使用C#對華為IPC攝像頭二次開發（一）

使用C#對華為IPC攝像頭二次開發（二）請訪問：https://www.cnblogs.com/wdw984/p/13572644.html

開發環境：

操作系統：Win10 x64專業版2004

開發工具：VS2019 16.7.2

目標平台：x86，因為要操作內存，所以要打開允許非安全代碼（項目屬性==》生成==》勾選允許不安全代碼）

首先去下載IPC SDK（點擊下載，需要華為授權賬戶。）

新建一個WPF的項目，Framework版本為4.7

把下載的sdk壓縮包中的windows\output32目錄中的HWPuSDK.dll和lib目錄中的所有文件，都復制到項目的bin/debug目錄中（和生成的exe同級），華為的這個SDK對64位支持不好，使用64位遇到不少問題，最終還是先采用32位的DLL。

項目中對圖像的手動處理，經過對比，在Emgu CV和OpenCVSharp4中采用了OpenCVSharp4，個人感覺OpenCVSharp4使用起來更簡潔方便。

項目中對視頻流的回調手動處理展示，采用WriteableBitmap（參考呂毅大神的《WPF 高性能位圖渲染 WriteableBitmap 及其高性能用法示例》），本來想采用D3D這種顯卡加速的方法，無奈沒有找到相關文章和資料，如果哪位大神有資料，還望告知一下。謝謝！

項目中引用了以下組件

在本次開發中，我們先實現自動預覽攝像頭視頻和手動對攝像頭視頻流進行處理。

因為SDK自動播放需要傳入一個控件的句柄，而WPF中窗體上所有控件的句柄都是窗體本身，所以我們還需要使用WindowsFromHost來使用Winform的一些控件來實現播放句柄的傳入。

項目中引用WindowsFromsIntegeration

在項目的MainWindow.xaml中添加三個按鈕、兩個RadioButton、一個Winform的PictureBox和一個WPF的Image控件。大致布局如下：

詳細的xaml代碼：

<Window x:Class="HuaWeiCamera.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:wf="clr-namespace:System.Windows.Forms;assembly=System.Windows.Forms"
        mc:Ignorable="d"
        WindowStartupLocation="CenterScreen"
        Loaded="MainWindow_OnLoaded"
        Title="MainWindow" Height="800" Width="1200" Closed="MainWindow_OnClosed">
    <Grid Margin="0,0,2,0">
        <Grid.RowDefinitions>
            <RowDefinition Height="60"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <WrapPanel VerticalAlignment="Center">
            <StackPanel Margin="30,5,0,0" VerticalAlignment="Center">
                <Button Content="預覽攝像頭" HorizontalAlignment="Center" VerticalAlignment="Center" Width="75" Height="30" Click="ButtonView_OnClick" />
                <WrapPanel Margin="0,5,0,0">
                    <RadioButton Content="自動處理" VerticalAlignment="Center" IsChecked="True" GroupName="PlayMode" x:Name="RadioButtonAuto" />
                    <RadioButton Content="手動處理" VerticalAlignment="Center" GroupName="PlayMode" x:Name="RadioButtonManual" Margin="10,0,0,0" />
                </WrapPanel>
            </StackPanel>
            <Button x:Name="ButtonSaveOne" Content="抓拍一張" HorizontalAlignment="Left" VerticalAlignment="Center" Margin="30,0,0,0" Width="75" Height="30" IsEnabled="False" Click="ButtonSave_OnClick" />
            <Button Content="人臉抓拍" HorizontalAlignment="Left" VerticalAlignment="Center" Margin="30,0,0,0" Width="75" Height="30" />
        </WrapPanel>
        <WrapPanel Grid.Row="1">
            <WindowsFormsHost HorizontalAlignment="Center" Width="1200" Height="700" VerticalAlignment="Center" x:Name="FormsHostVideo">
                <wf:PictureBox x:Name="ImagePlay"></wf:PictureBox>
            </WindowsFormsHost>
            <Image VerticalAlignment="Center" HorizontalAlignment="Center" x:Name="CanvaVideo" Stretch="Fill" Source="{Binding Path=VideoWriteableBitmap}" />

        </WrapPanel>
    </Grid>
</Window>

在App.cs中定義下日志記錄類

    public partial class App : Application
    {
        public static NLog.Logger NewNLog;
        private void App_OnStartup(object sender, StartupEventArgs e)
        {
            DispatcherUnhandledException += App_DispatcherUnhandledException;
            NewNLog = NLog.LogManager.GetLogger("HuaWeiCameraLoger");
        }
    }

