How Shotline works

How the timeline works

A few rules explain almost everything the timeline does when you drag, drop and trim.

Tracks are layers

Every row in the timeline is a track, and the timeline lists the highest track at the top. A clip on a higher track draws over clips on the tracks below it, so a title goes on a track above its video. To change the order without moving clips, right-click → Layer → Bring to Front, Bring Forward, Send Backward or Send to Back. Empty tracks close up on their own.

One clip at a time on a track

Clips on the same track never overlap (except for transitions, below). If you drop a clip where another one already is, the clips after it are pushed later to make room.

Transitions are overlaps

A transition is the part where the next clip starts before the previous one ends, on the same track. The length of the overlap is the length of the transition.

There are two ways to add one:

• Drag a clip so its start overlaps the end of the clip before it. A Fade is created, as long as the overlap.
• Select the later clip → Animation tab → Transition → pick one (Fade, Slide, Cross Zoom, Whip Pan, Blur Dissolve, Light Leak, Glitch, Cube and more). The clip moves so it starts that much before the previous one ends.

Change the length with the transition's Duration field, or drag the clip's left edge: on a clip with a transition, the left edge changes the transition, not the trim. Remove takes the overlap away too, so the clip moves to start where the previous one ends.

Splitting, snapping and selecting

• Split: put the playhead over the clip, right-click it → Split. The left part keeps the clip's enter animation and incoming transition, the right part its exit animation.
• Snapping: a dragged clip's start, end or centre snaps to other clips' start, end or centre when they're close; trimming edges snaps too.
• Several at once: drag a box on an empty part of the canvas or timeline, or ⇧ Shift-click / ⌘/Ctrl-click. Drag any of the selected items to move them all. In the Layers panel, ⌘/Ctrl-click adds a layer and ⇧ Shift-click selects a range.
• Track buttons (left of each track): mute (silent in the preview and the export), hide (not drawn) and lock (can't be moved or deleted).

Keyframes

A keyframe saves a property's value at a moment. Set one value at one time and another value later, and Shotline fills in every frame in between.

You can keyframe Position X and Y, Scale, Rotation, Opacity, and the Volume of video and audio clips. Keyframe times belong to the clip: move the clip and its animation moves with it.

Adding keyframes

1. Select the element and move the playhead to where the movement should start.
2. In the Properties panel, click the small diamond next to the property (for example next to X). It fills in: that's a keyframe at the playhead, at the current value.
3. Move the playhead later and change the value: type it, or drag the element on the canvas. Because the property already has a keyframe, the change becomes a new keyframe at the playhead. You don't click the diamond again.
4. Play it back. Add as many keyframes as you like.

Moving between keyframes and changing their feel

When an element has keyframes, a Keyframes box appears at the top of the Properties panel. Each animated property has arrows to jump to the previous or next keyframe, a menu for its easing (put the playhead on a keyframe first), and a bin to remove all of its keyframes. Keyframes also show as small dots on the clip in the timeline: click one to jump to it.

Animations

Ready-made motion for the start and end of a clip, between clips, and while it's on screen.

Select an element and open the Animation tab. It has four parts:

• Enter and Exit: how it arrives and leaves (Fade, Slide, Scale, Pop, Drop, Rise, Blur, Zoom Punch, Flip 3D, Reveal…). Texts get extra ones that animate letter by letter, like Typewriter, Scramble, Stomp, Shine and Neon.
• Transition: how it blends from the clip before it on the same track (see transitions are overlaps, with a recording).
• Loop: motion while it's on screen. Continuous loops (Ken Burns, Float, Breathe, Spin) run to the end of the clip; emphasis loops (Pulse, Heartbeat, Wiggle, Jello, Camera Shake) play for a moment and repeat. Starts at sets when it begins and Plays how many times (0 = until the end).

Every animation has a Duration, a Reversed option and an Easing. Curve-type easings show a curve you can drag to shape the motion yourself. Apply to all gives the same enter or exit animation to every other text (or clip) at that level, which is handy for a consistent title style.

Compositions (groups)

A composition is a small timeline inside your timeline: several clips that move, animate and fade as one.

1. Select two or more elements, right-click → Group. They become one clip on the timeline.
2. Double-click it (on the canvas, or its layer) to go inside: the timeline now shows only its contents.
3. Come back out with the breadcrumbs above the canvas, or Esc. Right-click → Ungroup puts the clips back.

Blend modes and track mattes

Two ways to combine a clip with what's below it: mix the colours (blend mode), or show the clip only through a shape (track matte).

Blend modes

In Properties, turn on Blend and pick a Mode. Each mode has a one-line hint in the menu. The ones you'll use most:

• Screen or Add for light leaks, fire, smoke and lens flares filmed on black: the black disappears and only the light stays.
• Multiply for paper textures, ink and shadows on white: the white disappears.
• Overlay and Soft Light for grain and colour washes that keep the picture underneath.

Track mattes

A matte shows a clip only through another layer. Put a text, shape or image above the clip, select the clip, turn on Track matte (it picks the layer just above) and choose a Mode:

Green screen

Remove a solid-colour background from a video or image (chroma key).

1. Select the clip, turn on Chroma Key and pick the backdrop colour (or a preset: Green, Dark green, Blue, Cyan, Magenta).
2. Raise Similarity until the backdrop is gone (default 0.4). Too high starts eating into the subject.
3. Smoothness softens the cut-out edge (hair, motion blur); Spill removes the green glow reflected onto the subject. Reset puts the defaults back.

Text boxes

Choose how a text box reacts when the text gets longer.

In Properties → Text, Sizing has four modes. Fixed size keeps both the box and the font size as you set them (long text can overflow).

