diff --git a/cmd/main.c b/cmd/main.c
index 2d39330..7caf237 100644
--- a/cmd/main.c
+++ b/cmd/main.c
@@ -59,13 +59,13 @@ option_t all_options[] = {
   DEFINE_OPTION_VALUES(camera, format, camera_formats),
   DEFINE_OPTION(camera, nbufs, uint),
   DEFINE_OPTION(camera, fps, uint),
-  DEFINE_OPTION(camera, allow_dma, bool),
+  DEFINE_OPTION_DEFAULT(camera, allow_dma, bool, "1"),
   DEFINE_OPTION(camera, high_res_factor, float),
   DEFINE_OPTION(camera, low_res_factor, float),
   DEFINE_OPTION(http, port, uint),
   DEFINE_OPTION(http, maxcons, uint),
-  DEFINE_OPTION(log, debug, bool),
-  DEFINE_OPTION(log, verbose, bool),
+  DEFINE_OPTION_DEFAULT(log, debug, bool, "1"),
+  DEFINE_OPTION_DEFAULT(log, verbose, bool, "1"),
   {}
 };
 
diff --git a/csi_camera.sh b/csi_camera.sh
index 87e4775..bf68303 100755
--- a/csi_camera.sh
+++ b/csi_camera.sh
@@ -2,4 +2,4 @@
 
 set -xeo pipefail
 make
-./camera_stream -camera-path /dev/v4l/by-path/*.csi-video-index0 "$@"
+./camera_stream -camera-path=$(echo /dev/v4l/by-path/*.csi-video-index0) "$@"
diff --git a/opts/opts.c b/opts/opts.c
index 9785700..bde0f58 100644
--- a/opts/opts.c
+++ b/opts/opts.c
@@ -29,18 +29,28 @@ static void print_help(option_t *options)
   }
 }
 
-static int parse_opt(option_t *options, const char *key, const char *value)
+static int parse_opt(option_t *options, const char *key)
 {
   option_t *option = NULL;
+  const char *value = strchr(key, '=');
 
   for (int i = 0; options[i].name; i++) {
-    if (!strcmp(key, options[i].name)) {
-      option = &options[i];
-      break;
+    if (value) {
+      if (!strncmp(key, options[i].name, value - key)) {
+        option = &options[i];
+        value++; // ignore '='
+        break;
+      }
+    } else {
+      // require exact match
+      if (!strcmp(key, options[i].name)) {
+        option = &options[i];
+        value = option->default_value;
+        break;
+      }
     }
   }
-
-  if (!option) {
+  if (!option || !value) {
     return -EINVAL;
   }
 
@@ -68,22 +78,23 @@ int parse_opts(option_t *options, int argc, char *argv[])
 
   for (arg = 1; arg < argc; arg += 2) {
     const char *key = argv[arg];
-    if (!strcmp(key, "-help")) {
+
+    if (key[0] == '-') {
+      key++;
+      if (key[0] == '-')
+        key++;
+    } else {
+      E_LOG_ERROR(NULL, "The '%s' is not option (should start with - or --).", key);
+    }
+
+    if (!strcmp(key, "help")) {
       print_help(options);
       return -1;
     }
 
-    if (arg+1 == argc) {
-      E_LOG_ERROR(NULL, "The %s is missing argument.", key);
-    }
-
-    if (key[0] != '-') {
-      E_LOG_ERROR(NULL, "The '%s' is not option (should start with -).", key);
-    }
-
-    int ret = parse_opt(options, key+1, argv[arg+1]);
+    int ret = parse_opt(options, key);
     if (ret <= 0) {
-      E_LOG_ERROR(NULL, "Parsing '%s %s' returned '%d'.", key, argv[arg+1], ret);
+      E_LOG_ERROR(NULL, "Parsing '%s' returned '%d'.", argv[arg], ret);
     }
   }
 
diff --git a/opts/opts.h b/opts/opts.h
index 3b1759f..db6b33e 100644
--- a/opts/opts.h
+++ b/opts/opts.h
@@ -21,6 +21,7 @@ typedef struct options_s {
   const char *help;
   option_value_t *value_mapping;
   unsigned size;
+  const char *default_value;
 } option_t;
 
 #define lambda(return_type, function_body) \
@@ -43,6 +44,15 @@ typedef struct options_s {
     .size = sizeof(_section##_options._name), \
   }
 
+#define DEFINE_OPTION_DEFAULT(_section, _name, _type, _default_value) \
+  { \
+    .name = #_section "-" #_name, \
+    .value_##_type = &_section##_options._name, \
+    .format = OPTION_FORMAT_##_type, \
+    .size = sizeof(_section##_options._name), \
+    .default_value = _default_value, \
+  }
+
 #define DEFINE_OPTION_VALUES(_section, _name, _value_mapping) \
   { \
     .name = #_section "-" #_name, \
diff --git a/usb_camera.sh b/usb_camera.sh
index 8f65d99..ec2ad4e 100755
--- a/usb_camera.sh
+++ b/usb_camera.sh
@@ -2,4 +2,4 @@
 
 set -xeo pipefail
 make
-./camera_stream -camera-path /dev/v4l/by-id/usb-*-video-index0 "$@"
+./camera_stream -camera-path=$(echo /dev/v4l/by-id/usb-*-video-index0 ) "$@"