Add "framerate" parameter to generic camera (#14079)

* add "framerate" parameter to generic camera

* fix lint

homeassistant/components/camera/generic.py

@@ -28,6 +28,7 @@ _LOGGER = logging.getLogger(__name__)
 CONF_CONTENT_TYPE = 'content_type'
 CONF_LIMIT_REFETCH_TO_URL_CHANGE = 'limit_refetch_to_url_change'
 CONF_STILL_IMAGE_URL = 'still_image_url'
+CONF_FRAMERATE = 'framerate'
 
 DEFAULT_NAME = 'Generic Camera'
 
@@ -40,6 +41,7 @@ PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
     vol.Optional(CONF_PASSWORD): cv.string,
     vol.Optional(CONF_USERNAME): cv.string,
     vol.Optional(CONF_CONTENT_TYPE, default=DEFAULT_CONTENT_TYPE): cv.string,
+    vol.Optional(CONF_FRAMERATE, default=2): cv.positive_int,
 })
 
 
@@ -62,6 +64,7 @@ class GenericCamera(Camera):
         self._still_image_url = device_info[CONF_STILL_IMAGE_URL]
         self._still_image_url.hass = hass
         self._limit_refetch = device_info[CONF_LIMIT_REFETCH_TO_URL_CHANGE]
+        self._frame_interval = 1 / device_info[CONF_FRAMERATE]
         self.content_type = device_info[CONF_CONTENT_TYPE]
 
         username = device_info.get(CONF_USERNAME)
@@ -78,6 +81,11 @@ class GenericCamera(Camera):
         self._last_url = None
         self._last_image = None
 
+    @property
+    def frame_interval(self):
+        """Return the interval between frames of the mjpeg stream."""
+        return self._frame_interval
+
     def camera_image(self):
         """Return bytes of camera image."""
         return run_coroutine_threadsafe(