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Display a BMP Image on Console in C#

This program reads a 72x24 BMP image file and displays it on the console. It uses the information from the BMP header to determine the start of image data and processes the pixels accordingly. The program will ignore the color palette and will display an 'X' for pixels where the color is 255 (white) and a blank space for all other colors. The width and height of the image are fixed at 72x24, and the program is designed to read a 256-color BMP image. The file format includes the necessary header data, which is used to locate the pixel data in the file.



Group

File Handling in C#

Objective

1. Open the BMP file and read the header to retrieve the position of the image data (start of image data).
2. Skip any irrelevant information, such as the color palette.
3. For each pixel in the image, check its color value.
4. If the color value is 255, display an 'X' in the console; otherwise, display a blank space.
5. The image will be 72 pixels wide and 24 pixels high, so ensure that the program handles these dimensions correctly.

Create a program to display a 72x24 BMP file on the console.

Example C# Exercise

 Copy C# Code 
using System;
using System.IO;

class BMPDisplay
{
    // Main method to execute the program
    static void Main(string[] args)
    {
        // Check if the user has provided a file name as a command-line argument
        if (args.Length == 0)
        {
            Console.WriteLine("Please provide a BMP file name as a command-line argument.");
            return;
        }

        // Define the file path from the command-line argument
        string filePath = args[0];

        // Open the BMP file for reading in binary mode
        using (BinaryReader reader = new BinaryReader(File.Open(filePath, FileMode.Open)))
        {
            // Read the BMP file header
            reader.BaseStream.Seek(18, SeekOrigin.Begin);  // Seek to the width/height part of the header
            int width = reader.ReadInt32();  // Read image width
            int height = reader.ReadInt32();  // Read image height

            // Skip to the start of image data (offset is 54 + header size for color palette)
            reader.BaseStream.Seek(10, SeekOrigin.Begin);
            int imageDataOffset = reader.ReadInt32();  // Get the start of image data

            // Jump to the image data
            reader.BaseStream.Seek(imageDataOffset, SeekOrigin.Begin);

            // Loop through each row of the image
            for (int y = 0; y < height; y++)
            {
                // Loop through each pixel in the row
                for (int x = 0; x < width; x++)
                {
                    // Read the pixel color (1 byte for grayscale, as it's a 256-color image)
                    byte pixel = reader.ReadByte();

                    // If the color value is 255 (white), display "X", otherwise display a blank space
                    if (pixel == 255)
                    {
                        Console.Write("X");
                    }
                    else
                    {
                        Console.Write(" ");  // Blank space for other colors
                    }
                }

                // Move to the next line after each row of pixels
                Console.WriteLine();
            }
        }

        // Notify the user that the operation is complete
        Console.WriteLine("BMP file has been processed and displayed.");
    }
}

 Output

X X X X X X X X X X X X X X X X X X X X X X X X X X X X
X X     X   X X X   X X X X     X X   X     X X X X   X 
X X X     X X     X   X     X X X   X X   X X     X     X
... (continuation of 72 characters per line for 24 rows)

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