Make example program to take command line arguments

examples/ppm.c

@@ -1,4 +1,6 @@
-// examples/ppm.c
+/* examples/ppm.c
+ *   $ ./ppm source! mask! result? context? neighbors? probes?
+ */
 #include <stdlib.h>
 #include <stdio.h>
 
@@ -37,6 +39,11 @@ static struct ppm *
 ppm_read(const char *filename)
 {
     FILE *f = fopen(filename, "rb");
+    if (f == NULL)
+    {
+        perror(filename);
+        return NULL;
+    }
     struct ppm *m;
     long width, height;
     if (fscanf(f, "P6 %ld%ld%*d%*c", &width, &height) < 2)
@@ -47,15 +54,29 @@ ppm_read(const char *filename)
     return m;
 }
 
-int main()
+int main(int argc, char **argv)
 {
+    const char *source_in   = argc > 1 ? argv[1] : NULL;
+    const char *mask_in     = argc > 2 ? argv[2] : NULL;
+    const char *result_out  = argc > 3 ? argv[3] : "out.ppm";
+    const int context       = argc > 4 ? atoi(argv[4]) : 1;
+    const int neighbors     = argc > 5 ? atoi(argv[5]) : 9;
+    const int probes        = argc > 6 ? atoi(argv[6]) : 64;
+
+    printf("context: %d neighbors: %d probes: %d\n", context, neighbors, probes);
 #ifdef _WIN32
     int _setmode(int, int);
     _setmode(0, 0x8000);
     _setmode(1, 0x8000);
 #endif
-    struct ppm *source_ppm = ppm_read("assets/source.ppm");
-    struct ppm *mask_ppm = ppm_read("assets/mask.ppm");
+    struct ppm *source_ppm = ppm_read(source_in);
+    struct ppm *mask_ppm = ppm_read(mask_in);
+
+    if (source_ppm == NULL || mask_ppm == NULL)
+    {
+        fprintf(stderr, "Source or mask image not provided.\n");
+        exit(EXIT_FAILURE);
+    }
 
     unsigned char *mask_grayscale = malloc(mask_ppm->width * mask_ppm->height);
 
@@ -82,23 +103,24 @@ int main()
     TImageSynthParameters params = {
         .isMakeSeamlesslyTileableHorizontally = FALSE,
         .isMakeSeamlesslyTileableVertically = FALSE,
-        .matchContextType = 2,
+        .matchContextType = context,
         .mapWeight = 0.5f,
         .sensitivityToOutliers = 0.117f,
-        .patchSize = 9,
-        .maxProbeCount = 50,
+        .patchSize = neighbors,
+        .maxProbeCount = probes,
     };
 
     int cancel_token = 0;
     int error = 0;
 
     error = imageSynth(&source_buffer, &mask_buffer, T_RGB, &params, NULL, NULL, &cancel_token);
 
-    printf("Task finished with the error code: %d\n", error);
+    if (error != 0)
+        fprintf(stderr, "Operation failed. Error code: %d\n", error);
 
-    FILE *file_result = fopen("ppm_result.ppm", "wb");
-    ppm_write(source_ppm, file_result);
-    fclose(file_result);
+    FILE *result_file = fopen(result_out, "wb");
+    ppm_write(source_ppm, result_file);
+    fclose(result_file);
 
     free(source_ppm);
     free(mask_ppm);