根據華為的《SDC 8.0.1 SDK開發指南》，我們要實現攝像頭預覽，需要先定義以下幾個struct和enum：

sturct：PU_REAL_PLAY_INFO_S（視頻實時預覽結構體）、PU_TIME_S（時間結構體）

enum：PU_PROTOCOL_TYPE（傳輸協議類型）、PU_STREAM_TYPE（碼流類型）、PU_VIDEO_TYPE（數據流類型）、PU_MEDIA_CRYPTO_TYPE（加密類型）、PU_MEDIA_CALLBACK_TYPE（回調類型）

using System;
using System.Runtime.InteropServices;
using HuaWeiCamera.Enums;
using HuaWeiCamera.Enums.Media;
using HuaWeiCamera.Enums.Video;

namespace HuaWeiCamera.Struct
{
    /// <summary>
    /// 視頻實時預覽結構體,http://www.cnblogs.com/wdw984
    /// </summary>
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
    public struct PU_REAL_PLAY_INFO_S
    {
        /// <summary>
        /// 設備通道號，一般為101。
        /// </summary>
        public uint ulChannelId;
        /// <summary>
        /// 播放窗口句柄,為IntPtr.Zero表示用戶自己處理視頻數據流，不自動播放視頻流
        /// </summary>
        public IntPtr hPlayWnd;
        /// <summary>
        /// 碼流類型,主碼流、子碼
        /// </summary>
        public PU_STREAM_TYPE enStreamType;
        /// <summary>
        /// 流類型：視頻流、音頻流、復合流、錄 像流、元數據
        /// </summary>
        public PU_VIDEO_TYPE enVideoType;
        /// <summary>
        /// 傳輸協議類型，UDP,TCP
        /// </summary>
        public PU_PROTOCOL_TYPE enProtocolType;
        /// <summary>
        /// 回調類型：0:RTP解密1:RTP不解密 2:Frame 3:YUV
        /// </summary>
        public PU_MEDIA_CALLBACK_TYPE enMediaCallbackType;
        /// <summary>
        /// 請求端IP，第三方平台可以不填，SDK會 自動獲取
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 16)]
        public string szLocalIp;
        /// <summary>
        /// 是否保活
        /// </summary>
        public bool bKeepLive;
        /// <summary>
        /// 請求預錄、錄像開始時間（本地時 間）。 
        /// </summary>
        public PU_TIME_S stStartTime;
        /// <summary>
        /// 請求預錄、錄像結束時間（本地時 間）。 
        /// </summary>
        public PU_TIME_S stEndTime;
        /// <summary>
        /// 加密類型，只支持AES加密。
        /// </summary>
        public PU_MEDIA_CRYPTO_TYPE enMediaCryptoType;
        /// <summary>
        /// 加密密鑰
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 44)]
        public string szMediaCrypto;
        /// <summary>
        /// szReserved[0-15]表示組播IP地址
        /// szReserved[16-19]表示組播端口
        /// szReserved[22]表示智能分析數據打包 格式 0:XML,1:元數據
        /// szReserved[23]表示元數據請求類型，取值參考枚舉 PU_METADATA_REQUEST_TYPE_E定義
        /// </summary>
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 32)]
        public byte[] szReserved;
    }
}

namespace HuaWeiCamera.Enums
{
    /// <summary>
    /// 視頻流類型,http://www.cnblogs.com/wdw984
    /// </summary>
    public enum PU_STREAM_TYPE
    {
        /// <summary>
        /// 視頻主碼流
        /// </summary>
        PU_VIDEO_MAIN_STREAM=0,
        /// <summary>
        /// 視頻子碼流
        /// </summary>
        PU_VIDEO_SUB_STREAM1,
        /// <summary>
        /// 視頻子碼流2（VWareC01 不支持）
        /// </summary>
        PU_VIDEO_SUB_STREAM2,
        /// <summary>
        /// 視頻子碼流3（VWareC01 不支持）
        /// </summary>
        PU_VIDEO_SUB_STREAM3,
        /// <summary>
        /// 視頻子碼流4
        /// </summary>
        PU_VIDEO_SUB_STREAM4,
        /// <summary>
        /// 視頻子碼流5
        /// </summary>
        PU_VIDEO_SUB_STREAM5,
        /// <summary>
        /// 預留值
        /// </summary>
         PU_VIDEO_STREAM_MAX
    }
}

