django-exiffield 2.0.0

django-exiffield extracts exif information by utilizing exiftool.

django-exiffield extracts exif information by utilizing exiftool.

Requirements

• exiftool

• Python 3.6

• Django >= 1.8

Installation

1. Install django-exiffield

   pip install django-exiffield

2. Make sure exiftool is executable from you environment.

Integration

Let’s assume we have an image Model with a single ImageField. To extract exif information for an attached image, add an ExifField, specify the name of the ImageField in the source argument

from django.db import models

from exiffield.fields import ExifField


class Image(models.Model):
    image = models.ImageField()
    exif = ExifField(
        source='image',
    )

and create a migration for the new field. That’s it.

After attaching an image to your ImageField, the exif information is stored as a dict on the ExifField. Each exif information of the dictionary consists of two keys:

• desc: A human readable description

• val: The value for the entry.

In the following example we access the camera model

image = Image.objects.get(...)
print(image.exif['Model'])
# {
#     'desc': 'Camera Model Name',
#     'val': 'DMC-GX7',
# }

As the exif information is encoded in a simple dict you can iterate and access the values with all familiar dictionary methods.

Denormalizing Fields

Since the ExifField stores its data simply as text, it is not possible to filter or access indiviual values efficiently. The ExifField provides a convinient way to denormalize certain values using the denormalized_fields argument. It takes a dictionary with the target field as key and a simple getter function of type Callable[[Dict[Dict[str, str]]], Any]. To denormalize a simple value you can use the provided exiffield.getters.exifgetter

from django.db import models

from exiffield.fields import ExifField
from exiffield.getters import exifgetter


class Image(models.Model):
    image = models.ImageField()
    camera = models.CharField(
        editable=False,
        max_length=100,
    )
    exif = ExifField(
        source='image',
        denormalized_fields={
            'camera': exifgetter('Model'),
        },
    )

There are more predefined getters in exiffield.getters:

exifgetter(exif_key: str) -> str

Get an unmodified exif value.

get_type() -> str

Get file type, e.g. video or image

get_datetake -> Optional[datetime]

Get when the file was created as datetime

get_orientation -> exiffield.getters.Orientation

Get orientation of media file. Possible values are LANDSCAPE and PORTRAIT.

get_sequenctype -> exiffield.getters.Mode

Guess if the image was taken in a sequence. Possible values are BURST, BRACKETING, TIMELAPSE and SINGLE.

get_sequencenumber -> int

Get image position in a sequence.

Development

This project is using poetry to manage all dev dependencies. Clone this repository and run

poetry develop

to create a virtual enviroment with all dependencies. You can now run the test suite using

poetry run pytest

This repository follows the angular commit conventions. You can register a pre-commit hook to validate your commit messages by using husky. The configurations are already in place if you have nodejs installed. Just run

npm install

and the pre-commit hook will be registered.