JFIF Extension (JFXX) Segment Format
An optional second application segment allows a thumbnail image to be embedded using several different image formats (to save space).
Field | Size (bytes) | Description | |||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
APP0 marker | 2 | Always equals 0xFFE0 | |||||||||||||||||||||||||||
Length | 2 | Length of segment excluding APP0 marker | |||||||||||||||||||||||||||
Identifier | 5 | Always equals "JFXX" (with zero following) (0x4A46585800) | |||||||||||||||||||||||||||
Thumbnail format | 1 | Specifies what data format is used for the thumbnail:
|
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Thumbnail data | Variable |
JPEG
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Read more about this topic: JPEG File Interchange Format, File Format Structure
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