namespace HuaWeiCamera.Enums.Video
{
    /// <summary>
    /// 碼流類型,http://www.cnblogs.com/wdw984
    /// </summary>
    public enum PU_VIDEO_TYPE
    {
        /// <summary>
        /// 視頻流
        /// </summary>
        PU_VIDEO_TYPE_VIDEO = 0,
        /// <summary>
        /// 音頻流
        /// </summary>
        PU_VIDEO_TYPE_AUDIO,
        /// <summary>
        /// 復合流
        /// </summary>
        PU_VIDEO_TYPE_MUX, 
        /// <summary>
        /// 錄像流
        /// </summary>
        PU_VIDEO_TYPE_RECORD, 
        /// <summary>
        /// 元數據流
        /// </summary>
        PU_VIDEO_TYPE_META, 
        /// <summary>
        /// 視頻+元數據流
        /// </summary>
        PU_VIDEO_TYPE_VIDEO_META, 
        /// <summary>
        /// 預留值
        /// </summary>
        PU_VIDEO_TYPE_MAX
    }
}

namespace HuaWeiCamera.Enums
{
    /// <summary>
    /// 數據傳輸類型,http://www.cnblogs.com/wdw984
    /// </summary>
    public enum PU_PROTOCOL_TYPE
    {
        /// <summary>
        /// UDP
        /// </summary>
        PU_PROTOCOL_TYPE_UDP = 0, 
        /// <summary>
        /// TCP
        /// </summary>
        PU_PROTOCOL_TYPE_TCP,
        /// <summary>
        /// 組播方式
        /// </summary>
        PU_PROTOCOL_TYPE_MULTICAST,
        /// <summary>
        /// 預留值
        /// </summary>
        PU_PROTOCOL_TYPE_MAX
    }
}

namespace HuaWeiCamera.Enums.Media
{
    /// <summary>
    /// 媒體回調類型,http://www.cnblogs.com/wdw984
    /// </summary>
    public enum PU_MEDIA_CALLBACK_TYPE
    {
        /// <summary>
        /// RTP包方式
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_RTP = 0, 
        /// <summary>
        /// RTP包形式，不解密
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_RTP_CRYPTO, 
        /// <summary>
        /// 幀回調方式
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_FRAME, 
        /// <summary>
        /// YUV方式，Linux不支持
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_YUV, 
        /// <summary>
        /// 把RTP包回調給控件方處理方式，Linux不支持
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_FOR_STORAGE, 
        /// <summary>
        /// 智能元數據方式
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_META_FRAME, 
        /// <summary>
        /// 預留值
        /// </summary>
        PU_MEDIA_CALLBACK_TYPE_MAX
    }
}

using System.Runtime.InteropServices;

namespace HuaWeiCamera.Struct
{
    /// <summary>
    /// 時間結構體，http://www.cnblogs.com/wdw984
    /// </summary>
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
    public struct PU_TIME_S
    {
        /// <summary>
        /// 年
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 5)]
        public string szYear;
        /// <summary>
        /// 月
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)]
        public string szMonth;
        /// <summary>
        /// 日
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)]
        public string szDay;
        /// <summary>
        /// 時
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)]
        public string szHour;
        /// <summary>
        /// 分
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)]
        public string szMinute;
        /// <summary>
        /// 秒
        /// </summary>
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)]
        public string szSecond;
    }
}

定義一個靜態類，用來實現調用SDK和攝像頭交互（HuaWeiSDKHelper）

using System;
using System.Runtime.InteropServices;
using HuaWeiCamera.Enums;
using HuaWeiCamera.Enums.SnapShot;
using HuaWeiCamera.Struct;

namespace HuaWeiCamera.Class
{
    /// <summary>
    /// 華為HoloSens SDC二次開發使用，http://www.cnblogs.com/wdw984
    /// </summary>
    public static class HuaWeiSdkHelper
    {
        private const string SdkPath= "HWPuSDK.dll";
        #region 初始化和登錄

