RidgeRun OpenCV Fork: Difference between revisions

Revision as of 15:36, 18 September 2020

Introduction

The RidgeRun OpenCV fork is a modified version of the project with various improvements around speed and efficiency. While some changes are general (i.e.: any platform will benefit from them), others are specific to the NVIDIA Jetson family.

The fork is hosted at:

https://github.com/RidgeRun/opencv

Building the Project

Follow the instructions in our Compiling OpenCV from Source page. Make sure you select:

RidgeRun fork
GStreamer support
CUDA support (if applicable)

Enhancements

GStreamer Video Capture

Effectively removes the memory copy when transferring data from the GstBuffer to the cv::Mat. Now the GstBuffer and its associated memory will remain alive throughout the lifespan of the matrix.

Tested under the following conditions

OpenCV Version: 4.4.0
FPS and CPU usage taken with the GstPerf element.
The following source:

#include <opencv2/opencv.hpp>

int main() {
  cv::VideoCapture cap(
     "videotestsrc pattern=black ! video/x-raw,format=BGR,width=3840,height=2160 ! "
     "perf print-arm-load=true ! appsink drop=false sync=false max-buffers=3", 
     cv::CAP_GSTREAMER);
  
  while(1){
    cv::Mat frame;
    cap >> frame;	
  }

  cap.release();
  return 0;
}

Build with

g++ -o benchmark benchmark.cc `pkg-config --cflags --libs opencv4` -std=c++11

Run with

GST_DEBUG=perf:4 ./benchmark

@@ Line 18: / Line 18: @@
 === GStreamer Video Capture ===
+Effectively removes the memory copy when transferring data from the GstBuffer to the cv::Mat. Now the GstBuffer and its associated memory will remain alive throughout the lifespan of the matrix.
 Tested under the following conditions
 * OpenCV Version: 4.4.0
 * FPS and CPU usage taken with the [https://github.com/ridgerun/gst-perf GstPerf] element.
-* The following script:
+* The following source:
-<source lang=python>
+<source lang=c++>
-import cv2 as cv
+#include <opencv2/opencv.hpp>
-PIPE = "videotestsrc pattern=black !  \
+int main() {
-        video/x-raw,format=BGR,width=1920,height=1080 ! \
+  cv::VideoCapture cap(
-        perf print-arm-load=true ! \
+     "videotestsrc pattern=black ! video/x-raw,format=BGR,width=3840,height=2160 ! "
-        appsink sync=false drop=false max-buffers=3"
+     "perf print-arm-load=true ! appsink drop=false sync=false max-buffers=3",
+     cv::CAP_GSTREAMER);
+  while(1){
+    cv::Mat frame;
+    cap >> frame;
+  }
-cap = cv.VideoCapture(PIPE, cv.CAP_GSTREAMER)
+  cap.release();
+  return 0;
-while True:
+}
-    ret, frame = cap.read()
+</source>
+* Build with
-cap.release()
+<source lang=bash>
-cv.destroyAllWindows()
+g++ -o benchmark benchmark.cc `pkg-config --cflags --libs opencv4` -std=c++11
 </source>
-* Execution:
+* Run with
 <source lang=bash>
-GST_DEBUG=perf:4 python3 ./benchmark.py
+GST_DEBUG=perf:4 ./benchmark
 </source>