Question

我正在进行桌面屏幕捕获，并希望输出为视频文件。目前我有代码从here到输出png图像。我稍微修改了代码以将输出更改为JPEG文件，然后使用openCV 3.0.0将其转换为avi视频输出。原因我需要JPEG文件作为输出是因为我在Windows 8.1和OpenCV VideoWriter :: fourcc上运行（＆＃39; M＆＃39;，＆＃39; J＆＃39;，＆＃39; P＆＃39;，＆＃39; G＆＃39;）是唯一适用于我的选项。

PNG图像的输出完美但不是JPEG。图像上有垂直线，生成JPEG输出的时间比PNG长得多。

我有2个选项：

改善JPEG文件的输出，使其工作更快，图像清晰。
摆脱OpenCV 3.0.0问题以接受PNG文件输入并能够输出视频文件。（最好是AVI / MP4文件格式）

任何一种解决方案都能为我做到。请帮忙。谢谢。

我的代码：

#include "stdafx.h"
#include <Wincodec.h>             // we use WIC for saving images
#include <d3d9.h>                 // DirectX 9 header
#include <opencv\cv.h>
#include <opencv\cxcore.hpp>
#include <opencv2\highgui\highgui.hpp>
#pragma comment(lib, "d3d9.lib")  // link to DirectX 9 library

using namespace cv;

#define WIDEN2(x) L ## x
#define WIDEN(x) WIDEN2(x)
#define __WFILE__ WIDEN(__FILE__)
#define HRCHECK(__expr) {hr=(__expr);if(FAILED(hr)){wprintf(L"FAILURE 0x%08X (%i)\n\tline: %u file: '%s'\n\texpr: '" WIDEN(#__expr) L"'\n",hr, hr, __LINE__,__WFILE__);goto cleanup;}}
#define RELEASE(__p) {if(__p!=nullptr){__p->Release();__p=nullptr;}}

HRESULT Direct3D9TakeScreenshots(UINT adapter, UINT count);
HRESULT SavePixelsToFile32bppPBGRA(UINT width, UINT height, UINT stride, LPBYTE pixels, LPWSTR filePath, const GUID &format);


int _tmain(int argc, _TCHAR* argv[])
{
    HRESULT hr = Direct3D9TakeScreenshots(D3DADAPTER_DEFAULT, 10);
    return 0;
}


HRESULT Direct3D9TakeScreenshots(UINT adapter, UINT count)
{
    HRESULT hr = S_OK;
    IDirect3D9 *d3d = nullptr;
    IDirect3DDevice9 *device = nullptr;
    IDirect3DSurface9 *surface = nullptr;
    D3DPRESENT_PARAMETERS parameters = { 0 };
    D3DDISPLAYMODE mode;
    D3DLOCKED_RECT rc;
    UINT pitch;
    SYSTEMTIME st;
    LPBYTE *shots = nullptr;

    // init D3D and get screen size
    d3d = Direct3DCreate9(D3D_SDK_VERSION);
    HRCHECK(d3d->GetAdapterDisplayMode(adapter, &mode));

    parameters.Windowed = TRUE;
    parameters.BackBufferCount = 1;
    parameters.BackBufferHeight = mode.Height;
    parameters.BackBufferWidth = mode.Width;
    parameters.SwapEffect = D3DSWAPEFFECT_DISCARD;
    parameters.hDeviceWindow = NULL;

    // create device & capture surface
    HRCHECK(d3d->CreateDevice(adapter, D3DDEVTYPE_HAL, NULL, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &parameters, &device));
    HRCHECK(device->CreateOffscreenPlainSurface(mode.Width, mode.Height, D3DFMT_A8R8G8B8, D3DPOOL_SYSTEMMEM, &surface, nullptr));

    // compute the required buffer size
    HRCHECK(surface->LockRect(&rc, NULL, 0));
    pitch = rc.Pitch;
    HRCHECK(surface->UnlockRect());

    // allocate screenshots buffers
    shots = new LPBYTE[count];
    for (UINT i = 0; i < count; i++)
    {
        shots[i] = new BYTE[pitch * mode.Height];
    }

    GetSystemTime(&st); // measure the time we spend doing <count> captures
    wprintf(L"START Capture--> %i:%i:%i.%i\n", st.wHour, st.wMinute, st.wSecond, st.wMilliseconds);
    for (UINT i = 0; i < count; i++)
    {
        // get the data
        HRCHECK(device->GetFrontBufferData(0, surface));

        // copy it into our buffers
        HRCHECK(surface->LockRect(&rc, NULL, 0));
        CopyMemory(shots[i], rc.pBits, rc.Pitch * mode.Height);
        HRCHECK(surface->UnlockRect());
    }
    GetSystemTime(&st);
    wprintf(L"END Capture--> %i:%i:%i.%i\n", st.wHour, st.wMinute, st.wSecond, st.wMilliseconds);

