Merge pull request #8 from agusmakmun/mr-7

first commit for image crop on axis. added function #7

Author: agusmakmun

image_optimizer/fields.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.db.models import ImageField
 from .utils import image_optimizer
 
@@ -11,19 +8,26 @@ class OptimizedImageField(ImageField):
     def save_form_data(self, instance, data):
         """Remove the OptimizedNotOptimized object on clearing the image."""
         # Are we updating an image?
-        updating_image = True if data and getattr(instance, self.name) != data else False
+        updating_image = (
+            True if data and getattr(instance, self.name) != data else False
+        )
 
         if updating_image:
             data = image_optimizer(
                 data,
                 self.optimized_image_output_size,
-                self.optimized_image_resize_method
+                self.optimized_image_resize_method,
             )
 
         super().save_form_data(instance, data)
 
-    def __init__(self, optimized_image_output_size=None,
-                 optimized_image_resize_method=None, *args, **kwargs):
+    def __init__(
+        self,
+        optimized_image_output_size=None,
+        optimized_image_resize_method=None,
+        *args,
+        **kwargs
+    ):
         """
         Initialize OptimizedImageField instance.
 
@@ -51,10 +55,10 @@ def deconstruct(self):
         """
         name, path, args, kwargs = super().deconstruct()
 
-        if kwargs.get('optimized_image_output_size'):
-            del kwargs['optimized_image_output_size']
+        if kwargs.get("optimized_image_output_size"):
+            del kwargs["optimized_image_output_size"]
 
-        if kwargs.get('optimized_image_resize_method'):
-            del kwargs['optimized_image_resize_method']
+        if kwargs.get("optimized_image_resize_method"):
+            del kwargs["optimized_image_resize_method"]
 
         return name, path, args, kwargs

image_optimizer/settings.py

@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.conf import settings
 
-OPTIMIZED_IMAGE_METHOD = getattr(settings, 'OPTIMIZED_IMAGE_METHOD', 'pillow')
-TINYPNG_KEY = getattr(settings, 'TINYPNG_KEY', None)
+OPTIMIZED_IMAGE_METHOD = getattr(settings, "OPTIMIZED_IMAGE_METHOD", "pillow")
+TINYPNG_KEY = getattr(settings, "TINYPNG_KEY", None)

image_optimizer/utils.py

@@ -1,15 +1,12 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
-from io import BytesIO
-from PIL import Image
-from resizeimage import resizeimage
-
 import tinify
 import logging
 import requests
+from io import BytesIO
+from PIL import Image
+from resizeimage import resizeimage
+from uuid import uuid4
 
-from .settings import (OPTIMIZED_IMAGE_METHOD, TINYPNG_KEY)
+from .settings import OPTIMIZED_IMAGE_METHOD, TINYPNG_KEY
 
 
 BACKGROUND_TRANSPARENT = (255, 255, 255, 0)
@@ -23,10 +20,10 @@ def get_file_extension(file_name):
     extension = None
 
     # Get image file extension
-    if file_name.split('.')[-1].lower() != 'jpg':
-        extension = file_name.split('.')[-1].upper()
+    if file_name.split(".")[-1].lower() != "jpg":
+        extension = file_name.split(".")[-1].upper()
     else:
-        extension = 'JPEG'
+        extension = "JPEG"
 
     return extension
 
@@ -39,11 +36,11 @@ def image_optimizer(image_data, output_size=None, resize_method=None):
     """
     Optimize an image that has not been saved to a file.
     :param `image_data` is image data, e.g from request.FILES['image']
-    :param `output_size` is float pixel scale of image (width, height) or None, e.g: (400, 300)
-    :param `resize_method` is string resize method, choices are: None, "thumbnail", or "cover".
+    :param `output_size` is float pixel scale of image (width, height) or None, for example: (400, 300) # noqa: E501
+    :param `resize_method` is string resize method, choices are: None, "thumbnail", or "cover". # noqa: E501
     :return optimized image data.
     """
-    if OPTIMIZED_IMAGE_METHOD == 'pillow':
+    if OPTIMIZED_IMAGE_METHOD == "pillow":
         image = Image.open(image_data)
         bytes_io = BytesIO()
 
@@ -53,49 +50,108 @@ def image_optimizer(image_data, output_size=None, resize_method=None):
         # resize_method. 'thumbnail' is used by default
         if output_size is not None:
 
-            if resize_method not in ('thumbnail', 'cover', None):
-                message = 'optimized_image_resize_method misconfigured, it\'s value must be \'thumbnail\', \'cover\' or None'
+            if resize_method not in ("thumbnail", "cover", None):
+                message = (
+                    "optimized_image_resize_method misconfigured, "
+                    "it's value must be 'thumbnail', 'cover' or None"
+                )
                 raise Exception(message)
 
-            elif resize_method is 'thumbnail':
-                image = resizeimage.resize_thumbnail(image, output_size, resample=Image.LANCZOS)
+            elif resize_method == "thumbnail":
+                image = resizeimage.resize_thumbnail(
+                    image, output_size, resample=Image.LANCZOS
+                )
 
-            elif resize_method is 'cover':
+            elif resize_method == "cover":
                 image = resizeimage.resize_cover(image, output_size, validate=False)
 
