#Output time and source time

CutZal never changes the original recording. It keeps a list of the parts to keep, and the edited video plays those parts back to back.

• Source time is a moment in the original recording (the master recording when the project has several sources). It does not change when you cut.
• Output time is a moment in the edited video. Cutting earlier speech moves later output times earlier.

All times are seconds with up to 3 decimals.

#Where each time is used

#Converting

context.output.segments lists the kept parts in output order: { masterStartS, masterEndS, outputStartS }. A part played faster or slower (a speed edit) also has rate, and mute: true when its sound is off. rate is 1 when it is missing. A segment covers output time outputStartS to outputStartS + (masterEndS - masterStartS) / rate.

• Output to source: find the segment that contains output time t, then source = masterStartS + (t - outputStartS) * rate.
• Source to output: find the segment whose masterStartS <= s < masterEndS, then output = outputStartS + (s - masterStartS) / rate. If no segment contains s, that moment is cut.

Usually you do not need to convert: transcript already gives both times for every word.

#Choosing the coordinate

• To cut what the viewer currently sees and hears, use output time from the current transcript. Read it again after each apply, because output times move.
• To refer to the recording itself (for example "the second take of the intro"), or to restore something that was cut, use source time. Source times stay valid across edits.
• Clips pinned with output anchors stay at their output time when speech is cut or restored. Check with capture after large cuts.

#Frame fields

Layout edits (placement with camera or screen) and the frame of screen and camera clips use these fields. Positions and sizes are fractions of the output picture, so they do not depend on its resolution.

• pos: a 9-grid name (tl, tc, tr, ml, mc, mr, bl, bc, br for top, middle, bottom and left, center, right; with a small margin from the edge) or { "x", "y" } from 0 to 1 for the frame's top left corner.
• sizePct: width as a fraction of the output width, above 0 and at most 2. The camera default is 0.24.
• radiusPx: corner rounding in pixels, 0 to 4096.
• padPx: space inside the frame around the picture in pixels, 0 to 4096.
• aspect: 1:1, 4:3, 3:4, 16:9, or media (the recording's own shape).
• mirror: true flips left and right.
• focus (optional): { "x", "y" } from 0 to 1, the point of the recording to keep at the center of the frame when the frame crops it (for example a 3:4 camera frame over a 16:9 recording shows only the middle 42% of its width). It is measured on the recording itself, top left, before mirror, so turning mirror on or off keeps the same part in view. Without it the frame shows the middle (0.5, 0.5); sending { "x": 0.5, "y": 0.5 } removes it. Values that would show past the edge of the recording stop at the edge, and an axis the frame does not crop (the height in that 3:4 example) ignores its value. To center a face that sits left of the middle, give the face's position, such as { "x": 0.42, "y": 0.5 }; check with capture. A project with a focus is saved as file version 20, so older CutZal versions refuse to open it instead of showing the middle.