C# Windows窗体vs Unity3D HttpWebRequest性能

我正在做一个简单的程序，从一个远程IP摄像头抓取图像。经过几天的研究，我能够从MJPEG实时流中提取JPEG图像，并使用我得到的示例代码

我用Windows窗体做了一个原型。使用Windows窗体，我每10秒从IP摄像头接收80张图像

现在，我将代码移植到Unity3D，每10秒获得2帧

所以基本上大约有78张图像没有被接收到。

---

这东西看起来像中世纪的幻灯片放映

bool keepRunning = true;
    private void Decode_MJPEG_Images(string streamTestURL = null)
    {
        keepRunning = true;
        streamTestURL = "http://64.122.208.241:8000/axis-cgi/mjpg/video.cgi?resolution=320x240"; //For Testing purposes only

        // create HTTP request
        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(streamTestURL);
        // get response
        WebResponse resp = req.GetResponse();

        System.IO.Stream imagestream = resp.GetResponseStream();

        const int BufferSize = 5000000;
        byte[] imagebuffer = new byte[BufferSize];
        int a = 2;
        int framecounter = 0;
        int startreading = 0;
        byte[] start_checker = new byte[2];
        byte[] end_checker = new byte[2];

        while (keepRunning)
        {
            start_checker[1] = (byte)imagestream.ReadByte();
            end_checker[1] = start_checker[1];

            //This if statement searches for the JPEG header, and performs the relevant operations
            if (start_checker[0] == 0xff && start_checker[1] == 0xd8)// && Reset ==0)
            {
                Array.Clear(imagebuffer, 0, imagebuffer.Length);
                //Rebuild jpeg header into imagebuffer
                imagebuffer[0] = 0xff;
                imagebuffer[1] = 0xd8;
                a = 2;
                framecounter++;
                startreading = 1;
            }

            //This if statement searches for the JPEG footer, and performs the relevant operations
            if (end_checker[0] == 0xff && end_checker[1] == 0xd9)
            {
                startreading = 0;
                //Write final part of JPEG header into imagebuffer
                imagebuffer[a] = start_checker[1];
                System.IO.MemoryStream jpegstream = new System.IO.MemoryStream(imagebuffer);

                Debug.Log("Received Full Image");
                Debug.Log(framecounter.ToString());


                //Display Image
            }

            //This if statement fills the imagebuffer, if the relevant flags are set
            if (startreading == 1 && a < BufferSize)
            {
                imagebuffer[a] = start_checker[1];
                a++;
            }

            //Catches error condition where a = buffer size - this should not happen in normal operation
            if (a == BufferSize)
            {
                a = 2;
                startreading = 0;
            }

            start_checker[0] = start_checker[1];
            end_checker[0] = end_checker[1];

        }


        resp.Close();
    }

我正在新线程中运行函数，就像在Windows窗体中一样。我最初认为Unity中的问题是因为我正在显示图像，但它不是

我删除了将图像显示为纹理的代码，并使用整数来计算接收到的图像数。尽管如此，我每10秒都会收到大约2到4张的图像。也就是说，在Windows窗体应用程序中，我每10秒就会收到大约80到100的图像

在Unity中10秒内接收2图像是无法接受的。我写的代码似乎不是问题，因为它在Windows窗体中工作得很好

bool keepRunning = true;
    private void Decode_MJPEG_Images(string streamTestURL = null)
    {
        keepRunning = true;
        streamTestURL = "http://64.122.208.241:8000/axis-cgi/mjpg/video.cgi?resolution=320x240"; //For Testing purposes only

        // create HTTP request
        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(streamTestURL);
        // get response
        WebResponse resp = req.GetResponse();

        System.IO.Stream imagestream = resp.GetResponseStream();

        const int BufferSize = 5000000;
        byte[] imagebuffer = new byte[BufferSize];
        int a = 2;
        int framecounter = 0;
        int startreading = 0;
        byte[] start_checker = new byte[2];
        byte[] end_checker = new byte[2];

        while (keepRunning)
        {
            start_checker[1] = (byte)imagestream.ReadByte();
            end_checker[1] = start_checker[1];

            //This if statement searches for the JPEG header, and performs the relevant operations
            if (start_checker[0] == 0xff && start_checker[1] == 0xd8)// && Reset ==0)
            {
                Array.Clear(imagebuffer, 0, imagebuffer.Length);
                //Rebuild jpeg header into imagebuffer
                imagebuffer[0] = 0xff;
                imagebuffer[1] = 0xd8;
                a = 2;
                framecounter++;
                startreading = 1;
            }

            //This if statement searches for the JPEG footer, and performs the relevant operations
            if (end_checker[0] == 0xff && end_checker[1] == 0xd9)
            {
                startreading = 0;
                //Write final part of JPEG header into imagebuffer
                imagebuffer[a] = start_checker[1];
                System.IO.MemoryStream jpegstream = new System.IO.MemoryStream(imagebuffer);

                Debug.Log("Received Full Image");
                Debug.Log(framecounter.ToString());


                //Display Image
            }

            //This if statement fills the imagebuffer, if the relevant flags are set
            if (startreading == 1 && a < BufferSize)
            {
                imagebuffer[a] = start_checker[1];
                a++;
            }

            //Catches error condition where a = buffer size - this should not happen in normal operation
            if (a == BufferSize)
            {
                a = 2;
                startreading = 0;
            }

            start_checker[0] = start_checker[1];
            end_checker[0] = end_checker[1];