-            output_image = Image.new('RGBA', output_size, BACKGROUND_TRANSPARENT)
-            output_image_center = (int((output_size[0] - image.size[0]) / 2),
-                                   int((output_size[1] - image.size[1]) / 2))
+            output_image = Image.new(
+                "RGBA",
+                output_size,
+                BACKGROUND_TRANSPARENT,
+            )
+            output_image_center = (
+                int((output_size[0] - image.size[0]) / 2),
+                int((output_size[1] - image.size[1]) / 2),
+            )
 
             output_image.paste(image, output_image_center)
 
         else:
-            # If output_size is None the output_image would be the same as source
+            # If output_size is None the output_image
+            # would be the same as source
             output_image = image
 
         # If the file extension is JPEG, convert the output_image to RGB
-        if extension == 'JPEG':
-            output_image = output_image.convert('RGB')
+        if extension == "JPEG":
+            output_image = output_image.convert("RGB")
 
         output_image.save(bytes_io, format=extension, optimize=True)
 
         image_data.seek(0)
         image_data.file.write(bytes_io.getvalue())
         image_data.file.truncate()
 
-    elif OPTIMIZED_IMAGE_METHOD == 'tinypng':
+    elif OPTIMIZED_IMAGE_METHOD == "tinypng":
         # disable warning info
         requests.packages.urllib3.disable_warnings()
 
         # just info for people
         if any([output_size, resize_method]):
-            message = '[django-image-optimizer] "output_size" and "resize_method" only for OPTIMIZED_IMAGE_METHOD="pillow"'
+            message = (
+                '[django-image-optimizer] "output_size" and "resize_method" '
+                'only for OPTIMIZED_IMAGE_METHOD="pillow"'
+            )
             logging.info(message)
 
         tinify.key = TINYPNG_KEY
-        optimized_buffer = tinify.from_buffer(image_data.file.read()).to_buffer()
+        optimized_buffer = tinify.from_buffer(
+            image_data.file.read()
+        ).to_buffer()  # noqa: E501
         image_data.seek(0)
         image_data.file.write(optimized_buffer)
         image_data.file.truncate()
 
     return image_data
+
+
+def crop_image_on_axis(image, width, height, x, y, extension):
+    """
+    function to crop the image using axis (using Pillow).
+    :param `image` is image data, e.g from request.FILES['image']
+    :param `width` float width of image
+    :param `height` float height of image
+    :param `x` is float x axis
+    :param `y` is float y axis
+    :param `extension` is string, e.g: ".png"
+    """
+    # Open the passed image
+    img = Image.open(image)
+
+    # Initialise bytes io
+    bytes_io = BytesIO()
+
+    # crop the image through axis
+    img = img.crop((x, y, width + x, height + y))
+
+    # resize the image and optimise it for file size,
+    # making smaller as possible
+    img = img.resize((width, height), Image.ANTIALIAS)
+
+    # This line is optional, for safe side, image name should be unique.
+    img.name = "{}.{}".format(uuid4().hex, extension)
+
+    # If the file extension is JPEG, convert the output_image to RGB
+    if extension == "JPEG":
+        img = image.convert("RGB")
+    img.save(bytes_io, format=extension, optimize=True)
+
+    # return the image
+    image.seek(0)
+
+    # Write back new image
+    image.file.write(bytes_io.getvalue())
+
+    # truncate the file size
+    image.file.truncate()
+    return image

image_optimizer_demo/app_demo/admin.py

@@ -1,22 +1,33 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.contrib import admin
 from app_demo.models import (
     Post,
     Collaborator,
+    OtherImage,
 )
+from app_demo.forms import CropImageAxisForm
 
 
 class PostAdmin(admin.ModelAdmin):
-    list_display = ['title', 'created']
-    list_filter = ['created']
+    list_display = ["title", "created"]
+    list_filter = ["created"]
 
 
 class CollaboratorAdmin(admin.ModelAdmin):
-    list_display = ['name', 'created']
-    list_filter = ['created']
+    list_display = ["name", "created"]
+    list_filter = ["created"]
+
+
+class CropImageAxisAdmin(admin.ModelAdmin):
+    list_display = ["created", "image"]
+    list_filter = ["created"]
+    form = CropImageAxisForm
+
+    def get_form(self, request, *args, **kwargs):
+        form = super().get_form(request, *args, **kwargs)
+        form.request = request
+        return form
 
 
 admin.site.register(Post, PostAdmin)
 admin.site.register(Collaborator, CollaboratorAdmin)
+admin.site.register(OtherImage, CropImageAxisAdmin)

image_optimizer_demo/app_demo/apps.py

@@ -1,8 +1,5 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.apps import AppConfig
 
 
 class AppDemoConfig(AppConfig):
-    name = 'app_demo'
+    name = "app_demo"

image_optimizer_demo/app_demo/forms.py

@@ -0,0 +1,38 @@
+from django import forms
+from .models import OtherImage
+from image_optimizer.utils import crop_image_on_axis, get_file_extension
+
+
+class CropImageAxisForm(forms.ModelForm):
+    width = forms.IntegerField()
+    height = forms.IntegerField()
+    x = forms.FloatField()
+    y = forms.FloatField()
+
+    def save(self, commit=True):
+        instance = super().save(commit=False)
+        request = self.request
+
+        # process on create only
+        image = request.FILES.get("image")
+        if image is not None:
+            width = float(request.POST["width"])
+            height = float(request.POST["height"])
+            x = float(request.POST["x"])
+            y = float(request.POST["y"])
+            extension = get_file_extension(image.name)
+
+            try:
+                image = crop_image_on_axis(image, width, height, x, y, extension)
+            except ValueError as error:
+                raise forms.ValidationError(error)
+
+            instance.image = image
+            instance.save(commit=True)
+            return instance
+
+        return super().save(commit)
+
+    class Meta:
+        model = OtherImage
+        fields = ["image"]