diff --git a/cuda_rasterizer/backward.cu b/cuda_rasterizer/backward.cu
index 4aa41e1c..d58f0683 100644
--- a/cuda_rasterizer/backward.cu
+++ b/cuda_rasterizer/backward.cu
@@ -530,7 +530,7 @@ renderCUDA(
 			// the background color is added if nothing left to blend
 			float bg_dot_dpixel = 0;
 			for (int i = 0; i < C; i++)
-				bg_dot_dpixel += bg_color[i] * dL_dpixel[i];
+				bg_dot_dpixel += bg_color[i + pix_id * C] * dL_dpixel[i];
 			dL_dalpha += (-T_final / (1.f - alpha)) * bg_dot_dpixel;
 
 
diff --git a/cuda_rasterizer/forward.cu b/cuda_rasterizer/forward.cu
index c419a328..369a7f31 100644
--- a/cuda_rasterizer/forward.cu
+++ b/cuda_rasterizer/forward.cu
@@ -369,7 +369,7 @@ renderCUDA(
 		final_T[pix_id] = T;
 		n_contrib[pix_id] = last_contributor;
 		for (int ch = 0; ch < CHANNELS; ch++)
-			out_color[ch * H * W + pix_id] = C[ch] + T * bg_color[ch];
+			out_color[ch * H * W + pix_id] = C[ch] + T * bg_color[ch + pix_id * CHANNELS];
 	}
 }
 
diff --git a/diff_gaussian_rasterization/__init__.py b/diff_gaussian_rasterization/__init__.py
index bbef37d1..f5a3fe7b 100644
--- a/diff_gaussian_rasterization/__init__.py
+++ b/diff_gaussian_rasterization/__init__.py
@@ -55,10 +55,14 @@ def forward(
         cov3Ds_precomp,
         raster_settings,
     ):
+        # Flatten from CxHxW
+        bg = raster_settings.bg if len(raster_settings.bg.shape) == 1 else raster_settings.bg.permute(1,2,0).flatten()
+        pixel_count = raster_settings.image_height * raster_settings.image_width
+        bg = bg if len(bg) > 3 else bg.repeat(pixel_count)
 
         # Restructure arguments the way that the C++ lib expects them
         args = (
-            raster_settings.bg, 
+            bg,
             means3D,
             colors_precomp,
             opacities,
@@ -105,8 +109,13 @@ def backward(ctx, grad_out_color, _):
         raster_settings = ctx.raster_settings
         colors_precomp, means3D, scales, rotations, cov3Ds_precomp, radii, sh, geomBuffer, binningBuffer, imgBuffer = ctx.saved_tensors
 
+        # Flatten from CxHxW
+        bg = raster_settings.bg if len(raster_settings.bg.shape) == 1 else raster_settings.bg.permute(1,2,0).flatten()
+        pixel_count = raster_settings.image_height * raster_settings.image_width
+        bg = bg if len(bg) > 3 else bg.repeat(pixel_count)
+
         # Restructure args as C++ method expects them
-        args = (raster_settings.bg,
+        args = (bg,
                 means3D, 
                 radii, 
                 colors_precomp,