diff --git a/hgdriver/hgdev/hg_scanner.cpp b/hgdriver/hgdev/hg_scanner.cpp
index 1ef0596..92324d4 100644
--- a/hgdriver/hgdev/hg_scanner.cpp
+++ b/hgdriver/hgdev/hg_scanner.cpp
@@ -24,11 +24,14 @@ hg_scanner::hg_scanner(ScannerSerial serial
 					, notify_setting_result_(false), user_cancel_(false), cb_mem_(true), test_1_paper_(false)
 					, setting_count_(0),img_type_(""), online_(false)
 {
+	custom_gamma_val_ = new SANE_Gamma;
+	memset(custom_gamma_val_, 0, sizeof(SANE_Gamma));
+
 	paper_size_mm_.cx = 210;
 	paper_size_mm_.cy = 297;
-	custom_gamma_val_.pt_count_r = custom_gamma_val_.pt_count_g = custom_gamma_val_.pt_count_b = 0;
-	for (int i = 0; i < ARRAY_SIZE(custom_gamma_val_.table); ++i)
-		custom_gamma_val_.table[i] = i & 0x0ff;
+	custom_gamma_val_->pt_count_r = custom_gamma_val_->pt_count_g = custom_gamma_val_->pt_count_b = 0;
+	for (int i = 0; i < ARRAY_SIZE(custom_gamma_val_->table); ++i)
+		custom_gamma_val_->table[i] = i & 0x0ff;
 
 	HG_VLOG_MINI_2(HG_LOG_LEVEL_DEBUG_INFO, "%s(%s) constructed\n", name_.c_str(), hg_log::format_ptr(this).c_str());
 	image_prc_param_.value = 0;
@@ -53,6 +56,7 @@ hg_scanner::~hg_scanner()
 		thread_usb_read_->join();
 	if (thread_img_handle_.get() && thread_img_handle_->joinable())
 		thread_img_handle_->join();
+	delete custom_gamma_val_;
 
 	name_.insert(0, "\350\256\276\345\244\207 “");
 	name_ += "”\345\267\262\347\273\217\345\205\263\351\227\255\343\200\202";
@@ -455,9 +459,9 @@ int hg_scanner::restore(int setting_no)
 	setting_jsn_.at(key).at("name").get_to(val);
 	if (val == KNOWN_OPT_NAME_CUSTOM_GAMMA)
 	{
-		custom_gamma_val_.pt_count_r = custom_gamma_val_.pt_count_g = custom_gamma_val_.pt_count_b = 0;
-		for (int i = 0; i < ARRAY_SIZE(custom_gamma_val_.table); ++i)
-			custom_gamma_val_.table[i] = i & 0x0ff;
+		custom_gamma_val_->pt_count_r = custom_gamma_val_->pt_count_g = custom_gamma_val_->pt_count_b = 0;
+		for (int i = 0; i < ARRAY_SIZE(custom_gamma_val_->table); ++i)
+			custom_gamma_val_->table[i] = i & 0x0ff;
 
 		return HG_ERR_OK;
 	}
@@ -1357,7 +1361,7 @@ int hg_scanner::setting_custom_gamma_data(void* data)
 {
 	SANE_Gamma* gamma = (SANE_Gamma*)data;
 
-	memcpy(&custom_gamma_val_, gamma, sizeof(custom_gamma_val_));
+	memcpy(custom_gamma_val_, gamma, sizeof(*custom_gamma_val_));
 
 	return HG_ERR_OK;
 }
@@ -1899,11 +1903,11 @@ int hg_scanner::get_setting(int setting_no, char* json_txt_buf, int* len)
 	{
 		name = "";
 		add = 3 * 256;
-		sprintf(sn, "[%u", custom_gamma_val_.table[0]);
+		sprintf(sn, "[%u", custom_gamma_val_->table[0]);
 		name += sn;
 		for (int i = 1; i < add; ++i)
 		{
-			sprintf(sn, ",%u", custom_gamma_val_.table[i]);
+			sprintf(sn, ",%u", custom_gamma_val_->table[i]);
 			name += sn;
 		}
 		name += "]";
@@ -2188,7 +2192,7 @@ int hg_scanner::device_io_control(unsigned long code, void* data, unsigned* len)
 	{
 		SANE_Gamma* v = (SANE_Gamma*)data;
 
-		memcpy(v, &custom_gamma_val_, sizeof(custom_gamma_val_));
+		memcpy(v, custom_gamma_val_, sizeof(*custom_gamma_val_));
 
 		return HG_ERR_OK;
 	}
@@ -2196,7 +2200,7 @@ int hg_scanner::device_io_control(unsigned long code, void* data, unsigned* len)
 	{
 		SANE_Gamma* v = (SANE_Gamma*)data;
 
-		memcpy(&custom_gamma_val_, v, sizeof(custom_gamma_val_));
+		memcpy(custom_gamma_val_, v, sizeof(*custom_gamma_val_));
 
 		return HG_ERR_OK;
 	}
diff --git a/hgdriver/hgdev/hg_scanner.h b/hgdriver/hgdev/hg_scanner.h
index f5fad5f..45adf91 100644
--- a/hgdriver/hgdev/hg_scanner.h
+++ b/hgdriver/hgdev/hg_scanner.h
@@ -253,7 +253,7 @@ protected:
     ////////////////////////////////////////////////////////////////
     // 新增自定义伽玛曲线及扫描区域属性 - 2022-05-05
     bool    custom_gamma_;                  // 为true时，应用custom_gamma_val_阵列调整图像色彩；为false时，保持原来的处理方式
-    SANE_Gamma custom_gamma_val_;           // 当为RGB或者彩色时，为三组256字节的数据；当为黑白或灰度时，只有一组256字节
+    SANE_Gamma *custom_gamma_val_;          // 当为RGB或者彩色时，为三组256字节的数据；当为黑白或灰度时，只有一组256字节
     bool    custom_area_;                   // 是否启用自定义区域，为true时才使用下列4个数据；为false时保持原来的处理方式
     double  custom_area_lt_x_;              // 自定义区域左上角x坐标
     double  custom_area_lt_y_;              // 自定义区域左上角y坐标