        /// <summary>
        /// 初始化設備
        /// </summary>
        /// <param name="ulLinkMode">0自動 1手動 3混合模式</param>
        /// <param name="szLocalIp">本地IP</param>
        /// <param name="ulLocalPort">本地端口</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_Init", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool IVS_Pu_Init(uint ulLinkMode, string szLocalIp, uint ulLocalPort);
        /// <summary>
        /// 遠程登錄設備
        /// </summary>
        /// <param name="szLoginIp">設備IP</param>
        /// <param name="ulLoginPort">設備端口 6060</param>
        /// <param name="szUserName">登錄名 ApiAdmin</param>
        /// <param name="szPasswd">登錄密碼 HuaWei123</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_Login", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        public static extern uint IVS_PU_Login(string szLoginIp, uint ulLoginPort, string szUserName, string szPasswd);

        /// <summary>
        /// 初始化和登錄設備
        /// </summary>
        /// <param name="sdcIp">SDC設備IP</param>
        /// <param name="sdcPort">SDC設備端口</param>
        /// <param name="sdcUser">SDC登錄用戶名</param>
        /// <param name="sdcPwd">SDC登錄密碼</param>
        /// <param name="errMsg">失敗時的錯誤信息</param>
        /// <param name="ulIdentifyId">登錄成功后返回登錄句柄</param>
        public static void InitAndLogin(string sdcIp,uint sdcPort,string sdcUser,string sdcPwd,out uint ulIdentifyId,out string errMsg)
        {
            ulIdentifyId = 0;
            errMsg = "";
            //要開啟TLS的情況時：初始化調用IVS_PU_InitEx接口，登錄調用IVS_PU_Login 接口時端口號設置為6061
            if (!IVS_Pu_Init(1, "192.168.2.144", 6060))
            {
                errMsg=($"設備初始化失敗，{GetLastErrorInfo()}");
                return;
            }
            ulIdentifyId = IVS_PU_Login(sdcIp, sdcPort, sdcUser, sdcPwd);
            if (ulIdentifyId == 0)
            {
                errMsg=$"設備登錄失敗，{GetLastErrorInfo()}";
            }
        }

        #endregion

        #region 預覽相關
        /// <summary>
        /// 實時預覽
        /// </summary>
        /// <param name="ulIdentifyId">登錄成功后返回的用戶編號</param>
        /// <param name="pstRealPlayInfo">播放結構體</param>
        /// <param name="fRealDataCallBack">回調實現播放</param>
        /// <param name="pUsrData">傳入碼流數據 回調函數作為參數</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_RealPlay")]
        public static extern uint IVS_PU_RealPlay(uint ulIdentifyID, PU_REAL_PLAY_INFO_S[] pstRealPlayInfo, PfRealDataCallBack fRealDataCallBack, ref IntPtr pUsrData);

        public delegate void PfRealDataCallBack(IntPtr szBuffer, int lSize, IntPtr pUsrData);
        /// <summary>
        /// 停止實時預覽
        /// </summary>
        /// <param name="ulIdentifyId">登錄成功后返回的用戶編號</param>
        /// <param name="ulRealHandle">實時播放句柄</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_StopRealPlay", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        public static extern uint IVS_PU_StopRealPlay(uint ulIdentifyId, uint ulRealHandle);
        #endregion

        #region 錯誤信息相關

        /// <summary>
        /// 獲取最后一次錯誤代碼
        /// </summary>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_GetLastError", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        private static extern int IVS_PU_GetLastError();

        /// <summary>
        /// 根據錯誤代碼返回錯誤信息
        /// </summary>
        /// <param name="ulErrorNo">錯誤編號</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_GetErrorMsg", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        private static extern IntPtr IVS_PU_GetErrorMsg(int ulErrorNo);

        /// <summary>
        /// 返回最后一次錯誤碼和錯誤信息
        /// </summary>
        /// <returns></returns>
        public static string GetLastErrorInfo()
        {
            var lastErrorCode = IVS_PU_GetLastError();
            var lastErrorMsg = Marshal.PtrToStringAnsi(IVS_PU_GetErrorMsg(lastErrorCode));

            return $"錯誤碼：{IVS_PU_GetLastError()}，錯誤信息：{lastErrorMsg}";
        }

        #endregion
        
        #region 退出登錄

        /// <summary>
        /// 退出登錄
        /// </summary>
        /// <param name="ulIdentifyId">登錄成功后返回的句柄編號</param>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_Logout", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool IVS_PU_Logout(uint ulIdentifyId);
        /// <summary>
        /// 反注冊設備，退出時進行設備釋放
        /// </summary>
        /// <returns></returns>
        [DllImport(SdkPath, EntryPoint = "IVS_PU_Cleanup", CharSet = CharSet.Ansi, SetLastError = true, PreserveSig = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool IVS_PU_Cleanup();

