Getting smooth playback in Video by Zaweba

An editor that stutters is hard to judge timing in. Cuts feel wrong when they are fine, and music edits are impossible to hear properly. Video by Zaweba has a small set of playback controls that get most computers playing smoothly, and a way of seeing what your machine can manage.

Preview quality

The Playback menu sets preview quality to Full, Half or Quarter. Full draws the preview at the project's size. Half and Quarter draw it smaller, which takes far less work. On a laptop or an older desktop, dropping to Half often turns a juddering timeline into a smooth one.

This only affects what you see while you edit. Exports are always made at the proper size, so lowering preview quality costs nothing in the finished file. Switch back to Full when you need to check focus or fine detail.

Decoding with the graphics card

Modern graphics cards have hardware for decoding common video formats. Video by Zaweba can optionally use it. Turning it on moves the work of reading compressed footage off the main processor, which often helps a great deal with high resolution camera files.

It is an option rather than the default because results depend on the card and its drivers. If playback improves, keep it. If you see glitches, turn it off and use the other settings instead.

The dropped-frame counter

Without a counter, you are guessing whether playback is keeping up. The dropped-frame counter shows how many frames the preview skipped. If it climbs while you play, the machine is not keeping up, and it is time to lower the preview quality or render the busy stretch.

It is also a quick way to test a change. Play the same section before and after turning on graphics card decoding, and the counter tells you whether it helped.

System report and speed test

Help > System report and speed test checks your machine and reports what it found. That is useful when deciding on settings, and when asking someone for help: a report gives facts about the hardware instead of guesses.

Run it when you first install the app on a new computer, so you know where you stand. Run it again after a driver update or a hardware change, and compare. If something got slower, the report gives you a starting point for finding out why, rather than a vague feeling that the app is not as quick as it was.

A plan for a slow timeline

Work through the options in order. First drop the preview to Half, then Quarter if needed. Next try graphics card decoding. If a particular stretch is still heavy because of effects, render previews for it, and for a finished clip that keeps dragging, use render and replace. Watch the dropped-frame counter at each step.

Proxies, lighter copies of heavy footage, are another option for very large camera files. Closing other heavy programs and keeping scratch disks on a fast drive with free space help too.

With those settings, Video by Zaweba runs comfortably on a wide range of hardware. The aim is not the sharpest possible preview, but a preview smooth enough to make good editing decisions.