# Editing & Mastering

The CoreReflex Studio is where your work comes together — film, audio, music, image, and design alike. You cut on a multi-track timeline with a full snapping suite and pro trim tools, animate any property with keyframes and hand-shaped curves, key out green screens, ramp speeds, caption and translate the spoken word, edit video by editing its transcript, master the audio, and render a finished file with one click — all in the browser at [editor.corereflex.com](https://editor.corereflex.com).

This guide is the editor manual. Each section is a job you'd actually do, in roughly the order you'd do it. For how a project flows from brief to master, see [Directing Films](directing-films.md) and your studio dashboard.

> **The look stays true from preview to render.** What you see in the player is what comes out of the render. Color grades, transitions, green-screen keys, and keyframe animation use the same composition in the live preview and in the render service, and audio FX are baked in by a real audio-processing pass on the same timeline — so there are no surprises at the end.

**On this page**

- [The timeline studio](#the-timeline-studio)
  - [Cut at the playhead (razor)](#cut-at-the-playhead-razor)
  - [Snapping — land every edit exactly](#snapping--land-every-edit-exactly)
  - [Markers & chapters](#markers--chapters)
  - [Deleting clips & closing gaps](#deleting-clips--closing-gaps)
  - [Pro trims: ripple, roll, slip & slide](#pro-trims-ripple-roll-slip--slide)
  - [Trim to the playhead (top & tail)](#trim-to-the-playhead-top--tail)
  - [Separate (and re-attach) audio](#separate-and-re-attach-audio)
  - [Tighten the delivery: remove filler words and silences](#tighten-the-delivery-remove-filler-words-and-silences)
  - [The timeline grid — timecode or musical bars](#the-timeline-grid--timecode-or-musical-bars)
  - [Undo that keeps up with you](#undo-that-keeps-up-with-you)
- [Knowing what the studio is doing](#knowing-what-the-studio-is-doing)
- [Video tools](#video-tools)
- [Animate anything with keyframes](#animate-anything-with-keyframes)
- [Project-wide color grade](#project-wide-color-grade--one-consistent-look)
- [Seamless transitions](#seamless-transitions)
- [Audio FX & mastering](#audio-fx--mastering)
- [Captions, subtitles & the transcript](#captions-subtitles--the-transcript)
- [Rendering your master](#rendering-your-master)
- [Version history & comments](#version-history--comments)
- [Shorts Studio](#shorts-studio)
- [A few neighbors worth knowing](#a-few-neighbors-worth-knowing)
- [Keyboard shortcut reference](#keyboard-shortcut-reference)
- [Troubleshooting](#troubleshooting)

---

## The timeline studio

The timeline is the source of truth for your edit. It's a multi-track surface: stack video, images, text, captions, and audio on separate tracks, drag clips to reposition them, and trim their edges.

A few things worth knowing as you work:

- **The playhead is the cyan line.** That bright cyan marker is your current position in time — the "now" of the edit. Everything you do (splitting, captioning, cleaning audio) happens relative to where the playhead sits.
- **Two tools, two keys.** The **select** tool (press `V`, or `Esc`) is the default — drag, trim, and arrange. The **blade** tool (press `B` or `C`, or click the scissors in the toolbar) cuts clips where you click, just like Premiere's razor or CapCut's blade.
- **Tracks can be hidden or muted.** Toggle a track's visibility or mute it to audition the mix or focus on one layer without deleting anything.
- **Zoom in for precision.** Use the zoom slider to spread the timeline out when you need frame-accurate cuts, then zoom back out to see the whole piece. Filmstrip thumbnails and audio waveforms render right on the clips so you can cut on a visual or a beat.
- **Undo is always there.** Every edit commits to the undo stack — `Cmd/Ctrl+Z` to undo, redo to step forward. Save with `Cmd/Ctrl+S` (your work also persists automatically as you go).

### Cut at the playhead (razor)

To split a clip into two pieces at the current position:

1. Select the clip on the timeline.
2. Move the playhead to where you want the cut.
3. Click the **scissors** button (Split Clip at Playhead).

The clip splits cleanly into two independent pieces at the playhead. The button is only active when the playhead is actually *inside* a selected clip, so you can't accidentally cut on empty space. Select several clips first and one click splits all of them at the same frame.

### Snapping — land every edit exactly

As you drag or trim, clip edges lock onto the things you'd want them to line up with — no pixel-hunting:

- **Other clips' edges.** The start and end of every other clip on the timeline.
- **Grid lines.** When the [timeline grid](#the-timeline-grid--timecode-or-musical-bars) is on — beats in BPM mode, timecode divisions in SMPTE mode.
- **Markers and chapters.** Every flag you've dropped on the ruler is a snap target too.

