Video Encode

1import depthai as dai
2
3# Capture Ctrl+C and set a flag to stop the loop
4import time
5import cv2
6import threading
7import signal
8
9PROFILE = dai.VideoEncoderProperties.Profile.MJPEG # or H265_MAIN, H264_MAIN
10
11quitEvent = threading.Event()
12signal.signal(signal.SIGTERM, lambda *_args: quitEvent.set())
13signal.signal(signal.SIGINT, lambda *_args: quitEvent.set())
14
15class VideoSaver(dai.node.HostNode):
16    def __init__(self, *args, **kwargs):
17        dai.node.HostNode.__init__(self, *args, **kwargs)
18        self.file_handle = open('video.encoded', 'wb')
19
20    def build(self, *args):
21        self.link_args(*args)
22        return self
23
24    def process(self, frame):
25        frame.getData().tofile(self.file_handle)
26
27with dai.Pipeline() as pipeline:
28    camRgb = pipeline.create(dai.node.Camera).build(dai.CameraBoardSocket.CAM_A)
29    output = camRgb.requestOutput((1920, 1440), type=dai.ImgFrame.Type.NV12)
30    outputQueue = output.createOutputQueue()
31    encoded = pipeline.create(dai.node.VideoEncoder).build(output,
32            frameRate = 30,
33            profile = PROFILE)
34    saver = pipeline.create(VideoSaver).build(encoded.out)
35
36    pipeline.start()
37    print("Started to save video to video.encoded")
38    print("Press Ctrl+C to stop")
39    timeStart = time.monotonic()
40    while pipeline.isRunning() and not quitEvent.is_set():
41        frame = outputQueue.get()
42        assert isinstance(frame, dai.ImgFrame)
43        cv2.imshow("video", frame.getCvFrame())
44        key = cv2.waitKey(1)
45        if key == ord('q'):
46            break
47    pipeline.stop()
48    pipeline.wait()
49    saver.file_handle.close()
50
51print("To view the encoded data, convert the stream file (.encoded) into a video file (.mp4) using a command below:")
52print("ffmpeg -framerate 30 -i video.encoded -c copy video.mp4")

1#include <atomic>
2#include <csignal>
3#include <fstream>
4#include <iostream>
5#include <memory>
6#include <opencv2/opencv.hpp>
7#include <thread>
8
9#include "depthai/depthai.hpp"
10#include "depthai/pipeline/datatype/MessageGroup.hpp"
11
12// Global flag for graceful shutdown
13std::atomic<bool> quitEvent(false);
14
15// Signal handler
16void signalHandler(int signum) {
17    quitEvent = true;
18}
19
20// Custom host node for saving video data
21class VideoSaver : public dai::node::CustomNode<VideoSaver> {
22   public:
23    VideoSaver() : fileHandle("video.encoded", std::ios::binary) {
24        if(!fileHandle.is_open()) {
25            throw std::runtime_error("Could not open video.encoded for writing");
26        }
27    }
28
29    ~VideoSaver() {
30        if(fileHandle.is_open()) {
31            fileHandle.close();
32        }
33    }
34
35    std::shared_ptr<dai::Buffer> processGroup(std::shared_ptr<dai::MessageGroup> message) override {
36        if(!fileHandle.is_open()) return nullptr;
37
38        // Get raw data and write to file
39        auto frame = message->get<dai::EncodedFrame>("data");
40        unsigned char* frameData = frame->getData().data();
41        size_t frameSize = frame->getData().size();
42        std::cout << "Storing frame of size: " << frameSize << std::endl;
43        fileHandle.write(reinterpret_cast<const char*>(frameData), frameSize);
44
45        // Don't send anything back
46        return nullptr;
47    }
48
49   private:
50    std::ofstream fileHandle;
51};
52
53int main() {
54    // Set up signal handlers
55    signal(SIGTERM, signalHandler);
56    signal(SIGINT, signalHandler);
57
58    // Create device
59    std::shared_ptr<dai::Device> device = std::make_shared<dai::Device>();
60
61    // Create pipeline
62    dai::Pipeline pipeline(device);
63
64    // Create nodes
65    auto camRgb = pipeline.create<dai::node::Camera>()->build(dai::CameraBoardSocket::CAM_A);
66    auto output = camRgb->requestOutput(std::make_pair(1920, 1440), dai::ImgFrame::Type::NV12);
67    auto outputQueue = output->createOutputQueue();
68
69    // Create video encoder node
70    auto encoded = pipeline.create<dai::node::VideoEncoder>();
71    encoded->setDefaultProfilePreset(30, dai::VideoEncoderProperties::Profile::MJPEG);
72    output->link(encoded->input);
73
74    // Create video saver node
75    auto saver = pipeline.create<VideoSaver>();
76    encoded->out.link(saver->inputs["data"]);
77
78    // Start pipeline
79    pipeline.start();
80    std::cout << "Started to save video to video.encoded" << std::endl;
81    std::cout << "Press Ctrl+C to stop" << std::endl;
82
83    auto timeStart = std::chrono::steady_clock::now();
84
85    while(pipeline.isRunning() && !quitEvent) {
86        auto frame = outputQueue->get<dai::ImgFrame>();
87        if(frame == nullptr) continue;
88
89        cv::imshow("video", frame->getCvFrame());
90
91        int key = cv::waitKey(1);
92        if(key == 'q') {
93            break;
94        }
95    }
96
97    // Cleanup
98    pipeline.stop();
99    pipeline.wait();
100
101    std::cout << "To view the encoded data, convert the stream file (.encoded) into a video file (.mp4) using a command below:" << std::endl;
102    std::cout << "ffmpeg -framerate 30 -i video.encoded -c copy video.mp4" << std::endl;
103
104    return 0;
105}