diff --git a/Cargo.toml b/Cargo.toml
index cdada855..92550168 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -25,7 +25,7 @@ uriparse = {version = "0.6", optional = true}
 chrono = { version = "0.4", default-features = false, features = ["clock", "std", "oldtime"] }
 chrono-tz = {version = "0.10", optional = true}
 image = {version = "=0.25.8", optional = true, default-features = false}
-imageproc = {version = "0.25", optional = true}
+imageproc = {version = "0.25", optional = true, default-features = false}
 unicode-segmentation = "1.13"
 codepage-437 = {version = "0.1", optional = true}
 rxing-one-d-proc-derive = {version = "0.9", path ="./crates/one-d-proc-derive", optional = true}
@@ -46,6 +46,7 @@ default = [
     "image",
     "client_support",
     "image_formats",
+    "rayon",
     "serde",
     "encoding_rs",
     "encoders",
@@ -75,6 +76,10 @@ image_formats = [
     "image/ff",
 ]
 
+#/// Enable rayon-based parallelism inside imageproc operations (binarizers, filters).
+#/// Off by default; correctness is unaffected, this only speeds up image processing.
+rayon = ["image", "imageproc/rayon"]
+
 #/// Enable barcode encoders
 encoders = []
 
diff --git a/README.md b/README.md
index 6dce0cc5..3138ebd9 100644
--- a/README.md
+++ b/README.md
@@ -73,6 +73,7 @@ The following feature flags are available:
 ### Core & Engine
 * `image` (default): Enable features required for image manipulation and reading.
 * `image_formats` (default): Enabled by default. Compile all `image` crate image format support options.
+* `rayon` (default): Enabled by default. Turns on `rayon`-based parallelism inside the `imageproc` operations rxing uses (binarizers, filters).
 * `encoders` (default): Enable barcode encoders.
 * `decoders` (default): Enable barcode decoders.
 * `multi_barcode_readers` (default): Enable support for reading multiple barcodes in a single image.
@@ -106,6 +107,7 @@ default = [
     "image",
     "client_support",
     "image_formats",
+    "rayon",
     "serde",
     "encoding_rs",
     "encoders",