Problem with multicam playback

[lvthunder]

I have 5 angles of footage of a figure skater routine.  They are all 4k.  Two Canon R5, Insta360, GoPro, and iPhone cameras.  I have made proxies for all the footage.  I have them in a multicam and I'm trying to watch it to select the angles to show.  There are parts where the video just stops playing or the fps is like 1 or 2.  I saw a YouTube video that said the audio was causing a problem so I clicked solo on one of the audio tracks, but that didn't help.  I'm on Windows and in Task Manager Memory is like 36% and CPU, Disk, and GPI are all under 6%.  Any ideas on what I can do would be appreciated.  The video is only 4 minutes long.

My Computer Specs

i9-13900K

64GB RAM

Nvidia Quadro A4000 video card

Samsung T7 connected to a Thunderbolt port for the video

[PaulMurphy]

What are the specs of your proxies? Specifically, their resolution and codec?

For optimal performance, you should use a mezzanine codec such as ProRes, Cineform, or DNxHR. If you're using ProRes, try adjusting the playback quality by clicking the Settings button (wrench icon) in the Program Monitor and selecting Auto-Adjust Multi-Camera Playback Quality.

Avoid using H.264 for proxies, as it is will create a playback bottleneck with multi-camera.

Additionally, if your iPhone footage is recorded in Variable Frame Rate (VFR), it may cause playback issues. Converting it to Constant Frame Rate (CFR) before editing can help ensure smoother performance.

[lvthunder]

I used the ProRes half-size preset when making the proxies.  So I guess they are around 1080p.  I'll check for sure when I get home.

[lvthunder]

OK when I'm in the Program Monitor it shows two images that are the same and I see the option in settings for Auto-Adjust Multi-Camera Playback Quality.  When I'm in the Source Monitor that's where I see all 5 and I can switch between them.  But that option isn't there in that wrench.  I attached screenshots of both of them.

[PaulMurphy]

It looks like you are currently viewing inside the multi-camera sequence. This does not enable the multi-camera editing workflow.

To enable multi-camera editing, follow these steps:

• In the Project panel, locate your multi-camera sequence.
• Drag this sequence into a new timeline to nest it.
• In the Program Monitor, click the Settings button (wrench icon) and select Multi-Camera instead of Composite Video. (You can also use the shortcut Shift + 0 to switch views.)

Once set up, you should see all camera angles in the Program Monitor, allowing you to switch between them easily.

[lvthunder]

OK so I did that and still get thousands of dropped frames.  So I thought my hard drive was too slow.  So I bought a new MVNE drive.  The fastest one I could get and copied the project and source files there.  When I opened the project and relinked all the media I noticed that the bar was red that shows if playback is going to be OK.  So I ran render in to out.  When it finished it played beautifully.  When it got to the end I hit play again and it was back to 1000s of dropped frames.  Do you have any other ideas?  Here is another screenshot.

[PaulMurphy]

Try dropping your playback resolution from Full to Half or Quarter. 

[lvthunder]

Dropping it to a quarter didn't make a difference.  I dropped it to 1/16 and it will play smoothly for about 15-20 seconds before it starts dropping frames.

In task manager nothing is even close to being pegged.

Should I make the proxys 1/4 size instead of the half and add a watermark so I can tell that they are actually being used?

[PaulMurphy]

Yep try that - there's a bottleneck somewhere. I would also suggest testing with proxies on your local drive.

[lvthunder]

I moved the whole project to a local internal fast drive.

I remade the proxies with the quarter watermark Prores Preset.

The same thing is happening.

I got a warning that said Clip Night 1 does not support low resolution proxy.  Creating medium resolution proxy.

Here is a screenshot that shows Task Manager while it was playing.  Can you think of something else I can try?  I really appreciate you helping me Paul.

[PaulMurphy]

Here’s a test to help determine where the bottleneck is occurring:

1. Duplicate your Premiere Pro project file.
2. Choose a problematic multi-camera sequence and make the media for this sequence offline.
3. Relink the offline media to the proxy files (use Link Media, not Attach Proxies).

Does the multicam sequence play smoothly now?

[lvthunder]

I did that and yes it plays smoothly.  The problem is they are very tiny.

[PaulMurphy]

This suggests that Premiere should be able to play those proxies without any issues.

I would recommend going back to your original project and doing 2 things:
1) Check the file path of your proxies in the Project panel - have you accidentally linked to the high-res media instead of the proxies? I notice in your second last screenshot that you have proxies enabled but some of the footage is not displaying a watermark.
2) Make your high-res media offline, so that only the proxies are attached.

[lvthunder]

I checked and the proxies are linked in the proxies folder.  So they are right.  I also made the high-res offline and the issue still exists.

[lvthunder]

I found out the clip that is giving me issues.  It is the clip that was shot with an iPhone.  I can play the two Canon R5, the GoPro, and the Insta 360 cameras and it works good.  Once I add in the iPhone angle is when it acts up.  The media properties of that file are below.  Any suggestions on what I should do?

Offline: User Requested
Media Path History:
M:\Figure Skating\Jerome iPhone\IMG_8742.M4V
/Volumes/T7//Figure Skating/Jerome iPhone/IMG_8742.m4v

Proxy Media

File Path: W:\Figure Skating\Jerome iPhone\Proxies\Night 1_Proxy.mov
Type: QuickTime Movie
File Size: 5.36 GB
Image Size: 1280 x 720
Frame Rate: 59.94
Source Audio Format: 44100 Hz - 16-bit - Stereo
Project Audio Format: 44100 Hz - 32 bit floating point - Stereo
Total Duration: 00:16:12:40
Pixel Aspect Ratio: 1.0
Alpha: None
Color Space: Rec. 709
Color Space Override: Off
Input LUT: None

QuickTime Details:
Movie contains 1 video track(s), 1 audio track(s), 0 closed caption track(s), and 1 timecode track(s).

Video:
There are 58360 frames with a duration of 1001/60000ths.

Video track 1:
Duration is 0:16:13:38
Average frame rate is 59.95 fps

Video track 1 contains 1 type(s) of video data:

Video data block #1:
Frame Size = 1280 x 720
Compressor = Apple ProRes 422 Proxy
Quality = Most (5.00)

Audio:
Audio track 1 contains 1 type(s) of audio data:

Audio data block #1:
Format = 16 bit - Stereo
Rate = 44100 Hz
Compressor = sowt

Timecode:
Timecode track 1 contains 1 type(s) of data:

Timecode data block #1:
Start Time = 00:00:00:00
Reel name =

[PaulMurphy · Accepted solution]

It looks like your original media has a variable frame rate (VFR), while your proxy is using a constant frame rate (CFR). This mismatch can cause playback and sync issues in multicam editing. To avoid these problems, I recommend converting your original media to CFR before creating proxies.

For more details on working with VFR media in Premiere Pro, check out this guide:

How to Work with Variable Frame Rate (VFR) Media in Premiere Pro

[lvthunder]

I converted the original clip to ProRes 422 and it resolved the issue.  Thank you so much Paul.  One more question though.  What would you recommend I transcode footage in the future to?  The original file is 8.28GB and the ProRes version is 276GB.

[PaulMurphy]

If you've got the time and the storage, I would recommend ProRes 422. 

[lvthunder]

What if I don't have the storage?  276GB for 4 minutes is a little extreme.

[PaulMurphy]

Look up the bitrate of the original video in something like MediaInfo, and create an h.264 version with a similar bitrate.