fork download
copy 
  1. #include <stdio.h>
  2. #include <stdlib.h>
  3. #include <mpi.h>
  4.  
  5. #define MASTER_RANK 0
  6. #define BLUR_RADIUS 1
  7.  
  8. // Function to blur a pixel
  9. void blurPixel(unsigned char *image, int width, int x, int y) {
  10.     int sum = 0;
  11.     int count = 0;
  12.     for (int i = x - BLUR_RADIUS; i <= x + BLUR_RADIUS; i++) {
  13.         for (int j = y - BLUR_RADIUS; j <= y + BLUR_RADIUS; j++) {
  14.             if (i >= 0 && i < width && j >= 0 && j < width) {
  15.                 sum += image[i * width + j];
  16.                 count++;
  17.             }
  18.         }
  19.     }
  20.     image[x * width + y] = (unsigned char)(sum / count);
  21. }
  22.  
  23. // Function to blur a block of the image
  24. void blurBlock(unsigned char *block, int width, int block_size) {
  25.     for (int i = 0; i < block_size; i++) {
  26.         for (int j = 0; j < block_size; j++) {
  27.             blurPixel(block, width, i, j);
  28.         }
  29.     }
  30. }
  31.  
  32. int main(int argc, char *argv[]) {
  33.     int rank, size;
  34.     int image_size = 512;
  35.     int block_size = 64;
  36.     int num_blocks = image_size / block_size;
  37.  
  38.     MPI_Init(&argc, &argv);
  39.     MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  40.     MPI_Comm_size(MPI_COMM_WORLD, &size);
  41.  
  42.     // Check if number of processes is valid
  43.     if (size != num_blocks * num_blocks) {
  44.         if (rank == MASTER_RANK) {
  45.             printf("Number of processes must equal the number of image blocks\n");
  46.         }
  47.         MPI_Finalize();
  48.         return EXIT_FAILURE;
  49.     }
  50.  
  51.     // Generate image data on the master process
  52.     unsigned char *image = NULL;
  53.     if (rank == MASTER_RANK) {
  54.         image = (unsigned char *)malloc(image_size * image_size * sizeof(unsigned char));
  55.         // Initialize image with random data
  56.         for (int i = 0; i < image_size * image_size; i++) {
  57.             image[i] = rand() % 256;
  58.         }
  59.     }
  60.  
  61.     // Scatter image blocks to processes
  62.     unsigned char *block = (unsigned char *)malloc(block_size * block_size * sizeof(unsigned char));
  63.     MPI_Scatter(image, block_size * block_size, MPI_UNSIGNED_CHAR, block, block_size * block_size, MPI_UNSIGNED_CHAR, MASTER_RANK, MPI_COMM_WORLD);
  64.  
  65.     // Process the block
  66.     blurBlock(block, block_size, block_size);
  67.  
  68.     // Gather processed blocks back to master process
  69.     MPI_Gather(block, block_size * block_size, MPI_UNSIGNED_CHAR, image, block_size * block_size, MPI_UNSIGNED_CHAR, MASTER_RANK, MPI_COMM_WORLD);
  70.  
  71.     // Print the processed image
  72.     if (rank == MASTER_RANK) {
  73.         printf("Processed Image:\n");
  74.         for (int i = 0; i < image_size; i++) {
  75.             for (int j = 0; j < image_size; j++) {
  76.                 printf("%3d ", image[i * image_size + j]);
  77.             }
  78.             printf("\n");
  79.         }
  80.     }
  81.  
  82.     // Cleanup
  83.     free(image);
  84.     free(block);
  85.     MPI_Finalize();
  86.  
  87.     return EXIT_SUCCESS;
  88. }
  89.  
Success #stdin #stdout #stderr 0.23s 40860KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Standard output is empty
stderr
copy 
Error: unexpected '/' in "/"
Execution halted
https://ideone.com/nhM3M4
language:
R (R 3.5.2)
created:
22 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!