Advanced Metadata Handling

Understanding Audio Metadata

AudioX provides comprehensive tools for reading, writing, and manipulating audio file metadata. This guide covers advanced metadata handling techniques and best practices.

Metadata Types

Standard Metadata Fields

interface AudioMetadata {
  title?: string
  artist?: string
  album?: string
  year?: string
  genre?: string
  track?: string
  composer?: string
  copyright?: string
  description?: string
}

Custom Metadata

// Adding custom metadata
await audio('input.mp3', 'output.mp3', {
  metadata: {
    custom_field: 'value',
    processing_date: new Date().toISOString(),
    source_quality: 'studio',
  }
})

Reading Metadata

Basic Metadata Reading

import { getAudioInfo } from '@stacksjs/audiox'

const info = await getAudioInfo('audio.mp3')
console.log(info.metadata) // Access standard metadata

Advanced Metadata Extraction

// Reading specific metadata tags
const info = await getAudioInfo('audio.mp3', {
  metadataTags: ['title', 'artist', 'custom_field']
})

Writing Metadata

Metadata Preservation

// Preserve existing metadata while converting
await audio('input.mp3', 'output.wav', {
  preserveMetadata: true,
  metadata: {
    // Add or override specific fields
    processing_tool: 'audiox',
  }
})

Batch Metadata Updates

// Update metadata for multiple files
async function updateBatchMetadata(files: string[], metadata: AudioMetadata) {
  for (const file of files) {
    await audio(file, file, {
      metadata,
      preserveExisting: true,
    })
  }
}

Metadata Manipulation

Metadata Transformation

// Transform metadata during processing
function transformMetadata(original: AudioMetadata): AudioMetadata {
  return {
    ...original,
    title: `${original.title} (Processed)`,
    processing_date: new Date().toISOString(),
  }
}

Metadata Validation

// Validate metadata before writing
function validateMetadata(metadata: AudioMetadata): boolean {
  const required = ['title', 'artist']
  return required.every(field => metadata[field]?.length > 0)
}

Best Practices

Metadata Handling

1. Always validate metadata before writing
2. Preserve important existing metadata
3. Use consistent naming conventions
4. Handle missing metadata gracefully

Performance Considerations

1. Batch metadata operations when possible
2. Cache metadata for frequently accessed files
3. Implement proper error handling
4. Use appropriate metadata field types

Advanced Use Cases

Automated Metadata Management

// Automatically manage metadata based on file content
async function autoMetadata(file: string) {
  const info = await getAudioInfo(file)

  return {
    title: generateTitle(info),
    artist: extractArtist(info),
    quality: determineQuality(info),
    processed_by: 'audiox',
    processing_date: new Date().toISOString(),
  }
}

Custom Metadata Schemas

// Implement custom metadata schemas
interface CustomAudioMetadata extends AudioMetadata {
  processing: {
    tool: string
    version: string
    date: string
    settings: Record<string, unknown>
  }
  quality: {
    original: string
    processed: string
    improvement: number
  }
}