Planet ICA-500, Руководство пользователя

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ICA-500 User ’ s Manual
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Appendix E: Bandwidth
Estimation
The frame rate of video transmitted from the ICA-500 depends on connection bandwidth
between client and server and quality setting of server. Here is a guideline to help you
roughly estimate the bandwidth requirements form your ICA-500.
Image bandwidth is approximately equal to the average frame rate in frames per second
multiplied by the average frame data size in kilobits. Frame data size, or the number of
bits comprising a single video frame varies a great deal from depending on scene
complexity, lighting conditions, camera noise, etc. The table shown below is reference
figures. Actual results generated by the ICA-500 may be varying.
Image Resolution Average range of Data Sizes
176 x 144 (QCIF) 20 – 40k bit
320 x 240 (QVGA) 56 – 92k bit
352 x 288 (CIF) 64 – 112k bit
640 x 480 (VGA) 160 – 320k bit
For example, streaming 2 fps of 320 x 240 video requires 112 to 184 kbps (kilobits per
second). Therefore, with a 128K upload connection; you will typically see 3 to 6 frames
per second with 176 x 144 resolution and 1 to 2 frames per second with 320 x 240
resolution without audio stream.
Note:
Audio streaming also takes bandwidth around 32 kbps to 64kbps.
Most ADSL/Cable modem upload speeds may not even reach up to 128
kbps. Thus, you may not be able to receive any video while streaming audio
on a 128 kbps or lower connection. Even though the upload speed is more
than 128kbps, for optimal video performance, disabling audio streaming will
get better video performance.