2 files changed, 2 insertions, 1 deletions
diff --git a/libcrystfel/src/image.c b/libcrystfel/src/image.c
index 8de16bd5..de27308c 100644
--- a/libcrystfel/src/image.c
+++ b/libcrystfel/src/image.c
@@ -861,7 +861,7 @@ static int read_cbf(struct imagefile *f, struct image *image)
 /****************************** Image files ***********************************/
 
 
-static signed int is_cbf_file(const char *filename)
+signed int is_cbf_file(const char *filename)
 {
 	FILE *fh;
 	char line[1024];
diff --git a/libcrystfel/src/image.h b/libcrystfel/src/image.h
index c900bd29..99c3d57e 100644
--- a/libcrystfel/src/image.h
+++ b/libcrystfel/src/image.h
@@ -271,6 +271,7 @@ extern void imagefile_copy_fields(struct imagefile *f,
                                   const struct imagefile_field_list *copyme,
                                   FILE *fh, struct event *ev);
 extern void imagefile_close(struct imagefile *f);
+extern signed int is_cbf_file(const char *filename);
 
 /* Field lists */
 extern struct imagefile_field_list *new_imagefile_field_list(void);