Superb

void CMainFrame::SaveThumbnails(LPCTSTR fn)
{
    if (!pMC || !pMS || GetPlaybackMode() != PM_FILE /*&& GetPlaybackMode() != PM_DVD*/) {
        return;
    }

    REFERENCE_TIME rtPos = GetPos();
    REFERENCE_TIME rtDur = GetDur();

    if (rtDur <= 0) {
        AfxMessageBox(IDS_MAINFRM_54, MB_ICONWARNING | MB_OK, 0);
        return;
    }

    pMC->Pause();
    GetMediaState(); // wait for completion of the pause command

    CSize video, wh(0, 0), arxy(0, 0);

    if (m_pMFVDC) {
        m_pMFVDC->GetNativeVideoSize(&wh, &arxy);
    } else if (m_pCAP) {
        wh = m_pCAP->GetVideoSize(false);
        arxy = m_pCAP->GetVideoSize(true);
    } else {
        pBV->GetVideoSize(&wh.cx, &wh.cy);

        long arx = 0, ary = 0;
        CComQIPtr<IBasicVideo2> pBV2 = pBV;
        if (pBV2 && SUCCEEDED(pBV2->GetPreferredAspectRatio(&arx, &ary)) && arx > 0 && ary > 0) {
            arxy.SetSize(arx, ary);
        }
    }

    if (wh.cx <= 0 || wh.cy <= 0) {
        AfxMessageBox(IDS_MAINFRM_55, MB_ICONWARNING | MB_OK, 0);
        return;
    }

    // with the overlay mixer IBasicVideo2 won't tell the new AR when changed dynamically
    DVD_VideoAttributes VATR;
    if (GetPlaybackMode() == PM_DVD && SUCCEEDED(pDVDI->GetCurrentVideoAttributes(&VATR))) {
        arxy.SetSize(VATR.ulAspectX, VATR.ulAspectY);
    }

    video = (arxy.cx <= 0 || arxy.cy <= 0) ? wh : CSize(MulDiv(wh.cy, arxy.cx, arxy.cy), wh.cy);

    //

    const CAppSettings& s = AfxGetAppSettings();

    int cols = max(1, min(10, s.iThumbCols)), rows = max(1, min(20, s.iThumbRows));

    int margin = 5;
    int infoheight = 70;
    int width = max(256, min(2560, s.iThumbWidth));
    int height = width * video.cy / video.cx * rows / cols + infoheight;

    int dibsize = sizeof(BITMAPINFOHEADER) + width * height * 4;

    CAutoVectorPtr<BYTE> dib;
    if (!dib.Allocate(dibsize)) {
        AfxMessageBox(IDS_MAINFRM_56, MB_ICONWARNING | MB_OK, 0);
        return;
    }

    BITMAPINFOHEADER* bih = (BITMAPINFOHEADER*)(BYTE*)dib;
    memset(bih, 0, sizeof(BITMAPINFOHEADER));
    bih->biSize = sizeof(BITMAPINFOHEADER);
    bih->biWidth = width;
    bih->biHeight = height;
    bih->biPlanes = 1;
    bih->biBitCount = 32;
    bih->biCompression = BI_RGB;
    bih->biSizeImage = width * height * 4;
    memsetd(bih + 1, 0xffffff, bih->biSizeImage);

    SubPicDesc spd;
    spd.w = width;
    spd.h = height;
    spd.bpp = 32;
    spd.pitch = -width * 4;
    spd.vidrect = CRect(0, 0, width, height);
    spd.bits = (BYTE*)(bih + 1) + (width * 4) * (height - 1);

    {
        BYTE* p = (BYTE*)spd.bits;
        for (int y = 0; y < spd.h; y++, p += spd.pitch)
            for (int x = 0; x < spd.w; x++) {
                ((DWORD*)p)[x] = 0x010101 * (0xe0 + 0x08 * y / spd.h + 0x18 * (spd.w - x) / spd.w);
            }
    }

    CCritSec csSubLock;
    RECT bbox;

    for (int i = 1, pics = cols * rows; i <= pics; i++) {
        REFERENCE_TIME rt = rtDur * i / (pics + 1);
        DVD_HMSF_TIMECODE hmsf = RT2HMS_r(rt);

