react-native-vision-camera/src/frame-processors/withFrameRefCounting.ts

A powerful, high-performance React Native Camera library.

import type { Frame, FrameInternal } from '../types/Frame'
import { throwErrorOnJS } from './throwErrorOnJS'

/**
 * A private API to wrap a Frame Processor with a ref-counting mechanism
 * @worklet
 * @internal
 */
export function withFrameRefCounting(frameProcessor: (frame: Frame) => void): (frame: Frame) => void {
  return (frame) => {
    'worklet'
    // Increment ref-count by one
    const internal = frame as FrameInternal
    internal.incrementRefCount()
    try {
      // Call sync frame processor
      frameProcessor(frame)
    } catch (e) {
      // Re-throw error on JS Thread
      throwErrorOnJS(e)
    } finally {
      // Potentially delete Frame if we were the last ref (no runAsync)
      internal.decrementRefCount()
    }
  }
}