Documentation: C API comments in include/

include/c/sk_image.h

Index: include/c/sk_image.h
diff --git a/include/c/sk_image.h b/include/c/sk_image.h
index e6f49b74ee89b1819f7afa1ad725822165e15999..e90649d75d492030bed8ee3e5d2aa58b738f8163 100644
--- a/include/c/sk_image.h
+++ b/include/c/sk_image.h
@@ -30,12 +30,40 @@ SK_API sk_image_t* sk_image_new_raster_copy(const sk_imageinfo_t*, const void* p
  */
 SK_API sk_image_t* sk_image_new_from_encoded(const sk_data_t* encoded, const sk_irect_t* subset);
 
+/**
+ *  Encode the image's pixels and return the result as a new PNG in a
+ *  sk_data_t, which the caller must manage: call sk_data_unref() when
+ *  they are done.
+ *
+ *  If the image type cannot be encoded, this will return NULL.
+ */
 SK_API sk_data_t* sk_image_encode(const sk_image_t*);
 
+/**
+ *  Increment the reference count on the given sk_image_t. Must be
+ *  balanced by a call to sk_image_unref().
+*/
 SK_API void sk_image_ref(const sk_image_t*);
+/**
+ *  Decrement the reference count. If the reference count is 1 before
+ *  the decrement, then release both the memory holding the sk_image_t
+ *  and the memory it is managing.  New sk_image_t are created with a
+    reference count of 1.
+*/
 SK_API void sk_image_unref(const sk_image_t*);
+
+/**
+ *  Return the width of the sk_image_t/
+ */
 SK_API int sk_image_get_width(const sk_image_t*);
+/**
+ *  Return the height of the sk_image_t/
+ */
 SK_API int sk_image_get_height(const sk_image_t*);
+
+/**
+ *  Returns a non-zero value unique among all images.
+ */
 SK_API uint32_t sk_image_get_unique_id(const sk_image_t*);
 
 SK_C_PLUS_PLUS_END_GUARD