From 1358c0ae66d4d63d1c27d1c9e06a49184d69fc33 Mon Sep 17 00:00:00 2001
From: Alexander Smorkalov <alexander.smorkalov@xperience.ai>
Date: Thu, 23 Jan 2020 08:59:01 +0300
Subject: [PATCH] Made automated triggering for ARAVIS cameras optional.

---
 modules/videoio/include/opencv2/videoio.hpp | 10 ++++++++++
 modules/videoio/src/cap_aravis.cpp          | 15 ++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/modules/videoio/include/opencv2/videoio.hpp b/modules/videoio/include/opencv2/videoio.hpp
index 5dd10fd268..d16a4cdd47 100644
--- a/modules/videoio/include/opencv2/videoio.hpp
+++ b/modules/videoio/include/opencv2/videoio.hpp
@@ -483,6 +483,16 @@ enum { CAP_PROP_XI_DOWNSAMPLING                                 = 400, //!< Chan
 
 //! @} XIMEA
 
+/** @name XIMEA Camera API
+*  @{
+*/
+
+//! Properties of cameras available through ARAVIS backend
+enum { CAP_PROP_ARAVIS_AUTOTRIGGER                              = 600 //!< Automatically trigger frame capture if camera is configured with software trigger
+};
+
+//! @} ARAVIS
+
 /** @name AVFoundation framework for iOS
     OS X Lion will have the same API
     @{
diff --git a/modules/videoio/src/cap_aravis.cpp b/modules/videoio/src/cap_aravis.cpp
index e1f00b4a03..c43389d53d 100644
--- a/modules/videoio/src/cap_aravis.cpp
+++ b/modules/videoio/src/cap_aravis.cpp
@@ -149,6 +149,7 @@ protected:
     bool            autoGain;
     double          targetGrey;             // Target grey value (mid grey))
     bool            softwareTriggered;      // Flag if the camera is software triggered
+    bool            allowAutoTrigger;       // Flag that user allowed to trigger software triggered cameras automatically
 
     gint64          *pixelFormats;
     guint           pixelFormatsCnt;
@@ -190,6 +191,7 @@ CvCaptureCAM_Aravis::CvCaptureCAM_Aravis()
     exposureCompensation = 0;
     targetGrey = 0;
     frameID = prevFrameID = 0;
+    allowAutoTrigger = false;
 
     num_buffers = 10;
     frame = NULL;
@@ -292,7 +294,7 @@ bool CvCaptureCAM_Aravis::grabFrame()
         ArvBuffer *arv_buffer = NULL;
         int max_tries = 10;
         int tries = 0;
-        if (softwareTriggered) {
+        if (softwareTriggered && allowAutoTrigger) {
             arv_camera_software_trigger (camera);
         }
         for(; tries < max_tries; tries ++) {
@@ -499,6 +501,12 @@ double CvCaptureCAM_Aravis::getProperty( int property_id ) const
                 return out;
             }
             break;
+
+        case CAP_PROP_ARAVIS_AUTOTRIGGER:
+        {
+            return allowAutoTrigger ? 1. : 0.;
+        }
+        break;
     }
     return -1.0;
 }
@@ -583,6 +591,11 @@ bool CvCaptureCAM_Aravis::setProperty( int property_id, double value )
             }
             break;
 
+        case CAP_PROP_ARAVIS_AUTOTRIGGER:
+            {
+                allowAutoTrigger = (bool) value;
+            }
+            break;
 
         default:
             return false;