Inhaltsverzeichnis

4CC Binary Blob Format
- Constraints
- Example
  - Efficiency
Directory Extension
- Example

4CC Binary Blob Format

Header:
- 4CC: 4 byte character code
- bytelength: 4 byte unsigned payload size in bytes
Payload:
- data: payload data max 2^32 bytes

Constraints

Only write whole structure
- There will be no case in which a partial 4CC binary blob will be rewritten

Example

'_' specifies whitespace (0x20)

Header		Payload
4CC	bytelength	data
4	4	n/a
'__ID'	0x3	'DIA'
'_REV'	0x1	0xa
'_SER'	0xa	'6502400001'

Efficiency

Payload: 14 bytes
Overhead: 24 bytes
→ 37%

Directory Extension

First bit (MSB) of first byte of 4CC field is directory extension bit
If set data field will start with another header

Example

4CC = '_SER' = 0x20534552
4CC* = 0xa0534552
4CC*: 4 byte character code field with directory extension bit set

Header		Payload
		Header		Payload
4CC*	bytelength	4CC	bytelength	data