A picture-in-picture is really just layer stacking plus mask control. Shrink one photo inside another, use a mask and a drop shadow for depth, and it reads as a photo inside a photo. Good for covers and social images, and not hard to do.
Step 1: Open your photo
Open Online PS (zaixianps.cc) and click File → Open in the top-left (or just drag the image into the workspace).
Step 2: Duplicate the Background layer
In the Layers panel on the right, select the default Background layer.
Drag that layer onto the “Add new layer” icon at the bottom of the panel (it looks like a small sheet of paper).
The copy appears above the original and is named Background copy by default.
Step 3: Rename the copy to “Small”
Double-click the name Background copy, change it to Small and press Enter.
Step 4: Hide the Small layer
Click the eye icon in front of Small to hide it (we don't need it visible just yet).
Step 5: Select the Background layer
Make sure the original Background layer is still selected (it's the one we'll convert to black and white).
Step 6: Add a Black & White adjustment layer
At the bottom of the Layers panel, click the “New Fill or Adjustment Layer” icon (the half circle) and pick Black & White from the list.
A new Black & White 1 adjustment layer appears between Background and Small — it only affects the background below it.
Step 7: Click the “Auto” button
In the Properties panel on the right (open by default), find the “Auto” button and click it once.
Photoshop assigns a sensible slider value to each colour channel so the black-and-white result looks natural.
Step 8: Show the Small layer again
Back in the Layers panel, click the eye icon in front of Small to show it again.
The original colour image reappears, now sitting on top of the black-and-white background.
Step 9: Pick the Rectangle tool
In the toolbar on the left, find the Rectangle tool (shortcut U). Be careful not to hit the “Rectangular Marquee” above it — we want the shape tool.
Step 10: Set the mode to “Shape”
In the options bar at the top of the page, switch Mode to Shape (not Path or Pixels).
Step 11: Change the colour to black
Click the Fill colour swatch in the toolbar to open the colour picker.
Set R, G and B all to 0 and confirm — that's pure black.
Step 12: Turn the stroke off
Shapes carry a 1px black stroke by default. Click the Stroke colour swatch, choose None (the slashed icon) at the top left and press Enter.
Step 13: Draw the shape frame
Click the top-left corner of the canvas as your starting point, hold the mouse and drag to the bottom-right to draw a rectangle. Release to finish.
To move the shape while drawing, hold the space bar and drag.
Step 14: Resize the shape if you need to
Because the shape completely covers the image behind it, you can drop its opacity to 50% while adjusting (select the shape layer and press 5).
Then drag the corner handles to scale it, and press 0 to restore full opacity when you're happy.
Step 15: Drag the Small layer above the shape
In the Layers panel, drag Small above Rectangle 1 (the shape layer). A blue indicator line appears when the position is right.
Step 16: Create a clipping mask
With Small still selected, open the layer menu at the top right of the panel (three lines) and choose Create Clipping Mask (or just press Alt+Ctrl+G / Option+Cmd+G).
The colour Small layer is now cropped to the rectangle, leaving only the black-and-white background around it.
Step 17: Select the shape layer
In the Layers panel, click Rectangle 1 (the shape layer); next we'll give it a stroke and a shadow.
Step 18: Add a white stroke
At the bottom of the Layers panel, click the Layer Style (fx) icon and choose Stroke.
In the dialog that appears:
- Colour: click the swatch, R=255, G=255, B=255 → white.
- Position: Inside, so the border hugs the inside of the shape.
- Size: adjust to the image; here I use 40 px.
Step 19: Add a Drop Shadow
Still in the Layer Style dialog, choose Drop Shadow and set:
- Angle: 135° (light from the upper left)
- Distance: 50 px
- Size (feather): 15 px
- Opacity: 35 %
Click OK to save.
Step 20: Rotate the shape (optional)
Make sure Rectangle 1 is still selected and the Rectangle tool is still active.
Put the cursor just outside a corner of the shape; it turns into a rotate icon with curved arrows at both ends.
Click and drag to rotate. The colour layer inside keeps its orientation — only the frame turns.
Step 21: Final tweaks
Check that no important subject is cropped or hidden by the shadow; if it is, drag the shape handles again or re-adjust the stroke and shadow values.
When you're happy, press Enter (Win) / Return (Mac) to confirm and leave the edit.
Finally save the result with File → Export As → PNG/JPEG.
💡 Tip: want several picture-in-picture frames at once? Duplicate the shape (Ctrl+J), then point each copy's clipping mask at a different colour layer.
References
- Adobe Photoshop official documentation
- HTML5 and modern front-end image processing
- Online PS