PictureInPicture

The key topology correction is that PictureInPicture does not take separate Background and Foreground images like Merge. Blackmagic's official workflow applies the effect to the upper clip that should become the smaller window while the full-frame background stays on the lower track. In Fusion terms: inset source → PictureInPicture → Merge.Foreground, main plate → Merge.Background.

Picture in Picture is a dedicated Resolve FX added in DaVinci Resolve 21. Resolve 20 and earlier tutorials therefore commonly build the same visual manually with Transform/Crop/Merge or use Video Collage; do not imply that the dedicated effect exists in those older versions.

Content controls only the source inside the window. Zoom reframes scale inside a fixed card, Pan changes horizontal framing and Tilt changes vertical framing. These controls should not be substituted for Position X/Y or Width/Height.

Position controls the PiP container itself. Position X/Y place the outer window and Width/Height define its dimensions. Lock Aspect Ratio is visible in the current Resolve 21 UI and supports proportional resizing.

Style should be addressed after framing and geometry are understood. Rounding shapes the corners, Rotation turns the whole card and Opacity changes the visibility of the finished PiP element.

Border is a separately enabled styling layer. Border Width defines thickness, Border Color defines color and Border Opacity defines border transparency. Color-picker RGB components should not be promoted into separate Picture in Picture parameters.

Fill is not a second video input and not the composition background. It is a colored background inside the PiP window that becomes visible behind transparent source content. With fully opaque video its contribution may be hard to see.

Fill Matches Border is documented as setting the window background to the same color as Border Color. Do not broaden that statement into automatic inheritance of every border property, such as opacity, without direct UI evidence.

Drop Shadow has its own enable plus Strength, Color, Drop Angle, Drop Distance, Expand and Blur. The shadow separates the card from the underlying frame but does not replace good placement, safe areas or contrast management.

Expand changes the shadow footprint: Blackmagic describes it as growing or shrinking the drop shadow. It is not another Width/Height control and does not resize the source matte.

Use Alpha is a documented compositing control. It tells the effect to use its alpha channel for compositing, making alpha part of the functional contract rather than an incidental technical detail.

On the Color page Blackmagic notes that a stand-alone Picture in Picture node initially shows black around the card; an Alpha Output must be added and the PiP node's blue alpha output connected to it so the timeline receives transparency. In Fusion the equivalent diagnostic habit is to inspect PiP Alpha and use the RGBA result as Merge foreground.

An Effect Mask on the Fusion-hosted Resolve FX node limits where the effect is applied. It is not a second image source and does not turn PictureInPicture into a compositor.

Open FX Overlay on Edit/Color can move, resize and adjust the PiP interactively in the Viewer. A Fusion article should still explain the same control hierarchy through the Inspector even when page-specific interactive overlays differ.

Blackmagic documents Rounding from square corners at 0 toward a circular maximum at 1. On a non-square Width/Height this is still a rounded rectangle, so the word circle should not be read as forcing any aspect ratio into a perfect circle.

Rotation belongs to the outer card while Tilt belongs to vertical Content framing. This distinction matters because the word Tilt can otherwise be misread as an angular rotation of the source.

Card Opacity, Border Opacity and Fill Opacity are different levels. Reducing overall Opacity when only the border should fade also weakens the inset video itself.

For a single designed inset, PictureInPicture is usually simpler than Video Collage. For multiple coordinated tiles, grids and staggered layout animation, Video Collage is the more appropriate tool.

Complex tracked frames, arbitrary masks, deformable surface replacement or bespoke motion-graphics systems still belong to ordinary Fusion graphs. PictureInPicture is a fast production tool for a common inset, not a universal replacement for Merge, Transform and masks.

Review the result in motion and over multiple background frames. A border/shadow that reads on one still may disappear over another, and Content framing may fail later when a person or interface moves.

This article is anchored to the Resolve 21 reference. Exact defaults and common OpenFX controls may shift across builds, so the page documents verified control roles rather than treating values from one screenshot as universal defaults.