diff --git a/video_encoder/lib/libtavenc/tav_encoder_lib.c b/video_encoder/lib/libtavenc/tav_encoder_lib.c
index bdfd445..77266ba 100644
--- a/video_encoder/lib/libtavenc/tav_encoder_lib.c
+++ b/video_encoder/lib/libtavenc/tav_encoder_lib.c
@@ -201,7 +201,7 @@ struct tav_encoder_context {
     int gop_size;
     int enable_two_pass;
     int quality_level;
-    int dead_zone_threshold;
+    float dead_zone_threshold;
     int entropy_coder;
     int zstd_level;
     int num_threads;
@@ -1213,20 +1213,20 @@ static int encode_gop_intra_only(tav_encoder_context_t *ctx, gop_slot_t *slot) {
         // Quantize
         if (ctx->perceptual_tuning) {
             tav_quantise_perceptual(ctx->compat_enc, frame_y, quant_y, num_pixels,
-                                   base_quantiser_y, (float)ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 0, 0);
+                                   base_quantiser_y, ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 0, 0);
             tav_quantise_perceptual(ctx->compat_enc, frame_co, quant_co, num_pixels,
-                                   base_quantiser_co, (float)ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 1, 0);
+                                   base_quantiser_co, ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 1, 0);
             tav_quantise_perceptual(ctx->compat_enc, frame_cg, quant_cg, num_pixels,
-                                   base_quantiser_cg, (float)ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 1, 0);
+                                   base_quantiser_cg, ctx->dead_zone_threshold, width, height, ctx->decomp_levels, 1, 0);
         } else {
             tav_quantise_uniform(frame_y, quant_y, num_pixels, base_quantiser_y,
-                                (float)ctx->dead_zone_threshold, width, height,
+                                ctx->dead_zone_threshold, width, height,
                                 ctx->decomp_levels, 0);
             tav_quantise_uniform(frame_co, quant_co, num_pixels, base_quantiser_co,
-                                (float)ctx->dead_zone_threshold, width, height,
+                                ctx->dead_zone_threshold, width, height,
                                 ctx->decomp_levels, 1);
             tav_quantise_uniform(frame_cg, quant_cg, num_pixels, base_quantiser_cg,
-                                (float)ctx->dead_zone_threshold, width, height,
+                                ctx->dead_zone_threshold, width, height,
                                 ctx->decomp_levels, 1);
         }
 
@@ -1276,28 +1276,28 @@ static int encode_gop_intra_only(tav_encoder_context_t *ctx, gop_slot_t *slot) {
                 // Quantize tile coefficients
                 if (ctx->perceptual_tuning) {
                     tav_quantise_perceptual(ctx->compat_enc, tile_y, quant_y, padded_pixels,
-                                           base_quantiser_y, (float)ctx->dead_zone_threshold,
+                                           base_quantiser_y, ctx->dead_zone_threshold,
                                            TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                            ctx->decomp_levels, 0, 0);
                     tav_quantise_perceptual(ctx->compat_enc, tile_co, quant_co, padded_pixels,
-                                           base_quantiser_co, (float)ctx->dead_zone_threshold,
+                                           base_quantiser_co, ctx->dead_zone_threshold,
                                            TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                            ctx->decomp_levels, 1, 0);
                     tav_quantise_perceptual(ctx->compat_enc, tile_cg, quant_cg, padded_pixels,
-                                           base_quantiser_cg, (float)ctx->dead_zone_threshold,
+                                           base_quantiser_cg, ctx->dead_zone_threshold,
                                            TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                            ctx->decomp_levels, 1, 0);
                 } else {
                     tav_quantise_uniform(tile_y, quant_y, padded_pixels, base_quantiser_y,
-                                        (float)ctx->dead_zone_threshold,
+                                        ctx->dead_zone_threshold,
                                         TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                         ctx->decomp_levels, 0);
                     tav_quantise_uniform(tile_co, quant_co, padded_pixels, base_quantiser_co,
-                                        (float)ctx->dead_zone_threshold,
+                                        ctx->dead_zone_threshold,
                                         TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                         ctx->decomp_levels, 1);
                     tav_quantise_uniform(tile_cg, quant_cg, padded_pixels, base_quantiser_cg,
-                                        (float)ctx->dead_zone_threshold,
+                                        ctx->dead_zone_threshold,
                                         TAV_PADDED_TILE_SIZE_X, TAV_PADDED_TILE_SIZE_Y,
                                         ctx->decomp_levels, 1);
                 }
diff --git a/video_encoder/src/encoder_tav.c b/video_encoder/src/encoder_tav.c
index 808d656..d6f18f5 100644
--- a/video_encoder/src/encoder_tav.c
+++ b/video_encoder/src/encoder_tav.c
@@ -306,8 +306,8 @@ static void print_usage(const char *program) {
     printf("  --zstd-level N           Zstd level 3-22 (default: 7)\n");
     printf("  --no-perceptual-tuning   Disable HVS perceptual quantization\n");
     printf("  --no-dead-zone           Disable dead-zone quantization\n");
-    printf("  --dead-zone-threshold N  Dead-zone threshold 1-10 (default: 0=disabled)\n");
-    printf("  Note: EZBC entropy coder is always used (Twobitmap deprecated)\n");
+    printf("  --dead-zone-threshold N  Dead-zone threshold. Defaults by quality level:\n");
+    printf("                           0=1.5, 1=1.5, 2=1.2, 3=1.1, 4=0.8, 5=0.6\n");
     printf("\nEncoder Presets:\n");
     printf("  --preset-sports          Sports mode (finer temporal quantization)\n");
     printf("  --preset-anime           Anime mode (disable grain)\n");
@@ -2394,7 +2394,7 @@ int main(int argc, char *argv[]) {
                 cli.enc_params.perceptual_tuning = 0;
                 break;
             case 1007:  // --no-dead-zone
-                cli.enc_params.dead_zone_threshold = 0;
+                cli.enc_params.dead_zone_threshold = 0.0;
                 break;
             case 1009:  // --encode-limit
                 cli.encode_limit = atoi(optarg);
@@ -2431,7 +2431,7 @@ int main(int argc, char *argv[]) {
                 cli.enc_params.temporal_wavelet = atoi(optarg);
                 break;
             case 1023:  // --dead-zone-threshold
-                cli.enc_params.dead_zone_threshold = atoi(optarg);
+                cli.enc_params.dead_zone_threshold = atof(optarg);
                 break;
             case 1024:  // --decomp-levels
                 cli.enc_params.decomp_levels = atoi(optarg);