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How many videos can you watch with 2 GB of data?

Can someone help me what apprach should I take to calcualte the bit rate and frame size for different type of resolution
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Size of a Video = FPS * Total Time in Seconds * Size of each frame

FPS = 30 - For Youtube or 24 for Movies - Assumption Youtube

Size of each frame = Quality of frame * 1 bit

= 1280*720*1 bits

= 1 Million bits

= 12.5 Kb per frame

2 Million Kb = 30*Time(seconds)*12.5 Kb

time = 5333 seconds = 88 minutes - Uncompressed video

If we were to compress and let's assume a compression factor of 0.8, then we can watch 88/0.8 = 111 minutes ~ 2 hrs long video.

 

 

 

 

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Nice work Vamsi. Brief and accurate.
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So size goes hand in hand with resolution. And that is height, width , pixel depth.

I will ask if it is black and white or color to know pixel depth (1 byte for B&W and 3 bytes for color, one for each RGB).

Assuming here it's color.

 

I will ask if this is for a youtube video or a film to be displayed in a cinema.

a) If youtube, I'll assume 720p: 1280x720 px.

b) If cinema, I'll assume it's 1000x a).

For a ) then it's ~1 million => 3 million bytes per image=> ~ 3MB/image

For b) ~3GB /image

Then I'll assume it's for a youtube video.

 

Now there's the FPS (frames per second). 25/30 fps is good for the human eye.

Then we have 30 FPS x 3 MB= 60 MB/second

Therefore we have (2000 MB / 60 MB/sec) = ~30 sec or half a minute

This sound incredibly little to me, however, based on videos I have crated/ downloaded. So I will adjust for compression, which is normally used when dealing with video.

I will assume the compression can reduce size to only a 10%

Therefore we could potentially have 6 MB/second => (2000 MB/ 6 MB/sec)= ~300 sec or 5 minutes.
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what are the factors that can affect this? make assumptions around the same

An app to set the baseline - Assume Youtube

Is the video compressed or uncompressed: Compressed

FPS - assume 30

Resolution - assuming 720 P

I know that an hour of 720 P footage is roughly a 1 GB to stream , 2 GB will get you about 2 hours of footage viewing.

You can similarly back calculate other resolutions by proporionately adjusting so for  480P for example you'll get 3 hours of viewing
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