        #endregion

    }
}

定義一個繼承了INotifyPropertyChanged的Model，用來實現刷新Image控件

    public class VideoYuvModelView : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        private WriteableBitmap bitmapImage { get; set; }

        public WriteableBitmap VideoWriteableBitmap
        {
            get => bitmapImage;
            set
            {
                bitmapImage = value;
                PropertyChanged?.Invoke(this,new PropertyChangedEventArgs("VideoBitmapImage"));
            }
        }
    }

在MainWindow.cs中我們需要定義一些變量：

        private uint _ulIdentifyId;//登錄攝像頭后返回的編號
        private uint _ulRealHandleId;//調用預覽SDK返回的結果值
        private static bool _isSave;//是否保存當前幀為圖片
        private static bool _isExit;//是否退出
        private static HuaWeiSdkHelper.PfRealDataCallBack _fedRealPlayCallbackWithYUV;//手動處理攝像頭回調時的委托事件
        private const uint ByteLength = 1920 * 1080 * 4;//位圖的大小
        private static readonly VideoYuvModelView VideoYuvModelView = new VideoYuvModelView();//Image的數據源，用來手動處理視頻時候展示圖像
        private IntPtr _videoPlayHandle = IntPtr.Zero;//自動預覽時的控件句柄

        [DllImport("kernel32.dll")]
        private static extern void CopyMemory(IntPtr destination, IntPtr source, uint length);//用來復制內存中的數據

在窗體初始化和加載事件中，我們來初始化一些數據的綁定

public MainWindow()
        {
            InitializeComponent();
            VideoYuvModelView.VideoWriteableBitmap = new WriteableBitmap(1920, 1800, 96.0, 96.0, PixelFormats.Bgr32, null);//因為攝像頭返回的圖片大小時1920*1080，所以這里定義的大小要和返回的圖片大小一致
        }

        private void MainWindow_OnLoaded(object sender, RoutedEventArgs e)
        {
            CanvaVideo.DataContext = VideoYuvModelView;//手動處理時，Image控件數據源
            _videoPlayHandle = ImagePlay.Handle;//自動處理時，使用Winform的控件句柄
        }

預覽攝像頭按鈕事件，中間根據選中的自動處理和手動處理來分別做出不同的相應

#region 視頻預覽（自動和手動處理視頻流）

        private void ButtonView_OnClick(object sender, RoutedEventArgs e)
        {
            if (0 == _ulIdentifyId)
            {
                //這里通過網絡登錄到攝像頭，具體端口、用戶名、密碼請參考開發手冊
                HuaWeiSdkHelper.InitAndLogin("192.168.2.250", 6060, "ApiAdmin", "HuaWei123", out _ulIdentifyId, out string errMsg);

                if (0 == _ulIdentifyId)
                {
                    MessageBox.Show(errMsg);
                    return;
                }
            }
            var prpInfos = new PU_REAL_PLAY_INFO_S[1];
            var clientInfo = new PU_REAL_PLAY_INFO_S
            {
                ulChannelId = 101,
                hPlayWnd = _videoPlayHandle,
                enProtocolType = PU_PROTOCOL_TYPE.PU_PROTOCOL_TYPE_TCP,
                enStreamType = PU_STREAM_TYPE.PU_VIDEO_MAIN_STREAM,
                enVideoType = PU_VIDEO_TYPE.PU_VIDEO_TYPE_VIDEO,
                enMediaCryptoType = PU_MEDIA_CRYPTO_TYPE.PU_MEDIA_CRYPTO_NONE,
                enMediaCallbackType = PU_MEDIA_CALLBACK_TYPE.PU_MEDIA_CALLBACK_TYPE_RTP,
                szReserved = new byte[32],
                bKeepLive = true
            };

            IntPtr pUsrData = (IntPtr)_ulIdentifyId;
            if (RadioButtonManual.IsChecked == true)
            {
                //手動處理視頻預覽
                FormsHostVideo.Visibility = Visibility.Collapsed;
                CanvaVideo.Visibility = Visibility.Visible;
                clientInfo.hPlayWnd = IntPtr.Zero;
                clientInfo.enMediaCallbackType = PU_MEDIA_CALLBACK_TYPE.PU_MEDIA_CALLBACK_TYPE_YUV;
                prpInfos[0] = clientInfo;
                _fedRealPlayCallbackWithYUV = FedRealPlayCallbackWithYUV; //手動處理回調
                _ulRealHandleId = HuaWeiSdkHelper.IVS_PU_RealPlay(_ulIdentifyId, prpInfos, _fedRealPlayCallbackWithYUV, ref pUsrData);
                if (0 == _ulRealHandleId)
                {
                    MessageBox.Show(HuaWeiSdkHelper.GetLastErrorInfo());
                }

