Question

using System;
using System.Runtime.InteropServices;
using System.Drawing;
using System.Drawing.Imaging;
using System.Windows.Forms;

namespace ScreenShotDemo
{
    public class ScreenCapture
    {



        [StructLayout(LayoutKind.Sequential)]
        struct CURSORINFO
        {
            public Int32 cbSize;
            public Int32 flags;
            public IntPtr hCursor;
            public POINTAPI ptScreenPos;
        }

        [StructLayout(LayoutKind.Sequential)]
        struct POINTAPI
        {
            public int x;
            public int y;
        }

        [DllImport("user32.dll")]
        static extern bool GetCursorInfo(out CURSORINFO pci);

        [DllImport("user32.dll")]
        static extern bool DrawIcon(IntPtr hDC, int X, int Y, IntPtr hIcon);

        const Int32 CURSOR_SHOWING = 0x00000001;

        public static Bitmap CaptureScreen(bool CaptureMouse)
        {
            Bitmap result = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, PixelFormat.Format32bppArgb);

            try
            {
                using (Graphics g = Graphics.FromImage(result))
                {
                    g.CopyFromScreen(0, 0, 0, 0, Screen.PrimaryScreen.Bounds.Size, CopyPixelOperation.SourceCopy);

                    if (CaptureMouse)
                    {
                        CURSORINFO pci;
                        pci.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(typeof(CURSORINFO));

                        if (GetCursorInfo(out pci))
                        {
                            if (pci.flags == CURSOR_SHOWING)
                            {
                                DrawIcon(g.GetHdc(), pci.ptScreenPos.x, pci.ptScreenPos.y, pci.hCursor);
                                g.ReleaseHdc();
                            }
                        }
                    }
                }
            }
            catch
            {
                result = null;
            }

            return result;
        }
    }

我的电脑上有6GB的内存RAM，所以它永远不会到达null部分。但是我的兄弟只有2GB的内存，他到了零部分。

我的程序使用此代码每隔40ms使用Form1中的计时器截取屏幕截图：

private void timer1_Tick(object sender, EventArgs e)
        {
            {
            using (bitmap = (Bitmap)ScreenCapture.CaptureScreen(true))            
            ffmp.PushFrame(bitmap);

            }  

        }

我该怎么做才能解决这个问题？为什么会这样？

这是我的ffmpeg课程：

using System;
using System.Windows.Forms;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;
using System.IO.Pipes;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.IO;
using DannyGeneral;

namespace ScreenVideoRecorder
{
    class Ffmpeg
    {
        NamedPipeServerStream p;
        String pipename = "mytestpipe";
        byte[] b;
        System.Diagnostics.Process process;
        string ffmpegFileName = "ffmpeg.exe";
        string workingDirectory;

        public Ffmpeg()
        {
            workingDirectory = Path.GetDirectoryName(Application.ExecutablePath);//System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetEntryAssembly().Location);//Application.StartupPath; //Path.GetDirectoryName(Application.ExecutablePath);// +@"\workingDirectory";
            Logger.Write("workingDirectory: " + workingDirectory);
            if (!Directory.Exists(workingDirectory))
            {
                Directory.CreateDirectory(workingDirectory);
            }
            ffmpegFileName = Path.Combine(workingDirectory, ffmpegFileName);//@"\ffmpeg.exe";
            Logger.Write("FfmpegFilename: " + ffmpegFileName);
        }

        public void Start(string pathFileName, int BitmapRate)
        {
            try
            {
                string outPath = pathFileName;
                Logger.Write("Output Video File Directory: " + outPath);
                Logger.Write("Frame Rate: " + BitmapRate.ToString());
                p = new NamedPipeServerStream(pipename, PipeDirection.Out, 1, PipeTransmissionMode.Byte);
                b = new byte[1920 * 1080 * 3]; // some buffer for the r g and b of pixels of an image of size 720p

                ProcessStartInfo psi = new ProcessStartInfo();
                psi.WindowStyle = ProcessWindowStyle.Hidden;
                psi.UseShellExecute = false;
                psi.CreateNoWindow = true;
                psi.FileName = ffmpegFileName;
                Logger.Write("psi.FileName: " + psi.FileName);
                psi.WorkingDirectory = workingDirectory;
                Logger.Write("psi.WorkingDirectory: " + psi.WorkingDirectory);
                psi.Arguments = @"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \\.\pipe\mytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + outPath;
                Logger.Write("ProcessStartInfo Arguments" + @"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \\.\pipe\mytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + outPath);
                //psi.RedirectStandardOutput = true;
                process = Process.Start(psi);
                process.EnableRaisingEvents = false;
                p.WaitForConnection();
            }
            catch (Exception err)
            {
                Logger.Write("Exception Error: " + err.ToString());
            }
        }

        public void PushFrame(Bitmap bmp)
        {
            try
            {
                int length;
                // Lock the bitmap's bits.
                //bmp = new Bitmap(1920, 1080);
                Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
                //Rectangle rect = new Rectangle(0, 0, 1280, 720);
                System.Drawing.Imaging.BitmapData bmpData =
                    bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly,
                    bmp.PixelFormat);

                int absStride = Math.Abs(bmpData.Stride);
                // Get the address of the first line.
                IntPtr ptr = bmpData.Scan0;

                // Declare an array to hold the bytes of the bitmap.
                //length = 3 * bmp.Width * bmp.Height;
                length = absStride * bmpData.Height;
                byte[] rgbValues = new byte[length];

                //Marshal.Copy(ptr, rgbValues, 0, length);
                int j = bmp.Height - 1;
                for (int i = 0; i < bmp.Height; i++)
                {
                    IntPtr pointer = new IntPtr(bmpData.Scan0.ToInt32() + (bmpData.Stride * j));
                    System.Runtime.InteropServices.Marshal.Copy(pointer, rgbValues, absStride * (bmp.Height - i - 1), absStride);
                    j--;
                }
                p.Write(rgbValues, 0, length);
                bmp.UnlockBits(bmpData);
            }
            catch(Exception err)
            {
                Logger.Write("Error: " + err.ToString());
            }

我每隔40ms在Form1中截取一个屏幕截图，然后将位图推送到ffmpeg类中的Pipe。 ffmpeg.exe以参数启动一次，然后等待连接。

当我在任务管理器上查看时，我发现ffmpeg.exe以800-900mb的内存开始，并且非常快速地跳转到1020或更多mb的内存。

我应该如何处理像我哥哥这样的用户只有2GB内存的情况？当他内存不足时，屏幕捕获类会向他返回null并且程序崩溃。

修改

我更改了测试计时器代码：

private void timer1_Tick(object sender, EventArgs e)
        {           
            Image mScreenImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
            ffmp.PushFrame((Bitmap)mScreenImage);
            mScreenImage.Dispose();

        }

所以现在我在没有连接到屏幕捕获类的情况下获取屏幕的一个屏幕截图，并将每个40ms的图像发送到管道。我在任务管理器中看到ffmpeg.exe超过1GB的内存。所以难怪我的兄弟如果在他的电脑上只有2gb ram就有问题。

为什么ffmpeg.exe会占用这么多内存？泄漏？
我该怎么处理？

Answer 1

如果您想知道为什么发生异常，我建议您处理捕获中发现的任何异常。

所以而不是

catch 
{  
  result = null; 
}

试

catch (Exception ex) 
{
   // log the value of ex.ToString() to a file, the screen, something.
   System.IO.File.AppendAllText("debug.log",ex.ToString());
   result = null;
}

我使用这个屏幕截图代码截取屏幕截图，但有时它返回null为什么？

1 个答案: