Replay window
The Replay window is the replay operator's desk for a Replay Channel. It shows the channel's picture and a timeline of the recording, from the first frame recorded to live. It has the transport and shuttle controls, a button for each angle, and what it takes to mark, name, tag, save and change a clip and to play it back from the project's clip bin.
The window works inside Composer, directly on the channel and the clip bin. Everything it does can also be done remotely, from a replay operator's browser page or a control surface, through the replay routes of the HTTP API.
Opening the window
Choose Windows ▸ Replay… from the application menu.
The window opens as a floating tool window that stays available while you work elsewhere in Composer. Press ESC to close it, and reopen it from the same menu entry. It closes when you enter performance mode. A project you open while it is open is picked up within a moment.
When the project has more than one Replay Channel, Replay Channel at the top chooses the one the window controls. The channel's playback status is shown beside it: live, playing at a speed, paused, at the start or end of a recording, or no output: after Stop, after a clip, or once the project is loaded, until the channel is first used, as its When loaded property says. Beside that is the recording session the channel plays, named after the time recording started, such as Recording 2026-10-12 143005. While a clip from an earlier session has taken the channel there, it reads Earlier recording …, until Live, highlighted.
The picture and the timeline
The picture is the channel's own, at the project's frame rate. The timecode in its corner is the time-of-day timecode of the frame on screen, and LIVE shows while the channel is live. While the channel shows no picture, as after Stop, the picture here is black.
Below the picture, the timeline runs from the first frame recorded, at the left, to the newest frame, at the right, with their timecodes at either end. While recording goes on, the right end moves with it. The handle is the frame on screen. Click or drag the timeline to go to a moment: the channel pauses there. The marked in and out show above the timeline, with the stretch between them.
While the channel plays a clip, or has one cued or paused, a green bracket under the timeline shows the clip's in and out, in the green of the clip bin's playing ring. It stays while you pause or change speed, and goes once the clip has played to its end or you step, jump, go to the start, go live or stop. It stays when you choose another angle, too. If that angle recorded only part of the clip, the bracket covers the part it recorded and runs to the edge of the timeline on a side it did not record, with no tick there. Marks you take while a clip plays show over the bracket, so a new in or out can be compared with the clip's own.
The channel plays the angle's recorded sound while it plays forward at normal speed, live or in a clip, and is silent paused, stepping, backwards or at any other speed. Its sound is in the audio mixer like any input's.
The channel's picture changes only while the channel is rendered. With Render Tuning on, a channel that is in no scene on air or in the preview is not rendered, and the window says so over the picture. Put the channel in a scene that is on air or in the preview, or turn Render Tuning off.
Moving through a recording
| Button | Key | What it does |
|---|---|---|
| Go to start | Home |
Pauses on the first frame recorded. |
| Step back 30 frames | Shift + Left |
Steps back 30 recorded frames and pauses. |
| Step back one frame | Left |
Steps back one recorded frame and pauses. |
| Play backwards | J |
Plays backwards at normal speed; press J again for twice normal speed. |
| Pause | K |
Pauses on the frame on screen. |
| Play | L |
Plays forwards at normal speed; press L again for twice normal speed. |
| Step forward one frame | Right |
Steps forward one recorded frame and pauses. |
| Step forward 30 frames | Shift + Right |
Steps forward 30 recorded frames and pauses. |
| Live | End |
Plays the newest frames, a few frames behind the frame being rendered. Highlighted while the channel is live. |
| Stop | Ends the clip playing and shows no picture, so the Replay Channel is transparent in its scene, until it is played, paused, stepped, cued or taken live. Playing, pausing or stepping goes on from the frame that was on screen when it stopped. A Speed set on the channel while it is stopped does not play it: Play then plays at that speed. |
Space plays a paused or stopped channel, as Play does, and pauses a playing one. Turn the mouse wheel over the picture to step through the recording a frame at a time, which is the jog; hold Shift to step 10 frames at a time. The Shuttle buttons play at twice, normal, half or quarter speed, backwards or forwards, and the speed the channel plays at is highlighted; while it shows no picture, the speed Play will play at. A Shuttle button plays at once, also while the channel shows no picture.
The keys work wherever the focus is in the window, except while you type in a text field.
Choosing the angle
The Angle row has a button for each Replay Recorder Target, and for any recorder that has recordings but is no longer in the project. Choosing one shows the same moment as that recorder recorded it. The angle shown is highlighted, and a red dot marks an angle whose recording is still being written.
Making a clip
- Move to the first frame of the moment and choose Mark in (
I). The in takes the timecode of the frame on screen. - Move to its last frame and choose Mark out (
O). The out cannot be before the in: on an earlier frame, Mark out is refused and the line at the bottom of the window says why. - Give the clip a Name, pick a Tag from the project's tag list or type a new one, and choose Save clip.
The angle the channel shows when you save a clip is the angle the clip plays from, and its thumbnail is the clip's first frame, the in, from that angle. To save a clip from another angle, choose that angle before you choose Save clip.