        SeekTo(rt);

        m_VolumeBeforeFrameStepping = m_wndToolBar.Volume;
        pBA->put_Volume(-10000);

        HRESULT hr = pFS ? pFS->Step(1, NULL) : E_FAIL;

        if (FAILED(hr)) {
            pBA->put_Volume(m_VolumeBeforeFrameStepping);
            AfxMessageBox(IDS_FRAME_STEP_ERROR_RENDERER, MB_ICONEXCLAMATION | MB_OK, 0);
            return;
        }

        HANDLE hGraphEvent = NULL;
        pME->GetEventHandle((OAEVENT*)&hGraphEvent);

        while (hGraphEvent && WaitForSingleObject(hGraphEvent, INFINITE) == WAIT_OBJECT_0) {
            LONG evCode = 0;
            LONG_PTR evParam1, evParam2;
            while (pME && SUCCEEDED(pME->GetEvent(&evCode, &evParam1, &evParam2, 0))) {
                pME->FreeEventParams(evCode, evParam1, evParam2);
                if (EC_STEP_COMPLETE == evCode) {
                    hGraphEvent = NULL;
                }
            }
        }

        pBA->put_Volume(m_VolumeBeforeFrameStepping);

        int col = (i - 1) % cols;
        int row = (i - 1) / cols;

        CSize siz((width - margin * 2) / cols, (height - margin * 2 - infoheight) / rows);
        CPoint p(margin + col * siz.cx, margin + row * siz.cy + infoheight);
        CRect r(p, siz);
        r.DeflateRect(margin, margin);

        CRenderedTextSubtitle rts(&csSubLock);
        rts.CreateDefaultStyle(0);
        rts.m_dstScreenSize.SetSize(width, height);
        STSStyle* style = DNew STSStyle();
        style->marginRect.SetRectEmpty();
        rts.AddStyle(_T("thumbs"), style);

        CStringW str;
        str.Format(L"{\\an7\\1c&Hffffff&\\4a&Hb0&\\bord1\\shad4\\be1}{\\p1}m %d %d l %d %d %d %d %d %d{\\p}",
                   r.left, r.top, r.right, r.top, r.right, r.bottom, r.left, r.bottom);
        rts.Add(str, true, 0, 1, _T("thumbs"));
        str.Format(L"{\\an3\\1c&Hffffff&\\3c&H000000&\\alpha&H80&\\fs16\\b1\\bord2\\shad0\\pos(%d,%d)}%02d:%02d:%02d",
                   r.right - 5, r.bottom - 3, hmsf.bHours, hmsf.bMinutes, hmsf.bSeconds);
        rts.Add(str, true, 1, 2, _T("thumbs"));

        rts.Render(spd, 0, 25, bbox);

        BYTE* pData = NULL;
        long size = 0;
        if (!GetDIB(&pData, size)) {
            return;
        }

        BITMAPINFO* bi = (BITMAPINFO*)pData;

        if (bi->bmiHeader.biBitCount != 32) {
            delete [] pData;
            CString strTemp;
            strTemp.Format(IDS_MAINFRM_57, bi->bmiHeader.biBitCount);
            AfxMessageBox(strTemp);
            return;
        }

        int sw = bi->bmiHeader.biWidth;
        int sh = abs(bi->bmiHeader.biHeight);
        int sp = sw * 4;
        const BYTE* src = pData + sizeof(bi->bmiHeader);
        if (bi->bmiHeader.biHeight >= 0) {
            src += sp * (sh - 1);
            sp = -sp;
        }

        int dp = spd.pitch;
        BYTE* dst = (BYTE*)spd.bits + spd.pitch * r.top + r.left * 4;

        for (DWORD h = r.bottom - r.top, y = 0, yd = (sh << 8) / h; h > 0; y += yd, h--) {
            DWORD yf = y & 0xff;
            DWORD yi = y >> 8;

            DWORD* s0 = (DWORD*)(src + (int)yi * sp);
            DWORD* s1 = (DWORD*)(src + (int)yi * sp + sp);
            DWORD* d = (DWORD*)dst;

            for (DWORD w = r.right - r.left, x = 0, xd = (sw << 8) / w; w > 0; x += xd, w--) {
                DWORD xf = x & 0xff;
                DWORD xi = x >> 8;

