video_files:formulas
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Table of Contents
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.
Picture 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.
Sound File Size
Sound File Size = sample rate x duration x bit depth x number of channels
NOTE:
- sample rate: The number of samples being recorded per second; (such as 48,000 samples per second).
- duration: In seconds.
- bit depth: The number of bits used to record one sample.
- Retro-arcade games used to use 8-bit music. Old mobile phones used to use 16-bit ringtones. Higher quality sound files may use a 32-bit bit-depth or higher.
- 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).
- channels: 1 is mono, 2 is stereo, 6 is dolby-surround.
video_files/formulas.1747433863.txt.gz · Last modified: 2025/05/16 22:17 by peter