Unibrain Fire-i 530/550/630/830/850 Operation Manual
Page 7
1.6.
Pixel Data
The Unibrain Fire-i ultra compact form Series complies with the IIDC 1394-Based Digital Camera Specification
V1.31 where data packets are transmitted by a FireWire
TM
interface as isochronous packets. Every video format,
mode and frame rate has a different video data format. (Pixel data source: IIDC V1.31 Specification)
Isochronous Data Block Packet Format
0 - 7
8 - 15
16 - 23
24 - 31
Data Length
tg
channel
tCode
Sy
Header CRC
Video data payload
Data CRC
Where the following fields are defined in the IEEE 1394 standard as:
Data length: number of bytes in the data field tg: (tag field) shall be set to zero
channel: isochronous channel number, as programmed in the iso_channel field of the cam_sta_ctrl register
tCode: (transaction code) shall be set to the isochronous data block packet tCode
sy: (synchronization value) shall be set to 0001h on the first isochronous data block of a frame, and shall be set to
zero on all other isochronous data blocks
Video data payload: shall contain the digital video information, as defined in the following sections
of the
Video data Payload Structure
Pn
:
Pixel number / packet
K
:
Pn x n (n = 0…..N-1)
(Pn x N = Total pixel number /frame)
<YUV (4: 2: 2) format >
U-(K+0)
Y-(K+0)
V-(K+0)
Y-(K+1)
U-(K+2)
Y-(K+2)
V-(K+2)
Y-(K+3)
U-(K+4)
Y-(K+4)
V-(K+4)
Y-(K+5)
U-(K+Pn-6)
Y-(K+Pn-6)
V-(K+Pn-6)
Y-(K+Pn-5)
U-(K+Pn-4)
Y-(K+Pn-4)
V-(K+Pn-4)
Y-(K+Pn-3)
U-(K+Pn-2)
Y-(K+Pn-2)
V-(K+Pn-2)
Y-(K+Pn-1)
<YUV (4: 1: 1) format >
U-(K+0)
Y-(K+0)
Y-(K+1)
V-(K+0)
Y-(K+2)
Y-(K+3)
U-(K+4)
Y-(K+4)
Y-(K+5)
V-(K+4)
V-(K+4)
Y-(K+5)
