From f9d16f29cfbbca6479af110a1cecb5094851394a Mon Sep 17 00:00:00 2001
From: Barzan Hayati <barzanhayati@gmail.com>
Date: Mon, 30 Jun 2025 00:09:24 +0000
Subject: [PATCH] Create streammux class

---
 CMakeLists.txt            |  7 +++++--
 data/configuration.json   |  4 ++++
 src/main.cpp              |  1 +
 src/pipeline_manager.cpp  |  4 ++++
 src/pipeline_manager.hpp  |  4 ++++
 src/streammux_manager.cpp | 37 +++++++++++++++++++++++++++++++++++++
 src/streammux_manager.hpp | 19 +++++++++++++++++++
 7 files changed, 74 insertions(+), 2 deletions(-)
 create mode 100644 data/configuration.json
 create mode 100644 src/streammux_manager.cpp
 create mode 100644 src/streammux_manager.hpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 12e0cb6..ac403f3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,16 +25,19 @@ endif()
 
 
 find_package(PkgConfig REQUIRED)
-pkg_check_modules(GLIB REQUIRED glib-2.0 gobject-2.0)
+pkg_check_modules(GLIB REQUIRED glib-2.0 gobject-2.0 nlohmann_json gstreamer-base-1.0 gstreamer-1.0 gstreamer-video-1.0)
 
 
 
 include_directories(/usr/lib/x86_64-linux-gnu/glib-2.0/include)
 include_directories(/usr/include/gstreamer-1.0)
+include_directories(/usr/include/nlohmann)
 include_directories(${PROJECT_SOURCE_DIR}/camera_manager.hpp)
 include_directories(${PROJECT_SOURCE_DIR}/pipeline_manager.hpp)
+include_directories(${PROJECT_SOURCE_DIR}/streammux_manager.hpp)
 
-set(SOURCES src/main.cpp  src/camera_manager.cpp src/pipeline_manager.cpp)
+
+set(SOURCES src/main.cpp  src/camera_manager.cpp src/pipeline_manager.cpp src/streammux_manager.cpp)
 # Create the executable
 add_executable(${PROJECT_NAME}  ${SOURCES})
 
diff --git a/data/configuration.json b/data/configuration.json
new file mode 100644
index 0000000..9a15f28
--- /dev/null
+++ b/data/configuration.json
@@ -0,0 +1,4 @@
+{
+    "MUXER_OUTPUT_HEIGHT": 1080,
+    "MUXER_OUTPUT_WIDTH": 1920
+}
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 36689ea..60e055d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -77,6 +77,7 @@ int main(int argc, char *argv[]) {
     PipelineManager *pipeline_manager =
         new PipelineManager(num_sources, url_camera);
     pipeline_manager->create_pipeline();
+    pipeline_manager->create_pipeline_elements(num_sources);
 
     return 0;
 }
\ No newline at end of file
diff --git a/src/pipeline_manager.cpp b/src/pipeline_manager.cpp
index 4a5fa60..6bfe606 100644
--- a/src/pipeline_manager.cpp
+++ b/src/pipeline_manager.cpp
@@ -20,4 +20,8 @@ int PipelineManager::create_pipeline() {
         return -1;
     }
     return 1;
+}
+
+void PipelineManager::create_pipeline_elements(int num_sources) {
+    streammux_manager->create_streammux(num_sources);
 }
\ No newline at end of file
diff --git a/src/pipeline_manager.hpp b/src/pipeline_manager.hpp
index 8d9ab8c..603efe6 100644
--- a/src/pipeline_manager.hpp
+++ b/src/pipeline_manager.hpp
@@ -1,16 +1,20 @@
 #include <glib.h>
 #include <gst/gst.h>
 
+#include "streammux_manager.hpp"
+
 class PipelineManager {
    private:
     gboolean g_run_forever = FALSE;
     GMainLoop *loop = NULL;
     GstElement *pipeline = NULL;
     GMutex eos_lock;
+    StreammuxManager *streammux_manager = new StreammuxManager();
 
    public:
     PipelineManager();
     PipelineManager(int, char **);
     int create_pipeline();
+    void create_pipeline_elements(int);
     ~PipelineManager();
 };
\ No newline at end of file
diff --git a/src/streammux_manager.cpp b/src/streammux_manager.cpp
new file mode 100644
index 0000000..c9d9612
--- /dev/null
+++ b/src/streammux_manager.cpp
@@ -0,0 +1,37 @@
+#include "streammux_manager.hpp"
+
+#define SET_GPU_ID(object, gpu_id) \
+    g_object_set(G_OBJECT(object), "gpu-id", gpu_id, NULL);
+#define GPU_ID 0
+#define MUXER_BATCH_TIMEOUT_USEC 40000
+
+using json = nlohmann::json;
+
+StreammuxManager::StreammuxManager() {
+    json j;
+    std::ifstream i("../data/configuration.json");
+    i >> j;
+
+    MUXER_OUTPUT_HEIGHT = j["MUXER_OUTPUT_HEIGHT"];
+    MUXER_OUTPUT_WIDTH = j["MUXER_OUTPUT_WIDTH"];
+}
+
+bool StreammuxManager::create_streammux(int num_sources) {
+    /* Create nvstreammux instance to form batches from one or more sources. */
+    streammux = gst_element_factory_make("nvstreammux", "stream-muxer");
+    g_object_set(G_OBJECT(streammux), "batch-size", num_sources, NULL);
+    g_object_set(G_OBJECT(streammux), "enable-padding", 1, NULL);
+    //    g_object_set (G_OBJECT (streammux), "drop-pipeline-eos",
+    //    g_run_forever, NULL);
+    g_object_set(G_OBJECT(streammux), "live-source", 1, NULL);
+    g_object_set(G_OBJECT(streammux), "width", MUXER_OUTPUT_WIDTH, "height",
+                 MUXER_OUTPUT_HEIGHT, "batched-push-timeout",
+                 MUXER_BATCH_TIMEOUT_USEC, NULL);
+    SET_GPU_ID(streammux, GPU_ID);
+
+    if (!streammux) {
+        g_printerr("Unable to create streammux.Exiting.");
+        return false;
+    }
+    return true;
+}
\ No newline at end of file
diff --git a/src/streammux_manager.hpp b/src/streammux_manager.hpp
new file mode 100644
index 0000000..0ab6573
--- /dev/null
+++ b/src/streammux_manager.hpp
@@ -0,0 +1,19 @@
+#include <gst/gst.h>
+
+#include <fstream>
+#include <iostream>
+#include <nlohmann/json.hpp>
+
+#include "json.hpp"
+
+class StreammuxManager {
+   private:
+    GstElement *streammux = NULL;
+
+   public:
+    int MUXER_OUTPUT_WIDTH;
+    int MUXER_OUTPUT_HEIGHT;
+    StreammuxManager();
+    bool create_streammux(int);
+    ~StreammuxManager();
+};
\ No newline at end of file