JVC VN-V685U - Manual (Page 14)

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2.5. MPEG-4 Stream Format Sent Out by VN-V685/686/686B
MPEG-4 stream from VN-V685/686/686B is MPEG-4 Part 2(ISO/IEC 14496-2) compliant, level 3 of simple profile. It
is a sequence of I-VOPs, or I-VOPs and P-VOPs.
I-VOP: Intra frame compressed data
P-VOP: Inter frame compressed data with previous frame
Ratio of I-VOP and P-VOP depends on I-Frame interval setting. Encode page of Web has the setting.
First VOP can be I-VOP or P-VOP. If client want to decode from I-VOP, please skip P-VOP and wait first I-VOP.
Example of MPEG-4 stream
There are VOL, Userdata1, GOV and Userdata2 before each I-VOP. In VN-V686 before v1.02, "Intelligent tarcking
status" of Userdata2 is not available.
Data Structure before I-VOP
Item Note
VOL VOL of MPEG-4 Video
Userdata1 Reserved
GOV GOV of MPEG-4 Video
Userdata2 Userdata
Data Structure of Userdata2
Item Example Note
Start Code 0x000001B2 Start code of userdata in MPEG-4 Video
Product Name type = VN-V685U Product Name
Timestamp Timestamp =
20070319161455123UTC
Year, Month, Day, Hour, Minute, Second,
Millisedond, and Time zone
Camera ID camera = Camera01 Camera ID that user can define
HTTP Response
P-VOP
P-VOP
I-VOP
P-VOP
VOL
P-VOP