    // save all screenshots
    for (UINT i = 0; i < count; i++)
    {
        WCHAR file[100];
        wsprintf(file, L"cap%i.jpg", i);
        HRCHECK(SavePixelsToFile32bppPBGRA(mode.Width, mode.Height, pitch, shots[i], file, GUID_ContainerFormatJpeg));
    }

    cleanup:
    if (shots != nullptr)
    {
        for (UINT i = 0; i < count; i++)
        {
        delete shots[i];
        }
        delete[] shots;
    }

    RELEASE(surface);
    RELEASE(device);
    RELEASE(d3d);
    return hr;
}

HRESULT SavePixelsToFile32bppPBGRA(UINT width, UINT height, UINT stride, LPBYTE pixels, LPWSTR filePath, const GUID &format)
{
    if (!filePath || !pixels)
        return E_INVALIDARG;

    HRESULT hr = S_OK;
    IWICImagingFactory *factory = nullptr;
    IWICBitmapEncoder *encoder = nullptr;
    IWICBitmapFrameEncode *frame = nullptr;
    IWICStream *stream = nullptr;
    GUID pf = GUID_WICPixelFormat32bppPBGRA;
    BOOL coInit = CoInitialize(nullptr);

    HRCHECK(CoCreateInstance(CLSID_WICImagingFactory, nullptr, CLSCTX_INPROC_SERVER, IID_PPV_ARGS(&factory)));
    HRCHECK(factory->CreateStream(&stream));
    HRCHECK(stream->InitializeFromFilename(filePath, GENERIC_WRITE));
    HRCHECK(factory->CreateEncoder(format, nullptr, &encoder));
    HRCHECK(encoder->Initialize(stream, WICBitmapEncoderNoCache));
    HRCHECK(encoder->CreateNewFrame(&frame, nullptr)); // we don't use options here
    HRCHECK(frame->Initialize(nullptr)); // we dont' use any options here
    HRCHECK(frame->SetSize(width, height));
    HRCHECK(frame->SetPixelFormat(&pf));
    HRCHECK(frame->WritePixels(height, stride, stride * height, pixels));
    HRCHECK(frame->Commit());
    HRCHECK(encoder->Commit());

    cleanup:
    RELEASE(stream);
    RELEASE(frame);
    RELEASE(encoder);
    RELEASE(factory);
    if (coInit) CoUninitialize();

    //This part do encode JPEG file to video file 
    VideoCapture in_capture("cap%d.jpg");

    Mat img;

    VideoWriter out_capture("video.avi", CV_FOURCC('M','J','P','G'), 1, Size(1920,1080));

    while (true)
    {
        in_capture >> img;
        if(img.empty())
            break;

        out_capture.write(img);
    }

    return hr;
}

Answer 1

您的图片不正确，因为JPEG编码器会编码3种格式JPEG Native Codec：

GUID_WICPixelFormat8bppGray
GUID_WICPixelFormat24bppBGR
GUID_WICPixelFormat32bppCMYK

你试过D3DXSaveSurfaceToFile，是不是太慢了？

修改

对于你的第二个选择，我已经制作了一个程序，用Media Foundation将屏幕截图编码为h264：

这项工作在Windows 7上，分辨率为1280 * 1024，性能合理，但我不知道它是否满足您的需求。

此程序不是实时捕获，也许您必须更正传递给接收器编写器的时间戳。考虑使用Media Foundation时钟。

您可以尝试更改编码格式：MF_TRANSCODE_CONTAINERTYPE

请注意编码器的分辨率有限。

更改MF_MT_AVG_BITRATE可以提高质量而不是性能。根据您的要求设置值。

在我的系统上，捕获图像是反向的，所以我需要以严格的方式复制图像（请参阅#define REVERSE_IMAGE）。也许它比MFCopyImage慢，但在测试两种实现后我都不确定。