All three feed one ranked snap engine, and when a snap lands, a **labeled indicator line** appears down the timeline telling you *what* you snapped to — **Clip**, **Grid**, or **Marker** — each in its own color, so you always know why the clip just clicked into place.

Controlling it:

- **Toggle snapping** with `Shift+M`, or with the snapping toggle in the timeline toolbar. Your preference is remembered.
- **Bypass it for one move:** hold `Cmd` (macOS) or `Ctrl` (Windows) *while dragging or trimming* to temporarily ignore all snap targets — perfect for a deliberate one-frame offset next to a snap point.
- **Nudge to the grid from the keyboard:** with clips selected, press `]` to jump the selection to the **next** grid line and `[` to the **previous** one. Multi-selections move as a block, so relative spacing between the selected clips is preserved. (Needs the grid switched on.)

### Markers & chapters

Markers are flags on the timeline ruler — drop them on beats, notes-to-self, or chapter starts, and navigate the piece by them.

**Dropping and using markers:**

1. Park the playhead where you want the flag.
2. Press `M`. A marker appears on the ruler at that frame.
3. Press `Option/Alt+→` to jump the playhead to the next marker, `Option/Alt+←` for the previous one — the fastest way to hop between the beats of a long edit.
4. Click any flag on the ruler to seek straight to it; hover a flag to see its label.

**The Markers panel:** open the **Project** panel (click empty timeline space to deselect, or use the Project tab while a clip is selected) and find **Markers**. From there you can:

- **+ Add** a marker at the playhead.
- **Rename** any marker inline (press Enter or click away to commit).
- **Click the colored diamond** to cycle its type: **marker → chapter → to-do** — each type wears its own color on the ruler, so chapters and open to-dos read at a glance.
- **Click the timecode** to jump the playhead there.
- **Delete** a marker with the × that appears on hover.

Markers are part of the project, ride the undo stack, and — as noted above — act as snap targets when you drag clips.

### Deleting clips & closing gaps

Two flavors of delete, plus gap cleanup after the fact:

- **Lift delete — `Delete` / `Backspace`.** Removes the selected clips and *leaves the hole*, like lifting a clip out of a Premiere sequence.
- **Ripple delete — `Shift+Delete` / `Shift+Backspace`.** Removes the selected clips *and closes the gap*, pulling everything downstream left so the timeline stays tight where the deletion happened.
- **Close a gap later.** Right-click any clip and choose **Close gap after** (collapses just the empty space following that clip) or **Close all gaps on track** (makes the whole track contiguous from its first clip). These entries only appear when there's actually a gap to close — and they're smart about transitions: the intentional overlap a transition creates is never mistaken for a gap.

### Pro trims: ripple, roll, slip & slide

The full NLE trim vocabulary is here, driven by modifier keys — the same muscle memory as Premiere and Resolve:

| Trim | How | What it does |
|---|---|---|
| **Trim** | Drag a clip's edge | Changes the in- or out-point. Clamped by neighbors and by how much source material the clip actually has. |
| **Ripple trim** | Hold `Option/Alt` and drag a clip's edge | Trims the edge **and shifts everything downstream** on the track by the same amount — the edit never opens or swallows a gap. The trimmed clip stays glued in place; the material before the edit never moves. |
| **Roll** | Drag the thin handle at the seam between two touching clips | Moves the shared edit point: one clip gets longer, its neighbor gets shorter, and the overall timing of everything else is untouched. |
| **Slip** | Hold `Option/Alt` and drag a clip's **body** | Changes *which part of the source* the clip shows without moving the clip on the timeline. Drag right to reveal earlier material, left for later. The clip's position and length never change. |
| **Slide** | Hold `Option/Alt+Shift` and drag a clip's **body** | Moves the clip along the track while its two touching neighbors absorb the move — the previous clip's out-point and the next clip's in-point follow, so the three-clip block keeps its outer boundaries and total length. |

Every trim respects the source: a media clip can never reveal frames its file doesn't have, and a neighbor across a gap clamps a slide (you can travel the gap, never overlap). Fades on the trimmed clips are re-clamped automatically so they never exceed the new clip length.

One nuance: during a **ripple trim**, snapping is intentionally off — the usual snap targets (the neighbors' edges) are exactly the clips the ripple is about to move.

### Trim to the playhead (top & tail)

The fastest way to top-and-tail a clip:

1. Select one or more clips.
2. Park the playhead where the clip should start or end.
3. Press `Q` to set the selected clips' **in-point** to the playhead, or `W` to set their **out-point**.

