3 files changed, 27 insertions, 4 deletions

diff --git a/src/callbacks.c b/src/callbacks.c
index 732b79c..cd72a19 100644
--- a/src/callbacks.c
+++ b/src/callbacks.c
@@ -766,7 +766,7 @@ void zoom_change(GtkScale *sc1, cam_t *cam)
 {
 
     cam->zoom = 256 * (int)gtk_range_get_value((GtkRange *) sc1);
-    v4l2_set_control(cam->dev, V4L2_CID_ZOOM_ABSOLUTE, cam->zoom);
+    v4l2_set_control(cam->dev, cam->zoom_cid, cam->zoom);
 }
 
 void colour_change(GtkScale *sc1, cam_t *cam)
diff --git a/src/v4l.c b/src/v4l.c
index 10c4494..43c9547 100644
--- a/src/v4l.c
+++ b/src/v4l.c
@@ -274,6 +274,29 @@ int camera_cap(cam_t *cam)
     return 0;
 }
 
+static int v4l_get_zoom(cam_t *cam)
+{
+    int i;
+
+    cam->zoom_cid = V4L2_CID_ZOOM_ABSOLUTE;
+    i = v4l2_get_control(cam->dev, cam->zoom_cid);
+    if (i >= 0)
+        return i;
+
+    cam->zoom_cid = V4L2_CID_ZOOM_RELATIVE;
+    i = v4l2_get_control(cam->dev, cam->zoom_cid);
+    if (i >= 0)
+        return i;
+
+    cam->zoom_cid = V4L2_CID_ZOOM_CONTINUOUS;
+    i = v4l2_get_control(cam->dev, cam->zoom_cid);
+    if (i >= 0)
+        return i;
+
+    cam->zoom_cid = -1;
+    return -1;
+}
+
 void get_pic_info(cam_t *cam)
 {
     int i;
@@ -297,8 +320,8 @@ void get_pic_info(cam_t *cam)
     } else {
         cam->colour = -1;
     }
-    i = v4l2_get_control(cam->dev, V4L2_CID_ZOOM_ABSOLUTE);
-    if (i >= 0) {
+    i = v4l_get_zoom(cam);
+    if (cam->zoom_cid) {
         cam->zoom = i;
         if (cam->debug == TRUE)
             printf("zoom = %d\n", cam->zoom);
diff --git a/src/v4l.h b/src/v4l.h
index 323f3db..4aaf976 100644
--- a/src/v4l.h
+++ b/src/v4l.h
@@ -55,7 +55,7 @@ typedef struct camera {
     float scale;
     CamoImageSize size;
     char name[32];
-    int contrast, brightness, whiteness, colour, hue, zoom, bytesperline;
+    int contrast, brightness, whiteness, colour, hue, zoom, zoom_cid, bytesperline;
     unsigned int pixformat;
     int frame_number;