Appendix C: Bandwidth Calculation
The frame rate of video transmitted from the
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
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.
Not | Audio streaming also takes bandwidth around 32 kbps to |
64kbps. Most ADSL/Cable modem upload speeds may not | |
e | 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. |
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