From 2c8cfdebded263cfc5af4e4f33086b00fb543d33 Mon Sep 17 00:00:00 2001
From: Alexander Smorkalov <alexander.smorkalov@opencv.ai>
Date: Tue, 2 Dec 2025 10:40:01 +0300
Subject: [PATCH] Added RISC-V RVV diagnostics for PNG.

---
 3rdparty/libpng/CMakeLists.txt | 2 +-
 CMakeLists.txt                 | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/3rdparty/libpng/CMakeLists.txt b/3rdparty/libpng/CMakeLists.txt
index 8e4e585589..00366036df 100644
--- a/3rdparty/libpng/CMakeLists.txt
+++ b/3rdparty/libpng/CMakeLists.txt
@@ -186,7 +186,7 @@ endif()
 if(PNG_TARGET_ARCHITECTURE MATCHES "^(riscv)")
   include(CheckCCompilerFlag)
   set(PNG_RISCV_RVV_POSSIBLE_VALUES on off)
-  set(PNG_RISCV_RVV "off"
+  set(PNG_RISCV_RVV "on"
     CACHE STRING "Enable RISC-V Vector optimizations: on|off; off is default")
   set_property(CACHE PNG_RISCV_RVV
               PROPERTY STRINGS ${PNG_RISCV_RVV_POSSIBLE_VALUES})
diff --git a/CMakeLists.txt b/CMakeLists.txt
index de41a85379..f71fe9be11 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1557,6 +1557,8 @@ elseif(WITH_PNG OR HAVE_PNG)
     endif()
   elseif(PNG_LOONGARCH_LSX)
     status("      SIMD Support:" "YES (LoongArch LSX)")
+  elseif(PNG_RISCV_RVV)
+    status("      SIMD Support:" "YES (RISC-V RVV)")
   else()
     status("      SIMD Support:" "NO")
   endif()