Warp Mesh

This example shows usage of Warp node to warp the input image frame.

Setup

Please run the install script to download all required dependencies. Please note that this script must be ran from git context, so you have to download the depthai-python repository first and then run the script

git clone https://github.com/luxonis/depthai-python.git
cd depthai-python/examples
python3 install_requirements.py

For additional information, please follow installation guide

Demo

https://user-images.githubusercontent.com/18037362/214597821-2f76239a-48fa-4146-ba47-9cad872454ea.png

Warped images

Source code

Python

C++

Also available on GitHub

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#!/usr/bin/env python3
import cv2
import depthai as dai
import numpy as np

# Create pipeline
pipeline = dai.Pipeline()

camRgb = pipeline.create(dai.node.ColorCamera)
camRgb.setPreviewSize(496, 496)
camRgb.setInterleaved(False)
maxFrameSize = camRgb.getPreviewWidth() * camRgb.getPreviewHeight() * 3

# Warp preview frame 1
warp1 = pipeline.create(dai.node.Warp)
# Create a custom warp mesh
tl = dai.Point2f(20, 20)
tr = dai.Point2f(460, 20)
ml = dai.Point2f(100, 250)
mr = dai.Point2f(400, 250)
bl = dai.Point2f(20, 460)
br = dai.Point2f(460, 460)
warp1.setWarpMesh([tl,tr,ml,mr,bl,br], 2, 3)
WARP1_OUTPUT_FRAME_SIZE = (992,500)
warp1.setOutputSize(WARP1_OUTPUT_FRAME_SIZE)
warp1.setMaxOutputFrameSize(WARP1_OUTPUT_FRAME_SIZE[0] * WARP1_OUTPUT_FRAME_SIZE[1] * 3)
warp1.setHwIds([1])
warp1.setInterpolation(dai.Interpolation.NEAREST_NEIGHBOR)

camRgb.preview.link(warp1.inputImage)
xout1 = pipeline.create(dai.node.XLinkOut)
xout1.setStreamName('out1')
warp1.out.link(xout1.input)

# Warp preview frame 2
warp2 = pipeline.create(dai.node.Warp)
# Create a custom warp mesh
mesh2 = [
    (20, 20), (250, 100), (460, 20),
    (100, 250), (250, 250), (400, 250),
    (20, 480), (250, 400), (460,480)
]
warp2.setWarpMesh(mesh2, 3, 3)
warp2.setMaxOutputFrameSize(maxFrameSize)
warp1.setHwIds([2])
warp2.setInterpolation(dai.Interpolation.BICUBIC)

camRgb.preview.link(warp2.inputImage)
xout2 = pipeline.create(dai.node.XLinkOut)
xout2.setStreamName('out2')
warp2.out.link(xout2.input)

# Connect to device and start pipeline
with dai.Device(pipeline) as device:
    # Output queue will be used to get the rgb frames from the output defined above
    q1 = device.getOutputQueue(name="out1", maxSize=8, blocking=False)
    q2 = device.getOutputQueue(name="out2", maxSize=8, blocking=False)

    while True:
        in1 = q1.get()
        if in1 is not None:
            cv2.imshow("Warped preview 1", in1.getCvFrame())
        in2 = q2.get()
        if in2 is not None:
            cv2.imshow("Warped preview 2", in2.getCvFrame())

        if cv2.waitKey(1) == ord('q'):
            break

Also available on GitHub

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#include <iostream>

// Inludes common necessary includes for development using depthai library
#include "depthai/depthai.hpp"

int main() {
    using namespace std;

    // Create pipeline
    dai::Pipeline pipeline;

    auto camRgb = pipeline.create<dai::node::ColorCamera>();
    camRgb->setPreviewSize(496, 496);
    camRgb->setInterleaved(false);
    auto maxFrameSize = camRgb->getPreviewWidth() * camRgb->getPreviewHeight() * 3;

    // Warp preview frame 1
    auto warp1 = pipeline.create<dai::node::Warp>();
    // Create a custom warp mesh
    dai::Point2f tl(20, 20);
    dai::Point2f tr(460, 20);
    dai::Point2f ml(100, 250);
    dai::Point2f mr(400, 250);
    dai::Point2f bl(20, 460);
    dai::Point2f br(460, 460);
    warp1->setWarpMesh({tl, tr, ml, mr, bl, br}, 2, 3);
    constexpr std::tuple<int, int> WARP1_OUTPUT_FRAME_SIZE = {992, 500};
    warp1->setOutputSize(WARP1_OUTPUT_FRAME_SIZE);
    warp1->setMaxOutputFrameSize(std::get<0>(WARP1_OUTPUT_FRAME_SIZE) * std::get<1>(WARP1_OUTPUT_FRAME_SIZE) * 3);
    warp1->setInterpolation(dai::Interpolation::NEAREST_NEIGHBOR);
    warp1->setHwIds({1});

    camRgb->preview.link(warp1->inputImage);
    auto xout1 = pipeline.create<dai::node::XLinkOut>();
    xout1->setStreamName("out1");
    warp1->out.link(xout1->input);

    // Warp preview frame 2
    auto warp2 = pipeline.create<dai::node::Warp>();
    // Create a custom warp mesh
    // clang-format off
    std::vector<dai::Point2f> mesh2 = {
        {20, 20}, {250, 100}, {460, 20},
        {100,250}, {250, 250}, {400, 250},
        {20, 480}, {250,400}, {460,480}
    };
    // clang-format on
    warp2->setWarpMesh(mesh2, 3, 3);
    warp2->setMaxOutputFrameSize(maxFrameSize);
    warp2->setInterpolation(dai::Interpolation::BICUBIC);
    warp2->setHwIds({2});

    camRgb->preview.link(warp2->inputImage);
    auto xout2 = pipeline.create<dai::node::XLinkOut>();
    xout2->setStreamName("out2");
    warp2->out.link(xout2->input);

    dai::Device device(pipeline);
    auto q1 = device.getOutputQueue("out1", 8, false);
    auto q2 = device.getOutputQueue("out2", 8, false);
    while(true) {
        auto in1 = q1->get<dai::ImgFrame>();
        if(in1) {
            cv::imshow("Warped preview 1", in1->getCvFrame());
        }
        auto in2 = q2->get<dai::ImgFrame>();
        if(in2) {
            cv::imshow("Warped preview 2", in2->getCvFrame());
        }
        int key = cv::waitKey(1);
        if(key == 'q' || key == 'Q') return 0;
    }
    return 0;
}

Got questions?

Head over to Discussion Forum for technical support or any other questions you might have.