Feature Request

Description

It'd be useful to have an option in CameraPreview.start() that removes letterboxing. This option would scale the image up so that no letterboxing is visible.

Platform(s)

iOS, Android, Web

Preferred Solution

A new option aspectMode: 'cover' | 'contain' could be added to CameraPreviewOptions, defaulting to 'contain', which is the current behavior.

Setting it to 'cover' removes letterboxing. Please see suggested implementation under Additional Context.

Additional Context

iOS

The preview is an AVCaptureVideoPreviewLayer. To fill without bars you set:
videoGravity = .resizeAspectFill

(Instead of .resizeAspect, which produces letterboxing.)

Android

The preview is a TextureView/SurfaceView driven by CameraX/Camera2. You need the equivalent “scale to fill” behavior:

• adjust the preview view's scale / transform matrix, or
• use a PreviewView scale type that fills (when using CameraX PreviewView), or
• compute a transform so the preview fills and crops.

Web

Simply add the following CSS to the <video> element when aspectMode is 'cover': object-fit: cover.