小编Ara*_*ion的帖子

我一直在尝试在 ASP.NET 中设置 MJPEG 流。我想从 URL 检索 MJEPG 流，并将我获得的每一帧发送到每个连接的客户端。我能够找到的示例只能从设置文件中读取，而不是从 URL 继续流，并通过MultiStreamContent发送整个文件。由于我逐帧检索，因此无法执行此操作。我想知道是否可以用 ASP.NET MVC 做我想做的事。我目前正在使用 AForge 视频从链接中检索 MJPEG 流。我的控制器类代码：

using System.Net.Http;
using System.Web.Http;
using AForge.Video;

namespace VideoPrototypeMVC.Controllers
{
    public class CameraController : ApiController
    {
        int framecounter = 0;
        MJPEGStream stream = new MJPEGStream();

        [HttpGet]
        public void GetVideoContent()
        {   
            stream.Source = @"http://127.0.0.1:5002/stream";
            stream.NewFrame += new NewFrameEventHandler(showFrame);
            stream.Start();
            MultipartContent content = new MultipartContent();
            while (stream.IsRunning)
            {
            //Continues streaming should be here?
            }
        }

        //Can be used to display of a frame …

我正在使用Flask和flask-restful生成一个MJPEG流.出于原因,我想在另一个Python程序中捕获此流,我使用OpenCV(3).问题是请求的第一帧进展顺利.另一方面,未正确接收请求的第二帧(延迟之后),并抛出错误:

[mpjpeg @ 0000017a86f524a0] Expected boundary '--' not found, instead found a line of 82 bytes

多次.

我相信这是因为框架的边界是手动设置的.我将把违规代码放在下面.

MJPEG流生成:

## Controller for the streaming of content.
class StreamContent(Resource):
    @classmethod
    def setVis(self, vis):
        self.savedVis = vis

    def get(self):
        return Response(gen(VideoCamera(self.savedVis)),
                        mimetype='multipart/x-mixed-replace; boundary=frame')


## Generate a new VideoCamera and stream the retrieved frames.    
def gen(camera):
    frame = camera.getFrame()
    while frame != None:
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')
        time.sleep(0.07)
        frame = camera.getFrame()

## Allows for the reading of video frames. …

所以我遇到了一些问题.我从外部API检索一些weatherdata.这将作为JSON返回并发送到Azure IoT中心.流分析将json处理成适当的格式,但我在这里遇到了问题.

元素:Current_Condition是一种数组格式.它总是在[0]位置有一个元素.我只需要从第一个位置获取该数组的数据,而不需要像id那样的过滤器.

这里是完整的数据

{
  "deviceId": "aNewDevice",
  "data": {
    "data": {
      "current_condition": [
        {
          "cloudcover": "0",
          "FeelsLikeC": "0",
          "FeelsLikeF": "32",
          "humidity": "100",
          "observation_time": "10:00 AM",
          "precipMM": "0.0",
          "pressure": "1020",
          "temp_C": "2",
          "temp_F": "36",
          "visibility": "0",
          "weatherCode": "143",
          "weatherDesc": [ { "value": "Fog, Mist" } ],
          "weatherIconUrl": [ { "value": "http://cdn.worldweatheronline.net/images/wsymbols01_png_64/wsymbol_0006_mist.png" } ],
          "winddir16Point": "SSW",
          "winddirDegree": "210",
          "windspeedKmph": "7",
          "windspeedMiles": "4"
        }
      ],
      "request": [
        {
          "query": "Nijmegen, Netherlands",
          "type": "City"
        }
      ]
    }
  }
}

还有一些关于我究竟需要做什么的解释(不只是一个例子或代码答案)将来会很好.(请求元素毕竟有同样的问题.)

提前致谢 :)