Added seek mode option in stream

play-dl/YouTube/classes/SeekStream.ts

@@ -1,5 +1,4 @@
 import { IncomingMessage } from "http";
-import { Readable } from "stream";
 import { request_stream } from "../../Request";
 import { parseAudioFormats, StreamOptions, StreamType } from "../stream";
 import { video_info } from "../utils";
@@ -7,11 +6,11 @@ import { Timer } from "./LiveStream";
 import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
 
 /**
- * YouTube Stream Class for playing audio from normal videos.
+ * YouTube Stream Class for seeking audio to a timeStamp.
  */
  export class SeekStream {
     /**
-     * Readable Stream through which data passes
+     * WebmSeeker Stream through which data passes
      */
     stream: WebmSeeker;
     /**
@@ -69,7 +68,7 @@ import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
         video_url: string,
         options: StreamOptions
     ) {
-        this.stream = new WebmSeeker({ highWaterMark: 5 * 1000 * 1000, readableObjectMode : true });
+        this.stream = new WebmSeeker({ highWaterMark: 5 * 1000 * 1000, readableObjectMode : true, mode : options.mode });
         this.url = url;
         this.quality = options.quality as number;
         this.type = StreamType.Opus;
@@ -88,9 +87,16 @@ import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
         });
         this.seek(options.seek!)
     }
-
-    private seek(ms : number){
-        return new Promise(async(res) => {
+    /**
+     * **INTERNAL Function**
+     * 
+     * Uses stream functions to parse Webm Head and gets Offset byte to seek to.
+     * @param sec No of seconds to seek to
+     * @returns Nothing
+     */
+    private async seek(sec : number){
+        await new Promise(async(res) => {
+            if(!this.stream.headerparsed){
                 const stream = await request_stream(this.url, {
                     headers: {
                         range: `bytes=0-1000`
@@ -110,8 +116,13 @@ import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
 
                 stream.once('end', () => {
                     this.stream.state = WebmSeekerState.READING_DATA
+                    res('')  
+                })
+            }
+            else res('')  
+        })
 
-                const bytes = this.stream.seek(ms)
+        const bytes = this.stream.seek(sec)
         if (bytes instanceof Error) {
             this.stream.emit('error', bytes);
             this.bytes_count = 0;
@@ -120,12 +131,10 @@ import { WebmSeeker, WebmSeekerState } from "./WebmSeeker";
             return;
         }
 
+        this.stream.seekfound = false
         this.bytes_count = bytes
         this.timer.reuse()
         this.loop()
-                res('')          
-            })
-        })
     }
     /**
      * Retry if we get 404 or 403 Errors.

play-dl/YouTube/classes/WebmSeeker.ts

@@ -8,25 +8,35 @@ export enum WebmSeekerState{
     READING_DATA = 'READING_DATA',
 }
 
+interface WebmSeekerOptions extends DuplexOptions{
+    mode? : "precise" | "granular"
+}
+
 export class WebmSeeker extends Duplex{
     remaining? : Buffer
     state : WebmSeekerState
+    mode : "precise" | "granular"
     chunk? : Buffer
     cursor : number
     header : WebmHeader
     headfound : boolean
+    headerparsed : boolean
+    time_left : number
     seekfound : boolean
     private data_size : number
     private data_length : number
 
-    constructor(options? : DuplexOptions){
+    constructor(options : WebmSeekerOptions){
         super(options)
         this.state = WebmSeekerState.READING_HEAD
         this.cursor = 0
         this.header = new WebmHeader()
         this.headfound = false
+        this.time_left = 0
+        this.headerparsed = false
         this.seekfound = false
         this.data_length = 0
+        this.mode = options.mode || "granular"
         this.data_size = 0
     }
 
@@ -58,9 +68,10 @@ export class WebmSeeker extends Duplex{
 
     _read() {}
 
-    seek(ms : number): Error | number{
+    seek(sec : number): Error | number{
         let position = 0
-        let time = (Math.floor(ms / 10) * 10)
+        let time = (Math.floor(sec / 10) * 10)
+        this.time_left = (sec - time) * 1000 || 0
         if (!this.header.segment.cues) return new Error("Failed to Parse Cues")
 
         for(const data of this.header.segment.cues){
@@ -172,6 +183,10 @@ export class WebmSeeker extends Duplex{
             else this.cursor += this.data_size + this.data_length
 
             if(ebmlID.name === 'simpleBlock'){
+                if(this.time_left !== 0 && this.mode === "precise"){
+                    if(data.readUInt16BE(1) === this.time_left) this.time_left = 0
+                    else continue;
+                }
                 const track = this.header.segment.tracks![this.header.audioTrack]
                 if(!track || track.trackType !== 2) return new Error("No audio Track in this webm file.")
                 if((data[0] & 0xf) === track.trackNumber) this.push(data.slice(4))

play-dl/YouTube/stream.ts

@@ -12,6 +12,7 @@ export enum StreamType {
 }
 
 export interface StreamOptions {
+    mode? : "precise" | "granular"
     seek? : number
     quality?: number;
     htmldata?: boolean;