diff --git a/libavfilter/vf_nlmeans_vulkan.c b/libavfilter/vf_nlmeans_vulkan.c
index a3536eaaf6..e69a0883cc 100644
--- a/libavfilter/vf_nlmeans_vulkan.c
+++ b/libavfilter/vf_nlmeans_vulkan.c
@@ -34,6 +34,7 @@
 #define TYPE_BLOCK_SIZE (TYPE_SIZE * TYPE_BLOCK_ELEMS)
 #define WG_SIZE 32
 
+// prevent macro expansion in GLSL
 #undef isinf
 
 typedef struct NLMeansVulkanContext {
@@ -416,7 +417,7 @@ static av_cold int init_weights_pipeline(FFVulkanContext *vkctx, FFVkExecPool *e
     GLSLC(1,     c_plane = comp_plane[comp_idx];                                 );
     GLSLC(1,     p = patch_size[comp_idx];                                       );
     GLSLC(1,     s = strength[comp_idx];                                         );
-    GLSLC(1,     if (pos.y < p || pos.y >= height[c_plane] - p || pos.x < p || pos.x >= width[c_plane] - p || isinf(s)) );
+    GLSLC(1,     if (isinf(s) || pos.x < p || pos.y < p || pos.x >= width[c_plane] - p || pos.y >= height[c_plane] - p) );
     GLSLC(2,         return;                                                     );
     GLSLC(0,                                                                     );
     GLSLC(1,     offset = integral_size * (invoc_idx * nb_components + comp_idx); );
@@ -424,7 +425,7 @@ static av_cold int init_weights_pipeline(FFVulkanContext *vkctx, FFVkExecPool *e
     for (int i = 0; i < TYPE_ELEMS; i++)
         GLSLF(1, offs[%i] = xyoffsets[xyoffs_start + %i*invoc_idx + %i];         ,i,TYPE_ELEMS,i);
     GLSLC(0,                                                                     );
-    GLSLC(1,     ws_off = ws_count * invoc_idx + ws_offset[comp_idx] + pos.y * ws_stride[comp_idx]; );
+    GLSLC(1,     ws_off = ws_count * invoc_idx + ws_offset[comp_idx] + pos.y * ws_stride[comp_idx] + pos.x; );
     GLSLC(1,     size = imageSize(input_img[c_plane]);                           );
     GLSLC(0,                                                                     );
     GLSLC(1,     DTYPE a;                                                        );
@@ -460,8 +461,8 @@ static av_cold int init_weights_pipeline(FFVulkanContext *vkctx, FFVkExecPool *e
     GLSLC(1,         w_sum = w[0] + w[1] + w[2] + w[3];                          );
     GLSLC(1,         sum = dot(w, src * 255);                                    );
     GLSLC(0,                                                                     );
-    GLSLC(1,         weights[ws_off + pos.x] += w_sum;                           );
-    GLSLC(1,         sums[ws_off + pos.x] += sum;                                );
+    GLSLC(1,         weights[ws_off] += w_sum;                                   );
+    GLSLC(1,         sums[ws_off] += sum;                                        );
     GLSLC(0, }                                                                   );
 
     RET(spv->compile_shader(vkctx, spv, shd, &spv_data, &spv_len, "main", &spv_opaque));
@@ -634,7 +635,7 @@ static av_cold int init_filter(AVFilterContext *ctx)
     }
 
     for (int i = 0; i < 4; i++) {
-        double str = !isnan(s->opts.sc[i]) ? s->opts.sc[i] : s->opts.s;
+        double str = s->opts.sc[i] != -1.0 ? s->opts.sc[i] : s->opts.s;
         int ps = (s->opts.pc[i] ? s->opts.pc[i] : s->opts.p);
         str  = 10.0f*str;
         str *= -str;
@@ -1177,10 +1178,10 @@ static const AVOption nlmeans_vulkan_options[] = {
     { "r",  "research window radius", OFFSET(opts.r), AV_OPT_TYPE_INT, { .i64 = 7*2+1 }, 0, 99, FLAGS },
     { "t",  "parallelism", OFFSET(opts.t), AV_OPT_TYPE_INT, { .i64 = 8 }, 1, 64, FLAGS },
 
-    { "s1", "denoising strength for component 1", OFFSET(opts.sc[0]), AV_OPT_TYPE_DOUBLE, { .dbl = NAN }, 0.0, 100.0, FLAGS },
-    { "s2", "denoising strength for component 2", OFFSET(opts.sc[1]), AV_OPT_TYPE_DOUBLE, { .dbl = NAN }, 0.0, 100.0, FLAGS },
-    { "s3", "denoising strength for component 3", OFFSET(opts.sc[2]), AV_OPT_TYPE_DOUBLE, { .dbl = NAN }, 0.0, 100.0, FLAGS },
-    { "s4", "denoising strength for component 4", OFFSET(opts.sc[3]), AV_OPT_TYPE_DOUBLE, { .dbl = NAN }, 0.0, 100.0, FLAGS },
+    { "s1", "denoising strength for component 1", OFFSET(opts.sc[0]), AV_OPT_TYPE_DOUBLE, { .dbl = -1.0 }, 0.0, 100.0, FLAGS },
+    { "s2", "denoising strength for component 2", OFFSET(opts.sc[1]), AV_OPT_TYPE_DOUBLE, { .dbl = -1.0 }, 0.0, 100.0, FLAGS },
+    { "s3", "denoising strength for component 3", OFFSET(opts.sc[2]), AV_OPT_TYPE_DOUBLE, { .dbl = -1.0 }, 0.0, 100.0, FLAGS },
+    { "s4", "denoising strength for component 4", OFFSET(opts.sc[3]), AV_OPT_TYPE_DOUBLE, { .dbl = -1.0 }, 0.0, 100.0, FLAGS },
 
     { "p1", "patch size for component 1", OFFSET(opts.pc[0]), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS },
     { "p2", "patch size for component 2", OFFSET(opts.pc[1]), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 99, FLAGS },