These are real trims — all the usual clamps apply (neighbor collision, source headroom, one-frame minimum) — so pressing `Q` before a clip's start *extends* it to the playhead exactly like dragging the handle would.

### Separate (and re-attach) audio

Like a pro NLE, you can detach a video clip's sound onto its own track so picture and sound can be edited independently — then re-group them when you're done.

- **Right-click a video clip → "Separate audio."** The clip's audio moves to its own track as a linked audio item, and the video is silenced (reversibly). The picture and the sound now move and trim independently — slip the dialogue, J-cut the next scene, or extend a line of narration under a different shot.
- **Right-click either half → "Re-attach audio"** to re-group them. The video's original volume is restored and the detached audio item (and its now-empty track) is removed.

"Separate audio" only appears on a video clip that actually has an audio track and hasn't already been detached, so the menu only offers it when it makes sense. Behind the scenes the detached audio points at the *same* source file — there's no second upload, and your locally cached media keeps working.

### Tighten the delivery: remove filler words and silences

Open a talking-head or narration clip and use the **Clean up audio** panel to cut "um," "uh," and dead air automatically — Descript/CapCut style.

1. Click **Analyze audio.** CoreReflex transcribes the clip with word-level timing.
2. Choose what to cut with the toggles:
   - **Filler words** — removes a conservative set of non-words (*um, uh, erm, hmm, mhm, huh…*) that are almost never meaningful speech.
   - **Long pauses** — trims gaps in speech. Pick the threshold: trim pauses longer than **0.6s, 0.9s, 1.5s, or 3s** (0.9s by default).
   - **Aggressive** — also removes real words used as crutches (*like, you know, basically, literally, actually, so, well…*). This one is riskier, so it's off by default.
3. The panel shows you exactly what it will do before you commit — e.g. *"Removing 4.2s · 7 fillers · 3 pauses."*
4. Click **Clean up clip.** The clip **ripples closed automatically** — the pieces rejoin with no gaps, so your timeline stays tight.

A small breathing pad (~120ms) is kept around speech so cuts don't sound clipped, and the whole thing is undoable. Very long clips can't be cleaned automatically (there's a duration limit) — split them first, or clean section by section.

There's an even nicer way to do this once captions exist: the [transcript panel](#the-transcript-panel--edit-video-by-editing-text), where fillers and pauses are highlighted right in the text.

### The timeline grid — timecode or musical bars

Read and cut your timeline two ways. The grid controls in the timeline's action row let you switch the ruler, the time readout, and snapping between:

- **Timecode (SMPTE).** The broadcast clock — `HH:MM:SS:FF`. Pick the frame rate the piece is mastered at: **23.976, 24, 25 (PAL), 29.97 (NTSC drop-frame), 30, 48, 50, 59.94 (drop-frame), or 60 fps**. The 29.97 and 59.94 options use proper drop-frame counting so the displayed time stays honest over long durations. The frame rate is **runtime-switchable** — change it and every clip's timing is rescaled so a one-second clip stays a one-second clip, and the ruler, the readout, and the render all follow.
- **Musical (BPM).** Bars, beats, and ticks instead of seconds — set the **tempo, time signature, and subdivision**, and the ruler lays down bar and beat lines so you can cut music exactly on the downbeat.

Turn on **Snap to grid** and grid lines join the snap targets described above — on the beat in BPM mode, on the frame division in timecode mode. Leave it off and the grid is purely a visual reference. The `[` / `]` gridline nudge works whenever the grid is on.

### Undo that keeps up with you

Undo is designed around *intentions*, not keystrokes:

- **A drag is one undo step.** Trim a clip, drag a keyframe, shape a curve — however long the gesture, releasing the mouse commits exactly one entry (and a drag that ends back where it started commits nothing).
- **Typing a value is one undo step.** Typing "0.35" into a precise numeric field coalesces into a single entry instead of three.
- **An AI edit is one undo step.** When the studio's AI assistant applies a multi-step edit to your timeline, the entire run lands as one entry — one `Cmd/Ctrl+Z` restores the document exactly as it was before you asked.

---

## Knowing what the studio is doing

The studio tells you what it's working on, so you're never staring at a frozen panel wondering whether a generation actually started.

