Mix (Cross Dissolve) — effect skill for transitions

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The two shots blend through each other. The quietest transition: "time passes" or "this continues".

What it does

Built on Fade Through by HeyGen (HyperFrames), Apache-2.0. The write-up and recipes below are varg's.

A fades out while B fades in over the same frames; halfway both are at 50%.

When: Time passing, calm brand and wellness pieces, slideshow photos, soft scene changes.

Watch out: Mixing between two busy shots makes mud; never use it to hide a weak cut in fast edits.

Timing: 0.4–1.0 s (CapCut Mix default 1.0 s, a short Mix 0.47 s), linear or ease-in-out

Also called: Mix, Dissolve, crossfade, cross dissolve, fade

In FFmpeg

Same size/fps/pixel format on both inputs (see the Normalize card). offset = duration(A) - T = 5.0 - 0.5 = 4.5.

ffmpeg -i a.mp4 -i b.mp4 -filter_complex \
"[0:v]fps=30,settb=AVTB,format=yuv420p[a];[1:v]fps=30,settb=AVTB,format=yuv420p[b];\
[a][b]xfade=transition=fade:duration=0.5:offset=4.5[v];\
[0:a][1:a]acrossfade=d=0.5[au]" \
  -map "[v]" -map "[au]" -c:v libx264 -crf 18 -c:a aac out.mp4

dissolve is a different, dithered (noisy) dissolve; fadefast/fadeslow change the curve.

In HyperFrames

Shader cross-warp-morph from @hyperframes/shader-transitions placed at the cut (t = 4 s):

<div id="s1" class="scene" style="background:#0a0a0a"><video src="a.mp4" muted playsinline></video></div>
<div id="s2" class="scene" style="background:#0a0a0a"><video src="b.mp4" muted playsinline></video></div>
<script src="https://cdn.jsdelivr.net/npm/@hyperframes/shader-transitions/dist/index.global.js"></script>
<script>
  const tl = HyperShader.init({ bgColor: "#0a0a0a", scenes: ["s1", "s2"],
    transitions: [{ time: 4, shader: "cross-warp-morph", duration: 0.8 }] });
  window.__timelines = window.__timelines || {}; window.__timelines["main"] = tl;
</script>

Each .scene needs an explicit background-color equal to bgColor. Plain CSS crossfade: omit shader in that transition entry, or overlap two clips by 0.5 s and tween opacity (see the HyperFrames scene transition card).

In Remotion

import {TransitionSeries, linearTiming, springTiming} from '@remotion/transitions';
import {fade} from '@remotion/transitions/fade';

<TransitionSeries>
  <TransitionSeries.Sequence durationInFrames={90}><ShotA /></TransitionSeries.Sequence>
  <TransitionSeries.Transition presentation={fade()} timing={linearTiming({durationInFrames: 15})} />
  <TransitionSeries.Sequence durationInFrames={90}><ShotB /></TransitionSeries.Sequence>
</TransitionSeries>

Total = 90 + 90 - 15 frames: the transition overlaps the two shots.

In CapCut

Transitions tab → Basic / Overlay → Mix, Dissolve, Dissolve II/III. Desktop: drag the tile onto the cut between two clips and set Duration in the right panel ("Apply to all" reuses it on every cut). Mobile: tap the small white square between clips, pick the transition, drag the duration slider, tap ✓. Tab labels and placement change between versions and regions.

Ready-made components

Where this comes from

Use when

Not for

Install

Example output

https://s3.varg.ai/how-to/previews/22b4c9523412/take-mix-dissolve.mp4 — fade between two shots, with the timeline strip of the edit. Footage: Big Buck Bunny (2008), (c) copyright 2008, Blender Foundation | www.bigbuckbunny.org, CC BY 3.0; WING IT! (2023), Blender Studio | studio.blender.org, CC BY 4.0. (credit: Rendered by varg · Big Buck Bunny (2008) + WING IT! (2023))

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