Blinking text gremlin

[Sam Houchins II]

Text is blinking.
I've observed that some generated text blinks if the segment is simply stretched instead of actually lengthened by increasing its time properties.
But this element blinked away from its stretch-repeat point.
And I can't even find it on the edit timeline, only in the render.
This is the first time that I've rendered at "best". Maybe more wonky things show up at that setting that just blend into oblivion at lower render settings?
update: can't recreate it when pre-rendering it. Will see if it shows up in re-render.

[Sam Houchins II]

Then there's this text blink in render but not present in the timeline.

[Sam Houchins II]

this time a "highlighted" area created by a mask on a solid color event. The highlight blinks in the render but nothing on the timeline to indicate a cause, and thus nothing I know to correct or to do to avoid it yet.

And a few sec later another blink with 2 highlights in render, but nothing on timeline.

Worse, a few secs later, the solid "highlight" element pops out full screen for a frame, ignoring the mask in place that's working for the previous and subsequent frames.

[Christopher Young]

If these are still images I wouldn't be stretching them I would try right clicking on them and selecting 'Insert/Remove Envelope/Freeze Frame at Cursor' at the second frame in of the still and then then drag the end of the still longer or shorter to the length you require. That may fix the problem as it doesn't have to do any interpolation or blending which is involved in stretching it just repeats the frame where the freeze frame is established.

Also check out 'Resample (video only)' in the Vegas help file because sometimes if you are stretching things the sampling mode can effect the renders. No rhyme or reason to it but sometimes 'Disable resample' will fix these sorts of rendering anomalies.

The sampling options can be found under your Project Properties/Resample Mode.

Chris Young

[Sam Houchins II]

In these cases, the glitching elements are generated media - either text, or solid color with mask - overlaid onto a still image overlaid onto video
Same recommendation?

Glimmer of hope.
There's another longer section of generated solid color media used with a mask for highlighting sections, and selectively pre-rendering that section 3x resulted in blinking glitches in 3 different places.
This after freezing each still image 2 frames in, and disabling each of their resampling.

The 4th selective pre-render had no glitches, but used
MAGIX AVC/AAC MP4 Internet HD 1080p 29.97 fps (customized to Best)
instead of
MAGIX AVC/AAC MP4 Internet HD 1080p 29.97 fps (NVIDIA NVENC) (customized to Best)

Will have to see if this improvement pans out on other (p)re-renders

[Christopher Young]

May I make a suggestion Sam. One thing I NEVER do is to use a Long GOP codec on any event that requires extensive manipulation or generated media. Generated media is an invention of something that doesn't exist. When creating something from scratch that doesn't exist the creation of this really requires you to start with 100% of data in every frame you create from the get go. Using Long GOP codecs for this type of work while it can work in many cases often in complex computations it is generally way beyond the algorithm capabilities of decoding and re-encoding of Long GOP MP4.

There is too much information missing in the file to reconstruct correctly. Like there is only one 'I' frame containing all the image information every 12 or 15 frames depending on whether it's 50 or 60Hz. Try humoring me and just try rendering one of your segments with the problems to one of the Inter Frame codecs below. Those segments whether they be rendered out or prerendered will obviously be much larger, because they have 100% of the data in each frame. If drive space it not a major problem this is generally not an issue unless you are using a slow external USB drive. Drive speed can have an impact on playback.

You may find that this fixes some of your issues. Give it a try and post back. There is normally an answer to every problem in editing.

Chris Young

[Sam Houchins II]

Thank you for the suggestion. I look forward to trying that tomorrow, because on early review, it looks like some blinking is showing up with the MAGIX AVC/AAC MP4 Internet HD 1080p 29.97 fps (customized to Best) too.
Are you suggesting to render out the segments as indicated, and then add the rendered segments back to the timeline to be rendered into the whole MP4?
Thanks again!

[Christopher Young]

Yes Sam you could render the segs out and then import them back in to drop them on a track above so that they get rendered into the final production. I've done it as described above but have also used pre-renders. I go down the final edit timeline and pre-render the questionable segments to an Inter Frame codec. Anywhere I have done major moves, graphics, generated text, resizes etc. If I want to check the results out first then usually I'll render some of segs out and if all good do the rest as pre-renders. Just remember if you do pre-renders and change any timings on the timeline you can throw things out.

Chris Young
Sydney

[Sam Houchins II]

ok /sigh
I rendered a relatively small segment separately, uncompressed, and still ended up with a blink. I was shocked at the 3GB file of a few sec clip, but grateful that it only took a minute to compile.
> I went to trying to selectively pre-render troublesome segments (back to using the faster, smaller NVIDIA option), and now I'm getting large sections of those pre-rendered segments that freeze. Audio continues normally in the pre-rendered segment, but the video motion stops for a 3, 4 second block within.

I haven't taken the time to share any of the actual project .veg because I don't know how, and I was trying to hurry and get this out, but I'm spending too much time going in circles.
Can you advise me how to share a segment of an 1-1/2 hour timeline?
I'm in the process of deleting everything before and aft, and then saving it with clipped media. Am I on the right track?
Thanks.

P.S. method to try to share .veg file resulted in an 81.3 G folder, with the source vid not clipped :-(

[Christopher Young]

Sam. I would suggest as you say deleting everything before and after a particular problem segment so you end up with a short little timeline of your problem area then use the 'Save As' with a NEW NAME and select the 'Copy media with project' box which will take you to the 'Copy media options' check box where you would select 'Create trimmed copies of source media.' Leave the default of 'Extra head and tail' at 2 seconds. That should give you a smaller file. Zip all together and then upload.

If you don't have an FTP server you could use Google Drive which will give you 15GB of space for up uploads and or Microsoft OneDrive which gives you 5GB. Hopefully you could use one of those if the problem segment isn't over 15GB... hopefully! Then post a link to the download or if you don't want the download in the wild just PM me the link. No promises but will see if I can achieve a result. If I can I can then re-upload a VEG file with any solutions I come across.

Ciao
Chris

[Sam Houchins II]

This is ridiculous.
I know I haven't gotten to try again to create a copy of the veg file, so the help is limited.
I'm down to 8 segments with generated media that's subject to rendered glitches, so instead I took the time to selectively pre-render each of the 8 and try full rendering anew. Some segments took up to 5 attempts to selectively prerender a segment until the prerender itself didn't have a glitch in it.

Well, it turns out that selectively pre-rendering a segment is no guarantee that a glitch still won't show up in the full render.

[Sam Houchins II]

Whether selectively pre-rendering, or rendering to another track or file, Intel based, NVIDIA, or uncompressed - there was no guarantee that a glitch wouldn't happen in the same segment. But come to find out, the glitches wouldn't happen at the same frame.
So the "solution" ended up being to simply take two renders of the same segment with glitches at different points, and splicing their good parts together.

Render in full.
Review render and find glitched frames.
Re-render those segments and splice their none-glitched parts in place of the full render's glitched part.
Render in full again.
Archiving this project for now, because I've got others to get done. I'll be looking for ways to implement some of the ideas during this next edit in anticipation of generated media instabilities.
Thank you for sharing your experienced tips and tricks!