- **A thin progress line across the top.** Kick off anything that takes a beat — generate a voiceover, score a track, produce shots, save, render, process audio FX — and a slim accent bar appears at the very top of the studio. It shows real progress when the task reports it (per-shot during a film, percent during a render) and a gentle sweep otherwise, then finishes and clears on its own.
- **Toasts.** Each action pops a brief notification — *success* when it lands, a clear *error* with the reason when it doesn't — so a failure surfaces instead of disappearing.
- **The activity log.** Click the **≡ Activity** button in the studio bar to open a running log of what's happened this session — every generation, save, caption, and export, with its outcome. It's the place to check "did that finish?" after you stepped away.

Buttons also give a little tactile feedback — a subtle press on click, and a faint lift on the primary actions — so the studio feels responsive under your hand.

---

## Video tools

Select a video clip and open its inspector — these four tools live there.

### Green screen (chroma key)

Key out a green screen — or any flat backdrop color — so the clip becomes transparent where the color matches, revealing whatever sits on the tracks beneath it.

1. Select the video clip and click **Enable green screen key**.
2. Use the **Key color** swatch to pick the exact backdrop color (green is the default).
3. Dial the three sliders while watching the live preview:
   - **Similarity** — how wide a net the key casts around the chosen color. Raise it if patches of backdrop survive; lower it if parts of your subject start disappearing.
   - **Softness** — feathers the edge of the key so hair and edges blend instead of cutting hard.
   - **Spill removal** — desaturates the green tint that bounces onto your subject's edges.

The key you see in the preview is exactly the key that renders — same engine both places. Click **Disable** to remove the key entirely. Slider drags preview live and land as one undo step on release.

### Speed & speed ramps

The **Speed** slider on a video clip changes its playback rate. For the cinematic version — speed that *changes over the clip* — use the **Speed ramp** preset chips:

| Preset | What it does |
|---|---|
| **Ramp in** | Starts fast (2.5×), settles to normal speed. |
| **Ramp out** | Normal speed, then accelerates out (2.5×). |
| **Slow-mo hit** | Dips into 0.4× slow motion for the middle beat. |
| **Rush** | Blasts through the middle at 3×. |

One click splits the clip into contiguous pieces at the preset's rates — one undo entry, and later clips on the track ripple automatically to absorb the length change. The pieces are ordinary clips afterwards: trim, retime, or delete each one freely to fine-tune the ramp.

### Extend with AI

Ran out of footage a beat too early? **Extend with AI** generates a seamless continuation of the clip from its own last frame and inserts it right after on the track.

1. Select the clip and find **Extend with AI** in the inspector.
2. Optionally describe what happens next in the prompt field (leave it empty for a natural continuation).
3. Click **⏵ Extend clip** and watch the stages tick by — reading the last frame, generating, placing the clip.

The generated continuation lands as a normal clip immediately after the source, ready to trim or grade like anything else.

### Auto-reframe to canvas

Converting 16:9 footage to a 9:16 vertical (or a square) usually means hand-nudging every clip so the subject isn't cropped out. **Auto-reframe** does it in one click:

1. Set your project to the target canvas (e.g. vertical).
2. Select a clip and click **◫ Auto-reframe to canvas**.

The AI finds the main subject in the clip and sizes + positions the clip so it fills the composition with that subject centered. If no clear subject is found, it centers the frame instead (and tells you so). One undo entry reverses it. The clip needs to be uploaded (cloud) media — freshly recorded local-only footage should finish uploading first.

---

## Animate anything with keyframes

Every numeric property on a clip can be animated over time — position, size, opacity, rotation — with the same stopwatch-and-diamond workflow you know from After Effects, and the same result in preview and render.

### Setting keyframes

1. Select a clip and find the property in its inspector — **Position**, **Dimensions**, **Opacity**, or **Rotation** each carry a small **stopwatch** next to them.
2. Click the stopwatch to start animating. A first keyframe is planted at the playhead holding the current value.
3. Move the playhead, then change the value — a new keyframe is written at that frame automatically. Repeat to build the motion.
4. The **diamond** next to the stopwatch adds or removes a key exactly at the playhead: filled means a key sits on this frame, hollow means the playhead is between keys.

Position animates X and Y **together** as one compound property, and Dimensions animates width and height together — so a move is always one coherent path, never a mismatched pair of tracks. While a property is animated, its slider live-tracks the value at the playhead. Turning the stopwatch off removes the keys and bakes the current value back in.

### The keyframe lane

Every clip with keyframes grows a slim **lane along its bottom edge** on the timeline — one diamond per frame that carries a key on any animated property.

- **Drag a diamond** left or right to retime that beat of the animation — the whole column of keys at that frame moves together. While snapping is on, a dragged diamond snaps to the playhead for frame-exact timing.
- **Right-click a diamond** to apply an **easing preset** to the keys at that frame.

