JVC manual Requirements for network using VN-E4,
2-1 Network Bandwidth, Input CH Frame Size

Preparation (continued)

2. Requirements for network using VN-E4

2-1 Network Bandwidth

Ensure that there is sufficient network bandwidth for the data volume to be transmitted by VN-E4.Data volume to be transmitted by VN-E4varies with the number of image or audio distributions.

●Data volume of images

VN-E4enables creation of up to 8 different types of images.

	Input CH	Frame Size
No. 1	CH1	VGA
No. 2	CH1	QVGA
No. 3	CH2	VGA
No. 4	CH2	QVGA
No. 5	CH3	VGA
No. 6	CH3	QVGA
No. 7	CH4	VGA
No. 8	CH4	QVGA

VN-E4allows distribution of each image to multiple destinations. Data of image to be transmitted by VN-E4is therefore the aggregate total of all these data.

Data volume of No. 1 L no. of distributions + data volume of No. 2 L no. of distributions +...+ data volume of No. 8 L no. of distributions

The number of distributions shall be the total number of stream transmissions via TCP (number of clients) and multicast. (Example)

Data volume will be calculated according to the formula below when 3 streams of No. 1 are sent. JPEG file size per frame L frame rate L 3

If the JPEG file size per frame is 30 KB and frame rate is 30 fps, then data volume will be as follows.

30 KB L 30 fps L 3 = 2700 KB/sec = Approx. 21 Mbps

The JPEG file size per frame varies with the parameter set as well as input video signals. The following table may be used as a reference.

Picture Quality Control Method		VGA File Size	QVGA File Size
	1 (High)	80 KB	27 KB
	2	60 KB	20 KB
	3	40 KB	13 KB
VFS (Variable File Size)
	4 (Medium)	30 KB	10 KB
	5	25 KB	8 KB
	6	20 KB	7 KB
	7 (Low)	15 KB	5 KB
		Selection may be made from the	Selection may be made from the
AFS (Average File Size)		range between 10 to 100 KB	range between 3 to 33 KB
CFS (Constant File Size)		Selection may be made from the	Selection may be made from the
		range between 10 to 100 KB	range between 3 to 33 KB

●Audio data volume

Audio data transmitted by VN-E4is at 64 kbps per stream. Audio data volume may be calculated using the following formula. 64 kbps L no. of streams

The number of streams is the total number of streams sent via TCP (number of clients), streams sent via multicast, and stream received by VN-E4.

(Example)

When VN-E4sends out 2 audio streams and receives 1 audio stream, data volume will be as follows. 64 kbps L 3 = 192 kbps

NOTE:

When there is insufficient network bandwidth, the number of JPEG frames (frame rate) that may be acquired by the client will decrease.

In addition, delay time will be prolonged and interruptions will also occur in the audio data.

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