diff --git a/libs/gui/ISurfaceComposer.cpp b/libs/gui/ISurfaceComposer.cpp
index fa2f59a..74c3bed 100644
--- a/libs/gui/ISurfaceComposer.cpp
+++ b/libs/gui/ISurfaceComposer.cpp
@@ -104,7 +104,7 @@
     virtual status_t captureScreen(const sp<IBinder>& display,
             const sp<IGraphicBufferProducer>& producer,
             Rect sourceCrop, uint32_t reqWidth, uint32_t reqHeight,
-            uint32_t minLayerZ, uint32_t maxLayerZ,
+            int32_t minLayerZ, int32_t maxLayerZ,
             bool useIdentityTransform,
             ISurfaceComposer::Rotation rotation)
     {
@@ -115,8 +115,8 @@
         data.write(sourceCrop);
         data.writeUint32(reqWidth);
         data.writeUint32(reqHeight);
-        data.writeUint32(minLayerZ);
-        data.writeUint32(maxLayerZ);
+        data.writeInt32(minLayerZ);
+        data.writeInt32(maxLayerZ);
         data.writeInt32(static_cast<int32_t>(useIdentityTransform));
         data.writeInt32(static_cast<int32_t>(rotation));
         remote()->transact(BnSurfaceComposer::CAPTURE_SCREEN, data, &reply);
@@ -544,8 +544,8 @@
             data.read(sourceCrop);
             uint32_t reqWidth = data.readUint32();
             uint32_t reqHeight = data.readUint32();
-            uint32_t minLayerZ = data.readUint32();
-            uint32_t maxLayerZ = data.readUint32();
+            int32_t minLayerZ = data.readInt32();
+            int32_t maxLayerZ = data.readInt32();
             bool useIdentityTransform = static_cast<bool>(data.readInt32());
             int32_t rotation = data.readInt32();