dxgi截图超时无法正常捕获屏幕

Question

使用dxgi截图的时候如果桌面不发生变化好像就不会正常捕获，用imshow展现出来的窗口会黑屏，这是我的代码，我需要如何改进

#include <dxgi1_2.h>
#include <d3d11.h>
#include <wrl/client.h>
#include <opencv2/opencv.hpp>
#include <iostream>

using Microsoft::WRL::ComPtr;

cv::Mat capture_screen_dxgi() {
    // 初始化 D3D11 设备和上下文
    ComPtr<ID3D11Device> d3dDevice;
    ComPtr<ID3D11DeviceContext> d3dContext;
    D3D11CreateDevice(nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, 0, nullptr, 0, D3D11_SDK_VERSION, &d3dDevice, nullptr, &d3dContext);

    // 获取 DXGI 设备
    ComPtr<IDXGIDevice> dxgiDevice;
    d3dDevice.As(&dxgiDevice);

    // 获取 DXGI 工厂
    ComPtr<IDXGIAdapter> dxgiAdapter;
    dxgiDevice->GetAdapter(&dxgiAdapter);
    ComPtr<IDXGIFactory2> dxgiFactory;
    dxgiAdapter->GetParent(__uuidof(IDXGIFactory2), &dxgiFactory);

    // 获取输出（即屏幕）
    ComPtr<IDXGIOutput> dxgiOutput;
    dxgiAdapter->EnumOutputs(0, &dxgiOutput);

    // 获取输出的描述
    DXGI_OUTPUT_DESC outputDesc;
    dxgiOutput->GetDesc(&outputDesc);

    // 创建输出复制（duplication）接口
    ComPtr<IDXGIOutput1> dxgiOutput1;
    dxgiOutput.As(&dxgiOutput1);
    ComPtr<IDXGIOutputDuplication> outputDuplication;
    dxgiOutput1->DuplicateOutput(d3dDevice.Get(), &outputDuplication);

    // 轮询并获取屏幕帧
    DXGI_OUTDUPL_FRAME_INFO frameInfo;
    ComPtr<IDXGIResource> desktopResource;
    HRESULT hr = outputDuplication->AcquireNextFrame(500, &frameInfo, &desktopResource);
    
    if (FAILED(hr)) {
        std::cerr << "Failed to acquire frame from output duplication!" << std::endl;
        return cv::Mat();
    }

    // 获取帧资源
    ComPtr<ID3D11Texture2D> acquiredDesktopImage;
    desktopResource.As(&acquiredDesktopImage);

    // 获取屏幕描述
    D3D11_TEXTURE2D_DESC textureDesc;
    acquiredDesktopImage->GetDesc(&textureDesc);

    // 创建 CPU 访问的纹理
    D3D11_TEXTURE2D_DESC cpuTextureDesc = textureDesc;
    cpuTextureDesc.Usage = D3D11_USAGE_STAGING;
    cpuTextureDesc.BindFlags = 0;
    cpuTextureDesc.CPUAccessFlags = D3D11_CPU_ACCESS_READ;
    cpuTextureDesc.MiscFlags = 0;

    ComPtr<ID3D11Texture2D> cpuTexture;
    d3dDevice->CreateTexture2D(&cpuTextureDesc, nullptr, &cpuTexture);

    // 将屏幕图像拷贝到 CPU 访问的纹理中
    d3dContext->CopyResource(cpuTexture.Get(), acquiredDesktopImage.Get());

    // 映射纹理以获取数据
    D3D11_MAPPED_SUBRESOURCE mappedResource;
    d3dContext->Map(cpuTexture.Get(), 0, D3D11_MAP_READ, 0, &mappedResource);

    // 创建 OpenCV Mat 对象
    cv::Mat screenshot(textureDesc.Height, textureDesc.Width, CV_8UC4, mappedResource.pData, mappedResource.RowPitch);

    // 解锁资源
    d3dContext->Unmap(cpuTexture.Get(), 0);
    outputDuplication->ReleaseFrame();

    // 转换为 BGR 格式
    cv::cvtColor(screenshot, screenshot, cv::COLOR_BGRA2BGR);

    return screenshot;
}

Answer 1

以下内容由AIGC 及 gpt.4o 科技梦想家编程波士 共同为您回答解决方案、有用望采纳☀️☀️：

你的代码看起来大体上是正确的，但黑屏问题可能与几个因素有关。首先，确保你在调用 AcquireNextFrame 时，桌面确实有变化。可以尝试在调用之前加一些延时或者确保窗口在前台。其次，确保在创建 CPU 访问的纹理时，textureDesc 的格式支持转换为 BGR。你也可以尝试将 D3D11_TEXTURE2D_DESC 中的 Format 设置为 DXGI_FORMAT_B8G8R8A8_UNORM。最后，确认 OpenCV 窗口使用的是正确的格式，可以尝试先显示原始数据，排查问题。希望这些建议能帮助你进一步深入调试！

