From 69d38b02e54359d6b751b0fb941f47e6c6e220d7 Mon Sep 17 00:00:00 2001
From: Georgi Kostov <p_e_a@gbg.bg>
Date: Thu, 27 Nov 2025 22:53:23 +0200
Subject: [PATCH] Exposed the camera clock setting

---
 examples/AsyncCam/handlers.cpp |  3 +++
 src/esp32cam/config.cpp        | 12 ++++++++++++
 src/esp32cam/config.hpp        |  3 +++
 3 files changed, 18 insertions(+)

diff --git a/examples/AsyncCam/handlers.cpp b/examples/AsyncCam/handlers.cpp
index 69fda3c..243cb94 100644
--- a/examples/AsyncCam/handlers.cpp
+++ b/examples/AsyncCam/handlers.cpp
@@ -18,6 +18,7 @@ static const char FRONTPAGE[] = R"EOT(
 %vflip%
 %rawGma%
 %lensCorrection%
+%xclk%
 <input type="submit" value="update">
 </p></form>
 <p id="controls">
@@ -138,6 +139,7 @@ rewriteFrontpage(const esp32cam::Settings& s, const String& var) {
   SHOW_INT(brightness, -2, 2)
   SHOW_INT(contrast, -2, 2)
   SHOW_INT(saturation, -2, 2)
+  SHOW_INT(xclk, 6, 24)
   SHOW_BOOL(hmirror)
   SHOW_BOOL(vflip)
   SHOW_BOOL(rawGma)
@@ -166,6 +168,7 @@ handleUpdate(AsyncWebServerRequest* req) {
     SAVE_INT(gain);
     SAVE_INT(lightMode);
     SAVE_INT(specialEffect);
+	SAVE_INT(xclk);
     SAVE_BOOL(hmirror);
     SAVE_BOOL(vflip);
     SAVE_BOOL(rawGma);
diff --git a/src/esp32cam/config.cpp b/src/esp32cam/config.cpp
index f7c864f..22c6146 100644
--- a/src/esp32cam/config.cpp
+++ b/src/esp32cam/config.cpp
@@ -112,6 +112,7 @@ CameraClass::status() const {
   result.vflip = ss.vflip != 0;
   result.rawGma = ss.raw_gma != 0;
   result.lensCorrection = ss.lenc != 0;
+  result.xclk = sensor->xclk_freq_hz / 1000000U;
   return result;
 }
 
@@ -155,6 +156,7 @@ CameraClass::update(const Settings& settings, int sleepFor) {
   CHECK_RANGE(lightMode, -1, 4);
   CHECK_RANGE(specialEffect, 0, 6);
   CHECK_RANGE(gain, -128, 31);
+  CHECK_RANGE(xclk, 6, 24);
 
   UPDATE3(framesize, settings.resolution.as<framesize_t>(), framesize_t);
   UPDATE1(brightness);
@@ -184,6 +186,16 @@ CameraClass::update(const Settings& settings, int sleepFor) {
     UPDATE2(wb_mode, settings.lightMode);
   }
 
+  int prev = sensor->xclk_freq_hz / 1000000U, desired = settings.xclk;
+  if (prev != desired) {
+    int res = sensor->set_xclk(sensor, LEDC_TIMER_0, desired);
+    ESP32CAM_LOG("update xclk %d => %d %s", prev, desired,
+                 res == 0 ? "success" : "failure");
+    if (res != 0) {
+      return false;
+    }
+  }
+
 #undef CHECK_RANGE
 #undef UPDATE4
 #undef UPDATE3
diff --git a/src/esp32cam/config.hpp b/src/esp32cam/config.hpp
index 77f7e2b..2dabf41 100644
--- a/src/esp32cam/config.hpp
+++ b/src/esp32cam/config.hpp
@@ -94,6 +94,9 @@ struct Settings {
    * - AGC enabled: -2,-4,-8,-16,-32,-64,-128, which corresponds to 2x ~ 128x gain.
    */
   int8_t gain;
+  
+  /** @brief Camera clock value in MHz. Recommended to be between 6 and 24. */
+  int8_t xclk;
 
   /** @brief Image light mode. */
   LightMode lightMode;