diff --git a/libvips/cimg/cimg_dispatch.c b/libvips/cimg/cimg_dispatch.c
index 30397c2b..371fee61 100644
--- a/libvips/cimg/cimg_dispatch.c
+++ b/libvips/cimg/cimg_dispatch.c
@@ -40,6 +40,16 @@
 #include <dmalloc.h>
 #endif /*WITH_DMALLOC*/
 
+/** 
+ * SECTION: cimg_funcs
+ * @short_description: expose operations from the CImg library, mostly noise
+ * removal
+ * @stability: Stable
+ * @include: vips/vips.h
+ *
+ * The GREYCstoration filter.
+ */
+
 static int
 greyc_vec( im_object *argv )
 {
diff --git a/libvips/resample/interpolate.c b/libvips/resample/interpolate.c
index 53379c5d..07e97f99 100644
--- a/libvips/resample/interpolate.c
+++ b/libvips/resample/interpolate.c
@@ -50,7 +50,8 @@
 
 /** 
  * SECTION: interpolate
- * @short_description: shrink, expand, rotate with a choice of interpolators
+ * @short_description: various interpolators: nearest, bilinear, bicubic, and
+ * some non-linear
  * @stability: Stable
  * @include: vips/vips.h
  *
diff --git a/libvips/video/video_dispatch.c b/libvips/video/video_dispatch.c
index 6a9c959e..94f84c9c 100644
--- a/libvips/video/video_dispatch.c
+++ b/libvips/video/video_dispatch.c
@@ -40,6 +40,16 @@
 #include <dmalloc.h>
 #endif /*WITH_DMALLOC*/
 
+/** 
+ * SECTION: video
+ * @short_description: various video grabbers
+ * @see_also: <link linkend="libvips-image">image</link>
+ * @stability: Stable
+ * @include: vips/vips.h
+ *
+ * Read an image from a video source.
+ */
+
 static int
 video_v4l1_vec( im_object *argv )
 {