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MT9T111_DG - Rev. B 9/10 EN
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MT9T111: Developer Guide
JPEG Encoder
Preliminary
Thumbnail Index Pointer
The thumbnail index pointer is the content to be stored in the thumbnail index table,
and every pointer consumes one entry in the table.
Note:
The index pointer is defined as the first data of every thumbnail line, which does not
account the SOEI. For example, if the first line of thumbnail data is placed at the
beginning of the outgoing data stream, the first thumbnail index pointer (P0) is
0x0002.
JPEG Status Segment
To provide the user quick knowledge of the status when the JPEG plus thumbnail is
enabled, a JPEG status segment is appended at the end of frame. This segment is
optional in continuous mode, while it is mandatory for spoof mode.The status segment
is enclosed by SOSI/EOSI codes, as shown in Figure 19.
Figure 19:
Contents of Status Segment
The contents of the status segment are summarized as follows:
• SOSI, start of status information, which is coded as 0xFFBC
• Thumbnail index table (every entry has 4 bytes) is asserted and thumbnail is enabled
• The width of thumbnail in pixels (2 bytes)
• The height of thumbnail (2 bytes)
• The width of uncompressed full image
• The height of uncompressed full image
• 4-byte JPEG plus thumbnail length
• 2-byte status
• EOSI, end of status information, which is coded as 0xFFBD
Either thumbnail data or JPEG data starts first, depending on the time of their avail-
ability.
SOSI
(0xFFBC)
EOSI
(0xFFBD)
Thumbnail
Index Table
(optional)
Thumbnail Size
(optional)
Original
JPEG Size
(optional)
TXF
Status
(2 bytes)
Frame
Length
(4 bytes)