dsutils.cs

DirectShowLibV1-5針對DirectShow一些函數以及指令和LIB的檔案

                catch
                {
                }

                return s;
            }
        }

        /// <summary>
        /// Returns an array of DsDevices of type devcat.
        /// </summary>
        /// <param name="cat">Any one of FilterCategory</param>
        public static DsDevice[] GetDevicesOfCat(Guid FilterCategory)
        {
            int hr;

            // Use arrayList to build the retun list since it is easily resizable
            DsDevice[] devret;
            ArrayList devs = new ArrayList();
#if USING_NET11
            UCOMIEnumMoniker enumMon;
#else
            IEnumMoniker enumMon;
#endif

            ICreateDevEnum enumDev = (ICreateDevEnum)new CreateDevEnum();
            hr = enumDev.CreateClassEnumerator(FilterCategory, out enumMon, 0);
            DsError.ThrowExceptionForHR(hr);

            // CreateClassEnumerator returns null for enumMon if there are no entries
            if (hr != 1)
            {
                try
                {
                    try
                    {
#if USING_NET11
                        UCOMIMoniker[] mon = new UCOMIMoniker[1];
#else
                        IMoniker[] mon = new IMoniker[1];
#endif

#if USING_NET11
                        int j;
                        while ((enumMon.Next(1, mon, out j) == 0))
#else
                        while ((enumMon.Next(1, mon, IntPtr.Zero) == 0))
#endif
                        {
                            try
                            {
                                // The devs array now owns this object.  Don't
                                // release it if we are going to be successfully
                                // returning the devret array
                                devs.Add(new DsDevice(mon[0]));
                            }
                            catch
                            {
                                Marshal.ReleaseComObject(mon[0]);
                                throw;
                            }
                        }
                    }
                    finally
                    {
                        Marshal.ReleaseComObject(enumMon);
                    }

                    // Copy the ArrayList to the DsDevice[]
                    devret = new DsDevice[devs.Count];
                    devs.CopyTo(devret);
                }
                catch
                {
                    foreach (DsDevice d in devs)
                    {
                        d.Dispose();
                    }
                    throw;
                }
            }
            else
            {
                devret = new DsDevice[0];
            }

            return devret;
        }

        /// <summary>
        /// Get the FriendlyName for a moniker
        /// </summary>
        /// <returns>String or null on error</returns>
        private string GetFriendlyName()
        {
            IPropertyBag bag = null;
            string ret = null;
            object bagObj = null;
            object val = null;

            try
            {
                Guid bagId = typeof (IPropertyBag).GUID;
                m_Mon.BindToStorage(null, null, ref bagId, out bagObj);

                bag = (IPropertyBag) bagObj;

                int hr = bag.Read("FriendlyName", out val, null);
                DsError.ThrowExceptionForHR(hr);

                ret = val as string;
            }
            catch
            {
                ret = null;
            }
            finally
            {
                bag = null;
                if (bagObj != null)
                {
                    Marshal.ReleaseComObject(bagObj);
                    bagObj = null;
                }
            }

            return ret;
        }

        public void Dispose()
        {
            if (Mon != null)
            {
                Marshal.ReleaseComObject(Mon);
                m_Mon = null;
                GC.SuppressFinalize(this);
            }
            m_Name = null;
        }
    }


    sealed public class DsFindPin
    {
        private DsFindPin()
        {
            // Prevent people from trying to instantiate this class
        }

        /// <summary>
        /// Scans a filter's pins looking for a pin in the specified direction
        /// </summary>
        /// <param name="vSource">The filter to scan</param>
        /// <param name="vDir">The direction to find</param>
        /// <param name="iIndex">Zero based index (ie 2 will return the third pin in the specified direction)</param>
        /// <returns>The matching pin, or null if not found</returns>
        public static IPin ByDirection(IBaseFilter vSource, PinDirection vDir, int iIndex)
        {
            int hr;
            int lFetched;
            IEnumPins ppEnum;
            PinDirection ppindir;
            IPin pRet = null;
            IPin[] pPins = new IPin[1];

            if (vSource == null)
            {
                return null;
            }

            // Get the pin enumerator
            hr = vSource.EnumPins(out ppEnum);
            DsError.ThrowExceptionForHR(hr);

            try
            {
                // Walk the pins looking for a match
                while ((ppEnum.Next(1, pPins, out lFetched) >= 0) && (lFetched == 1))
                {
                    // Read the direction
                    hr = pPins[0].QueryDirection(out ppindir);
                    DsError.ThrowExceptionForHR(hr);