### Easing — presets and the Curve tab

Every keyframe carries the easing for the segment it starts. The named presets — **Linear, Smooth, Ease In, Ease Out, Snappy, Overshoot, Anticipate, Bounce, Hold** — are available both on the lane's right-click menu and in the Curve tab. (New keyframes default to a smooth ease-in-out.)

When a preset isn't enough, shape the curve by hand. With a keyframed clip selected, the inspector shows a **Clip | Curve | Project** tab strip — open **Curve**:

1. Pick the **property** (X, Y, W, H, Opacity, Rotate) along the top.
2. Pick the **segment** — each button is one keyframe-to-keyframe span, labeled by its frames.
3. **Drag the two handles** on the bezier graph to shape the acceleration. Handles can travel above and below the square, so overshoot and anticipation are fully expressible.
4. For surgical precision, type the four handle values (P1 x/y, P2 x/y) into the numeric fields — rapid edits coalesce into one undo step.
5. **Apply this curve to all properties on frame N** copies the segment's easing across every animated property at that frame, so a compound move eases as one.

Presets like Bounce and Hold aren't single curves, so they have no draggable handles — the graph still previews their exact shape, and picking any bezier preset returns you to hand-editable territory.

### Convert a fade to keyframes

A clip's simple fade in/out is quick, but sometimes you want to *own* the curve. Right-click a faded clip and choose **Convert fade to keyframes** — the fade becomes real opacity keyframes you can retime, reshape in the Curve tab, or extend into something more elaborate. (The option appears only when the clip has a fade and its opacity isn't already keyframed.)

### Or just ask the AI

The studio's AI assistant speaks fluent keyframe. Open the assistant panel and ask in plain language — *"fade the logo in over the first second, then drift it up slowly"* or *"make this clip pop in with an overshoot"* — and it plans and applies the keyframes and easings for you, on the same engine your manual edits use. The whole run lands as **one undo entry**, so if you don't like it, one `Cmd/Ctrl+Z` puts everything back.

---

## Project-wide color grade — one consistent look

Give the entire film a single, cohesive look instead of grading clip by clip. The **Project Color** grade applies once at the root of the composition, so every shot inherits the same treatment — exactly like a master grade.

In the **Project Color** panel:

- **Pick a Look.** Curated, cinema-leaning presets: *Teal & Orange, Bleach Bypass, Noir, Golden Hour, Cold Steel, Vivid, Warm Film, Vintage* (or **None**).
- **Fine-tune with sliders:** Brightness, Contrast, Saturation, **Warmth** (cool ↔ warm), Shadows, and Highlights. Adjusting any slider switches you off the preset and into your own custom look.
- **Match look to all clips.** Select exactly one clip you've already graded and click this to copy its grade across the whole timeline — a fast way to lock a look you nailed on one shot. (The button is only active when exactly one clip is selected.)

Per-clip grading still exists for fine control (in a clip's own Color panel), and a per-clip grade **composes on top** of the project grade. So you can set one master look for the film and still nudge a single shot that needs it. The preview and the export use the same grading engine, so they match exactly.

---

## Seamless transitions

Add a transition between two clips that sit next to each other **on the same track**. Select the outgoing (earlier) clip and open its **Transition** panel.

| Transition | What it does |
|---|---|
| **Dissolve** | The next clip fades up over the current one — a clean cross-dissolve with no mid-dip. |
| **Dip to Black** | Fades down to black and back up — a classic scene break. |
| **Wipe Left / Right / Up** | The incoming clip slides in, revealing across the frame in that direction. |

- Choose a kind, then drag the **Duration** slider to set how long the overlap lasts (shown in seconds). The default is about half a second.
- Set it back to **None** to remove the transition.
- Transitions are **frame-accurate**: the transition lives on the outgoing clip and describes an *overlap* of N frames, so the two clips share their overlapping frames and the seam is exact. The slider can't exceed the shorter of the two clips, and very short overlaps (under 2 frames) are clamped so the crossfade can't desync.
- Audio across the seam gets an **equal-power crossfade** (constant power) — no pop, no volume dip as one clip hands off to the next.

If the panel says *"Place another clip next to this one on the same track to add a transition between them,"* there's no neighbor to transition into — line up a second clip on the same track first. And remember: **Close gaps** knows about transition overlaps and will never collapse one.

---

## Audio FX & mastering

CoreReflex gives you a **one-knob-per-effect** mastering rack — no audio-engineering degree required. The same rack runs in two places: on the **master bus** for the whole mix (covered here), and on **every individual clip** (covered just below). Open **Master Audio** and either start from a preset or drag a single slider per effect (each runs 0 = off up to 100).

