Multi-Sequence Timeline Freezing

I had the same problem (with the multi-cam playback monitor view only - single cam playback window was fine without the following adjustments), until I turned my color grading layer off. I also reduced the sequence playback settings. This eliminated my issue. The color grading adjustment layer seemed to contribute significantly to the issue. I simply turn the multi-cam view off when and work with a single view in the playback monitor when working with the color grading adjustment layer on. Hope this helps someone out there!

Yes, we're both saying that there's an issue with your original media. And there are several ways to work around the problem.

First, what is long-GOP? GOP is "group of pictures." In reality the files are only a complete, actual frame of video image every 9 to 30 or in some cases, up to 120 frames apart. These frames are called ' i-frames ' .

But what is in-between the i-frames? Isn't there video there?

No, there isn't actually video in-between those i-frames. There are only data-set charts ... tables of data, listing the pixels that have changed since the last i-frame, or that will change before the next timeline, or ... both.

So, to display most of the actual video frames of your clip, the computer has to:

• find the i-frames on either side of any specific frame,
• then from the data sets of the frames between the i-frames and the current frame, rebuild every frame in order to properly compute what the image pixels for "this" frame are supposed to show,
• store the rebuilt frames in RAM or cache files ... and finally ...
• play back the video.

Why do standard video players not have problems with long-GOP playback?

Simple. Because they are simple. There's nothing going on besides playing back the file. 

An NLE ... non-linear editor ... is a vastly more complex beast in operation. Several orders of magnitude more complicated. And therefore takes a ton more computer processing to operate. Why?

A player simply takes one video file, and plays it. No other computations involved.

An NLE takes bits of video from any number of clips, puts them in visual order as set on the timeline/sequence, adds any effects you've chosen and apply them separately to each image, and then gives a playback.

So this is different from video files that aren't long-GOP?

Yea. Codecs like ProRes, DNx, Cineform and others, may apply compression per frame ... but every frame is there completely in the video. No other frames are needed for the computer to present that frame. Only a bit of decompression.

How do I get around long-GOP playback problems?

There are several different ways. Pick which one works at the moment. One option is of course to shoot the original video using i-Frame codecs ... intraframe ... where all clips are a complete frame. Skipping the long-GOP thing entirely.

But for where you already have long-GOP, or can't avoid it, there are options to help playback.

1.  Before importing into Premire, transcode to ProRes or DNx or Cineform in say HandBrake or Cineform. Or MediaEncoder. The files will be much larger, but will work better for editing and exporting. As you can re-create them any time, after you're done, dump the t-codes and keep only the original, smaller files.
2. Import the H.264 into Premiere, but then select them in the Project panel, and have Premiere make proxies. Using the ProRes options, preferably. The proxy files will probably be bigger on-disc than the original files, but they'll play back like butter.

I'm still very confused by what is going on here. I'm not very savvy with understanding 'long GOP' or 'non-performant' footage. I'm more looking for a solution to speed up my workflow so there's no 5-10min lag with my playback.

Are you suggesting there is something I need to do with my footage before I put in premiere to make sure everything runs back smooth?

All my proxies are functioning properly & I have also successfully restarted my program, deleted all cache, & even put files in a new project but I'm still having the same issue. 

I appreciate any further insight you all might have to improve this issue.

The media is coming from files that I copied from an external hard drive onto my desktop (internal hard drive). 

Long-GOP is why he said it's non-performant. Very few frames are actually complete frames. Most are only part of the image with some of the image having to be computed from bits and pieces of another frame up to 30 or more frames in front of or behind that one.

ok, I will try to relaunch while holding down the shift key.. I have already deleted media cache.

What do you mean by the 4:2:2 10bit footage being a "non-performant"?

Hi @kalebk55570725,

Thanks for the message. While we await a community response, have you tried any troubleshooting steps. Try launching the application with the Shift key held down. In the Reset Options dialog box, choose to delete the media cache. See if that helps. If that doesn't work, ensure your proxies are functioning correctly. The 4:2:2 10-bit footage is non-performant and does need to be considered in all workflows, not to mention playback of multiple video streams. For sure, look into the proxy workflow moving forward.

I hope the community can assist you with a solution shortly. I apologize for the situation.

Thanks,
Kevin