                    // Is it the right direction?
                    if (ppindir == vDir)
                    {
                        // Is is the right index?
                        if (iIndex == 0)
                        {
                            pRet = pPins[0];
                            break;
                        }
                        iIndex--;
                    }
                    Marshal.ReleaseComObject(pPins[0]);
                }
            }
            finally
            {
                Marshal.ReleaseComObject(ppEnum);
            }

            return pRet;
        }

        /// <summary>
        /// Scans a filter's pins looking for a pin with the specified name
        /// </summary>
        /// <param name="vSource">The filter to scan</param>
        /// <param name="vPinName">The pin name to find</param>
        /// <returns>The matching pin, or null if not found</returns>
        public static IPin ByName(IBaseFilter vSource, string vPinName)
        {
            int hr;
            int lFetched;
            IEnumPins ppEnum;
            PinInfo ppinfo;
            IPin pRet = null;
            IPin[] pPins = new IPin[1];

            if (vSource == null)
            {
                return null;
            }

            // Get the pin enumerator
            hr = vSource.EnumPins(out ppEnum);
            DsError.ThrowExceptionForHR(hr);

            try
            {
                // Walk the pins looking for a match
                while ((ppEnum.Next(1, pPins, out lFetched) >= 0) && (lFetched == 1))
                {
                    // Read the info
                    hr = pPins[0].QueryPinInfo(out ppinfo);
                    DsError.ThrowExceptionForHR(hr);

                    // Is it the right name?
                    if (ppinfo.name == vPinName)
                    {
                        DsUtils.FreePinInfo(ppinfo);
                        pRet = pPins[0];
                        break;
                    }
                    Marshal.ReleaseComObject(pPins[0]);
                    DsUtils.FreePinInfo(ppinfo);
                }
            }
            finally
            {
                Marshal.ReleaseComObject(ppEnum);
            }

            return pRet;
        }

        /// <summary>
        /// Scan's a filter's pins looking for a pin with the specified category
        /// </summary>
        /// <param name="vSource">The filter to scan</param>
        /// <param name="guidPinCat">The guid from PinCategory to scan for</param>
        /// <param name="iIndex">Zero based index (ie 2 will return the third pin of the specified category)</param>
        /// <returns>The matching pin, or null if not found</returns>
        public static IPin ByCategory(IBaseFilter vSource, Guid PinCategory, int iIndex)
        {
            int hr;
            int lFetched;
            IEnumPins ppEnum;
            IPin pRet = null;
            IPin[] pPins = new IPin[1];

            if (vSource == null)
            {
                return null;
            }

            // Get the pin enumerator
            hr = vSource.EnumPins(out ppEnum);
            DsError.ThrowExceptionForHR(hr);

            try
            {
                // Walk the pins looking for a match
                while ((ppEnum.Next(1, pPins, out lFetched) >= 0) && (lFetched == 1))
                {
                    // Is it the right category?
                    if (DsUtils.GetPinCategory(pPins[0]) == PinCategory)
                    {
                        // Is is the right index?
                        if (iIndex == 0)
                        {
                            pRet = pPins[0];
                            break;
                        }
                        iIndex--;
                    }
                    Marshal.ReleaseComObject(pPins[0]);
                }
            }
            finally
            {
                Marshal.ReleaseComObject(ppEnum);
            }

            return pRet;
        }
        /// <summary>
        /// Scans a filter's pins looking for a pin with the specified connection status
        /// </summary>
        /// <param name="vSource">The filter to scan</param>
        /// <param name="vStat">The status to find (connected/unconnected)</param>
        /// <param name="iIndex">Zero based index (ie 2 will return the third pin with the specified status)</param>
        /// <returns>The matching pin, or null if not found</returns>
        public static IPin ByConnectionStatus(IBaseFilter vSource, PinConnectedStatus vStat, int iIndex)
        {
            int hr;
            int lFetched;
            IEnumPins ppEnum;
            IPin pRet = null;
            IPin pOutPin;
            IPin[] pPins = new IPin[1];

            if (vSource == null)
            {
                return null;
            }

            // Get the pin enumerator
            hr = vSource.EnumPins(out ppEnum);
            DsError.ThrowExceptionForHR(hr);

            try
            {
                // Walk the pins looking for a match
                while ((ppEnum.Next(1, pPins, out lFetched) >= 0) && (lFetched == 1))
                {
                    // Read the connected status
                    hr = pPins[0].ConnectedTo(out pOutPin);

                    // Check for VFW_E_NOT_CONNECTED.  Anything else is bad.
                    if (hr != DsResults.E_NotConnected)
                    {
                        DsError.ThrowExceptionForHR(hr);