Sequencer lag with ImgMedia textures

I’m getting some odd freezing in Sequencer, while using ImgMedia textures. I have 3 in my scene, and they’re set to loop. They’re 2048x1024 PNG files. One of them is 120 frames (which plays with zero lag if that’s the only one I have), and 2 others that are both 9 frames each. If I don’t stretch the Sequencer media tracks for the two 9-frame ImgMedia players, it will play just fine, no probs.
But once I stretch them to take up the full 1000-frames, sequencer will randomly hang for 4-5 seconds while playing, then jump way forward. I can scrub the Sequencer timeline in the editor, and there’s zero lag or pauses, and I can export the movie from Sequencer, with zero lag or pauses. But this freezing makes it darn near impossible to actually get work done in-editor.

I don’t see any errors in Output Log, but I do see what I assume are ImgMedia frame load warnings? I have no idea what these mean, but there are a lot of them when I play or scrub the timeline.
When I was using Mp4 video for the media players, I didn’t have this issue. I switched to image-based sequences, since Mp4’s were not properly syncing to the frame output of sequencer.

Any ideas would be greatly appreciated.

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I have the exact same issue and had to switch to image-based sequences for the same reason. I had no issue playing 4 videos in a scene before, and now as soon as I go over 2 image-based sequences exporting a simple video from a level sequence takes forever. Any idea why there is a sudden performance drop?


Same here! I working on streaming live from with in the engine and render out on the movie render queue so I really want to find a workaround. Have tried a lot of different things without it working…

I’m having the same issue. I have two media textures - one as a screen texture which is 960x540 and the other one i’m using for light, that one is 149x84. When I mute one it works great but when there are two at the same time, the timeline lags really bad. But scrubbing through the timeline seems to work just fine, it doesnt lag at all. Just while playing.

Having this issue as well - any solves for this?

I’ve found a solution that works for me on UE 4.27. Go to project settings and under the img media plugin cache settings increase the ‘cache behind percentage’ to 100, ‘Cache Size GB’ to 200, and ‘cache threads’ to 64. I hope this helps someone.