使用python动态将matplotlib图像提供给网络 [英] Dynamically serving a matplotlib image to the web using python
问题描述
已经以类似的方式在此处提出了这个问题，但答案是在我的头上(我是python和Web开发的超级新手)，所以我希望有一种更简单的方法，或者可以用不同的方式解释它.
This question has been asked in a similar way here but the answer was way over my head (I'm super new to python and web development) so I'm hoping there's a simpler way or it could be explained differently.
我正在尝试使用matplotlib生成图像并将其提供服务，而无需先将文件写入服务器.我的代码可能有点愚蠢，但它是这样的:
I'm trying to generate an image using matplotlib and serve it without first writing a file to the server. My code is probably kind of silly, but it goes like this:
import cgi
import matplotlib.pyplot as pyplot
import cStringIO #I think I will need this but not sure how to use
...a bunch of matplotlib stuff happens....
pyplot.savefig('test.png')
print "Content-type: text/html\n"
print """<html><body>
...a bunch of text and html here...
<img src="test.png"></img>
...more text and html...
</body></html>
"""
我认为我应该创建一个cstringIO对象，然后执行以下操作，而不是执行pyplot.savefig('test.png'):
I think that instead of doing pyplot.savefig('test.png'), I am supposed to create a cstringIO object and then do something like this:
mybuffer=cStringIO.StringIO()
pyplot.savefig(mybuffer, format="png")
但是我从那里迷路了.我看过的所有示例(例如 http://lost-theory.org/python/dynamicimg. html )涉及到类似
But I am pretty lost from there. All the examples I've seen (e.g. http://lost-theory.org/python/dynamicimg.html) involve doing something like
print "Content-type: image/png\n"
，我不知道如何将其与我已经输出的HTML集成在一起.
and I don't get how to integrate that with the HTML I'm already outputting.
推荐答案
您应该
- 首先写入cStringIO对象
- 然后编写HTTP标头
- 然后将cStringIO的内容写入stdout
因此，如果在savefig中发生错误，您仍然可以返回其他内容，甚至是另一个标头.某些错误不会更早地识别出来，例如，文本问题，图像尺寸过大等.
Thus, if an error in savefig occured, you could still return something else, even another header. Some errors won't be recognized earlier, e.g., some problems with texts, too large image dimensions etc.
您需要告诉savefig将输出写入何处.您可以这样做:
You need to tell savefig where to write the output. You can do:
format = "png"
sio = cStringIO.StringIO()
pyplot.savefig(sio, format=format)
print "Content-Type: image/%s\n" % format
msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY) # Needed this on windows, IIS
sys.stdout.write(sio.getvalue())
如果要将图像嵌入到HTML中:
If you want to embed the image into HTML:
print "Content-Type: text/html\n"
print """<html><body>
...a bunch of text and html here...
<img src="data:image/png;base64,%s"/>
...more text and html...
</body></html>""" % sio.getvalue().encode("base64").strip()
这篇关于使用python动态将matplotlib图像提供给网络的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
