Myriad Metadata Import Documentation

Overview

When importing an audio file into the MediaWall, Myriad Playout v6 attempts to reads metadata from various audio file formats and populate the Media Item with the extracted information. This document describes the complete metadata extraction process, supported formats, and the specific tag field mappings that users can utilize when preparing audio files for import into Myriad.

The metadata import process operates in multiple phases, extracting information from different sources within the audio files, including standard ID3/tag data, broadcast-specific chunks, and embedded timing information.

Supported File Formats

Primary Audio Formats

• WAV - Full metadata support including CART, BEXT, and SCOT chunks
• MP3 - ID3v1, ID3v2 tag support and APE tag extensions
• FLAC - Comprehensive Vorbis comment metadata support
• OGG - Vorbis comment metadata
• OPUS - Custom metadata tag support with XML embedding
• MP2 - Basic tag metadata support
• AAC/M4A - iTunes-style metadata support

Special File Types

• SS32 Rotator Files - Scott Studios playlist/rotator files
• RadioHost Files - Files with embedded cue point data
• Media Foundation Compatible - Windows Media Foundation supported formats for less common audio formats

Metadata Extraction Process

The process follows a hierarchical approach to metadata extraction:

1. File Format Detection - Determines audio format from file extension
2. Audio Properties - Extracts duration, sample rate, and audio format
3. Primary Metadata - Standard tag information (TagLib)
4. Extended Metadata - Format-specific chunks and extensions
5. Timing Information - Broadcast cues, markers, and timing data
6. Adjacent Files - Companion metadata files

Standard Tag Field Mappings

The following table shows which specific tag fields are read from audio files and how they map to MediaItem properties:

ID3v1/ID3v2 Tags (MP3)

Vorbis Comments (FLAC/OGG)

iTunes/MP4 Tags (AAC/M4A)

Embedded Artwork

Extended Metadata Sources

APE Tags (Advanced Audio Coding)

APE tags provide broadcast-specific timing and metadata information primarily used by professional radio automation systems:

WAV File Chunks

CART Chunk (Broadcast Wave)

Professional broadcast metadata chunk containing comprehensive information:

PostTimer Mappings (CART Chunk)

BEXT Chunk (Broadcast Extension)

Basic broadcast metadata:

SCOT Chunk (Scott Studios)

Legacy format support for Scott Studios systems:

RadioHost File Support

Specialized cue point data for RadioHost systems:

OPUS Format Extensions

OPUS files support embedded XML metadata:

Special File Types

SS32 Rotator Files

Scott Studios playlist files are automatically detected and converted:

• Detection Method: SCOT chunk with rotator bit flags
• Content Type: Automatically changed to MediaListRotate
• Related Items: Playlist members extracted from data chunk
• Description: Automatically set to " SS32 Rotator "
• Processing: Audio data marked as invalid, metadata-only import

Metadata Processing Rules

String Sanitization

All text fields undergo sanitisation:

• Encoding normalization to handle international characters
• Null and empty string handling

Priority Handling

When multiple sources provide the same information (highest to lowest priority):

1. XML Files - Complete MediaItem XML overrides everything - see this article for more information.
2. CART Chunk - Professional broadcast metadata
3. APE Tags - Broadcast timing and extended metadata
4. Standard Tags - ID3, Vorbis, iTunes metadata
5. BEXT/SCOT Chunks - Legacy broadcast formats
6. Adjacent Files - BCX, CSV companion files - see this article for more information.
7. Filename Parsing - Last resort extraction from filename

Error Handling

• Individual metadata extraction errors don't fail the entire process
• Malformed tags are logged but don't prevent import
• Missing companion files are handled gracefully
• Invalid timing data is constrained to valid ranges

Content Validation

• Timing markers are validated against audio duration
• ISRC codes are format-validated
• Date fields are parsed with error tolerance
• Embedded images are validated for supported formats

Processing Examples

Standard MP3 File with ID3v2Input: song.mp3

ID3v2 Tags Found:

• TIT2 (Title): "Example Song"
• TPE1 (Artist): "Example Artist"
• TALB (Album): "Example Album"
• TDRC (Year): "2023"
• TCON (Genre): "Rock"
• TSRC (ISRC): "US1234567890"
• APIC: Embedded JPEG image

Result: SimpleMetadata MediaItem Properties:

• ItemTitle = "Example Song"
• Artists[0] = ArtistInfo(0, "Example Artist")
• AlbumTitle = "Example Album"
• FirstReleaseYear = 2023
• IngestCategoryName = "Rock"
• Copyright.ISRC = "US1234567890"
• TemporaryImageFiles[0] = "temp_image.jpg"

  WAV File with CART ChunkInput: broadcast.wav

  CART Chunk Data:
• Title: "News Bulletin"
• Artist: "News Team"
• Category: "News"
• PostTimer[0]: AUDs = 12000 samples (0.5s at 24kHz)
• PostTimer[1]: SEG1 = 600000 samples (25.0s at 24kHz)
• UserDef: "BackColor=&HFF0000&"
• TagText: "Breaking News"

Result: AdvancedMetadata
MediaItem Properties:

• ItemTitle = "News Bulletin"
• Artists[0] = ArtistInfo(0, "News Team")
• ItemDescription = "Breaking News"
• MediaLength.Start = 00:00:00.500
• Extro.Start = 00:00:25.000
• BackColor = Red
• UseCustomColors = True

  FLAC File with Vorbis Comments + BCXInput: track.flac + track.bcx

  Vorbis Comments:
• TITLE: "Classical Piece"
• ARTIST: "Orchestra"
• COMPOSER: "Famous Composer"
• MUSICBRAINZ_TRACKID: "abc-123-def"

BCX File Content:

• Auto Start Point: 1500 (1.5 seconds)
• Intro: 15000 (15 seconds)
• Auto Out Point: 180000 (3 minutes)

Result: SimpleMetadata (upgraded from BCX) MediaItem Properties:

• ItemTitle = "Classical Piece"
• Artists[0] = ArtistInfo(0, "Orchestra")
• Copyright.Composer = "Famous Composer"
• MusicBrainzId = "abc-123-def"
• MediaLength.Start = 00:00:01.500
• Intro.End = 00:00:15.000
• Extro.Start = 00:03:00.000

  File Preparation Guidelines