可能重复:
如何使用请求下载图像
我知道获取URL非常简单requests.get,我可以获取原始响应体并将其保存到文件中,但是对于大文件,有没有办法直接流式传输到文件？就像我正在下载带有它的电影一样？
我正在关注http://developer.apple.com/iphone/library/qa/qa2010/qa1702.html上的参考资料,以从iPhone摄像头捕获视频.除了该页面的代码之外,这是一个新项目.我也将AVFoundation框架添加到项目中.这是我得到的链接器错误:
Build my project of project my project with configuration Debug
CompileC "build/my project.build/Debug-iphoneos/my project.build/Objects-normal/armv6/MainViewController.o" /Users/mwilliamson/Projects/my_project/iphone/Classes/MainViewController.m normal armv6 objective-c com.apple.compilers.gcc.4_2
cd /Users/mwilliamson/Projects/my_project/iphone
setenv LANG en_US.US-ASCII
setenv PATH "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/opt/local/bin:/usr/local/git/bin"
/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.2 -x objective-c -arch armv6 -fmessage-length=0 -pipe -std=c99 -Wno-trigraphs -fpascal-strings -O0 -Wreturn-type -Wunused-variable -isysroot /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS4.0.sdk -fvisibility=hidden -gdwarf-2 -mthumb -miphoneos-version-min=4.0 -iquote "/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/my project-generated-files.hmap" "-I/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/my project-own-target-headers.hmap" "-I/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/my project-all-target-headers.hmap" -iquote "/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/my project-project-headers.hmap" -F/Users/mwilliamson/Projects/my_project/iphone/build/Debug-iphoneos -I/Users/mwilliamson/Projects/my_project/iphone/build/Debug-iphoneos/include -I/Users/mwilliamson/Projects/my_project/iphone/opencv_device/include "-I/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/DerivedSources/armv6" "-I/Users/mwilliamson/Projects/my_project/iphone/build/my project.build/Debug-iphoneos/my project.build/DerivedSources" -include /var/folders/kW/kW6u6B7SGyGYu+nNumtIa++++TI/-Caches-/com.apple.Xcode.501/SharedPrecompiledHeaders/my_project_Prefix-alujyqxskcuyuogdsynmjyrkxbhh/my_project_Prefix.pch -c /Users/mwilliamson/Projects/my_project/iphone/Classes/MainViewController.m …我可以使用Python中的OpenCV从我的网络摄像头获取帧.camshift示例接近我想要的,但我不希望人为干预来定义对象.我想获得在几帧的过程中改变的总像素的中心点,即移动物体的中心.
我正在查看pybrain获取服务器监视器警报并确定问题的根本原因.我很高兴使用有监督的学习和策划训练数据集来训练它.数据结构如下:
* Server Type **A** #1
* Alarm type 1
* Alarm type 2
* Server Type **A** #2
* Alarm type 1
* Alarm type 2
* Server Type **B** #1
* Alarm type **99**
* Alarm type 2
所以有n个服务器,x警报可以是UP或DOWN.这两个n和x是可变的.
如果服务器A1具有报警1和2的DOWN,那么我们可以说,服务是关闭该服务器上,是导致问题的原因.
如果所有服务器上的警报1都关闭,那么我们可以说服务a是原因.
原因可能有多种选择,因此直接分类似乎不合适.
我还想将以后的数据来源与网络联系起来.比如ping一些外部服务的脚本.
由于串行服务检查,可能不会立即触发所有相应的警报,因此它可以从一台服务器启动,然后在另一台服务器启动后5分钟启动.
我一开始想尝试一些基本的东西:
from pybrain.tools.shortcuts import buildNetwork
from pybrain.datasets import SupervisedDataSet
from pybrain.supervised.trainers import …我正在编写一个关于twisted的REST Web服务,我想使用OAuth 2.0进行授权.是否有一个教程可以帮助我编写OAuth服务器而无需阅读整个规范？我知道它正在草案中,但即使Facebook正在使用它.
我已经让OpenCV使用Python,我甚至可以通过我的网络摄像头检测到一张脸.我真正想要做的是看动作并在动作的中间找到点.camshift样本接近我想要的,但我不想选择要跟踪的视频部分.能够预测下一帧的奖励积分.
