API.md

mediainfo.js API

The main package export is a factory function that will handle instantiation and loading of the WASM module for you. It works asynchronous.

MediaInfoFactory(opts, successCallback, errorCallback)

Asynchronously create an instance of MediaInfo.

Defaults: opts = { chunkSize: 256*1024, coverData: false, format: 'object', full: false, ... }

• chunkSize: Chunk size used by analyzeData (in bytes)
• coverData: Whether to extract binary cover data (Base64-encoded)
• format: Format of result value (choices: object, JSON, XML, HTML or text)
• full: Full information display (all internal tags)
• Other Emscripten Module attributes
• Returns a Promise if no callback is given.

Example

const mediainfo = await MediaInfoFactory({ format: 'text' })

MediaInfo

MediaInfo.analyzeData(getSize, readChunk, cb)

Convenience method for analyzing a buffer chunk by chunk.

Media files can be several gigabytes in size. The preferred way is to load data in chunks to prevent memory exhaustion. analyzeData is a helper method that facilitates this somewhat cumbersome process.

You need to provide two functions.

• getSize: Return total buffer size
  (): Promise<number> | number
• readChunk: Read a data chunk of size with offset
(size: number, offset: number): Promise<Uint8Array> | Uint8Array

You can either provide a callback function that is called once the processing is done or the function will return a Promise.

Example

// Fake data (replace this with real file data)
const getSize = () => 100;
const readChunk = () => new Uint8Array(10);

const result = await mediainfo.analyzeFile(getSize, readChunk);

Low-level methods

The mediainfo object also exposes a number of low-level methods analogous to the MediaInfoLib buffer methods.

close(), inform(), openBufferContinue(data, size), openBufferContinueGotoGet(), openBufferFinalize(), openBufferInit(size, offset)