                ButtonSaveOne.IsEnabled = true;//點擊 抓拍一張 按鈕，會把_isSave變量設置為true，從而在回調事件中可以保存當前幀為圖片
            }
            else
            {
                ButtonSaveOne.IsEnabled = false;
                CanvaVideo.Visibility = Visibility.Collapsed;
                FormsHostVideo.Visibility = Visibility.Visible;
                prpInfos[0] = clientInfo;
                //傳入句柄，自動預覽
                _ulRealHandleId = HuaWeiSdkHelper.IVS_PU_RealPlay(_ulIdentifyId, prpInfos, null, ref pUsrData);
                if (0 == _ulRealHandleId)
                {
                    MessageBox.Show(HuaWeiSdkHelper.GetLastErrorInfo());
                }
            }
        }

        #region 手動解析YUV數據並展示在界面上
        private static void FedRealPlayCallbackWithYUV(IntPtr szBuffer, int lSize, IntPtr pUsrData)
        {
            if (_isExit) return;
            try
            {

                Span<byte> nativeSpan;
                unsafe
                {
                    nativeSpan = new Span<byte>(szBuffer.ToPointer(), lSize);
                }

                if (nativeSpan.Length > 0)
                {
                    #region 處理視頻流YUV圖像

                    Mat yuvImg = new Mat(1080 * 3 / 2, 1920, MatType.CV_8UC1);
                    Mat rgbImg = new Mat(1080, 1920, MatType.CV_8UC1);

                    Marshal.Copy(nativeSpan.ToArray(), 0, yuvImg.Data, nativeSpan.Length);
                    Cv2.CvtColor(yuvImg, rgbImg, ColorConversionCodes.YUV2RGBA_I420);
                    Application.Current.Dispatcher?.InvokeAsync(() =>
                    {
                        VideoYuvModelView.VideoWriteableBitmap.Lock();
                        unsafe
                        {
                            CopyMemory(VideoYuvModelView.VideoWriteableBitmap.BackBuffer, new IntPtr(rgbImg.DataPointer), ByteLength);
                        }
                        VideoYuvModelView.VideoWriteableBitmap.AddDirtyRect(new Int32Rect(0, 0, 1920, 1080));
                        VideoYuvModelView.VideoWriteableBitmap.Unlock();
                    });

                    if (_isSave)
                    {
                        Cv2.ImWrite(Path.Combine($"{AppDomain.CurrentDomain.BaseDirectory}", "jpg",$"{Guid.NewGuid()}.jpg"), rgbImg);
                        _isSave = false;
                    }

                    #endregion
                }
            }
            catch (Exception e)
            {
                App.NewNLog.Error($"解析視頻流出錯：{e}");
            }
        }
        #endregion

        #endregion

在程序關閉的時候進行資源釋放。

        private void MainWindow_OnClosed(object sender, EventArgs e)
        {
            _isExit = true;if (_ulRealHandleId > 0)
            {
                HuaWeiSdkHelper.IVS_PU_StopRealPlay(_ulIdentifyId, _ulRealHandleId);//停止預覽
            }
            if (_ulIdentifyId > 0)
            {
                HuaWeiSdkHelper.IVS_PU_Logout(_ulIdentifyId);//退出登錄
            }
            HuaWeiSdkHelper.IVS_PU_Cleanup();//SDK資源釋放
        }

具體效果如下：

1、自動預覽

2、手動處理

但是這里的YUV回調填充到WriteableBitmap遇到個問題，就是無法填滿WriteableBitmap（把WriteableBitmap中的數據保存下來也是和預覽的效果一樣，估計是填充的算法不對），只能填充一部分，這里涉及到本人的知識盲區，暫時沒法解決掉。

3、一幀圖像保存為本地圖片

 

 

至此我們使用C#初步實現了華為IPC攝像頭的預覽和數據流處理（也可以把處理類型換成視頻流，然后存本地視頻文件，因為默認時h265編碼格式，播放時使用PotPlayer播放器來播放），算是入門了。

下一章我們將實現調用SDK來實現人臉自動抓拍效果。