### Start from a preset

One click dials a whole chain for a common job:

| Preset | Good for |
|---|---|
| **Podcast voice** | Spoken-word episodes — compression, de-essing, light denoise, a safe limiter, and a loudness lift. |
| **Dialogue** | Clean, consistent on-camera or narration dialogue. |
| **Clean voice** | A lighter touch — denoise + de-ess + gentle compression. |
| **Music master** | Music beds — compression, loudness, a ceiling, and a touch of warmth. |
| **Punchy** | Maximum impact — heavy compression and loudness. |

After applying a preset you can still tweak any individual knob.

### The effects, in plain language

| Effect | What the knob does |
|---|---|
| **Compress** | Evens out loud and quiet — punchier, more consistent. |
| **Limit** | Stops peaks from clipping — a safe ceiling. |
| **Clip** | Soft saturation — warmth and perceived loudness. |
| **Maximize** | Pushes overall loudness up. |
| **De-ess** | Tames harsh "sss" sibilance on voice. |
| **Denoise** | Reduces background hiss and hum. |
| **Reverb** | Adds space and depth. |

These are real audio processing, not a volume trick. The master rack lives on the whole mix and is **baked into your export** by a real audio-processing pass on the render service — so the master you ship sounds exactly like the preview. Use **Reset audio FX** to clear the rack and start over.

### Per-clip audio FX — the same rack on every clip

The mastering rack isn't just for the master bus. **Every audio-bearing clip carries its own copy of it** — a generated soundtrack, a voiceover, an uploaded audio file, *and* a video clip's own sound. Select a clip and open its **Audio FX** section in the inspector to get the identical chain: the same presets, the same seven one-knob effects, and the same **Reset audio FX**.

So you can master each element where it belongs — compress the voiceover, warm the music bed, de-ess a noisy clip — instead of fixing everything on the master bus. Per-clip FX and the master rack stack: a clip's own FX run first, then the whole mix passes through Master on the way out.

- **AI auto-master.** One click on **✨ AI auto-master** picks a sensible starting chain for the clip — it reads what the clip is (music vs. voice vs. general audio) and dials in *Music master*, *Dialogue*, or *Clean voice* to match. Tweak any knob from there.
- **You hear it in preview, and you get it in the export.** When you set FX on a clip, CoreReflex processes that clip's audio into a real, processed version and plays *that* in the preview player — the very same processed audio is what bakes into the render. Preview equals export, per clip.

> **Honest note.** Per-clip processing is real signal processing that runs on CoreReflex's audio service. If your workspace shows *"Audio mastering is being provisioned and is not available yet"* when you apply clip FX, that service hasn't been switched on for your deployment — the knobs and presets are saved with your project, but playback stays unprocessed until it is.

---

## Captions, subtitles & the transcript

Turn the spoken words in any clip into on-screen captions — for accessibility, silent-scroll social viewing, or that animated word-by-word look — then edit the *video* by editing the *text*.

### Generate captions

1. Select a video or audio clip and open its **Captions** section.
2. Click **Caption video** (or **Caption audio**). CoreReflex transcribes the clip with word-level timing and drops a caption layer directly above it on the timeline.
3. Need to re-do it? **Regenerate captions** re-runs the transcription. Very long clips exceed the captioning duration limit — caption them in sections.

### Style them

Start from a **one-click style preset**:

| Preset | The look |
|---|---|
| **Karaoke** | Big bold white text, a blue active-word highlight, word-by-word pop. |
| **Bold pop** | Single-line, extra-heavy, gold highlight — the maximum-energy social style. |
| **Minimal** | Clean medium-weight text with no stroke and a gentle rise animation. |
| **Subtitle** | Classic two-line broadcast subtitles. |

Then fine-tune anything in the inspector — font (TikTok Sans by default), size, position, line height, the number of lines on screen, how long each page of words stays up, stroke, an optional background pill, and the **highlight color** for the active word. The **Word animation** control sets how the active word enters: **None**, **Pop** (a quick scale-up), or **Rise** (settles in from just below). The animation renders in the export exactly as previewed.

### Translate them

Pick a language in the **Translate** control — Spanish, French, German, Portuguese, Italian, Japanese, Korean, Chinese, Hindi, or Arabic — and CoreReflex translates the captions while keeping their timing on the source timeline. The swap is one undoable commit: `Cmd/Ctrl+Z` restores the original language instantly.

### The transcript panel — edit video by editing text

Select a captions layer and open its **Transcript** section: the entire spoken track rendered as clickable text, the Descript-style workflow.

