mpegts-demuxer/lib/classes/Stream.js

Demuxes an MPEG Transport Stream into elementary packets.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Stream = void 0;

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }

class Stream {
  constructor() {
    _defineProperty(this, "program", 0xffff);

    _defineProperty(this, "id", 0);

    _defineProperty(this, "type", 0xff);

    _defineProperty(this, "stream_id", 0);

    _defineProperty(this, "content_type", 0);

    _defineProperty(this, "dts", 0);

    _defineProperty(this, "has_dts", false);

    _defineProperty(this, "first_pts", 0);

    _defineProperty(this, "last_pts", 0);

    _defineProperty(this, "has_pts", false);

    _defineProperty(this, "frame_ticks", 0);

    _defineProperty(this, "frame_num", 0);

    _defineProperty(this, "payload", null);
  }

  finalize() {
    const {
      payload
    } = this;
    if (payload === null) return null;
    let data = new Uint8Array();

    if (payload.buffer.length === 1) {
      [data] = payload.buffer;
    } else {
      data = new Uint8Array(payload.buflen);
      let offset = 0;
      payload.buffer.forEach(b => {
        data.set(b, offset);
        offset += b.byteLength;
      });
    }

    return {
      data,
      pts: payload.pts,
      dts: payload.dts,
      frame_ticks: payload.frame_ticks,
      program: this.program,
      stream_number: this.id,
      stream_id: this.stream_id,
      type: this.type,
      content_type: this.content_type,
      frame_num: this.frame_num
    };
  }

  write(mem, ptr, len, pstart, copy) {
    const {
      payload
    } = this;
    let data = new Uint8Array(mem.buffer, mem.byteOffset + ptr, len);
    if (copy) data = data.slice();

    if (pstart || payload === null) {
      // finalize previously accumulated packet
      const packet = this.finalize(); // start new packet

      this.payload = {
        buffer: [data],
        buflen: len,
        pts: this.last_pts,
        dts: this.dts,
        frame_ticks: this.frame_ticks
      };
      return packet;
    }

    payload.buffer.push(data);
    payload.buflen += len;
    return null;
  }

}

exports.Stream = Stream;