package funkin.audio.waveform; import funkin.util.TimerUtil; class WaveformDataParser { static final INT16_MAX:Int = 32767; static final INT16_MIN:Int = -32768; static final INT8_MAX:Int = 127; static final INT8_MIN:Int = -128; public static function interpretFlxSound(sound:flixel.sound.FlxSound):Null { if (sound == null) return null; // Method 1. This only works if the sound has been played before. @:privateAccess var soundBuffer:Null = sound?._channel?.__source?.buffer; if (soundBuffer == null) { // Method 2. This works if the sound has not been played before. @:privateAccess soundBuffer = sound?._sound?.__buffer; if (soundBuffer == null) { trace('[WAVEFORM] Failed to interpret FlxSound: ${sound}'); return null; } else { // trace('[WAVEFORM] Method 2 worked.'); } } else { // trace('[WAVEFORM] Method 1 worked.'); } return interpretAudioBuffer(soundBuffer); } public static function interpretAudioBuffer(soundBuffer:lime.media.AudioBuffer):Null { var sampleRate = soundBuffer.sampleRate; var channels = soundBuffer.channels; var bitsPerSample = soundBuffer.bitsPerSample; var samplesPerPoint:Int = 256; // I don't think we need to configure this. var pointsPerSecond:Float = sampleRate / samplesPerPoint; // 172 samples per second for most songs is plenty precise while still being performant.. // TODO: Make this work better on HTML5. var soundData:lime.utils.Int16Array = cast soundBuffer.data; var soundDataRawLength:Int = soundData.length; var soundDataSampleCount:Int = Std.int(Math.ceil(soundDataRawLength / channels / (bitsPerSample == 16 ? 2 : 1))); var outputPointCount:Int = Std.int(Math.ceil(soundDataSampleCount / samplesPerPoint)); // trace('Interpreting audio buffer:'); // trace(' sampleRate: ${sampleRate}'); // trace(' channels: ${channels}'); // trace(' bitsPerSample: ${bitsPerSample}'); // trace(' samplesPerPoint: ${samplesPerPoint}'); // trace(' pointsPerSecond: ${pointsPerSecond}'); // trace(' soundDataRawLength: ${soundDataRawLength}'); // trace(' soundDataSampleCount: ${soundDataSampleCount}'); // trace(' soundDataRawLength/4: ${soundDataRawLength / 4}'); // trace(' outputPointCount: ${outputPointCount}'); var minSampleValue:Int = bitsPerSample == 16 ? INT16_MIN : INT8_MIN; var maxSampleValue:Int = bitsPerSample == 16 ? INT16_MAX : INT8_MAX; var outputData:Array = []; var perfStart:Float = TimerUtil.start(); for (pointIndex in 0...outputPointCount) { // minChannel1, maxChannel1, minChannel2, maxChannel2, ... var values:Array = []; for (i in 0...channels) { values.push(bitsPerSample == 16 ? INT16_MAX : INT8_MAX); values.push(bitsPerSample == 16 ? INT16_MIN : INT8_MIN); } var rangeStart = pointIndex * samplesPerPoint; var rangeEnd = rangeStart + samplesPerPoint; if (rangeEnd > soundDataSampleCount) rangeEnd = soundDataSampleCount; for (sampleIndex in rangeStart...rangeEnd) { for (channelIndex in 0...channels) { var sampleIndex:Int = sampleIndex * channels + channelIndex; var sampleValue = soundData[sampleIndex]; if (sampleValue < values[channelIndex * 2]) values[(channelIndex * 2)] = sampleValue; if (sampleValue > values[channelIndex * 2 + 1]) values[(channelIndex * 2) + 1] = sampleValue; } } // We now have the min and max values for the range. for (value in values) outputData.push(value); } var outputDataLength:Int = Std.int(outputData.length / channels / 2); var result = new WaveformData(null, channels, sampleRate, samplesPerPoint, bitsPerSample, outputPointCount, outputData); trace('[WAVEFORM] Interpreted audio buffer in ${TimerUtil.seconds(perfStart)}.'); return result; } public static function parseWaveformData(path:String):Null { var rawJson:String = openfl.Assets.getText(path).trim(); return parseWaveformDataString(rawJson, path); } public static function parseWaveformDataString(contents:String, ?fileName:String):Null { var parser = new json2object.JsonParser(); parser.ignoreUnknownVariables = false; trace('[WAVEFORM] Parsing waveform data: ${contents}'); parser.fromJson(contents, fileName); if (parser.errors.length > 0) { printErrors(parser.errors, fileName); return null; } return parser.value; } static function printErrors(errors:Array, id:String = ''):Void { trace('[WAVEFORM] Failed to parse waveform data: ${id}'); for (error in errors) funkin.data.DataError.printError(error); } }