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.
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.
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
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
2 likes | 0 feedback
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