libaaruformat/docs/spec/blocks/metadata.adoc

=== Metadata Block (`META`)

The metadata block contains descriptive information related to the media source, which is not part of the original media data itself.
Typical fields may include the manufacturer name, device model, acquisition sequence identifiers, and other contextual attributes.

All string values within this block are encoded as little-endian UTF-16 and terminated with a null character.

[source,c]
#define META_MAGIC 0x4154454D
/**Metadata block, contains metadata */
typedef struct MetadataBlockHeader
{
    /**Identifier, <see cref="BlockType.MetadataBlock" /> */
    uint32_t identifier;
    /**Size in uint8_ts of this whole metadata block */
    uint32_t blockSize;
    /**Sequence of media set this media beint64_ts to */
    int32_t  mediaSequence;
    /**Total number of media on the media set this media beint64_ts to */
    int32_t  lastMediaSequence;
    /**Offset to start of creator string from start of this block */
    uint32_t creatorOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t creatorLength;
    /**Offset to start of creator string from start of this block */
    uint32_t commentsOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t commentsLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaTitleOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaTitleLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaManufacturerOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaManufacturerLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaModelOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaModelLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaSerialNumberOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaSerialNumberLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaBarcodeOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaBarcodeLength;
    /**Offset to start of creator string from start of this block */
    uint32_t mediaPartNumberOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t mediaPartNumberLength;
    /**Offset to start of creator string from start of this block */
    uint32_t driveManufacturerOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t driveManufacturerLength;
    /**Offset to start of creator string from start of this block */
    uint32_t driveModelOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t driveModelLength;
    /**Offset to start of creator string from start of this block */
    uint32_t driveSerialNumberOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t driveSerialNumberLength;
    /**Offset to start of creator string from start of this block */
    uint32_t driveFirmwareRevisionOffset;
    /**Length in uint8_ts of the null-terminated UTF-16LE creator string */
    uint32_t driveFirmwareRevisionLength;
} MetadataBlockHeader;

==== Field Descriptions

[cols="2,2,2,6",options="header"]
|===
|Type
|Size
|Name
|Description

|uint32_t
|4 bytes
|identifier
|The metadata table identifier, always `META`

|uint32_t
|4 bytes
|blockSize
|The size of this block including all of its data.

|int32_t
|4 bytes
|mediaSequence
|The number of heads.

|int32_t
|4 bytes
|lastMediaSequence
|The number of sectors per track.

|uint32_t
|4 bytes
|creatorOffset
|Offset to start of creator string from start of this block.

|uint32_t
|4 bytes
|creatorLength
|Length in bytes of the creator string.

|uint32_t
|4 bytes
|commentsOffset
|Offset to start of comments string from start of this block.

|uint32_t
|4 bytes
|commentsLength
|Length in bytes of the comments string.

|uint32_t
|4 bytes
|mediaTitleOffset
|Offset to start of media title string from start of this block.

|uint32_t
|4 bytes
|mediaTitleLength
|Length in bytes of the media title string.

|uint32_t
|4 bytes
|mediaManufacturerOffset
|Offset to start of media manufacturer string from start of this block.

|uint32_t
|4 bytes
|mediaManufacturerLength
|Length in bytes of the media manufacturer string.

|uint32_t
|4 bytes
|mediaModelOffset
|Offset to start of media model string from start of this block.

|uint32_t
|4 bytes
|mediaModelLength
|Length in bytes of the media model string.

|uint32_t
|4 bytes
|mediaSerialNumberOffset
|Offset to start of media serial number string from start of this block.

|uint32_t
|4 bytes
|mediaSerialNumberLength
|Length in bytes of the media serial number string.

|uint32_t
|4 bytes
|mediaBarcodeOffset
|Offset to start of media barcode string from start of this block.

|uint32_t
|4 bytes
|mediaBarcodeLength
|Length in bytes of the media barcode string.

|uint32_t
|4 bytes
|mediaPartNumberOffset
|Offset to start of media part number string from start of this block.

|uint32_t
|4 bytes
|mediaPartNumberLength
|Length in bytes of the media part number string.

|uint32_t
|4 bytes
|driveManufacturerOffset
|Offset to start of drive manufacturer string from start of this block.

|uint32_t
|4 bytes
|driveManufacturerLength
|Length in bytes of the drive manufacturer string.

|uint32_t
|4 bytes
|driveModelOffset
|Offset to start of drive model string from start of this block.

|uint32_t
|4 bytes
|driveModelLength
|Length in bytes of the drive model string.

|uint32_t
|4 bytes
|driveSerialNumberOffset
|Offset to start of drive serial number string from start of this block.

|uint32_t
|4 bytes
|driveSerialNumberLength
|Length in bytes of the drive serial number string.

|uint32_t
|4 bytes
|driveFirmwareRevisionOffset
|Offset to start of drive firmware revision string from start of this block.

|uint32_t
|4 bytes
|driveFirmwareRevisionLength
|Length in bytes of the drive firmware revision string.
|===