JVC VN-V686U manual 20070319161455123UTC

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

HTTP Response

P-VOP

P-VOP

P-VOP

VOL

I-VOP

P-VOP

There are VOL, Userdata1, GOV and Userdata2 before each I-VOP.

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-V686	Product Name
Timestamp	Timestamp =	Year, Month, Day, Hour, Minute, Second,
	20070319161455123UTC	Millisedond, and Time zone
Camera ID	camera = Camera01	Camera ID that user can define
Preset Position	position = 0	Indicates preset position number after moving to
Number		preset position. In other cases, position = NA.
Fan status	fan = 0	Indicates status of fan. 1 means error.

13