diff --git a/src/zm_monitor.cpp b/src/zm_monitor.cpp
index 0465ecd39..23efda05a 100644
--- a/src/zm_monitor.cpp
+++ b/src/zm_monitor.cpp
@@ -2020,7 +2020,7 @@ bool Monitor::Analyse() {
                 ) ) {
             Debug(1, "assigning refimage from v-channel");
             Image v_image(snap->in_frame->width,
-                snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[3], 0);
+                snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[2], 0);
             ref_image.Assign(v_image);
           } else if (snap->image) {
             Debug(1, "assigning refimage from snap->image");
@@ -2110,7 +2110,7 @@ bool Monitor::Analyse() {
                       ((AVPixelFormat)snap->in_frame->format == AV_PIX_FMT_YUVJ420P)
                       ) ) {
                   Debug(1, "assigning refimage from v-channel");
-                  Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[3], 0);
+                  Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[2], 0);
                   ref_image.Assign(v_image);
                 } else {
             Debug(1, "assigning refimage from snap->image");
@@ -2125,7 +2125,7 @@ bool Monitor::Analyse() {
                       ||
                       ((AVPixelFormat)snap->in_frame->format == AV_PIX_FMT_YUVJ420P)
                       ) ) {
-                  Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[3], 0);
+                  Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[2], 0);
                   snap->score = DetectMotion(v_image, zoneSet);
                 } else {
                   snap->score = DetectMotion(*(snap->image), zoneSet);
@@ -2350,7 +2350,7 @@ bool Monitor::Analyse() {
                     ((AVPixelFormat)snap->in_frame->format == AV_PIX_FMT_YUVJ420P)
                     ) ) {
                 Debug(1, "Assigning from vchannel");
-                Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[3], 0);
+                Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[2], 0);
                 ref_image.Assign(v_image);
               } else if (snap->image) {
                 Debug(1, "Assigning");
@@ -2365,7 +2365,7 @@ bool Monitor::Analyse() {
                   )
                  ) {
                 Debug(1, "Blending from vchannel");
-                Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[3], 0);
+                Image v_image(snap->in_frame->width, snap->in_frame->height, 1, ZM_SUBPIX_ORDER_NONE, snap->in_frame->data[2], 0);
                 ref_image.Blend(v_image, ( state==ALARM ? alarm_ref_blend_perc : ref_blend_perc ));
               } else if (snap->image) {
                 Debug(1, "Blending because %p and format %d != %d, %d", snap->in_frame,