• Use Auto width for short titles, Auto height for paragraphs, and Shrink to fit for templates where the text changes (names, prices) but must stay inside its space.
• Size is in vmin: a percentage of the frame's shorter side. Change the project from 16:9 to 9:16 and the text keeps its proportions.
• Upload Font in the font picker takes .ttf, .otf, .woff and .woff2 files (on plans that include custom fonts). Picking a different font by name afterwards stops using the uploaded file.
• Text is edited in the Properties panel; double-clicking text on the canvas doesn't edit it.

Video, audio and image settings

The settings that change what plays, and how long the clip is.

Captions

Word-by-word animated captions from your video's speech, in two places: the Captions page for a quick captioned video, and the editor for captions inside a bigger edit.

On the Captions page

1. Upload a video and choose Captions when asked what it's for (or, in Media, open a video's menu → Add captions). Transcription starts right away; the language is detected automatically.
2. Pick a look from the style gallery: it previews on your own words. Fix any misheard words in Transcript: click a line, type, press Enter (Esc cancels; the timestamp button jumps the video there).
3. Fine-tune the style (below), then Render Video. When it's done, Download Video. It also appears under Projects → Captions.

In the editor

Select a video or audio clip and click Generate Captions in its Properties. You get a Captions clip on the track above (or on a new top track if that space is taken), starting with the clip and timed to its words, already adjusted for the clip's trim and speed. It's an ordinary clip: move it, trim it, style it.

Styling options worth knowing

• Mode: Highlight words (all words shown, the spoken one highlighted), One word at a time, Karaoke sweep or Plain text.
• Highlight style: Colour, Pill (a box behind the spoken word), Bigger, Glow, Underline. Spoken and Upcoming set how already-said and not-yet-said words look.
• Words per line and Lines set how much shows at once. New page at pauses starts a fresh page when the speaker pauses, so a sentence doesn't straddle two thoughts.
• Position → Lower keeps captions clear of the TikTok, Reels and Shorts buttons.
• Highlight early lights each word up to 300 ms before it's spoken, which often feels more in sync.

AI Reframe

Turn a wide video into vertical, square or any other shape. The AI follows the people in it and keeps them in frame.

1. Upload a video and choose Reframe when asked what it's for (or, in Media, open a video's menu → Reframe).
2. Choose the shape: 9:16 (Reels, Shorts, TikTok), 1:1, 4:5, 2:3 or 16:9.
3. Choose Framing: Keep it sharp never enlarges the video much; Balanced zooms in moderately on small subjects; Tighter framing zooms in more, even if the picture gets softer.
4. Click Reframe. It analyses the video (usually about a minute) and shows a preview. Then Render to MP4 and Download MP4.

Shot by shot, it picks a layout: following the subject, the whole picture, a split screen for two people, or the person over a blurred background when nothing else fits.

Saving and versions

Everything saves automatically. You only see a message when something needs your attention.

• No message means saved. A banner appears only if saving is retrying, you're offline, you've been signed out, or the project changed somewhere else.
• Offline? Keep working. Your changes are kept on this device and save when you're back online.
• Unsaved changes found: if the browser closed before a save finished, reopening the project offers to Restore them (they were kept on that device) or Discard them.
• Changed elsewhere: if the project was saved from another tab or device, choose Reload (take theirs) or Overwrite (keep yours). Only one tab edits a project at a time; another tab asks before taking over.

Version history

The clock button in the editor's toolbar opens Version history. A version is saved every few minutes while you edit, every time you render, and when you leave with Save & Leave; the latest 50 are kept. Pick one to see what changed, then Restore. What was open is saved too (as Before restore), so you can always switch back.

Exporting and sharing

Render turns the project into an MP4 in the cloud; you don't need to keep the tab open.

• Render (top right) saves your latest changes first, then renders exactly that version. You can close the progress window, or the tab: the render carries on. Cancel render returns its minutes to your plan.
• Renders lists every render of the project with a preview and Download.
• Render minutes count the length of the video you render (not the time it takes). They reset each month and are refunded for failed or cancelled renders. Your plan also sets the highest resolution: a bigger project is scaled down to it. See Settings → Plan & usage for your numbers.

Templates and the API

Any project can be a template: render it from your own code or Zapier with different text and media each time.

1. In the project, give the layers you want to change clear names in the Layers panel (the pencil button), for example Title or Logo.
2. Click Use Template. It lists what you can change (named text and caption layers take text; named video, image and audio layers take a public file URL) and gives a ready-to-copy snippet in cURL, Node.js or Python.
3. Create a key in Settings → API keys. You see it once, so copy it then.

curl -X POST https://api.shotline.in/api/v1/render \
  -H "Content-Type: application/json" \
  -H "X-API-Key: YOUR_API_KEY" \
  -d '{
    "templateId": "YOUR_TEMPLATE_ID",
    "variables": {
      "Title": "Summer sale: 30% off",
      "Logo": "https://example.com/logo.png"
    }
  }'

# 202 { "id": "…", "status": "pending", … }
# Then GET /render/{id} until status is completed, failed or cancelled:
# completed → outputUrl (watch) and downloadUrl (file)

• Variables match layer names; layers with the same name change together. A name that matches nothing comes back in warnings instead of failing the render.
• Renders use the project's last saved version, so the Use Template window saves your changes when it opens.
• Add webhookUrl to be called when the render finishes instead of polling, and an idempotencyKey so a retried request never starts a second render.

Keyboard shortcuts

⌘ on a Mac, Ctrl on Windows and Linux. Shortcuts don't fire while you're typing in a field (except undo and redo).