- **Click a word** to seek the player to the moment it's spoken.
- **Shift-click** a second word to select the whole run between them, then hit **Delete N words** — the source clip **ripples closed** and the captions compress in the same single undo step. Cutting a rambling sentence is now literally deleting a sentence.
- **Filler words are tinted** in the text automatically. One click on **Remove fillers (N)** or **Remove pauses (N)** cuts them all — same ripple, same caption sync, one undo entry.
- **✨ Find highlights** asks the AI to rank the transcript's best standalone moments — each comes back with a title, a score, a time range, and the reasoning (hover the title). Clicking one selects and seeks to it in the transcript.
- **✂ Keep only this** on a highlight cuts *everything outside that moment* — the composition ripples down to just the highlight, in one undoable step. It's the fastest path from a long recording to a short.
- **Export sidecar files:** download the captions as **SRT** or **WebVTT** for YouTube, players, and platforms that take sidecar subtitles. Translated captions download with the language in the filename.

If the panel says the captions aren't linked to their source clip (captions generated a while ago, before linking existed), regenerate the captions once to enable transcript editing.

---

## Rendering your master

When the edit is locked, hand the timeline off to render. Rendering is **live**: jobs run on CoreReflex's own self-hosted render service — no third-party render clouds anywhere in the path — and the finished file lands back in your workspace.

### Export with a platform preset

Open the **Export** section and pick where the piece is headed:

| Preset | Output |
|---|---|
| **YouTube** | MP4 (H.264), 16:9, auto-enhanced to at least 1080p. |
| **YouTube Shorts** | MP4 (H.264), vertical 9:16, auto-enhanced. |
| **TikTok** | MP4 (H.264), vertical 9:16, auto-enhanced. |
| **Instagram Reels** | MP4 (H.264), vertical 9:16, auto-enhanced. |
| **Instagram / LinkedIn feed** | MP4 (H.264), square 1:1, auto-enhanced. |
| **X (Twitter)** | MP4 (H.264), 16:9, auto-enhanced. |
| **Custom** | Pick your own container — MP4 (H.264) or WebM (VP8) — with no automatic enhancement. |

Each preset bundles the right container **and** an auto-enhance pass: if your finished master comes out below 1080p, it's upscaled to 1080p on CoreReflex's own upscaler before delivery. If your project's aspect ratio doesn't match the platform's native one (say, a 16:9 timeline exported for TikTok), the panel **warns you** — it never blocks, but [Auto-reframe](#auto-reframe-to-canvas) or the [Shorts Studio](#shorts-studio) is usually the better fix than letting the platform crop it.

### Trigger, watch, download

1. Click **Render video**. (The button is disabled while the timeline is empty.) Your timeline saves first, so the render service works from exactly the edit you see.
2. Watch the progress bar — the same job also shows in the studio's top progress line and activity log.
3. When it finishes you'll see the file size and a download link; the master is also served back through your workspace like any other asset.

### Quality, upscaling & watermarks

- **Upscale tiers.** The auto-enhance pass targets 1080p. Explicit targets — 720p, 1080p, 4K, and (opt-in) 8K — are supported by the render pipeline and available today through the CoreReflex developer API; the export presets in the editor use the automatic tier.
- **Watermarks.** Exports on the Free plan carry a small brand watermark; **Pro and Enterprise exports are clean**. The decision is made server-side at render time from your plan — see [Plans & Billing](plans-and-billing.md) for tiers and monthly export allowances.
- **Everything bakes in.** Color grades, transitions, keyframe animation, green-screen keys, captions with their word animations, and audio FX all render from the same timeline you previewed.

> If your deployment ever responds with *"Self-hosted export is being provisioned"*, the render service hasn't been switched on for that environment — you get a clear notice, never a job that silently hangs.

---

## Version history & comments

Two collaboration essentials live in the **Project** panel (deselect everything, or use the Project tab):

- **Version history.** Every save snapshots your project server-side. The panel lists the snapshots — open it to restore any earlier version. Restoring is itself versioned ("Before restore"), so you can always step back out of a restore.
- **Comments.** Leave and read timestamped comments on the project right in the studio — and for structured client review (tokenized share links, approve / request-changes, drawing on frames), send a proof instead. Both are covered in depth in [Proofing, Review & Collaboration](proofing-and-approvals.md).

---

## Shorts Studio

Repurpose a finished film into a vertical short without leaving the dashboard. Open **Shorts Studio** from the dashboard's **Shorts + captions** card, pick a finished film, choose **9:16** (TikTok / Reels / Shorts) or **1:1** (square feed), and press **Make short**.

