diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7283d1e..95ffb1a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,6 +14,8 @@ add_executable(fbcp main.c)
 target_link_libraries(fbcp bcm_host)
 
 
+set (CMAKE_C_FLAGS "-std=gnu99 ${CMAKE_C_FLAGS}")
+
 set (CMAKE_C_FLAGS "-std=gnu99 ${CMAKE_C_FLAGS}")
 
 set (CMAKE_C_FLAGS "-std=gnu99 ${CMAKE_C_FLAGS}")
\ No newline at end of file
diff --git a/compile.sh b/compile.sh
new file mode 100755
index 0000000..4f8cc14
--- /dev/null
+++ b/compile.sh
@@ -0,0 +1,8 @@
+
+cd build
+make
+install fbcp /usr/local/bin/fbcp
+
+
+
+
diff --git a/main.c b/main.c
index 3fa5527..b3ad84c 100644
--- a/main.c
+++ b/main.c
@@ -107,7 +107,7 @@ int process_interlaced() {
         }
 
         //not yet sure if needed, but zero out the rest
-        for(int i= (row_offset + 1 % INTERLACE_NUM); i< vinfo.xres * vinfo.yres / 2; i += INTERLACE_NUM) {
+        for(int i= ((row_offset + 1) % INTERLACE_NUM); i< vinfo.xres * vinfo.yres / 2; i += INTERLACE_NUM) {
           p2[i] = 0;
         }