tav-media/lib/src/wasm/audio-worklet/movie-audio-processor.d.ts

Cross platform media editing framework

export const movieAudioProcessorCode: "class MovieAudioProcessor extends AudioWorkletProcessor {\n  static get parameterDescriptors() {\n    return [\n      { name: 'bitDepth', defaultValue: 16, minValue: 1, maxValue: 32 },\n    ];\n  }\n\n  constructor() {\n    super();\n    this.bitDepth_ = 16;\n    this.paused = false;\n    this.inputIndexes = [];\n    this.port.onmessage = (e) => {\n      const { operation, index } = e.data;\n      if (operation === 'pause') {\n        this.paused = true;\n      } else if (operation === 'play') {\n        this.paused = false;\n      } else if (operation === 'connect') {\n        this.inputIndexes.push(index);\n      } else if (operation === 'disconnect') {\n        this.inputIndexes.splice(this.inputIndexes.indexOf(index), 1);\n      }\n    }\n  }\n\n  handleMessage() {\n    this.port.postMessage('received');\n  }\n\n  process(inputs, outputs, parameters) {\n    if (this.paused) return true;\n    if (inputs.length === 0) {\n      return true;\n    }\n\n    const { bitDepth } = parameters;\n    const factor = 2 ** (bitDepth - 1);\n    const range = 25000;\n\n    const outBuffers = [];\n    const outDataList = {};\n    for (const inputIndex of this.inputIndexes) {\n      const input = inputs[inputIndex];\n      if (!input || input.length === 0) {\n        continue;\n      };\n      const sampleCount = input[0].length;\n      const outData = [];\n      for (let channel = 0; channel < input.length; ++channel) {\n        for (let dataIndex = 0; dataIndex < input[channel].length; dataIndex++) {\n          let transformedValue = Math.floor(input[channel][dataIndex] * factor + 0.5);\n          if (transformedValue >= range ) {\n            transformedValue = range;\n          } else\n            if (transformedValue <= -range) {\n              transformedValue = -range;\n            }\n          outData[input.length * dataIndex + channel] = transformedValue;\n        }\n      }\n      const arrayBuffer = new Int16Array(outData);\n      outDataList[inputIndex] = {\n        bytes: arrayBuffer.buffer,\n        sampleCount,\n        channelCount: input.length,\n      };\n      outBuffers.push(arrayBuffer.buffer);\n    }\n\n    this.port.postMessage({\n      outDataList\n    }, outBuffers);\n\n    return true;\n  }\n}\nregisterProcessor('movie-audio-processor', MovieAudioProcessor);";