Add call to gst_ctf_close and ref counting

[dwalkes]

To avoid issues with empty files on exit of the pipeline, see
[1].

Note: This code only works if the pipleine gracefully exits,
including calling gst_deinit(). This probably means you
need to add a signal handler for SIGINT if your pipeline
doesn't exit normally.

1: #92
Signed-off-by: Dan Walkes [email protected]

[dwalkes]

Thanks for sharing this useful tool!

This change works for me to resolve #92 as tested with a modified version of the deepstream-test1 sample application on tegra.

One requirement is to ensure your pipeline exits gracefully and calls gst_deinit(). Here's an example patch for deepstream-test1 application which includes this.

Author: Dan Walkes <[email protected]>                                                                                      
Date:   Thu Jun 9 23:06:00 2022 -0600                                                                                                 
                                                                                                                                      
    Add signal handler for sigint                                                                                                     
                                                                                                                                      
    This is a requirement to play nicely with gst-shark                                                                               
                                                                                                                                      
diff --git a/apps/sample_apps/deepstream-test1/deepstream_test1_app.c b/apps/sample_apps/deepstream-test1/deepstream_test1_app.c      
index 150b58c..2087367 100644                                                                                                         
--- a/apps/sample_apps/deepstream-test1/deepstream_test1_app.c                                                                        
+++ b/apps/sample_apps/deepstream-test1/deepstream_test1_app.c                                                                        
@@ -27,6 +27,7 @@ gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,format=YUY2,width=1280,h                                    
 #include <glib.h>                                                                                                                    
 #include <stdio.h>                                                                                                                   
 #include "gstnvdsmeta.h"                                                                                                             
+#include <glib-unix.h>                                                                                                               
                                                                                                                                      
 #define MAX_DISPLAY_LEN 64                                                                                                           
                                                                                                                                      
@@ -142,12 +143,36 @@ bus_call (GstBus * bus, GstMessage * msg, gpointer data)                                                        
       g_main_loop_quit (loop);                                                                                                       
       break;                                                                                                                         
     }                                                                                                                                
+    case GST_MESSAGE_APPLICATION:{                                                                                                   
+      const GstStructure *s;                                                                                                         
+      s = gst_message_get_structure (msg);                                                                                           
+      if (gst_structure_has_name (s, "GstLaunchInterrupt")) {                                                                        
+        /* this application message is posted when we caught an interrupt and                                                        
+          * we need to stop the pipeline. */                                                                                         
+        g_print ("Interrupt: Stopping pipeline ...\n");                                                                              
+        g_main_loop_quit (loop);                                                                                                     
+      }                                                                                                                              
+      break;                                                                                                                         
+    }                                                                                                                                
     default:                                                                                                                         
       break;                                                                                                                         
   }                                                                                                                                  
   return TRUE;                                                                                                                       
 }                                                                                                                                    
                                                                                                                                      
+static gboolean                                                                                                                      
+intr_handler (gpointer user_data)                                                                                                    
+{                                                                                                                                    
+  GstElement *pipeline = (GstElement *) user_data;                                                                                   
+  g_print ("handling interrupt.\n");                                                                                                 
+  gst_element_post_message (GST_ELEMENT (pipeline),                                                                                  
+       gst_message_new_application (GST_OBJECT (pipeline),                                                                           
+        gst_structure_new ("GstLaunchInterrupt",                                                                                     
+            "message", G_TYPE_STRING, "Pipeline interrupted", NULL)));                                                               
+  return G_SOURCE_REMOVE;                                                                                                            
+}                                                                                                                                    
+                                                                                                                                     
+                                                                                                                                     
 int                                                                                                                                  
 main (int argc, char *argv[])                                                                                                        
 {                                                                                                                                    
@@ -172,6 +197,7 @@ main (int argc, char *argv[])
   /* Create gstreamer elements */
   /* Create Pipeline element that will form a connection of other elements */
   pipeline = gst_pipeline_new ("dstest1-pipeline");
+  g_unix_signal_add (SIGINT, (GSourceFunc) intr_handler, pipeline);

   /* Source element for reading from the file */
   source = gst_element_factory_make ("v4l2src", "v4l2-source");
@@ -301,5 +327,6 @@ main (int argc, char *argv[])
   gst_object_unref (GST_OBJECT (pipeline));
   g_source_remove (bus_watch_id);
   g_main_loop_unref (loop);
+  gst_deinit();
   return 0;
 }

[michaelgruner]

Thanks for the suggestion, I think it is a clever alternative to depending on gst_deinit