image handling(donwloading/display) in django using html and form

Sat Feb 4 12:21:53 EST 2017

i want to do some image processing using Django and now work and on the image handling(donwloading/display) using Django. first on my task i dont want to store that images on my server. but i have some problems.
that my code :
urls.py
from django.conf.urls import url
from . import views

urlpatterns = [
#url(r'^$',views.index, name='index'),
url(r'^$',views.calc, name='calc'),
]
file.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form method="POST" enctype="multipart/form-data">
    {% csrf_token %}
    {{ form.as_p }}

    <input type="button" value="Submit">
</form>
{{ flow_direction_uri.url }}
</body>
</html>
forms.py
from django import forms

class ImageUploadForm(forms.Form):
    """Image upload form."""
    image = forms.ImageField()
views.py
from django.shortcuts import render
from django.shortcuts import render_to_response
from django.template import RequestContext
from pygeoprocessing import routing
from django import forms
from blog.forms import ImageUploadForm

def calc(request):
    form = ImageUploadForm()
    if request.method == "POST" and form.is_valid():
        image_file = request.FILES['image']
        form.save()
        '''do something image process'''
        '''and finaly i take that output in standalone python script out of django'''
        outpu1 = "outpu1.tif"
        outpu2 = "outpu2.tif"
        outpu3 = "outpu3.tif"
        outpu4 = "outpu4.tif"

return render_to_response ('blog/calc.html', {'form':form,'output1':output1}, RequestContext(request))
and i take that error :
UnboundLocalError at /
local variable 'output1' referenced before assignment
but i thing so its not that error why if i change to response request to {return render_to_response ('blog/calc.html', {'form':form}, RequestContext(request))
` dont show me that error i can see in the browser two buttons where i can choose image from my files and submit button but i thing so that do nothing.
maybe to use html forms and no Django forms ?