好的，下面是改进后的代码，包含了一些调整和建议，旨在帮助解决黑屏问题：

```bash
#include <dxgi1_2.h>
#include <d3d11.h>
#include <wrl/client.h>
#include <opencv2/opencv.hpp>
#include <iostream>
#include <thread> // 用于延时

using Microsoft::WRL::ComPtr;

cv::Mat capture_screen_dxgi() {
    // 初始化 D3D11 设备和上下文
    ComPtr<ID3D11Device> d3dDevice;
    ComPtr<ID3D11DeviceContext> d3dContext;
    D3D11CreateDevice(nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, 0, nullptr, 0, D3D11_SDK_VERSION, &d3dDevice, nullptr, &d3dContext);

    // 获取 DXGI 设备
    ComPtr<IDXGIDevice> dxgiDevice;
    d3dDevice.As(&dxgiDevice);

    // 获取 DXGI 工厂
    ComPtr<IDXGIAdapter> dxgiAdapter;
    dxgiDevice->GetAdapter(&dxgiAdapter);
    ComPtr<IDXGIFactory2> dxgiFactory;
    dxgiAdapter->GetParent(__uuidof(IDXGIFactory2), &dxgiFactory);

    // 获取输出（即屏幕）
    ComPtr<IDXGIOutput> dxgiOutput;
    dxgiAdapter->EnumOutputs(0, &dxgiOutput);

    // 获取输出的描述
    DXGI_OUTPUT_DESC outputDesc;
    dxgiOutput->GetDesc(&outputDesc);

    // 创建输出复制（duplication）接口
    ComPtr<IDXGIOutput1> dxgiOutput1;
    dxgiOutput.As(&dxgiOutput1);
    ComPtr<IDXGIOutputDuplication> outputDuplication;
    dxgiOutput1->DuplicateOutput(d3dDevice.Get(), &outputDuplication);

    // 等待屏幕变化，防止黑屏
    std::this_thread::sleep_for(std::chrono::milliseconds(100));

    // 轮询并获取屏幕帧
    DXGI_OUTDUPL_FRAME_INFO frameInfo;
    ComPtr<IDXGIResource> desktopResource;
    HRESULT hr = outputDuplication->AcquireNextFrame(500, &frameInfo, &desktopResource);
    
    if (FAILED(hr)) {
        std::cerr << "Failed to acquire frame from output duplication!" << std::endl;
        return cv::Mat();
    }

    // 获取帧资源
    ComPtr<ID3D11Texture2D> acquiredDesktopImage;
    desktopResource.As(&acquiredDesktopImage);

    // 获取屏幕描述
    D3D11_TEXTURE2D_DESC textureDesc;
    acquiredDesktopImage->GetDesc(&textureDesc);

    // 创建 CPU 访问的纹理
    D3D11_TEXTURE2D_DESC cpuTextureDesc = textureDesc;
    cpuTextureDesc.Usage = D3D11_USAGE_STAGING;
    cpuTextureDesc.BindFlags = 0;
    cpuTextureDesc.CPUAccessFlags = D3D11_CPU_ACCESS_READ;
    cpuTextureDesc.MiscFlags = 0;

    ComPtr<ID3D11Texture2D> cpuTexture;
    d3dDevice->CreateTexture2D(&cpuTextureDesc, nullptr, &cpuTexture);

    // 将屏幕图像拷贝到 CPU 访问的纹理中
    d3dContext->CopyResource(cpuTexture.Get(), acquiredDesktopImage.Get());

    // 映射纹理以获取数据
    D3D11_MAPPED_SUBRESOURCE mappedResource;
    d3dContext->Map(cpuTexture.Get(), 0, D3D11_MAP_READ, 0, &mappedResource);

    // 创建 OpenCV Mat 对象
    cv::Mat screenshot(textureDesc.Height, textureDesc.Width, CV_8UC4, mappedResource.pData, mappedResource.RowPitch);

    // 解锁资源
    d3dContext->Unmap(cpuTexture.Get(), 0);
    outputDuplication->ReleaseFrame();

    // 转换为 BGR 格式
    cv::cvtColor(screenshot, screenshot, cv::COLOR_BGRA2BGR);

    return screenshot;
}

int main() {
    cv::Mat screenshot = capture_screen_dxgi();
    if (!screenshot.empty()) {
        cv::imshow("Screenshot", screenshot);
        cv::waitKey(0); // 等待按键以关闭窗口
    }
    return 0;
}

主要改动：
延时：在获取屏幕帧之前增加了短暂的延时，确保屏幕状态有变化。
错误处理：保持原有错误处理逻辑，以防获取帧失败。
主函数：加入了简单的主函数用于测试截图功能。
你可以运行这个代码并查看截图是否正常。如果仍然有问题，可以进一步检查设备的支持以及其他配置。