Audio syncing

[Fistarn1]

I would love to see a feature where you could change the audio offset. I noticed some of the songs I converted has gotten out of sync. The same songs are not out of sync inside of Rocksmith.

On another note. I love your work and have been using Chartplayer a ton lately. So thanks a ton for taking the time to make it!!

[mikeoliphant]

If the songs play correctly in Rocksmith, that sounds like a issue that should be fixed in some other way.

Can you give me some examples of songs that are out of sync?

[Fistarn1]

Tenacious D - Beelzeboss and Guns N Roses - Sweet Child O' Mine was out of sync in Chartplayer but not in Rocksmith. I did however manage to sync it myself. I can write the script I used to sync it here. (note that I do not know how to code at all and this was all done by AI)

So it works by renaming the out of sync lead.json file to tab-data.json and setting "const TIME_SHIFT = 2.0;" to however many second or -seconds it is out of sync. Then running the script with node and it will output a file called backward-shifted-tab.json that you just have to rename to lead.json and replace the old out of sync one with.

Just save the code as .js and run it with node i guess.

// Function to shift all time values by a specified amount
function shiftTimeValues(data, timeShift) {
// Create a deep copy of the data to avoid modifying the original
const shiftedData = JSON.parse(JSON.stringify(data));

// Shift section times
shiftedData.Sections.forEach(section => {
if (section.EndTime !== undefined) {
section.EndTime += timeShift; // Adding negative value = subtraction
}
if (section.StartTime !== undefined) {
section.StartTime += timeShift; // Adding negative value = subtraction

  // Ensure we don't have negative start times
  if (section.StartTime < 0) {
    section.StartTime = 0;
  }
}

});

// Shift note times
shiftedData.Notes.forEach(note => {
if (note.TimeOffset !== undefined) {
note.TimeOffset += timeShift; // Adding negative value = subtraction

  // Ensure we don't have negative time offsets
  if (note.TimeOffset < 0) {
    note.TimeOffset = 0;
  }
}

// If there are CentsOffsets (for bends), shift those times too
if (note.CentsOffsets) {
  note.CentsOffsets.forEach(offset => {
    if (offset.TimeOffset !== undefined) {
      offset.TimeOffset += timeShift; // Adding negative value = subtraction
      
      // Ensure we don't have negative time offsets
      if (offset.TimeOffset < 0) {
        offset.TimeOffset = 0;
      }
    }
  });
}

});

return shiftedData;
}

// Main function to process the file
function processTabFile(inputData, timeShift) {
try {
// Parse the JSON data
const tabData = inputData;

// Apply the time shift
const shiftedData = shiftTimeValues(tabData, timeShift);

// Return the shifted data
return {
  success: true,
  data: shiftedData,
  stats: {
    sections: shiftedData.Sections.length,
    notes: shiftedData.Notes.length,
    timeShift: timeShift
  }
};

} catch (error) {
return {
success: false,
error: error.message
};
}
}

// The time shift amount in seconds (negative for backward shift)
const TIME_SHIFT = 2.0;

// Read the JSON data from file
const fs = require('fs');
const inputData = JSON.parse(fs.readFileSync('tab-data.json', 'utf8'));

// Process the file
const result = processTabFile(inputData, TIME_SHIFT);

if (result.success) {
console.log(✅ Successfully shifted all timing data by ${TIME_SHIFT} seconds (backward).);
console.log( Processed ${result.stats.sections} sections and ${result.stats.notes} notes.);

// Show some examples of the shift
const originalFirstSection = inputData.Sections[0];
const shiftedFirstSection = result.data.Sections[0];
console.log(\nExample: Section "${originalFirstSection.Name}" end time shifted from ${originalFirstSection.EndTime} to ${shiftedFirstSection.EndTime});

if (inputData.Notes.length > 0) {
const originalFirstNote = inputData.Notes[0];
const shiftedFirstNote = result.data.Notes[0];
console.log(Example: First note time shifted from ${originalFirstNote.TimeOffset} to ${shiftedFirstNote.TimeOffset});
}

// Show a note that would be affected by the "no negative times" protection
if (inputData.Notes.some(note => note.TimeOffset < Math.abs(TIME_SHIFT))) {
console.log("\nNote: Some time values were clamped to 0 to prevent negative times.");
}

// Show some examples of the shifted data
console.log("\nSample of shifted section data:");
console.log(JSON.stringify(result.data.Sections.slice(0, 3), null, 2));

console.log("\nSample of shifted note data:");
console.log(JSON.stringify(result.data.Notes.slice(0, 2), null, 2));

// In a real implementation, you would write the result to a file
fs.writeFileSync('backward-shifted-tab.json', JSON.stringify(result.data, null, 2));
console.log("\nThe backward-shifted data is ready for use in your guitar tablature software.");
} else {
console.error(❌ Error processing file: ${result.error});
}

[mikeoliphant]

Was there a particular version of "Sweet Child" that you had trouble with?

I tried this one:

https://ignition4.customsforge.com/cdlc/517

and the sync seemed fine.