Marking needs a recording: until the channel has one, Mark in, Mark out, the in and out and Save clip are disabled. Marking an in after the out takes the new in and clears the out, so mark the out again. The in and out can also be typed as time-of-day timecodes, and the arrow beside each goes to it. Duration beside them shows how long the clip will be, from its in frame to its out frame with both counted. A clip left without a name is named after its tag and in, such as Goal 21:34:51:10. A tag typed that is not in the list yet is added to it. Once the clip is saved, the marks, the name and the tag are cleared for the next one. If the clip cannot be saved, the line at the bottom of the window says why.
A clip is a stretch of time, not a copy of the video, so it takes no disk space. It keeps the angle it was saved from and plays from there, but it can be shown from every angle. A clip can run past midnight, such as from 23:59:50:00 to 00:00:10:00, and is at most 12 hours long. The clip bin is saved with the project, so save the project to keep its clips.
A clip is saved in the recording session its in and out were marked in, so it plays from that session's recordings, also after a new recording has started or Composer has restarted. A clip whose in and out were typed rather than marked is saved in the session the channel plays.
The clip bin
The clip bin on the right lists the project's clips: thumbnail, name, tag, angle, in, out and duration. Angle is the angle the clip was saved from, which it plays from, under the name its Replay Recorder Target has now. Click a column's header to sort the clips by it, and click it again to reverse the order; Angle sorts by the names it shows. To make it wider, and the picture narrower, drag the gap between them. Show narrows the list to the clips with one tag. Clips saved elsewhere, such as from a browser page on the HTTP API, appear within a couple of seconds. The selected clip is highlighted, and selecting one loads it into the editor, as described in Changing a clip. The clip the channel is playing has the spinning green ring the input list shows for a running input; a clip that is cued or paused has none.
A clip's thumbnail is its first frame, from the angle the channel showed when the clip was saved. Mark in keeps a copy of the frame it marks, so a clip saved from that angle with that in has it as its thumbnail at once. Otherwise the thumbnail is made in the background a moment after the clip is saved, by reading its first frame from the recording again, on the processor at low priority rather than on the graphics card that renders. It is made again when the clip's in changes. The thumbnail box stays empty while it is being made. It shows a crossed-out picture when no thumbnail can be made, such as when the clip's recording has been deleted.
Thumbnails are kept on the computer that made them, in Composer's thumbnail cache rather than in the project file: %LOCALAPPDATA%\VindralComposer\ReplayThumbnails on Windows, with a folder per project and, inside it, one per Replay Channel. Deleting a clip does not delete its thumbnail. File ▸ Export ▸ Export project and all assets… copies the project's thumbnails with it, so they show where the project is opened from the export, even without the recordings. The HTTP API describes the cache's layout and serves the thumbnails to a browser page.
| Button | What it does |
|---|---|
| Play clip | Plays the selected clip from the angle it was saved from, from its in at normal speed, and pauses on its out; the Angle row then highlights that angle. Choose another angle while it plays to show the same moment from there. Double-clicking a clip, or pressing Enter on it, does the same. |
| Cue | Cues the selected clip on the angle it was saved from: paused on its in, ready to play. |
| Delete | Deletes the selected clip from the clip bin, after asking. No video is deleted. If the clip was in the editor, the editor is emptied for a new clip. |
The three buttons act on the selected clip, so they are greyed out until a clip is selected, and again after New clip clears the selection.
Right-click a clip to select it and open its menu: Play clip, Cue clip and Delete clip do what the buttons do.
To show a clip from another angle, play it and then choose the angle: the channel shows the same moment from there, and the clip plays on.
At clip end below the buttons chooses what the channel does when a clip has played to its end:
| Choice | What the channel does |
|---|---|
| Freeze frame | Pauses on the clip's last frame. |
| No output | Shows no picture until the channel is played, stepped, cued or taken live. |
| Next clip | Plays the clip after it in the clip bin, whatever its tag, at the same speed. After the last clip, it pauses on its last frame. |
| Return to live | Goes live. |
It is the Replay Channel's At clip end property, saved with the project, so it also applies to clips played from a browser page over the HTTP API.
Clips from an earlier recording
Playing a clip marked in an earlier recording session takes the channel to that session's recordings. Stepping, jumping, the timeline and the angle buttons then stay in that session, and the session readout at the top says so, until you choose Live, which returns the channel to the newest recording. Just after a project is opened, the earlier sessions its clips refer to are still being opened from disk; a clip played in that moment says so in the line at the bottom of the window; play it again a moment later.
Changing a clip
Select a clip in the clip bin to load it into the editor: the in, out, name and tag take its values, and Save clip becomes Update clip. Change any of them, or mark a new in or out, and choose Update clip to save the changes to that clip. Its duration is counted again, and it keeps its place in the clip bin. Selecting a clip only loads it; the channel goes on showing what it showed until you play or cue the clip.
Selecting another clip loads that one instead, and changes not yet updated are dropped. Choose New clip to empty the editor and the selection; Save clip then adds a new clip to the clip bin.
What the window needs
The window shows the reason at the top right when one of these is missing:
- A Replay Channel in the project. Add one to play the recordings back.
- The project is running. The channel's picture and playhead move on only while the project plays.