# VSE: How do I speed up playback in the video preview?

I am trying to scrub through a large video (2+ hours) so that I can cut out a few clips from it. The video preview window is too slow when I click to a new time location in the sequence view.. it can take several seconds to show the preview. I've rebuilt the proxy and timecode indices but this doesn't seem to help.

I'd be happy if I could speed up the playback of the preview. Note that I DO NOT want to speed up the resulting video, I just want to scrub through the video to find the right places to cut.

I've tried the following approaches:

• Increased the memory cache limit to 4096. The preview is still just as slow.
• Rebuild proxy and timecode indices using "Record Run" and a proxy size of 25%. This did not help.
• Speeding up the video using "Time Remapping" in the properties window. This speeds up the video preview, allowing me to scrub through the video but when I turn the time remapping back to 1:1, the position in the video changes so I lose the place I wanted to cut.
• Applying a speed control effect strip. This has the same problem as using time remapping.

The source video is H.264. I have heard that re-encoding can help speed up the preview, but I don't want to suffer the loss of quality that re-encoding will introduce.

Is there any way just to set the playback speed to 2x, 4x or something for the purposes of preview only?

• What proxy size did you use? Maybe try the lowest possible Jan 30, 2019 at 15:12
• Yeah I used 25%.
– Erik
Jan 30, 2019 at 15:13

Just hit this myself after not using the feature for a while. Did you change the Preview to use the proxy? It's Proxy Render Size under the View tab in the properties (N) pane.