                DWORD c0 = s0[xi];
                DWORD c1 = s0[xi + 1];
                DWORD c2 = s1[xi];
                DWORD c3 = s1[xi + 1];

                c0 = ((c0 & 0xff00ff) + ((((c1 & 0xff00ff) - (c0 & 0xff00ff)) * xf) >> 8)) & 0xff00ff
                     | ((c0 & 0x00ff00) + ((((c1 & 0x00ff00) - (c0 & 0x00ff00)) * xf) >> 8)) & 0x00ff00;

                c2 = ((c2 & 0xff00ff) + ((((c3 & 0xff00ff) - (c2 & 0xff00ff)) * xf) >> 8)) & 0xff00ff
                     | ((c2 & 0x00ff00) + ((((c3 & 0x00ff00) - (c2 & 0x00ff00)) * xf) >> 8)) & 0x00ff00;

                c0 = ((c0 & 0xff00ff) + ((((c2 & 0xff00ff) - (c0 & 0xff00ff)) * yf) >> 8)) & 0xff00ff
                     | ((c0 & 0x00ff00) + ((((c2 & 0x00ff00) - (c0 & 0x00ff00)) * yf) >> 8)) & 0x00ff00;

                *d++ = c0;
            }

            dst += dp;
        }

        rts.Render(spd, 10000, 25, bbox);

        delete [] pData;
    }

    {
        CRenderedTextSubtitle rts(&csSubLock);
        rts.CreateDefaultStyle(0);
        rts.m_dstScreenSize.SetSize(width, height);
        STSStyle* style = DNew STSStyle();
        style->marginRect.SetRect(margin * 2, margin * 2, margin * 2, height - infoheight - margin);
        rts.AddStyle(_T("thumbs"), style);

        CStringW str;
        str.Format(L"{\\an9\\fs%d\\b1\\bord0\\shad0\\1c&Hffffff&}%s", infoheight - 10, width >= 550 ? L"Media Player Classic" : L"MPC");

        rts.Add(str, true, 0, 1, _T("thumbs"), _T(""), _T(""), CRect(0, 0, 0, 0), -1);

        DVD_HMSF_TIMECODE hmsf = RT2HMS_r(rtDur);

        CPath path(m_wndPlaylistBar.GetCurFileName());
        path.StripPath();
        CStringW fnp = (LPCTSTR)path;

        CStringW fs;
        WIN32_FIND_DATA wfd;
        HANDLE hFind = FindFirstFile(m_wndPlaylistBar.GetCurFileName(), &wfd);
        if (hFind != INVALID_HANDLE_VALUE) {
            FindClose(hFind);

            __int64 size = (__int64(wfd.nFileSizeHigh) << 32) | wfd.nFileSizeLow;
            const int MAX_FILE_SIZE_BUFFER = 65;
            WCHAR szFileSize[MAX_FILE_SIZE_BUFFER];
            StrFormatByteSizeW(size, szFileSize, MAX_FILE_SIZE_BUFFER);
            CString szByteSize;
            szByteSize.Format(_T("%I64d"), size);
            fs.Format(IDS_MAINFRM_58, szFileSize, FormatNumber(szByteSize));
        }

        CStringW ar;
        if (arxy.cx > 0 && arxy.cy > 0 && arxy.cx != wh.cx && arxy.cy != wh.cy) {
            ar.Format(L"(%d:%d)", arxy.cx, arxy.cy);
        }

        str.Format(IDS_MAINFRM_59,
                   fnp, fs, wh.cx, wh.cy, ar, hmsf.bHours, hmsf.bMinutes, hmsf.bSeconds);
        rts.Add(str, true, 0, 1, _T("thumbs"));

        rts.Render(spd, 0, 25, bbox);
    }

    SaveDIB(fn, (BYTE*)dib, dibsize);

    SeekTo(rtPos);

    m_OSD.DisplayMessage(OSD_TOPLEFT, ResStr(IDS_OSD_THUMBS_SAVED), 3000);
}