我们不需要WIC，因为Media Foundation编码器处理d3d9捕获的格式。

在Windows 7上，请考虑使用IDirect3DDevice9Ex而不是idirect3ddevice9。

我已将您的d3d9捕获代码与本教程混合：Using the Sink Writer to Encode Video。该计划的设计也可以改进。

以下是代码：

#include <Windows.h> #include <mfapi.h> #include <mfidl.h> #include <Mfreadwrite.h> #include <mferror.h> #include <d3d9.h> #pragma comment(lib, "mfreadwrite") #pragma comment(lib, "mfplat") #pragma comment(lib, "mfuuid") #pragma comment(lib, "d3d9.lib") template <class T> void SafeRelease(T **ppT){ if(*ppT){ (*ppT)->Release(); *ppT = NULL; } } #define REVERSE_IMAGE // Format constants const UINT32 VIDEO_FPS = 30; const UINT64 VIDEO_FRAME_DURATION = 10 * 1000 * 1000 / VIDEO_FPS; const UINT32 VIDEO_BIT_RATE = 2000000; const GUID VIDEO_ENCODING_FORMAT = MFVideoFormat_H264; const GUID VIDEO_INPUT_FORMAT = MFVideoFormat_RGB32; const UINT32 VIDEO_FRAME_COUNT = 5 * VIDEO_FPS; HRESULT InitializeDirect3D9(IDirect3DDevice9** ppDevice, IDirect3DSurface9** ppSurface, UINT32& uiWidth, UINT32& uiHeight){ IDirect3D9* d3d = NULL; d3d = Direct3DCreate9(D3D_SDK_VERSION); if(d3d == NULL) return E_POINTER; D3DDISPLAYMODE mode; HRESULT hr = d3d->GetAdapterDisplayMode(D3DADAPTER_DEFAULT, &mode); if(FAILED(hr)){ SafeRelease(&d3d); return hr; } D3DPRESENT_PARAMETERS parameters = {0}; parameters.Windowed = TRUE; parameters.BackBufferCount = 1; uiHeight = parameters.BackBufferHeight = mode.Height; uiWidth = parameters.BackBufferWidth = mode.Width; parameters.SwapEffect = D3DSWAPEFFECT_DISCARD; parameters.hDeviceWindow = NULL; hr = d3d->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, NULL, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &parameters, ppDevice); if(FAILED(hr)){ SafeRelease(&d3d); return hr; } hr = (*ppDevice)->CreateOffscreenPlainSurface(mode.Width, mode.Height, D3DFMT_A8R8G8B8, D3DPOOL_SYSTEMMEM, ppSurface, nullptr); SafeRelease(&d3d); return hr; } HRESULT InitializeSinkWriter(IMFSinkWriter **ppWriter, DWORD *pStreamIndex, const UINT32 uiWidth, const UINT32 uiHeight){ *ppWriter = NULL; *pStreamIndex = NULL; IMFSinkWriter *pSinkWriter = NULL; IMFMediaType *pMediaTypeOut = NULL; IMFMediaType *pMediaTypeIn = NULL; DWORD streamIndex; HRESULT hr = MFCreateSinkWriterFromURL(L"output.mp4", NULL, NULL, &pSinkWriter); // Set the output media type. if(SUCCEEDED(hr)){ hr = MFCreateMediaType(&pMediaTypeOut); } if(SUCCEEDED(hr)){ hr = pMediaTypeOut->SetGUID(MF_MT_MAJOR_TYPE, MFMediaType_Video); } if(SUCCEEDED(hr)){ hr = pMediaTypeOut->SetGUID(MF_MT_SUBTYPE, VIDEO_ENCODING_FORMAT); } if(SUCCEEDED(hr)){ hr = pMediaTypeOut->SetUINT32(MF_MT_AVG_BITRATE, VIDEO_BIT_RATE); } if(SUCCEEDED(hr)){ hr = pMediaTypeOut->SetUINT32(MF_MT_INTERLACE_MODE, MFVideoInterlace_Progressive); } if(SUCCEEDED(hr)){ hr = MFSetAttributeSize(pMediaTypeOut, MF_MT_FRAME_SIZE, uiWidth, uiHeight); } if(SUCCEEDED(hr)){ hr = MFSetAttributeRatio(pMediaTypeOut, MF_MT_FRAME_RATE, VIDEO_FPS, 1); } if(SUCCEEDED(hr)){ hr = MFSetAttributeRatio(pMediaTypeOut, MF_MT_PIXEL_ASPECT_RATIO, 1, 1); } if(SUCCEEDED(hr)){ hr = pSinkWriter->AddStream(pMediaTypeOut, &streamIndex); } // Set the input media type. if(SUCCEEDED(hr)){ hr = MFCreateMediaType(&pMediaTypeIn); } if(SUCCEEDED(hr)){ hr = pMediaTypeIn->SetGUID(MF_MT_MAJOR_TYPE, MFMediaType_Video); } if(SUCCEEDED(hr)){ hr = pMediaTypeIn->SetGUID(MF_MT_SUBTYPE, VIDEO_INPUT_FORMAT); } if(SUCCEEDED(hr)){ hr = pMediaTypeIn->SetUINT32(MF_MT_INTERLACE_MODE, MFVideoInterlace_Progressive); } if(SUCCEEDED(hr)){ hr = MFSetAttributeSize(pMediaTypeIn, MF_MT_FRAME_SIZE, uiWidth, uiHeight); } if(SUCCEEDED(hr)){ hr = MFSetAttributeRatio(pMediaTypeIn, MF_MT_FRAME_RATE, VIDEO_FPS, 1); } if(SUCCEEDED(hr)){ hr = MFSetAttributeRatio(pMediaTypeIn, MF_MT_PIXEL_ASPECT_RATIO, 1, 1); } if(SUCCEEDED(hr)){ hr = pSinkWriter->SetInputMediaType(streamIndex, pMediaTypeIn, NULL); } // Tell the sink writer to start accepting data. if(SUCCEEDED(hr)){ hr = pSinkWriter->BeginWriting(); } // Return the pointer to the caller. if(SUCCEEDED(hr)){ *ppWriter = pSinkWriter; (*ppWriter)->AddRef(); *pStreamIndex = streamIndex; } SafeRelease(&pSinkWriter); SafeRelease(&pMediaTypeOut); SafeRelease(&pMediaTypeIn); return hr; } HRESULT WriteFrame(IDirect3DDevice9* pDevice, IDirect3DSurface9* pSurface, IMFSinkWriter* pWriter, DWORD streamIndex, const LONGLONG& rtStart, const UINT32 uiWidth, const UINT32 uiHeight){ HRESULT hr = pDevice->GetFrontBufferData(0, pSurface); if(FAILED(hr)){ return hr; } D3DLOCKED_RECT rc; hr = pSurface->LockRect(&rc, NULL, 0); if(FAILED(hr)){ return hr; } IMFSample *pSample = NULL; IMFMediaBuffer *pBuffer = NULL; const LONG cbWidth = 4 * uiWidth; const DWORD cbBuffer = cbWidth * uiHeight; BYTE *pData = NULL; // Create a new memory buffer. hr = MFCreateMemoryBuffer(cbBuffer, &pBuffer); // Lock the buffer and copy the video frame to the buffer. if(SUCCEEDED(hr)){ hr = pBuffer->Lock(&pData, NULL, NULL); } if(SUCCEEDED(hr)){ #ifdef REVERSE_IMAGE for(int i = 0, j = uiHeight - 1; i < uiHeight; i++, j--) for(int k = 0; k < cbWidth; k++) pData[(i * cbWidth) + k] = ((BYTE*)rc.pBits)[(j * cbWidth) + k]; #else hr = MFCopyImage(pData, cbWidth, (BYTE*)rc.pBits, rc.Pitch, cbWidth, uiHeight); #endif } if(pBuffer){ pBuffer->Unlock(); } // Set the data length of the buffer. if(SUCCEEDED(hr)){ hr = pBuffer->SetCurrentLength(cbBuffer); } // Create a media sample and add the buffer to the sample. if(SUCCEEDED(hr)){ hr = MFCreateSample(&pSample); } if(SUCCEEDED(hr)){ hr = pSample->AddBuffer(pBuffer); } // Set the time stamp and the duration. if(SUCCEEDED(hr)){ hr = pSample->SetSampleTime(rtStart); } if(SUCCEEDED(hr)){ hr = pSample->SetSampleDuration(VIDEO_FRAME_DURATION); } // Send the sample to the Sink Writer. if(SUCCEEDED(hr)){ hr = pWriter->WriteSample(streamIndex, pSample); } hr = pSurface->UnlockRect(); SafeRelease(&pSample); SafeRelease(&pBuffer); return hr; } void main(){ HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED); if(SUCCEEDED(hr)){ hr = MFStartup(MF_VERSION); if(SUCCEEDED(hr)){ UINT32 uiWidth = 0; UINT32 uiHeight = 0; IDirect3DDevice9* pDevice = NULL; IDirect3DSurface9* pSurface = NULL; hr = InitializeDirect3D9(&pDevice, &pSurface, uiWidth, uiHeight); if(SUCCEEDED(hr)){ IMFSinkWriter *pSinkWriter = NULL; DWORD stream; hr = InitializeSinkWriter(&pSinkWriter, &stream, uiWidth, uiHeight); if(SUCCEEDED(hr)){ LONGLONG rtStart = 0; for(DWORD i = 0; i < VIDEO_FRAME_COUNT; ++i){ hr = WriteFrame(pDevice, pSurface, pSinkWriter, stream, rtStart, uiWidth, uiHeight); if(FAILED(hr)){ break; } rtStart += VIDEO_FRAME_DURATION; } } if(SUCCEEDED(hr)){ hr = pSinkWriter->Finalize(); } SafeRelease(&pSinkWriter); } SafeRelease(&pDevice); SafeRelease(&pSurface); MFShutdown(); } CoUninitialize(); } }

DirectX屏幕捕获和输出视频

1 个答案: