camera_avfoundation_frame #

The iOS implementation of the camera plugin.

This package provides low-level camera access for the iOS platform using AVFoundation, and is used internally by the camera plugin.

🚀 New Feature: Capture Preview Frame (JPEG) #

This version introduces a new platform method: capturePreviewFrameJpeg(outputPath) for retrieving a single JPEG-compressed frame directly from the preview stream, without interrupting camera operation.

✅ Use Cases #

• Fast preview snapshot capture
• Save current frame to file instantly
• Frame grab for machine learning or inference
• Lightweight visual logging or scanning

📸 One-time Preview Frame (YUV) #

To capture a single frame (non-streaming) in YUV format:

final CameraImageData frame = await cameraController.capturePreviewFrame();
// Access .planes, .width, .height, .format, etc.

🖼 One-time Preview Frame (JPEG) #

To capture and save a JPEG-compressed preview frame to file:

final String savedPath = await cameraController.capturePreviewFrameJpeg('/path/to/file.jpg');

🛠 How It Works #

• Captures pixel buffer using AVCaptureVideoDataOutput
• Converts CVPixelBuffer (YUV or BGRA) to CIImage
• Applies optional rotation
• Encodes as JPEG with 90% quality using UIImageJPEGRepresentation
• Frame capture does not interrupt preview or video recording

❗️Notes #

• capturePreviewFrameJpeg does not trigger autofocus or shutter
• JPEG quality defaults to 90
• Supported formats: kCVPixelFormatType_420YpCbCr8BiPlanarFullRange, kCVPixelFormatType_32BGRA
• Supported on iOS 11+