Question

我正在为这些摄像头开发网络摄像头查看器：http://www.canvision.net/support/pt300-cgi/GetData.htm 数据到达如下：

HTTP/1.0 200 OK
Date: Wed, 19 Feb 2003 03:40:16 GMT
Server: WYM/1.0
Connection: close
Content-Type: multipart/x-mixed-replace;boundary=WINBONDBOUDARY
Last-Modified: Wed, 19 Feb 2003 03:40:16 GMT
Pragma: no-cache
Cache-Control: no-cache
Expires: 01 Jan 1970 00:00:00 GMT
--WINBONDBOUDARY
Content-Type: image/jpeg

--WINBONDBOUDARY
Content-Type: image/jpeg

这些是我的NSURLConnection委托方法：

- (void)connection:(NSURLConnection *)theConnection didReceiveData:(NSData *)data
{
     [currentData appendData:data];
}


(void)connection:(NSURLConnection *)theConnection didReceiveResponse:(NSURLResponse *)response{
 NSLog(@"response with mime: %@ length:%i",[response MIMEType],[currentData length]);
 if([[response MIMEType] isEqualToString:@"image/jpeg"] && [currentData length] != 0){
      currentFrame = [UIImage imageWithData:currentData];
      NSLog(@"valid frame");
      [image setImage:currentFrame];
      frameCounter++;
 }
 else {
      NSLog(@"other data:%@",currentData);
 }
 currentFrame = nil;
 if (currentData == receivedData1)//swap buffers
    currentData = receivedData2;

else
    currentData = receivedData1;

 [currentData setLength:0];
 [currentFrame release];
}

这一切都很好，控制台输出看起来像你期望的那样：

[Session started at 2011-02-21 20:20:39 +0100.]
2011-02-21 20:20:43.237 MotionJPEG[16330:207] response with mime: multipart/x-mixed-replace length:0
2011-02-21 20:20:43.261 MotionJPEG[16330:207] other data:<>
2011-02-21 20:20:43.262 MotionJPEG[16330:207] response with mime: image/jpeg length:0
2011-02-21 20:20:43.263 MotionJPEG[16330:207] other data:<>
2011-02-21 20:20:43.340 MotionJPEG[16330:207] response with mime: image/jpeg length:4608
2011-02-21 20:20:43.340 MotionJPEG[16330:207] valid frame
2011-02-21 20:20:43.445 MotionJPEG[16330:207] response with mime: image/jpeg length:4600
2011-02-21 20:20:43.446 MotionJPEG[16330:207] valid frame
2011-02-21 20:20:43.544 MotionJPEG[16330:207] response with mime: image/jpeg length:4580
2011-02-21 20:20:43.545 MotionJPEG[16330:207] valid frame

然而，Cam支持另一种模式，其中在jpeg之间嵌入了额外的信息：

HTTP/1.0 200 OK
Date: Wed, 19 Feb 2003 03:40:16 GMT
Server: WYM/1.0
Connection: close
Content-Type: multipart/x-mixed-replace;boundary=WINBONDBOUDARY
Last-Modified: Wed, 19 Feb 2003 03:40:16 GMT
Pragma: no-cache
Cache-Control: no-cache
Expires: 01 Jan 1970 00:00:00 GMT
--WINBONDBOUDARY
Content-Type: image/jpeg

--WINBONDBOUDARY
Content-Type: text/plain

--WINBONDBOUDARY
Content-Type: image/jpeg

--WINBONDBOUDARY
Content-Type: text/plain

在这种模式下，我希望代码正常工作，并且

将文本/普通部分写入控制台

NSLog(@"other data:%@",currentData);

线。但是，出于某种原因，输出看起来完全一样，并且它永远不会用mime：text / plain表示响应相反，明文部分附加到jpeg，UIImageView无法显示数据。为什么NSURLConnection无法识别文本/普通部分？以下是完整的来源：http://renehopf.de/MotionJPEG.zip 但为了重现这个问题，你需要相同的网络摄像头......

谢谢，

雷

NSURLConnection didReceiveResponse无法识别多种MIME类型

0 个答案: