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Video Files - Formulas

File size = bitrate * number of minutes * .0075
Bitrate = file size / (number of minutes * .0075)
Number of minutes = file size / (bitrate * .0075)

otherwise

GB = mbps * minutes * .0075
mbps = GB / (minutes * .0075)
minutes = GB / (mbps * .0075)

NOTE: The .0075 is derived from the following:

As there are 8 bits per byte, it is required to device by 8 to determine the bits.
To convert the number of minutes to seconds, multiply by 60.
Divide by 1,000 to to convert megabits (Mb) to megabytes (MB), or megabytes to gigabytes.

1/8 * 60 / 1000 = 0.0075.

File Size

File Size = width x height x colour depth x frame rate x duration

NOTE:

width: In pixels.
height: In pixels.
color depth: The number of bits used to encode the colour of one pixel.
- A 1-bit colour depth means that the graphic can only include 2 colours (e.g. 1 = black, 0 = white).
- A 8-bit colour depth means that the graphic can include up to 256 colours.
- A 3-Byte colour depth (RGB code) would include 16,777,216 colours.
  - RGB would have a color depth of 3 (24 bits; 8 bits for Red, 8 bits for Green, 8 bits for Blue).
- A 4-Byte color depth (RGBA) can also be used. (32 bits; 8 bits for Red, 8 bits for Green, 8 bits for Blue; 8 bits for Alpha).
frame rate: in fps (frame per seconds).
duration: in seconds.