fis_lib_vid/lib/processors/brightness.dart

import 'dart:typed_data';

import 'base.dart';

/// Vid亮度处理器
class VidBrightnessProcessor extends VidFrameProcessor {
  VidBrightnessProcessor(this.brightness) {
    _setActualBrightness();
  }

  /// 亮度 [-255~255]
  final int brightness;

  late final int _actualBrightness;

  void _setActualBrightness() {
    if (brightness < -255) {
      _actualBrightness = -255;
    } else if (brightness > 255) {
      _actualBrightness = 255;
    } else {
      _actualBrightness = brightness;
    }
  }

  @override
  Uint8List process(Uint8List bytes, int position) {
    final i = position;
    final _brightness = _actualBrightness;

    int b = bytes[i];
    int g = bytes[i + 1];
    int r = bytes[i + 2];

    b += _brightness;
    g += _brightness;
    r += _brightness;

    if (b < 0) b = 0;
    if (b > 255) b = 255;
    if (g < 0) g = 0;
    if (g > 255) g = 255;
    if (r < 0) r = 0;
    if (r > 255) r = 255;

    bytes[i] = b;
    bytes[i + 1] = g;
    bytes[i + 2] = r;

    return bytes;
  }

  @override
  String toString() => 'VidBrightnessProcessor: $brightness';
}