first version of the ImageMetadata

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "scinumtools"
-version = "2.18.2"
+version = "2.18.3"
 authors = [
   { name="Ondrej Pego Jaura", email="vrtulka23@pm.me" },
 ]

requirements.txt

@@ -9,4 +9,5 @@ reportlab
 beautifulsoup4
 toml
 pyyaml
-pygments==2.16.1
+pygments==2.16.1
+piexif

src/scinumtools/__init__.py

@@ -7,6 +7,7 @@
 from scinumtools.row_collector import RowCollector
 from scinumtools.parameter_table import ParameterTable
 from scinumtools.progress_bar import ProgressBar
+from scinumtools.image_metadata import ImageMetadata, Metadata
 
 import scinumtools.units as units
 import scinumtools.solver as solver

src/scinumtools/image_metadata.py

@@ -0,0 +1,63 @@
+from PIL import Image, ExifTags
+import piexif
+import json
+from enum import Enum
+
+class Metadata(Enum):
+    DIR_SETUP    = 'DirSetup'
+    DIR_DATA     = 'DirData'
+    GIT_COMMIT   = 'GitCommit'
+    GIT_BRANCH   = 'GitBranch'
+    DATETIME     = 'DateTime'
+    SETTINGS     = 'Settings'
+
+class ImageMetadata:
+
+    modified:bool = False
+    file_name:str
+    metadata:dict
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, exc_traceback):
+        if self.modified:
+            self.save()
+
+    def __init__(self, file_name:str):
+        self.file_name = file_name
+        with Image.open(file_name) as img:
+            self.metadata = {}
+            if 'exif' in img.info:
+                metadata = piexif.load(img.info['exif'])
+                if piexif.ExifIFD.UserComment in metadata['Exif']:
+                    comments = metadata['Exif'][piexif.ExifIFD.UserComment].decode()
+                    self.metadata = json.loads(comments)
+
+    def __setitem__(self, key:str, value:str):
+        self.set(key,value)
+
+    def __getitem__(self, key:str):
+        return self.get(key)
+
+    def set(self, key:Metadata, value:str):
+        self.metadata[key.value] = value
+        self.modified = True
+
+    def get(self, key:Metadata):
+        return self.metadata[key.value]
+
+    def save(self):
+        img = Image.open(self.file_name)
+        if 'exif' in img.info:
+            metadata = piexif.load(img.info['exif'])
+        else:
+            metadata = {
+                "0th": {}, 
+                "Exif": {}, 
+                "1st": {},
+                "thumbnail": None, 
+                "GPS": {}
+            }
+        metadata['Exif'][piexif.ExifIFD.UserComment] = json.dumps(self.metadata).encode()
+        img.save(self.file_name, img.format, exif=piexif.dump(metadata))

tests/test_image_metadata.py

@@ -0,0 +1,30 @@
+import numpy as np
+import os
+import pytest
+from PIL import Image
+import piexif
+import sys
+sys.path.insert(0, 'src')
+
+from scinumtools import ImageMetadata, Metadata
+
+@pytest.fixture()
+def temp_file():
+    dir_temp = "tmp"
+    name_temp = "thumbnail.png"
+    file_name = f"{dir_temp}/{name_temp}"
+    if not os.path.isdir(dir_temp):
+        os.mkdir(dir_temp)
+    data = np.full((10,10),1)
+    with Image.fromarray(data.astype('uint8')) as im:
+        im.save(file_name)
+    return file_name
+
+def test_read_exif(temp_file):
+    assert os.path.isfile(temp_file)
+
+    with ImageMetadata(temp_file) as im:
+        im.set(Metadata.DATETIME,'World')
+
+    with ImageMetadata(temp_file) as im:
+        assert im.get(Metadata.DATETIME) == 'World'