diff --git a/gopro_8:7/preset_gopro_8:7.py b/gopro_8:7/preset_gopro_8:7.py
index f3e5b5d..734bebc 100644
--- a/gopro_8:7/preset_gopro_8:7.py
+++ b/gopro_8:7/preset_gopro_8:7.py
@@ -103,7 +103,7 @@ adm.addVideoFilter(
     "shaderLoader", "shaderFile=/opt/rk/avidemux/unfish_gopro_8:7.glsl")
 adm.addVideoFilter(
     "swscale",
-    "width=2832",
+    "width=2468",
     "height=2160",
     "algo=2",
     "sourceAR=0",
diff --git a/gopro_8:7/unfish_gopro_8:7.glsl b/gopro_8:7/unfish_gopro_8:7.glsl
index 1ef55c9..3fc0b91 100644
--- a/gopro_8:7/unfish_gopro_8:7.glsl
+++ b/gopro_8:7/unfish_gopro_8:7.glsl
@@ -20,7 +20,7 @@
 
 #define color_conversion
 #define texture_filtering
-//#define rotate_180
+#define rotate_180
 //#define debug_borders
 
 #undef highp // defined by Qt-OpenGl
@@ -37,7 +37,6 @@ uniform float pts;
 // parameters
 
 const vec2  sensor_size              = vec2(5.949440, 5.205760);
-const vec2  rectilinear_scale        = vec2(1.147370, 1.0);
 const float equidistant_focal_length = 2.920000;
 const float rectilinear_focal_length = 2.102263;
 
@@ -56,7 +55,7 @@ vec2 sensor_to_texture;
 
 void initialize() {
     texture_center = myResolution * 0.5;
-    texture_to_sensor = (sensor_size / myResolution) * rectilinear_scale;
+    texture_to_sensor = (sensor_size / myResolution);
 #ifdef rotate_180
     texture_to_sensor *= -1.0;
 #endif
diff --git a/gopro_8:7/unfish_gopro_8:7.py b/gopro_8:7/unfish_gopro_8:7.py
index f3db0b2..d1fe816 100644
--- a/gopro_8:7/unfish_gopro_8:7.py
+++ b/gopro_8:7/unfish_gopro_8:7.py
@@ -87,26 +87,19 @@ print("linear fov  : horizontal = %7.3f, vertical = %7.3f, diagonal = %7.3f (deg
 
 print("\n--- shader parameters ---\n")
 
-output_size_horizontal = 2.0 * rectilinear_radius(gopro_fov_horizontal * 0.5)
-output_size_vertical   = gopro_size_vertical
-
-output_scale_horizontal = output_size_horizontal / gopro_size_horizontal
-
 print("""// parameters\n
 const vec2  sensor_size              = vec2(%.6f, %.6f);
-const vec2  rectilinear_scale        = vec2(%.6f, 1.0);
 const float equidistant_focal_length = %.6f;
 const float rectilinear_focal_length = %.6f;""" % (
     gopro_size_horizontal, gopro_size_vertical,
-    output_scale_horizontal,
     gopro_focal_length,
     rectilinear_focal_length_vertical)
 )
 
-print("\n--- filters parameters ---\n")
+print("\n--- output size ---\n")
 
 def print_output_array(array_vertical):
-    array_horizontal = (array_vertical / gopro_array_vertical) * gopro_array_horizontal * output_scale_horizontal
+    array_horizontal = (array_vertical / gopro_array_vertical) * gopro_array_horizontal
     print("resize: width = %d, height = %d" % (
         round(array_horizontal / 4.0) * 4,
         array_vertical))