the clip out tonight on a couple of different PCs and if it's still present I'll upload the clip somewhere for others to have a look at.

Thanks to all for your input.

[beatkilla]

Just a guess but one of your clips is interlaced and maybe you did not properly deinterlace it.When watching interlaced footage on a computer display there will appear to be numerous glitches.Try deinterlacing your 1080i footage.

[yousef]

Just a guess but one of your clips is interlaced and maybe you did not properly deinterlace it.When watching interlaced footage on a computer display there will appear to be numerous glitches.Try deinterlacing your 1080i footage.

Interesting...

I've tried rendering with a few different settings based on the interlacing and am getting similar glitches but in different places.

How do I properly deinterlace the footage to avoid this?

[yousef]

This is driving me absolutely mad...

I'm now trying to render a different song from the same night but am getting another glitch, this time during a shot from the 720p footage.

I'm sure this issue has its roots in the media/project/render settings triad.

I start the project by matching the project settings to the 720p footage and when I render out I go for:

MPEG2
NTSC widescreen, 720x480, 29.9p, 16:9
I-frames: 15, B-frames: 2
Profile: main, level: main
Upper field first
Video quality at highest setting
Variable bit rate, two-pass

I've also tried adjusting the project settings to the NTSC template before rendering but I'm still getting glitches. (Full resolution rendering quality set to full and deinterlace method: blend fields).

Is this something to do with using variable bit rate?

Any pointers would be very welcome.

EDIT: Just realized that I'm rendering to an interlaced format - will try again in progressive

FURTHER EDIT: Nope, just rendered to progressive and got a glitch that involved the bottom third of the screen jumping to one side momentarily during a shot from the 720p cam

[beatkilla]

Try changing your PROJECT Properties to 1280 x 720.
Change the field order to NONE.
Change the deinterlace method to INTERPOLATE and set the full resolution rendering quality to BEST.
And also uncheck the box that suggests something like Automatically change media to better match project settings!

Your render settings are OK as is.Although i personally thing 2 pass is a waste of time.I would use a  CBR of 6,000,000.Unless you need more time on the disk.

[yousef]

Many thanks - I'll have another try with those settings this evening...

[yousef]

Sigh.

I tried with the recommended settings above but have got three glitches: all like the one described above - a momentary shift in the bottom quarter/third of the screen accompanied by a blip in the audio. This is always during the 720p cam footage.

One thing that might be influencing this is that the 720p cam is a Panasonic ZS3 which labels its footage with an incorrect 59.94 fps flag but I thought I could get round this by checking "disable resample" on that track.

Also, the original glitch was on the 1080i cam footage, so I'm not sure it this is a red herring.

Also wondering if the fact that the audio is affected at the same time is a clue to what might be going on.

Your further thoughts would be much appreciated.

Looking around online it seems that this is a fairly common problem with Vegas (and particularly Platinum 10) - I'm going to try one recommended workaround that suggests rendering to avi and then converting that to MPEG.

One last question while I'm here - if I want to render a SD version of this footage for a DVD copy, I am doing the right thing my rendering to MPEG2, aren't I?

[beatkilla]

I have never heard of this type of error before. When rendering are you using the camera audio or seperate?Are you using plug ins or vst on the audio or video tracks? How are you viewing back the rendered files and is the glitch always in the same exact spot ? Have you defragmented your hard drive lately? Also i would use smart resample on your clips.

[shoestringconcerts]

my new guess is some problem with the way your mpeg2 codec is installed, try rendering as an mp4 or some other codec and see if that has glitches

try uninstalling and reinstalling Vegaspro, i had to do that once before when Vegas would not render mpeg2 clips at all