docs: update multi-camera synchronization guidance

docs/en/source/camera_devices/5_advanced_guide/multi_camera/multi_camera.md

@@ -6,7 +6,6 @@
 ros2 run orbbec_camera list_devices_node
 ```
 
-- Set the `device_num` parameter to the number of cameras you have.
 - Go to the `OrbbecSDK_ROS2/orbbec_camera/launch/multi_xxx.launch.py` file and change the `usb_port`.
 - Don't forget to put the `include` tag inside the `group` tag.
   Otherwise, the parameter values of different cameras may become contaminated.
@@ -31,7 +30,6 @@ def generate_launch_description():
         launch_arguments={
             'camera_name': 'camera_01',
             'usb_port': '6-2.4.4.2',  # replace your usb port here
-            'device_num': '2'
         }.items()
     )
 
@@ -42,11 +40,10 @@ def generate_launch_description():
         launch_arguments={
             'camera_name': 'camera_02',
             'usb_port': '6-2.4.1',  # replace your usb port here
-            'device_num': '2'
         }.items()
     )
 
-    # If you need more cameras, just add more launch_include here, and change the usb_port and device_num
+    # If you need more cameras, just add more launch_include here and change the usb_port
 
     # Launch description
     ld = LaunchDescription([

docs/en/source/camera_devices/5_advanced_guide/multi_camera/multi_camera_synced.md

@@ -27,13 +27,11 @@ Open multi_camera_synced.launch.py, and configure the camera settings as shown b
 
 3. Set `usb_port` to `2-2`, indicating that the camera device on port `2-2` is being used. This value can be found in the output of the `ros2 run orbbec_camera list_devices_node` command.
 
-4. Set `device_num` to `2`, meaning two cameras will be used.
+4. Set `sync_mode` to `primary` to indicate that the `2-7` camera device is in primary mode. The multi-camera sync mode options can be found in the figure below.
 
-5. Set `sync_mode` to `primary` to indicate that the `2-7` camera device is in primary mode. The multi-camera sync mode options can be found in the figure below.
+5. Parameters from the `config_file_path` can override the parameters set in `gemini_330_series.launch.py` (optional).
 
-6. Parameters from the `config_file_path` can override the parameters set in `gemini_330_series.launch.py` (optional).
-
-7. For slave cameras, set `trigger_out_enabled` to false.
+6. For slave cameras, set `trigger_out_enabled` to false.
 
 | **Pattern Nam**e | **Setting effect description**                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
 | ---------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |

docs/en/source/camera_devices/5_advanced_guide/multi_camera/multi_camera_synced_verification_tool.md

@@ -2,8 +2,8 @@
 
 **File path:** [image_sync_example_node.cpp](https://github.com/orbbec/OrbbecSDK_ROS2/blob/v2-main/orbbec_camera/examples/multi_camera_time_sync/image_sync_example_node.cpp)
 
-This example node is designed for **synchronized capture and timestamp verification** across **four Orbbec cameras**.
-It can be used to validate frame alignment accuracy under the multi-camera **Primary / Secondary Synced** mode.
+This example node performs synchronized capture and timestamp verification across multiple Orbbec cameras and supports **1 to 8 image topics** at a time.
+At startup, it automatically discovers published color/depth image topics and can be used to validate frame alignment accuracy under the multi-camera **Primary / Secondary Synced** mode.
 
 ---
 
@@ -11,7 +11,7 @@ It can be used to validate frame alignment accuracy under the multi-camera **Pri
 
 ### **Modify `multi_camera_synced.launch.py` as follows**
 
-   - Add `launch_include` to support four cameras.
+   - Adjust `launch_include` according to the number of cameras participating in synchronization.
 
    - Select the appropriate launch file based on your camera model.
      For example, use `gemini_330_series.launch.py` for the Gemini 330 series.
@@ -19,8 +19,6 @@ It can be used to validate frame alignment accuracy under the multi-camera **Pri
    - Naming convention:
      `camera_name` should follow the format `camera_01`, `camera_02`, `camera_03`, ...
 
-   - Set `device_num` to **4**.
-
    - Configure the USB ports using:
 
      `ros2 run orbbec_camera list_devices_node`
@@ -61,11 +59,11 @@ It can be used to validate frame alignment accuracy under the multi-camera **Pri
 
      `ros2 run orbbec_camera image_sync_example_node`
 
-     This node outputs timestamp differences between multiple camera streams for synchronization validation.
+     The node automatically discovers color/depth image topics from the running cameras, displays synchronized images, and outputs timestamp differences and FPS statistics for synchronization validation.
 
 ---
 
-### **Reference Launch File**
+### **Four-Camera Reference Launch File**
 
 ```
 import os
@@ -93,7 +91,6 @@ def generate_launch_description():
         launch_arguments={
             "camera_name": "camera_01",
             "usb_port": "2-2.3",
-            "device_num": "4",
             "sync_mode": "primary",
             "config_file_path": config_file_path,
             "trigger_out_enabled": "true"
@@ -107,7 +104,6 @@ def generate_launch_description():
         launch_arguments={
             "camera_name": "camera_02",
             "usb_port": "2-1",
-            "device_num": "4",
             "sync_mode": "secondary_synced",
             "config_file_path": secondary_config_file_path,
             "trigger_out_enabled": "false"
@@ -121,7 +117,6 @@ def generate_launch_description():
         launch_arguments={
             "camera_name": "camera_03",
             "usb_port": "2-3",
-            "device_num": "4",
             "sync_mode": "secondary_synced",
             "config_file_path": secondary_config_file_path,
             "trigger_out_enabled": "false"
@@ -135,7 +130,6 @@ def generate_launch_description():
         launch_arguments={
             "camera_name": "camera_04",
             "usb_port": "2-4",
-            "device_num": "4",
             "sync_mode": "secondary_synced",
             "config_file_path": secondary_config_file_path,
             "trigger_out_enabled": "false"