diff --git a/include/OpenMPUtilities.h b/include/OpenMPUtilities.h
index 9810d636..5b5107c1 100644
--- a/include/OpenMPUtilities.h
+++ b/include/OpenMPUtilities.h
@@ -41,5 +41,12 @@
 #define OPEN_MP_NUM_PROCESSORS (std::min(omp_get_num_procs(), std::max(2, openshot::Settings::Instance()->OMP_THREADS) ))
 #define FF_NUM_PROCESSORS (std::min(omp_get_num_procs(), std::max(2, openshot::Settings::Instance()->FF_THREADS) ))
 
+// Set max-active-levels to the max supported, if possible
+// (supported_active_levels is OpenMP 5.0 (November 2018) or later, only.)
+#if (_OPENMP >= 201811)
+  #define OPEN_MP_MAX_ACTIVE openmp_get_supported_active_levels()
+#else
+  #define OPEN_MP_MAX_ACTIVE OPEN_MP_NUM_PROCESSORS
+#endif
 
 #endif
diff --git a/src/FFmpegReader.cpp b/src/FFmpegReader.cpp
index 12b9776a..fea4f60b 100644
--- a/src/FFmpegReader.cpp
+++ b/src/FFmpegReader.cpp
@@ -91,6 +91,11 @@ FFmpegReader::FFmpegReader(const std::string& path, bool inspect_reader)
 		  current_video_frame(0), has_missing_frames(false), num_packets_since_video_frame(0), num_checks_since_final(0),
 		  packet(NULL) {
 
+	// Configure OpenMP parallelism
+	// Default number of threads per section
+	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
+	// Allow nested parallel sections as deeply as supported
+	omp_set_max_active_levels(OPEN_MP_MAX_ACTIVE);
 
 	// Initialize FFMpeg, and register all formats and codecs
 	AV_REGISTER_ALL
@@ -877,11 +882,6 @@ std::shared_ptr<Frame> FFmpegReader::ReadStream(int64_t requested_frame) {
 	int minimum_packets = OPEN_MP_NUM_PROCESSORS;
 	int max_packets = 4096;
 
-	// Set the number of threads in OpenMP
-	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
-	// Allow nested OpenMP sections
-	omp_set_nested(true);
-
 	// Debug output
 	ZmqLogger::Instance()->AppendDebugMethod("FFmpegReader::ReadStream", "requested_frame", requested_frame, "OPEN_MP_NUM_PROCESSORS", OPEN_MP_NUM_PROCESSORS);
 
diff --git a/src/FFmpegWriter.cpp b/src/FFmpegWriter.cpp
index eff2507e..39a3768f 100644
--- a/src/FFmpegWriter.cpp
+++ b/src/FFmpegWriter.cpp
@@ -95,6 +95,12 @@ FFmpegWriter::FFmpegWriter(const std::string& path) :
 	info.has_audio = false;
 	info.has_video = false;
 
+	// Configure OpenMP parallelism
+	// Default number of threads per block
+	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
+	// Allow nested parallel sections as deeply as supported
+	omp_set_max_active_levels(OPEN_MP_MAX_ACTIVE);
+
 	// Initialize FFMpeg, and register all formats and codecs
 	AV_REGISTER_ALL
 
@@ -714,11 +720,6 @@ void FFmpegWriter::write_queued_frames() {
 	spooled_video_frames.clear();
 	spooled_audio_frames.clear();
 
-	// Set the number of threads in OpenMP
-	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
-	// Allow nested OpenMP sections
-	omp_set_nested(true);
-
 	// Create blank exception
 	bool has_error_encoding_video = false;
 
diff --git a/src/Timeline.cpp b/src/Timeline.cpp
index 124058ac..89f0992c 100644
--- a/src/Timeline.cpp
+++ b/src/Timeline.cpp
@@ -67,7 +67,13 @@ Timeline::Timeline(int width, int height, Fraction fps, int sample_rate, int cha
 	info.acodec = "openshot::timeline";
 	info.vcodec = "openshot::timeline";
 
-    // Init max image size
+	// Configure OpenMP parallelism
+	// Default number of threads per block
+	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
+	// Allow nested parallel sections as deeply as supported
+	omp_set_max_active_levels(OPEN_MP_MAX_ACTIVE);
+
+	// Init max image size
 	SetMaxSize(info.width, info.height);
 
 	// Init cache
@@ -194,6 +200,12 @@ Timeline::Timeline(std::string projectPath, bool convert_absolute_paths) :
 	info.has_video = true;
 	info.has_audio = true;
 
+	// Configure OpenMP parallelism
+	// Default number of threads per section
+	omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
+	// Allow nested parallel sections as deeply as supported
+	omp_set_max_active_levels(OPEN_MP_MAX_ACTIVE);
+
 	// Init max image size
 	SetMaxSize(info.width, info.height);
 
@@ -892,10 +904,6 @@ std::shared_ptr<Frame> Timeline::GetFrame(int64_t requested_frame)
 		#pragma omp critical (T_GetFrame)
 		nearby_clips = find_intersecting_clips(requested_frame, minimum_frames, true);
 
-		omp_set_num_threads(OPEN_MP_NUM_PROCESSORS);
-		// Allow nested OpenMP sections
-		omp_set_nested(true);
-
 		// Debug output
 		ZmqLogger::Instance()->AppendDebugMethod("Timeline::GetFrame", "requested_frame", requested_frame, "minimum_frames", minimum_frames, "OPEN_MP_NUM_PROCESSORS", OPEN_MP_NUM_PROCESSORS);