1 files changed, 34 insertions, 12 deletions
diff --git a/docs/manual.md b/docs/manual.md
index 0dd9c66..85584df 100644
--- a/docs/manual.md
+++ b/docs/manual.md
@@ -185,22 +185,18 @@ To synchronously grab frames, first start the camera:
     g_assert_no_error (error);
 ~~~
 
-Now you have two options with regard to memory buffers. If you already have a
-suitable sized buffer, just pass it to `uca_camera_grab`. Otherwise pass a
-pointer pointing to `NULL` (this is different from a `NULL` pointer!). In this
-case memory will be allocated for you:
+Now, you have to allocate a suitably sized buffer and pass it to
+`uca_camera_grab`.
 
 ~~~ {.c}
-    gpointer buffer_1 = NULL;   /* A pointer pointing to NULL */
-    gpointer buffer_2 = g_malloc0 (640 * 480 * 2);
+    gpointer buffer = g_malloc0 (640 * 480 * 2);
 
-    /* Memory will be allocated. Remember to free it! */
-    uca_camera_grab (camera, &buffer_1, &error);
-
-    /* Memory buffer will be used */
-    uca_camera_grab (camera, &buffer_2, &error);
+    uca_camera_grab (camera, buffer, &error);
 ~~~
 
+You have to make sure that the buffer is large enough by querying the size of
+the region of interest and the number of bits that are transferred.
+
 
 ### Getting and setting camera parameters
 
@@ -405,7 +401,7 @@ pm = Uca.PluginManager()
 print(pm.get_available_cameras())
 
 # Load a camera
-cam = pm.get_camera('pco')
+cam = pm.get_camerav('pco', [])
 
 # You can read and write properties in two ways
 cam.set_properties(exposure_time=0.05)
@@ -417,6 +413,32 @@ of the target language. For example with Python, the namespace prefix `uca_`
 becomes the module name `Uca` and dashes separating property names become
 underscores.
 
+Integration with Numpy is relatively straightforward. The most important thing
+is to get the data pointer from a Numpy array to pass it to `uca_camera_grab`:
+
+~~~ {.python}
+import numpy as np
+
+def create_array_from(camera):
+    """Create a suitably sized Numpy array and return it together with the
+    arrays data pointer"""
+    bits = camera.props.sensor_bitdepth
+    dtype = np.uint16 if bits > 8 else np.uint8
+    a = np.zeros((cam.props.roi_height, cam.props.roi_width), dtype=dtype)
+    return a, a.__array_interface__['data'][0]
+
+# Suppose 'camera' is a already available, you would get the camera data like
+# this:
+a, buf = create_array_from(camera)
+camera.start_recording()
+camera.grab(buf)
+
+# Now data is in 'a' and we can use Numpy functions on it
+print(np.mean(a))
+
+camera.stop_recording()
+~~~
+
 
 # Integrating new cameras