        }


        resp.Close();
    }

我尝试过的事情：

我认为问题来自Unity3D编辑器运行时，所以我调用了Windows 10 64位并运行了它，但这并没有解决问题

将脚本后端从Mono2x更改为IL2CPP，但问题仍然存在

将Api兼容性级别从.NET 2.0更改为.NET 2.0子集，但没有任何更改

下面是一个有这个问题的简单函数I。它在Unity上运行得太慢，尽管我从另一个线程调用它

bool keepRunning = true;
    private void Decode_MJPEG_Images(string streamTestURL = null)
    {
        keepRunning = true;
        streamTestURL = "http://64.122.208.241:8000/axis-cgi/mjpg/video.cgi?resolution=320x240"; //For Testing purposes only

        // create HTTP request
        HttpWebRequest req = (HttpWebRequest)WebRequest.Create(streamTestURL);
        // get response
        WebResponse resp = req.GetResponse();

        System.IO.Stream imagestream = resp.GetResponseStream();

        const int BufferSize = 5000000;
        byte[] imagebuffer = new byte[BufferSize];
        int a = 2;
        int framecounter = 0;
        int startreading = 0;
        byte[] start_checker = new byte[2];
        byte[] end_checker = new byte[2];

        while (keepRunning)
        {
            start_checker[1] = (byte)imagestream.ReadByte();
            end_checker[1] = start_checker[1];

            //This if statement searches for the JPEG header, and performs the relevant operations
            if (start_checker[0] == 0xff && start_checker[1] == 0xd8)// && Reset ==0)
            {
                Array.Clear(imagebuffer, 0, imagebuffer.Length);
                //Rebuild jpeg header into imagebuffer
                imagebuffer[0] = 0xff;
                imagebuffer[1] = 0xd8;
                a = 2;
                framecounter++;
                startreading = 1;
            }

            //This if statement searches for the JPEG footer, and performs the relevant operations
            if (end_checker[0] == 0xff && end_checker[1] == 0xd9)
            {
                startreading = 0;
                //Write final part of JPEG header into imagebuffer
                imagebuffer[a] = start_checker[1];
                System.IO.MemoryStream jpegstream = new System.IO.MemoryStream(imagebuffer);

                Debug.Log("Received Full Image");
                Debug.Log(framecounter.ToString());


                //Display Image
            }

            //This if statement fills the imagebuffer, if the relevant flags are set
            if (startreading == 1 && a < BufferSize)
            {
                imagebuffer[a] = start_checker[1];
                a++;
            }

            //Catches error condition where a = buffer size - this should not happen in normal operation
            if (a == BufferSize)
            {
                a = 2;
                startreading = 0;
            }

            start_checker[0] = start_checker[1];
            end_checker[0] = end_checker[1];

        }


        resp.Close();
    }

bool-keepRunning=true；
私有void Decode_MJPEG_图像（字符串streamTestURL=null）
{
保持修剪=正确；
streamTestURL=”http://64.122.208.241:8000/axis-cgi/mjpg/video.cgi？分辨率=320x240“；//仅用于测试目的
//创建HTTP请求
HttpWebRequest req=（HttpWebRequest）WebRequest.Create（streamTestURL）；
//得到回应
WebResponse resp=req.GetResponse（）；
System.IO.Stream imagestream=resp.GetResponseStream（）；
const int BufferSize=5000000；
byte[]imagebuffer=新字节[BufferSize]；
INTA=2；
int framecounter=0；
int startreding=0；
字节[]开始检查=新字节[2]；
字节[]结束检查程序=新字节[2]；
同时（继续修剪）
{
启动检查程序[1]=（字节）imagestream.ReadByte（）；
结束检查程序[1]=开始检查程序[1]；
//此if语句搜索JPEG标头，并执行相关操作
如果（启动检查程序[0]==0xff&&start检查程序[1]==0xd8）/&&Reset==0）
{
Array.Clear（imagebuffer，0，imagebuffer.Length）；
//将jpeg头重建到imagebuffer中
imagebuffer[0]=0xff；
imagebuffer[1]=0xd8；
a=2；
帧计数器++；
Startreding=1；
}
//此if语句搜索JPEG页脚，并执行相关操作
if（结束检查程序[0]==0xff&&end检查程序[1]==0xd9）
{
startreding=0；
//将JPEG头的最后一部分写入imagebuffer
imagebuffer[a]=启动检查程序[1]；
System.IO.MemoryStream JPEG流=新的System.IO.MemoryStream（imagebuffer）；
Log（“接收到完整映像”）；
Log（framecounter.ToString（））；
//显示图像
}
//如果设置了相关标志，则此if语句将填充imagebuffer
if（startreding==1&&a

现在我把这个问题归咎于HttpWebRequest。也许它在团结中执行得很差。不确定

---

发生什么事了？为什么会这样？我该如何修复它呢？

是不是必须使用

读取[大量]

而不是

读取

阅读[很多]
：


返回值类型：System.Int32读取到缓冲区的总字节数。如果有那么多字节当前不可用，则该值可以小于请求的字节数

可以想象，
ReadAsync
可能会有所帮助，尽管它会产生截然不同的代码。
对于您所说的代码的哪一部分存在性能问题，我有点困惑——是显示MPG还是您在此处发布的代码片段？假设HttpRequest不是您的问题（您可以在Fiddler中轻松测试以查看调用和获取实际需要多长时间），那么我猜您的问题在于MPG的显示，而不是您发布的代码（WinForms和Unity之间没有什么不同）

我的猜测是，如果问题在Unity中，您是否将创建的MemoryStream传递给Unity以创建图形资源？您的代码看起来像是在读取流