WIP 708 caption logging

708-caption-logger.js

@@ -0,0 +1,20 @@
+const fs = require('fs');
+const mp4 = require('./lib/mp4');
+const file = fs.readFileSync(process.argv[2] || './bad-708.ts');
+
+// https://github.com/google/ExoPlayer/blob/16b51d689c6a1a5ec327d1977a5fe8de9fefe41e/library/core/src/main/java/com/google/android/exoplayer2/text/cea/Cea708Decoder.java#L529
+const transmuxer = new mp4.Transmuxer();
+
+// Setting the BMDT to ensure that captions and id3 tags are not
+// time-shifted by this value when they are output and instead are
+// zero-based
+transmuxer.setBaseMediaDecodeTime(100000);
+
+transmuxer.on('data', function(data) {
+  if (data.captions) {
+    console.log(data.captions);
+  }
+});
+
+transmuxer.push(file);
+transmuxer.flush();

lib/m2ts/caption-stream.js

@@ -17,6 +17,97 @@
 // Link To Transport
 // -----------------
 
+const handleC0 = function(command) {
+  // Nul
+  if (command === 0x00) {
+    // do nothing
+    //console.log('c0 NUL')
+  } else if (command === 0x03) {
+    //console.log('c0 EXT');
+  } else if (command === 0x08) {
+    //console.log('c0 Backspace');
+    process.stdout.moveCursor(-1);
+    process.stdout.clearLine(1)
+  } else if (command === 0x0C) {
+    //console.log('c0 Formfeed');
+  } else if (command === 0x0D) {
+    //console.log('c0 CarriageReturn');
+  } else if (command === 0x0E) {
+    //console.log('c0 ClearLine');
+  } else {
+    if (command >= 0x11 && command <= 0x17) {
+      //console.log('c0 EXT1');
+    } else if (command >= 0x18 && command <= 0x1f) {
+      //console.log('c0 P16');
+    } else {
+      //console.log('c0 invalid command')
+    }
+  }
+
+};
+
+const handleC1 = function(command) {
+  if (command >= 0x80 && command <= 0x87) {
+    //console.log('C1 set current window CW' + (command - 0x80));
+  } else if (command === 0x88) {
+    //console.log('C1 CLW (clearWindows)');
+    return 1;
+  } else if (command === 0x89) {
+    //console.log('C1 DSW (displayWindows)');
+    return 1;
+  } else if (command === 0x8A) {
+    //console.log('C1 HDW (hideWindows)');
+    return 1;
+  } else if (command === 0x8b) {
+    //console.log('C1 TGW (toggleWindows)');
+    return 1;
+  } else if (command === 0x8c) {
+    //console.log('C1 DLW (deleteWindows)');
+    return 1;
+  } else if (command === 0x8D) {
+    //console.log('C1 DLY (delay)');
+    return 1;
+  } else if (command === 0x8E) {
+    //console.log('C1 DLC (delay cancel)');
+  } else if (command === 0x8F) {
+    //console.log('C1 RST (reset)');
+  } else if (command === 0x90) {
+    //console.log('C1 SPA (set pen attributes)');
+    return 2;
+  } else if (command === 0x91) {
+  // console.log('C1 SPC (set pen color)')
+    return 3;
+  } else if (command === 0x92) {
+    // console.log('C1 SPL (set pen location)');
+    return 2;
+  } else if (command === 0x97) {
+    // console.log('C1 SWA (set window attributes)');
+    return 4;
+  } else if (command >= 0x98 && command <= 0x9F) {
+    // console.log('C1 DF' + (command - 0x98) +  '(define window)');
+    return 6;
+  } else {
+    // console.log('C1 invalid command');
+  }
+};
+
+const handleG0 = function(command) {
+  let str = String.fromCharCode(command & 0xFF);
+
+  if (command === 0x7F) {
+    str = String.fromCharCode(0x266a);
+  }
+
+  //console.log('G0 ' + command.toString(16) + ' ' + str );
+  process.stdout.write(str);
+};
+
+const handleG1 = function(command) {
+  //console.log('G1 ' + command.toString(16) + ' ' + String.fromCharCode(command));
+  process.stdout.write(String.fromCharCode(command));
+};
+
+
 var Stream = require('../utils/stream');
 var cea708Parser = require('../tools/caption-packet-parser');
 
@@ -493,6 +584,7 @@ Cea708Stream.prototype.add708Bytes = function(packet) {
   var data = packet.ccData;
   var byte0 = data >>> 8;
   var byte1 = data & 0xff;
+  debugger;
 
   // I would just keep a list of packets instead of bytes, but it isn't clear in the spec
   // that service blocks will always line up with byte pairs.
@@ -513,7 +605,7 @@ Cea708Stream.prototype.push708Packet = function() {
   var b = packetData[i++];
 
   packet708.seq = b >> 6;
-  packet708.sizeCode = b & 0x3f; // 0b00111111;
+  packet708.sizeCode = (b & 0x3f) * 2 - 1; // 0b00111111;
 
   for (; i < packetData.length; i++) {
     b = packetData[i++];
@@ -529,7 +621,7 @@ Cea708Stream.prototype.push708Packet = function() {
     this.pushServiceBlock(serviceNum, i, blockSize);
 
     if (blockSize > 0) {
-      i += blockSize - 1;
+      i += blockSize;
     }
   }
 };
@@ -548,16 +640,46 @@ Cea708Stream.prototype.push708Packet = function() {
  */
 Cea708Stream.prototype.pushServiceBlock = function(serviceNum, start, size) {
   var b;
+  var dw;
   var i = start;
   var packetData = this.current708Packet.data;
   var service = this.services[serviceNum];
 
+  debugger;
+
   if (!service) {
     service = this.initService(serviceNum, i);
   }
 
   for (; i < start + size && i < packetData.length; i++) {
     b = packetData[i];
+    let skip = 0;
+
+    // extended commands
+    if (b === 0x10) {
+      b = packetData[i++];
+      if (b <= 0x1f) {
+        console.log('cl group c2', dw.toString(16));
+      } else if (b >= 0x20 && b <= 0x7f) {
+        console.log('gl group g2', dw.toString(16));
+      } else if (b >= 0x80 && dw <= 0x9f) {
+        console.log('cr group c3', dw.toString(16));
+      } else if (dw >= 0xa0 && dw <= 0xff) {
+        console.log('gr group g3', dw.toString(16));
+      }
+    } else if (b <= 0x1f) {
+      skip = handleC0(b);
+    } else if (b <= 0x7f) {
+      skip = handleG0(b);
+    } else if (b <= 0x9f) {
+      skip = handleC1(b);
+    } else if (b <= 0xff) {
+      skip = handleG1(b);
+    }
+    if (skip) {
+      i += skip;
+    }
+    continue;
 
     if (within708TextBlock(b)) {
       i = this.handleText(i, service);

lib/tools/caption-packet-parser.js

@@ -122,6 +122,7 @@ var parseUserData = function(sei) {
 var parseCaptionPackets = function(pts, userData) {
   var results = [], i, count, offset, data;
 
+
   // if this is just filler, return immediately
   if (!(userData[0] & 0x40)) {
     return results;
@@ -142,6 +143,7 @@ var parseCaptionPackets = function(pts, userData) {
       results.push(data);
     }
   }
+
   return results;
 };