这是我目前的代码:
#!/usr/bin/env python
import cv
def is_rect_nonzero(r):
(_,_,w,h) = r
return (w > 0) and (h > 0)
class CamShiftDemo:
def __init__(self):
self.capture = cv.CaptureFromCAM(0)
cv.NamedWindow( "CamShiftDemo", 1 )
self.storage = cv.CreateMemStorage(0)
self.cascade = cv.Load("/usr/local/share/opencv/haarcascades/haarcascade_mcs_upperbody.xml")
self.last_rect = ((0, 0), (0, 0))
def run(self):
hist = cv.CreateHist([180], cv.CV_HIST_ARRAY, [(0,180)], 1 )
backproject_mode = False
i = 0
while True:
i = (i + 1) % 12
frame = cv.QueryFrame( self.capture )
if i == 0:
found = cv.HaarDetectObjects(frame, self.cascade, self.storage, …我有一段代码,用于设置摄像头的捕获会话以使用OpenCV处理帧,然后使用生成的UIImage从帧中设置UIImageView的image属性.当应用程序启动时,图像视图的图像为零,并且在我按下堆栈上的另一个视图控制器然后将其弹出之前不显示任何帧.然后图像保持不变,直到我再次这样做.NSLog语句显示以大约正确的帧速率调用回调.任何想法为什么它不显示？我将帧速率一直降低到每秒2帧.它的处理速度不够快吗？
这是代码:
- (void)setupCaptureSession {
NSError *error = nil;
// Create the session
AVCaptureSession *session = [[AVCaptureSession alloc] init];
// Configure the session to produce lower resolution video frames, if your
// processing algorithm can cope. We'll specify medium quality for the
// chosen device.
session.sessionPreset = AVCaptureSessionPresetLow;
// Find a suitable AVCaptureDevice
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
// Create a device input with the device and add it to the session.
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device
error:&error];
if (!input) …在Xcode中,我声明了一个前向类,以避免循环导入,例如
@class MyClass;
然后我对该类进行方法调用,例如
[MyClass myMethod];
但我得到了一个前瞻性的警告,例如
警告:接收者'MyClass'是一个前向类,相应的@interface可能不存在
如何在整个项目中隐藏这些内容？
在任何其他Linux发行版上,我可以使用shebang创建一个文件并运行shell脚本,如下所示:
$ chmod +x test.sh
$ ./test.sh Johnny
hello Johnny
但是在谷歌云平台容器优化操作系统上,我得到了 -bash: ./test.sh: Permission denied
如果我加前缀,sh例如sh test.sh Johnny它将起作用.我怎样才能让它正常工作？
$ cat test.sh
#!/usr/bin/env sh
echo "Hello $@"
matt@rancher-4mmm /tmp/matt $ chmod +x test.sh
matt@rancher-4mmm /tmp/matt $ sh ./test.sh matt
Hello matt
matt@rancher-4mmm /tmp/matt $ ./test.sh matt
-bash: ./test.sh: Permission denied
matt@rancher-4mmm /tmp/matt $ ls -la
total 4
drwxr-xr-x 2 matt matt 60 Feb 28 20:00 .
drwxrwxrwt 14 root root 280 Feb 28 19:59 ..
-rwxr-xr-x 1 …我只是为django设置了lightc的fastcgi,但是当它处理url时我得到了fcgi文件路径,例如http://myserver.myhost.com/myproject.fcgi上的 404错误.它需要路由到/而不是/myproject.fcgi.
Lighty conf:
$HTTP["host"] =~ "myproject\.myhost\.com" {
fastcgi.server = (
".fcgi" => (
"localhost" => (
"bin-path" => "/var/www/myproject/myproject.fcgi",
"socket" => "/tmp/myproject.sock",
"check-local" => "disable",
"min-procs" => 2,
"max-procs" => 4,
)
),
)
alias.url = (
"/media" => "/usr/local/lib/python1.6/dist-packages/Django-1.2.1-py2.6.egg/django/contrib/admin/media/",
)
url.rewrite-once = (
"^(/media.*)$" => "$1",
"^/favicon\.ico$" => "/media/favicon.ico",
"^(/.*)$" => "/myproject.fcgi$1",
)
}
myproject.fcgi:
#!/usr/bin/python2.6
import sys, os
# Add a custom Python path.
sys.path.insert(0, "..")
# Switch to the directory of your project. (Optional.)
os.chdir("/var/www/myproject") …我希望我的应用程序在进入时自动拒绝来电.这可以通过iPhone SDK实现吗？