Understanding Bitmap Image Data Representation and File Size Calculation
This content delves into the fundamentals of bitmap images, covering topics such as resolution, color depth, file size calculation, and metadata. Explore how different parameters affect the quality and size of images, with practical examples and activities to enhance learning.
Uploaded on Jul 15, 2024 | 0 Views
Download Presentation
![](/assets/img/so-down.gif)
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. Download presentation by click this link. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
E N D
Presentation Transcript
Starter Complete the worksheet quiz on bitmap images. 2
Objective of the sesson Understand how computers store bitmap images. Explain how files are saved in bitmaps and how size and colour depth can affect the file size of an image. 3
Resolution The resolution describes how big the pixels are in the image. The higher the resolution the better quality the image is. It is usually measures in pixels per inch. If you make a bitmap image larger then often it will become pixelated as the pixels have to become bigger to fill the space you want. 4
Example I m a bitmap image. I was made as a thumbnail for a profile picture. When viewed at my original size I look fine. If you enlarge me. I pixelate. I have a low quality. Not many pixels are used to make me. 5
File size In order to work out the image size you would need to know: The size of the grid (width and depth) The number of bits per pixel for the colour depth For instance an image which is 1000 x 800 pixels with a 16 bit colour depth would be: (1000 x 800) x 16 = 12,800,000 bits There are 8 bits in a byte 12,800,000 / 8 = 1,600,000 This is more commonly written as 16KB. 6
Example I m 1000 pixels wide and 800 pixels high. 1000 x 800 is 800,000 pixels. Each of those 800,000 pixels is represented by a 16 bit number. 800,000 x 16 = 12,800,000 There are 8 bits in a byte so divide by 8 to convert to bytes. 12,800,000 / 8 = 1,600,000 There are 1,000 bytes in a Kilobyte so divide by 1000 to find the size in kilobytes. 1,600,000 / 1,000 = 16KB 7
Activity Complete the worksheet on file size. 8
Meta Data Meta Data is at the beginning of a file to tell the computer how to process the data. What sort of information would need to be included in the meta data? Size of the image grid (width and height) Colour depth (number of bits per pixel) Resolution to display the image in (pixels per inch) 9
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 10
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 This shows that the data that follows is to be treated as an image. 11
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 Image width size. 12
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 Image height size. 13
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 Colour depth. 14
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 Resolution. 15
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 Image data. 16
Example of an image in binary. 01101010110101001010011101001100010101101010001010100101110101010111010100101001010 10100101010101000101010101000010101011000101010101101010101000101010101000101010101 01000101010101010100010101011101010110010101000010100010011000101010100100010101000 11010101101010010100111010011000101011010100010101001011101010101110101001010010101 01001010101010001010101010000101010110001010101011010101010001010101010001010101010 10001010101010101000101010111010101100101010011010101101010010100111010011000101011 01010001010100101110101010111010100101001010101001010101010001010101010000101010110 00101010101101010101000101010101000101010101010001010101010101000101010111010101100 10101001101010110101001010011101001100010101101010001010100101110101010111010100101 00101010100101010101000101010101000010101011000101010101101010101000101010101000101 01010101000101010101010100010101011101010110010101001101010110101001010011101001100 01010110101000101010010111010101011101010010100101010100101010101000101010101000010 10101100010101010110101010100010101010100010101010101000101010101010100010101011101 01011001010100110101011010100101001110100110001010110101000101010010111010101011101 01001010010101010010101010100010101010100001010101100010101010110101010100010101010 10001010101010100010101010101010001010101110101011001010100110101011010100101001110 10011000101011010100010101001011101010101110101001010010101010010101010100010101010 10000101010110001010101011010101010001010101010001010101010100010101010101010001010 10111010101100101010011010101101010010100111010011000101011010100010101001011101010 10111010100101001010101001010101010001010101010000101010110001010101011010101010001 01010101000101010101010001010101010101000101010111010101100101010011010101101010010 10011101001100010101101010001010100101110101010111010100101001010101001010101010001 01010101000010101011000101010101101010101000101010101000101010101010001010101010101 00010101011101010110010101010100010101010100001010101100010101101010001010110110101 End of image file message. 17
Pause for thought Consider what is happening next time you look at an image on any digital device. Will you ever look at an image the same again? 18