function Cea608Channel(channelNumber, outputFilter, logger) {
    this.chNr = void 0;
    this.outputFilter = void 0;
    this.mode = void 0;
    this.verbose = void 0;
    this.displayedMemory = void 0;
    this.nonDisplayedMemory = void 0;
    this.lastOutputScreen = void 0;
    this.currRollUpRow = void 0;
    this.writeScreen = void 0;
    this.cueStartTime = void 0;
    this.logger = void 0;
    this.chNr = channelNumber;
    this.outputFilter = outputFilter;
    this.mode = null;
    this.verbose = 0;
    this.displayedMemory = new CaptionScreen(logger);
    this.nonDisplayedMemory = new CaptionScreen(logger);
    this.lastOutputScreen = new CaptionScreen(logger);
    this.currRollUpRow = this.displayedMemory.rows[NR_ROWS - 1];
    this.writeScreen = this.displayedMemory;
    this.mode = null;
    this.cueStartTime = null; // Keeps track of where a cue started.

    this.logger = logger;
  }
Get all non-empty rows with as unicode text.