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DCS-6620G User’s Manual

D-Link Systems, Inc.

Using the DCS-6620G with an Internet Browser

Click the

Video

button from the Configuration screen to access video settings that affect how

the video image appears.

Configuration > Advanced > Video

Select either for color or monochrome video display

Size:

Color:

Click

Video

Three options exist for the sizes of the video display. You can

select between

176x120/176x144

,

352x240/352x288

, or

704x480/

401x576

. The first value represents the PAL format of video and

the second value represents the NTSC format. In

704x480/401x576

mode, the frame rate will be reduced to 10fps and increased to

30fps automatically when it is switched back to a lower image

size.

Maximum frame rate:

This limits the maximal refresh frame rate, which can be combined

with the “

Video quality control

” to optimize the bandwidth utilization

and video quality. If the User wants to fix the bandwidth utilization

regardless of the video quality, choose “

Fix bit rate

” and select

the desired bandwidth.

Video codec type:

It can be either MJPEG or MPEG4. In MJPEG mode, the video

frames are independent. In MPEG4 mode, there are I frames and

P frames. To decode a P frame need the information of previous

frame. MPEG4 consumes much less network bandwidth than

MJPEG.

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DCS-6620G User’s Manual

D-Link Systems, Inc.

Using the DCS-6620G with an Internet Browser

Configuration > Advanced > Video

(continued)

Key frame interval:

Video quality control:

Vertically rotate the video.

A large “

Key frame interval

” value can reduce the bit rate, but if

there is a packet loss during transmission, it will cause image

corruption. “

Fix bit rate

” and “

Key frame interval

” are only available in

“

MPEG4

” mode. The video quality may be poor due to the sending

of maximal frame rate within the limited bandwidth, which is when

images are moving rapidly. Consequently, to ensure detailed

video quality (quantization rate) regardless of the network, it will

utilize more bandwidth to send the maximal frames when images

change drastically.

To fix the bandwidth utilization regardless of the video quality,

choose

Fix bit rate

and select

the desired bandwidth. The video

quality may be reduced in order to send maximum frames with

limited bandwidth, especially when images change drastically.

For higher video detail regardless of the bandwidth selection,

select

Fix quality

and select a video quality level. This setting will

utilize more bandwidth to send the maximum frames when images

change drastically.

Horizontally rotate the video. Check options both if the Network

Camera is installed upside down.

Click

Apply

to make

changes effective

Flip:

Mirror:

Improve efficiancy

in the multi-user

environment

:

Check this option to improve efficiency in the multi-user environment

when running in the low bandwidth environment.

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DCS-6620G User’s Manual

D-Link Systems, Inc.

Using the DCS-6620G with an Internet Browser

Click the

Audio/Video

button from the Configuration screen to access video settings that affect

how the video image appears.

Configuration > Advanced > Audio

Click

Audio

There are five options to select. For all the modes, only one client

can talk to the server at the same time.

In this mode, the User can talk to the server while listening sound

from the server simultaneously.

In this mode, the User can talk to the server or listen from the

server, but not at the same time.

In this mode, the User can only talk to the server.

In this mode, the User can only listen from the server.

In this mode, the audio is disabled in both directions.

Transmission Mode:

Full Duplex

(Talk and listen

Simultaneously):

Half Duplex

(Talk or listen, not at the

same time):

Simplex- Talk only:

Simplex- Listen only:

Disable:

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DCS-6620G User’s Manual

D-Link Systems, Inc.

Using the DCS-6620G with an Internet Browser

Recommendations for setting video for the best performance:

“Best performance” means the image refresh rate should be the fastest possible and the video

quality should be the best possible at the lowest network bandwidth possible. Three factors,

Maximum frame rate

,

Fix bit rate

, and

Fix quality

in the

Video Configuration

page, are related to

performance.

Recording settings for real-time motion images

To achieve a real-time visual effect, the network bandwidth should be large enough to transmit

20 image frames per second (fps) or more. If you are on a broadband network over 1Mbps,

you can set

Fix bit Rate

to 1000Kbps or 1200Kbps, or set

Fix quality

to achieve the maximum

frames. The maximum frame rate is 25 in 50Hz system and 30 in 60Hz system. If your network

bandwidth is more than 384Kbps, you can adjust

Fix bit rate

according to your bandwidth and

set the maximum frame rate of 25 to 30.

If the images vary dramatically in your environment, you may slow down the maximum frame

rate to 20 to decrease the transmitted data for better video quality. Since the human eye

could not easily differentiate between 20 and 25 or 30 frames per second, the slower frame

rate will not be noticed. If your network bandwidth is below 384 Kbps, you should adjust the

bit rate according to your bandwidth and experiment to allow for the best frame rate that can

be achieved. The faster frame rate in a slow network will blur the images. You may also try to

choose

352x240/352x288

in size option for better images or

704x480/704x576

for larger image

size. Because the network has burst constraints and everyone’s environment is not the same,

any poor connection will impair normal performance.

Send audio from the

active client to all the

other clients:

Improve audio quality

in low bandwidth

environment:

Audio source:

Acoustic echo

cancellation:

Bit rate:

Configuration > Advanced > Audio

(continued)

In half duplex transmission mode, select the option to talk to the

server and broadcast your voice to all the other clients.

If the Network Camera works in versatile or low network bandwidth

environment, the User can check this option to improving audio

quality by sacrificing some real-time synchronization.

Select source from external or built-in microphone.

If the Network Camera works in versatile or low network bandwidth

environment, the User can check this option to improving audio

quality by sacrificing some real-time synchronization.

There are three kinds of bit-rate for audio. 32Kbps and 24Kbps

are suitable for both music and speech like audio while 8Kbps

are suitable for only speech like audio.

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DCS-6620G User’s Manual

D-Link Systems, Inc.

Using the DCS-6620G with an Internet Browser

Recording settings to compromise between real-time and clear images

If you have a broadband network, set

Fix quality

to

Good

image quality, or higher,

instead of

setting the

Bit rate

. Otherwise, fix the bit rate according to your actual network speed and set

the frame rate to 30. If the image quality is low, select a lower frame rate above 15. If the image

quality is still not improved, select a lower bit rate.

Recommendations for setting video for the best performance

(continued)

:

Click the Image Setting button from the Configuration screen to access additional settings that

affect how the video image appears.

Configuration > Advanced > Image Setting

Click

Image Setting