diff --git a/ports/opencv3/0012-fix-zlib.patch b/ports/opencv3/0012-fix-zlib.patch
new file mode 100644
index 0000000000..7f01dabf3c
--- /dev/null
+++ b/ports/opencv3/0012-fix-zlib.patch
@@ -0,0 +1,14 @@
+diff --git a/cmake/OpenCVFindLibsGrfmt.cmake b/cmake/OpenCVFindLibsGrfmt.cmake
+index 6dbeca9..08e2f4a 100644
+--- a/cmake/OpenCVFindLibsGrfmt.cmake
++++ b/cmake/OpenCVFindLibsGrfmt.cmake
+@@ -5,6 +5,9 @@
+ # --- zlib (required) ---
+ if(BUILD_ZLIB)
+   ocv_clear_vars(ZLIB_FOUND)
++elseif(1)
++  ocv_clear_internal_cache_vars(ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
++  find_package(ZLIB "${MIN_VER_ZLIB}" REQUIRED)
+ else()
+   ocv_clear_internal_cache_vars(ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
+   if(ANDROID)
diff --git a/ports/opencv3/portfile.cmake b/ports/opencv3/portfile.cmake
index f1b4315b7c..7f8b548380 100644
--- a/ports/opencv3/portfile.cmake
+++ b/ports/opencv3/portfile.cmake
@@ -26,6 +26,7 @@ vcpkg_from_github(
       0009-fix-protobuf.patch
       0010-fix-uwp-tiff-imgcodecs.patch
       0011-remove-python2.patch
+      0012-fix-zlib.patch
 )
 
 if(VCPKG_TARGET_ARCHITECTURE STREQUAL "arm64")
diff --git a/ports/opencv3/vcpkg.json b/ports/opencv3/vcpkg.json
index 804084d71d..530cc0ca7e 100644
--- a/ports/opencv3/vcpkg.json
+++ b/ports/opencv3/vcpkg.json
@@ -1,7 +1,7 @@
 {
   "name": "opencv3",
   "version": "3.4.16",
-  "port-version": 2,
+  "port-version": 3,
   "description": "computer vision library",
   "homepage": "https://github.com/opencv/opencv",
   "license": "BSD-3-Clause",
diff --git a/ports/opencv4/0012-fix-zlib.patch b/ports/opencv4/0012-fix-zlib.patch
new file mode 100644
index 0000000000..9c38fd8925
--- /dev/null
+++ b/ports/opencv4/0012-fix-zlib.patch
@@ -0,0 +1,14 @@
+diff --git a/cmake/OpenCVFindLibsGrfmt.cmake b/cmake/OpenCVFindLibsGrfmt.cmake
+index 8ea5497..7ed3f6b 100644
+--- a/cmake/OpenCVFindLibsGrfmt.cmake
++++ b/cmake/OpenCVFindLibsGrfmt.cmake
+@@ -5,6 +5,9 @@
+ # --- zlib (required) ---
+ if(BUILD_ZLIB)
+   ocv_clear_vars(ZLIB_FOUND)
++elseif(1)
++  ocv_clear_internal_cache_vars(ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
++  find_package(ZLIB "${MIN_VER_ZLIB}" REQUIRED)
+ else()
+   ocv_clear_internal_cache_vars(ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
+   if(ANDROID)
diff --git a/ports/opencv4/portfile.cmake b/ports/opencv4/portfile.cmake
index 500038ff06..71c805b76d 100644
--- a/ports/opencv4/portfile.cmake
+++ b/ports/opencv4/portfile.cmake
@@ -26,6 +26,7 @@ vcpkg_from_github(
       0009-fix-protobuf.patch
       0010-fix-uwp-tiff-imgcodecs.patch
       0011-remove-python2.patch
+      0012-fix-zlib.patch
 )
 
 if(VCPKG_TARGET_ARCHITECTURE STREQUAL "arm64")
diff --git a/ports/opencv4/vcpkg.json b/ports/opencv4/vcpkg.json
index 763c219e8d..ffdd95f97f 100644
--- a/ports/opencv4/vcpkg.json
+++ b/ports/opencv4/vcpkg.json
@@ -1,7 +1,7 @@
 {
   "name": "opencv4",
   "version": "4.5.4",
-  "port-version": 3,
+  "port-version": 4,
   "description": "computer vision library",
   "homepage": "https://github.com/opencv/opencv",
   "dependencies": [
diff --git a/versions/baseline.json b/versions/baseline.json
index c8b5e0096a..0edbad27e2 100644
--- a/versions/baseline.json
+++ b/versions/baseline.json
@@ -5002,11 +5002,11 @@
     },
     "opencv3": {
       "baseline": "3.4.16",
-      "port-version": 2
+      "port-version": 3
     },
     "opencv4": {
       "baseline": "4.5.4",
-      "port-version": 3
+      "port-version": 4
     },
     "opendnp3": {
       "baseline": "3.1.1",
diff --git a/versions/o-/opencv3.json b/versions/o-/opencv3.json
index 98617f1fd0..167793486c 100644
--- a/versions/o-/opencv3.json
+++ b/versions/o-/opencv3.json
@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "76d605b750c5535590489574dc24fa30ffe249f8",
+      "version": "3.4.16",
+      "port-version": 3
+    },
     {
       "git-tree": "a11dd583ecb7212732fedb0ab3e3308ea84f10d9",
       "version": "3.4.16",
diff --git a/versions/o-/opencv4.json b/versions/o-/opencv4.json
index 2add172495..ee29cc212f 100644
--- a/versions/o-/opencv4.json
+++ b/versions/o-/opencv4.json
@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "ce474a40e6572ced8dd1229f22f6cbed9cc74212",
+      "version": "4.5.4",
+      "port-version": 4
+    },
     {
       "git-tree": "b170a087d34521462cd247a24f230627a272975e",
       "version": "4.5.4",