diff --git a/build_source.sh b/build_source.sh
index e1fe5fba..61335ef3 100755
--- a/build_source.sh
+++ b/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/alpine320/build_source.sh b/docker-images/8.0/alpine320/build_source.sh
index 217191a3..1784cb73 100755
--- a/docker-images/8.0/alpine320/build_source.sh
+++ b/docker-images/8.0/alpine320/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/nvidia2404/build_source.sh b/docker-images/8.0/nvidia2404/build_source.sh
index 3816785f..b395c9d2 100755
--- a/docker-images/8.0/nvidia2404/build_source.sh
+++ b/docker-images/8.0/nvidia2404/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/scratch320/build_source.sh b/docker-images/8.0/scratch320/build_source.sh
index 217191a3..1784cb73 100755
--- a/docker-images/8.0/scratch320/build_source.sh
+++ b/docker-images/8.0/scratch320/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/ubuntu2404-edge/build_source.sh b/docker-images/8.0/ubuntu2404-edge/build_source.sh
index 217191a3..1784cb73 100755
--- a/docker-images/8.0/ubuntu2404-edge/build_source.sh
+++ b/docker-images/8.0/ubuntu2404-edge/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/ubuntu2404/build_source.sh b/docker-images/8.0/ubuntu2404/build_source.sh
index 217191a3..1784cb73 100755
--- a/docker-images/8.0/ubuntu2404/build_source.sh
+++ b/docker-images/8.0/ubuntu2404/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install
diff --git a/docker-images/8.0/vaapi2404/build_source.sh b/docker-images/8.0/vaapi2404/build_source.sh
index 53f0bcdd..070d5cf2 100755
--- a/docker-images/8.0/vaapi2404/build_source.sh
+++ b/docker-images/8.0/vaapi2404/build_source.sh
@@ -33,7 +33,7 @@ build_libx264() {
 
 build_libx265() {
     cd build/linux
-    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX}/" multilib.sh
+    sed -i "/-DEXTRA_LIB/ s/$/ -DCMAKE_INSTALL_PREFIX=\${PREFIX} -DENABLE_ALPHA=ON/" multilib.sh
     sed -i "/^cmake/ s/$/ -DENABLE_CLI=OFF/" multilib.sh
     ./multilib.sh
     make -C 8bit install