Directshow获取颜色空间分辨率

void GetColorSpaceResolution()
{
    HRESULT hr;
    AM_MEDIA_TYPE *pmt = NULL;
    VIDEOINFOHEADER *pvi = NULL;
    VIDEO_STREAM_CONFIG_CAPS scc;
    IAMStreamConfig* pConfig = 0;

    hr = pBuild->FindInterface(&PIN_CATEGORY_CAPTURE, &MEDIATYPE_Video, pCap,
        IID_IAMStreamConfig, (void**)&pConfig);
    if (FAILED(hr)) {
        qWarning() << "failed to get config on capture device";
        return;
    }


    int iCount;
    int iSize;
    hr = pConfig->GetNumberOfCapabilities(&iCount, &iSize);
    if (FAILED(hr)) {
        qWarning() << "failed to get capabilities";
        return;
    }

QList<QSize> sizes;
    QVideoFrame::PixelFormat f = QVideoFrame::Format_Invalid;

    types.clear();
    resolutions.clear();

        for (int iIndex = 0; iIndex < iCount; iIndex++) {
        hr = pConfig->GetStreamCaps(iIndex, &pmt, reinterpret_cast<BYTE*>(&scc));
        if (hr == S_OK) {
            pvi = (VIDEOINFOHEADER*)pmt->pbFormat;
            if ((pmt->majortype == MEDIATYPE_Video) &&
                (pmt->formattype == FORMAT_VideoInfo)) {
                // Add types
                if (pmt->subtype == MEDIASUBTYPE_RGB24) {
                    if (!types.contains(QVideoFrame::Format_RGB24)) {
                        types.append(QVideoFrame::Format_RGB24);
                        f = QVideoFrame::Format_RGB24;
                    }
                }
                else if (pmt->subtype == MEDIASUBTYPE_RGB32) {
                    if (!types.contains(QVideoFrame::Format_RGB32)) {
                        types.append(QVideoFrame::Format_RGB32);
                        f = QVideoFrame::Format_RGB32;
                    }
                }
                else if (pmt->subtype == MEDIASUBTYPE_YUY2) {
                    if (!types.contains(QVideoFrame::Format_YUYV)) {
                        types.append(QVideoFrame::Format_YUYV);
                        f = QVideoFrame::Format_YUYV;
                    }
                }
                else if (pmt->subtype == MEDIASUBTYPE_MJPG) {
                }
                else if (pmt->subtype == MEDIASUBTYPE_I420) {
                    if (!types.contains(QVideoFrame::Format_YUV420P)) {
                        types.append(QVideoFrame::Format_YUV420P);
                        f = QVideoFrame::Format_YUV420P;
                    }
                }
                else if (pmt->subtype == MEDIASUBTYPE_RGB555) {
                    if (!types.contains(QVideoFrame::Format_RGB555)) {
                        types.append(QVideoFrame::Format_RGB555);
                        f = QVideoFrame::Format_RGB555;
                    }
                }
                else if (pmt->subtype == MEDIASUBTYPE_YVU9) {
                }
                else if (pmt->subtype == MEDIASUBTYPE_UYVY) {
                    if (!types.contains(QVideoFrame::Format_UYVY)) {
                        types.append(QVideoFrame::Format_UYVY);
                        f = QVideoFrame::Format_UYVY;
                    }
                }
                else {
                    qWarning() << "UNKNOWN FORMAT: " << pmt->subtype.Data1;
                }
                // Add resolutions
                QSize res(pvi->bmiHeader.biWidth, pvi->bmiHeader.biHeight);
                if (!resolutions.contains(f)) {
                    sizes.clear();
                    resolutions.insert(f, sizes);
                }
                resolutions[f].append(res);
            }
        }
    }
    pConfig->Release();

    if (!types.isEmpty()) {
        // Add RGB formats and let directshow do color space conversion if required.
        if (!types.contains(QVideoFrame::Format_RGB24)) {
            types.append(QVideoFrame::Format_RGB24);
            resolutions.insert(QVideoFrame::Format_RGB24, resolutions[types.first()]);
        }
        if (!types.contains(QVideoFrame::Format_RGB32)) {
            types.append(QVideoFrame::Format_RGB32);
            resolutions.insert(QVideoFrame::Format_RGB32, resolutions[types.first()]);
        }
    }
}