@svta/common-media-library
Version:
A common library for media playback in JavaScript
267 lines • 10.8 kB
JavaScript
"use strict";
/**
*
* This code was ported from the dash.js project at:
* https://github.com/Dash-Industry-Forum/dash.js/blob/development/externals/cea608-parser.js
* https://github.com/Dash-Industry-Forum/dash.js/commit/8269b26a761e0853bb21d78780ed945144ecdd4d#diff-71bc295a2d6b6b7093a1d3290d53a4b2
*
* The original copyright appears below:
*
* The copyright in this software is being made available under the BSD License,
* included below. This software may be subject to other third party and contributor
* rights, including patent rights, and no such rights are granted under this license.
*
* Copyright (c) 2015-2016, DASH Industry Forum.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation and/or
* other materials provided with the distribution.
* 2. Neither the name of Dash Industry Forum nor the names of its
* contributors may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS AS IS AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.Cta608Channel = void 0;
const CaptionScreen_js_1 = require("./CaptionScreen.js");
const CaptionsLogger_js_1 = require("./CaptionsLogger.js");
const VerboseLevel_js_1 = require("./VerboseLevel.js");
const NR_ROWS_js_1 = require("./utils/NR_ROWS.js");
/**
* CTA-608 Channel
*
* @group CTA-608
* @beta
*/
class Cta608Channel {
constructor(channelNumber, outputFilter, logger = new CaptionsLogger_js_1.CaptionsLogger()) {
this.chNr = channelNumber;
this.outputFilter = outputFilter;
this.mode = null;
this.displayedMemory = new CaptionScreen_js_1.CaptionScreen(logger);
this.nonDisplayedMemory = new CaptionScreen_js_1.CaptionScreen(logger);
this.lastOutputScreen = new CaptionScreen_js_1.CaptionScreen(logger);
this.currRollUpRow = this.displayedMemory.rows[NR_ROWS_js_1.NR_ROWS - 1];
this.writeScreen = this.displayedMemory;
this.mode = null;
this.cueStartTime = null; // Keeps track of where a cue started.
this.logger = logger;
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'new Cea608Channel(' + this.chNr + ')');
}
reset() {
var _a, _b;
this.mode = null;
this.displayedMemory.reset();
this.nonDisplayedMemory.reset();
this.lastOutputScreen.reset();
(_b = (_a = this.outputFilter) === null || _a === void 0 ? void 0 : _a.reset) === null || _b === void 0 ? void 0 : _b.call(_a);
this.currRollUpRow = this.displayedMemory.rows[NR_ROWS_js_1.NR_ROWS - 1];
this.writeScreen = this.displayedMemory;
this.mode = null;
this.cueStartTime = null;
}
getHandler() {
return this.outputFilter;
}
setHandler(outputFilter) {
this.outputFilter = outputFilter;
}
setPAC(pacData) {
this.writeScreen.setPAC(pacData);
}
setBkgData(bkgData) {
this.writeScreen.setBkgData(bkgData);
}
setMode(newMode) {
if (newMode === this.mode) {
return;
}
this.mode = newMode;
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, () => 'MODE=' + newMode);
if (this.mode === 'MODE_POP-ON') {
this.writeScreen = this.nonDisplayedMemory;
}
else {
this.writeScreen = this.displayedMemory;
this.writeScreen.reset();
}
if (this.mode !== 'MODE_ROLL-UP') {
this.displayedMemory.setRollUpRows(null);
this.nonDisplayedMemory.setRollUpRows(null);
}
this.mode = newMode;
}
insertChars(chars) {
for (let i = 0; i < chars.length; i++) {
this.writeScreen.insertChar(chars[i]);
}
const screen = this.writeScreen === this.displayedMemory ? 'DISP' : 'NON_DISP';
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, () => screen + ': ' + this.writeScreen.getDisplayText(true));
if (this.mode === 'MODE_PAINT-ON' || this.mode === 'MODE_ROLL-UP') {
this.logger.log(VerboseLevel_js_1.VerboseLevel.TEXT, () => 'DISPLAYED: ' + this.displayedMemory.getDisplayText(true));
this.outputDataUpdate();
}
}
ccRCL() {
// Resume Caption Loading (switch mode to Pop On)
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'RCL - Resume Caption Loading');
this.setMode('MODE_POP-ON');
}
ccBS() {
// BackSpace
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'BS - BackSpace');
if (this.mode === 'MODE_TEXT') {
return;
}
this.writeScreen.backSpace();
if (this.writeScreen === this.displayedMemory) {
this.outputDataUpdate();
}
}
ccAOF() {
// Reserved (formerly Alarm Off)
}
ccAON() {
// Reserved (formerly Alarm On)
}
ccDER() {
// Delete to End of Row
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'DER- Delete to End of Row');
this.writeScreen.clearToEndOfRow();
this.outputDataUpdate();
}
ccRU(nrRows) {
// Roll-Up Captions-2,3,or 4 Rows
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'RU(' + nrRows + ') - Roll Up');
this.writeScreen = this.displayedMemory;
this.setMode('MODE_ROLL-UP');
this.writeScreen.setRollUpRows(nrRows);
}
ccFON() {
// Flash On
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'FON - Flash On');
this.writeScreen.setPen({ flash: true });
}
ccRDC() {
// Resume Direct Captioning (switch mode to PaintOn)
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'RDC - Resume Direct Captioning');
this.setMode('MODE_PAINT-ON');
}
ccTR() {
// Text Restart in text mode (not supported, however)
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'TR');
this.setMode('MODE_TEXT');
}
ccRTD() {
// Resume Text Display in Text mode (not supported, however)
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'RTD');
this.setMode('MODE_TEXT');
}
ccEDM() {
// Erase Displayed Memory
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'EDM - Erase Displayed Memory');
this.displayedMemory.reset();
this.outputDataUpdate(true);
}
ccCR() {
// Carriage Return
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'CR - Carriage Return');
this.writeScreen.rollUp();
this.outputDataUpdate(true);
}
ccENM() {
// Erase Non-Displayed Memory
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'ENM - Erase Non-displayed Memory');
this.nonDisplayedMemory.reset();
}
ccEOC() {
// End of Caption (Flip Memories)
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'EOC - End Of Caption');
if (this.mode === 'MODE_POP-ON') {
const tmp = this.displayedMemory;
this.displayedMemory = this.nonDisplayedMemory;
this.nonDisplayedMemory = tmp;
this.writeScreen = this.nonDisplayedMemory;
this.logger.log(VerboseLevel_js_1.VerboseLevel.TEXT, () => 'DISP: ' + this.displayedMemory.getDisplayText());
}
this.outputDataUpdate(true);
}
ccTO(nrCols) {
// Tab Offset 1,2, or 3 columns
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'TO(' + nrCols + ') - Tab Offset');
this.writeScreen.moveCursor(nrCols);
}
ccMIDROW(secondByte) {
// Parse MIDROW command
const styles = { flash: false };
styles.underline = secondByte % 2 === 1;
styles.italics = secondByte >= 0x2e;
if (!styles.italics) {
const colorIndex = Math.floor(secondByte / 2) - 0x10;
const colors = [
'white',
'green',
'blue',
'cyan',
'red',
'yellow',
'magenta',
];
styles.foreground = colors[colorIndex];
}
else {
styles.foreground = 'white';
}
this.logger.log(VerboseLevel_js_1.VerboseLevel.INFO, 'MIDROW: ' + JSON.stringify(styles));
this.writeScreen.setPen(styles);
}
outputDataUpdate(dispatch = false) {
const time = this.logger.time;
if (time === null) {
return;
}
if (this.outputFilter) {
if (this.cueStartTime === null && !this.displayedMemory.isEmpty()) {
// Start of a new cue
this.cueStartTime = time;
}
else {
if (!this.displayedMemory.equals(this.lastOutputScreen)) {
this.outputFilter.newCue(this.cueStartTime, time, this.lastOutputScreen);
if (dispatch && this.outputFilter.dispatchCue) {
this.outputFilter.dispatchCue();
}
this.cueStartTime = this.displayedMemory.isEmpty() ? null : time;
}
}
this.lastOutputScreen.copy(this.displayedMemory);
}
}
cueSplitAtTime(t) {
if (this.outputFilter) {
if (!this.displayedMemory.isEmpty()) {
if (this.outputFilter.newCue) {
this.outputFilter.newCue(this.cueStartTime, t, this.displayedMemory);
}
this.cueStartTime = t;
}
}
}
}
exports.Cta608Channel = Cta608Channel;
//# sourceMappingURL=Cta608Channel.js.map