CoreReflex re-frames the whole timeline with one uniform center-cover scale, so every clip — along with its captions, color grade, and audio effects — is carried over verbatim and only the geometry is rewritten. Caption and text sizes scale with the reframe (so they fit the new frame, not just the canvas), and if the source film already has captions they come along. The reframed short is a **brand-new project** that renders on the same live render service as everything else — make the short, and the export queues immediately.

For cutting shorts out of a *long recording* rather than reframing a finished film, start from **Find highlights** in the [transcript panel](#the-transcript-panel--edit-video-by-editing-text) or the dashboard's Auto-Clips studio.

---

## A few neighbors worth knowing

A few related tools sit next to the editor — some in this same inspector, some as self-contained studios on your dashboard — and are covered elsewhere:

- **Voiceover** — type a line, pick a cinematic voice, and drop narration straight onto the timeline. See [Voiceover & Music](voiceover-and-music.md).
- **Recreate with AI** — regenerate any clip in place with a new prompt; covered in [Directing Films](directing-films.md#recreate-any-clip).
- **Write a script — live.** The native **Script Studio** opens straight from the dashboard's *Write a script* card. Draft a script from a brief in a natural, spoken voice, rewrite any line to sound human, and save it to your workspace — no editor trip required.
- **Clone a persona.** The **Persona Studio** opens from the dashboard's *Clone a persona* card. Create a consented video clone — likeness **and** voice — attach reference media, and run the consent grant/revoke flow; a persona can never render until you record ownership consent (a hard gate). The final talking-head render rides a self-hosted lipsync engine that is still maturing — see [Coming Soon](coming-soon.md) for exactly where it stands. Persona is a Pro capability.

---

## Keyboard shortcut reference

| Keys | Does |
|---|---|
| `V` or `Esc` | Select tool |
| `B` or `C` | Blade (razor) tool |
| `M` | Drop a marker at the playhead |
| `Option/Alt + ←` / `→` | Jump to previous / next marker |
| `Shift+M` | Toggle snapping |
| Hold `Cmd/Ctrl` while dragging | Bypass snapping for that move |
| `[` / `]` | Nudge selection to previous / next grid line |
| `Q` / `W` | Trim selected clips' in / out point to the playhead |
| `Delete` / `Backspace` | Lift delete (leaves the gap) |
| `Shift + Delete` | Ripple delete (closes the gap) |
| `Option/Alt`-drag a clip edge | Ripple trim |
| `Option/Alt`-drag a clip body | Slip |
| `Option/Alt + Shift`-drag a clip body | Slide |
| `Cmd/Ctrl + Z` | Undo |
| `Cmd/Ctrl + S` | Save |

---

## Troubleshooting

- **A clip won't trim any further.** You've hit the end of the source material, or a neighbor — media clips can only show frames their file actually has. Slip the clip (⌥-drag its body) to use a different part of the source, or use **Extend with AI** to generate more.
- **Everything keeps sticking while I drag.** That's snapping. Hold `Cmd/Ctrl` to bypass it for one move, or press `Shift+M` to turn it off.
- **"Close gap after" doesn't appear in the right-click menu.** There's no gap after that clip — or what looks like a gap is actually a transition's overlap, which is protected on purpose.
- **The transcript panel says the captions aren't linked to their source clip.** They were generated before transcript editing existed. Click **Regenerate captions** once and the panel unlocks.
- **Auto-reframe says "Upload the clip first."** It reads a frame from the cloud copy of your video — wait for the upload to finish (watch the activity log), then retry.
- **The Curve tab says a preset "isn't a single bezier curve."** Bounce and Hold are special shapes without draggable handles. The graph still previews them exactly; pick any bezier preset to get handles back.
- **Applying clip audio FX shows "being provisioned."** The audio-processing service isn't switched on for your deployment yet. Your FX settings are saved with the project and will apply once it is.
- **My export has a watermark.** Free-plan exports are watermarked; upgrade to Pro for clean masters — see [Plans & Billing](plans-and-billing.md).

---

### Related guides

- [Directing Films](directing-films.md) — board, produce, and assemble shots with the agentic director before you edit.
- [Recording & Capture](recording-and-podcasts.md) — get footage onto the timeline.
- [Voiceover & Music](voiceover-and-music.md) — add narration and a score.
- [Proofing, Review & Collaboration](proofing-and-approvals.md) — comments, client review links, and approvals.
- [Plans & Billing](plans-and-billing.md) — watermark rules, export allowances, and tiers.