# Bit rate

Discussion in 'Computing and Networks' started by Lightfire, Jan 23, 2012.

1. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
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Source: Wikipedia

What does this mean.

How to determine/know the number of bits of a certain video??

Thnx

zumiao likes this.
2. ### thatoneguy AAC Fanatic!

Feb 19, 2009
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For video, think of the data rate required for a low resolution, say, 800x600 pixels. Each pixel has 3 color values, so you end up with 24 bits per pixel.

If the display is refreshed 60 times per second, how many bits per second does the video card need to transmit to the display?

How much more data is needed to be transferred when displaying 1720x1080 at 30 frames per second?

Calculate that out and you'll see why HDTV can't be effectively broadcast with the old analog standards.

3. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
691,200,000 bits per second or 86,400,000 bytes per second?

So I need at least 86.4 megabytes per second internet connection? I can't afford that.

Am i right anyway?

thnx

4. ### MrChips Moderator

Oct 2, 2009
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That is why video data is compressed.

5. ### thatoneguy AAC Fanatic!

Feb 19, 2009
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Yes, that's why HDTV is 100% incompatible with the older TVs and analog broadcast methods.

Now the data is converted to digital, where it can be rather highly compressed, with some loss of quality, but sent over a much smaller bandwidth connection, be it radio waves, cable TV, or Internet.

6. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
Thnx MrChips and thatoneguy.
I looked up the details of my recorded video and here what I saw.

Length: 00:02:43
Frame width: 640
Frame height: 480
Data Rate: 12,544kbps
Total bit rate: 12,632kbps

Frame rate:20 frames/second

What's the difference between the two, data rate and total bit rate. thnx

anyway, how to know how many frames are there in video? thnx again

thnx

7. ### Markd77 Senior Member

Sep 7, 2009
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Number of frames is about length X frame rate = 163 seconds X 20 = 3260
Length has probably been rounded to the nearest second so it could be up to 20 frames higher or lower.

8. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
Ok,.

pls help me where i can stream videos online. pls

thnx

9. ### thatoneguy AAC Fanatic!

Feb 19, 2009
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www.ustream.com

That's how a bunch of people in Japan got their video out of the Tsunami and earthquake before services were lost, same goes for the Egypt riots before Egypt killed the Internet routers there.

10. ### Lightfire Thread Starter Well-Known Member

Oct 5, 2010
690
21
Thnx thatoneguy.

I dont know how can i stream a recorded(not live) video.

Help pls.

Thnx

Feb 19, 2009
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718