Create Thumbnail from IIIF

iiif_prezi3/helpers/add_thumbnail.py

@@ -1,7 +1,8 @@
 from ..loader import monkeypatch_schema
 from ..skeleton import (AccompanyingCanvas, Annotation, AnnotationCollection,
                         AnnotationPage, Canvas, Collection, Manifest,
-                        PlaceholderCanvas, Range, Reference, ResourceItem)
+                        PlaceholderCanvas, Range, Reference, ResourceItem,
+                        ServiceItem, ServiceItem1)
 
 
 class AddThumbnail:
@@ -21,5 +22,75 @@ def add_thumbnail(self, image_url, **kwargs):
         self.thumbnail.append(new_thumbnail)
         return new_thumbnail
 
+    def create_thumbnail_from_iiif(self, url, preferred_width=500, **kwargs):
+        """Adds an image thumbnail to a manifest or canvas based on a IIIF service.
+
+        Args:
+            url (str): An HTTP URL which points at a IIIF Image response.
+            preferred_width (int, optional): the preferred width of the thumbnail.
+            **kwargs (): see ResourceItem.
+
+        Returns:
+            new_thumbnail (ResourceItem): The updated list of thumbnails, including the newly-created one.
+        """
+        image_response = ResourceItem(id=url, type='Image')
+        image_info = image_response.set_hwd_from_iiif(url)
+        context = image_info.get('@context', '')
+
+        if 'sizes' in image_info:
+            best_fit_size = max(
+                (size for size in image_info['sizes'] if size["width"] <= preferred_width),
+                key=lambda size: size["width"],
+                default=image_info['sizes'][0]
+            )
+            thumbnail_id = f"{url.replace('/info.json', '')}/full/{best_fit_size['width']},{best_fit_size['height']}/0/default.jpg"
+        else:
+            thumbnail_id = f"{url.replace('/info.json', '')}/full/full/0/default.jpg" if context == "http://iiif.io/api/image/2/context.json" else f"{url.replace('/info.json', '')}/full/max/0/default.jpg"
+
+        if context == "http://iiif.io/api/image/2/context.json":
+            profile_data = image_info.get('profile', [])
+            if isinstance(profile_data, str):
+                profile = profile_data
+            elif isinstance(profile_data, list):
+                profile = next((item for item in profile_data if isinstance(item, str)), '')
+            else:
+                profile = ''
+            service = ServiceItem1(
+                id=image_info['@id'],
+                profile=profile,
+                type="ImageService2",
+                format="image/jpeg"
+            )
+            if profile == "http://iiif.io/api/image/2/level0.json" and 'sizes' in image_info:
+                thumbnail_id = f"{url.replace('/info.json', '')}/full/{best_fit_size['width']},/0/default.jpg"
+        else:
+            service = ServiceItem(
+                id=image_info['id'],
+                profile=image_info.get('profile', ''),
+                type=image_info.get('type', 'ImageService'),
+                format="image/jpeg"
+            )
+
+        new_thumbnail = ResourceItem(
+            id=thumbnail_id,
+            type='Image',
+            format="image/jpeg",
+            **kwargs
+        )
+        if 'sizes' in image_info:
+            new_thumbnail.height = best_fit_size.get('height')
+            new_thumbnail.width = best_fit_size.get('width')
+        elif 'height' in image_info and 'width' in image_info:
+            new_thumbnail.height = image_info['height']
+            new_thumbnail.width = image_info['width']
+
+        if not hasattr(self, 'thumbnail') or self.thumbnail is None:
+            self.thumbnail = []
+
+        new_thumbnail.add_service(service)
+        self.thumbnail.append(new_thumbnail)
+
+        return self.thumbnail
+
 
 monkeypatch_schema([Canvas, PlaceholderCanvas, AccompanyingCanvas, AnnotationPage, Collection, Manifest, Annotation, Range, ResourceItem, AnnotationCollection, Reference], AddThumbnail)

tests/test_add_thumbnail.py

@@ -0,0 +1,254 @@
+import unittest
+from unittest.mock import Mock, patch
+
+from iiif_prezi3 import Manifest
+
+
+class AddThumbnailTests(unittest.TestCase):
+
+    def setUp(self):
+        self.manifest = Manifest(label={'en': ['Manifest label']})
+
+    @patch('iiif_prezi3.helpers.set_hwd_from_iiif.requests.get')
+    def test_create_thumbnail_from_iiif_v3(self, mockrequest_get):
+        image_id = 'https://fixtures.iiif.io/other/level0/Glen/photos/gottingen'
+        image_info_url = f'{image_id}/info.json'
+
+        # successful response with dimensions
+        mockresponse = Mock(status_code=200)
+        mockrequest_get.return_value = mockresponse
+        # set mock to return minimal image api response
+        mockresponse.json.return_value = {
+            "@context": "http://iiif.io/api/image/3/context.json",
+            "id": "https://fixtures.iiif.io/other/level0/Glen/photos/gottingen",
+            "type": "ImageService3",
+            "protocol": "http://iiif.io/api/image",
+            "profile": "level0",
+            "width": 4032,
+            "height": 3024,
+            "sizes": [
+                {
+                  "width": 126,
+                  "height": 95
+                },
+                {
+                    "width": 252,
+                    "height": 189
+                },
+                {
+                    "width": 504,
+                    "height": 378
+                },
+                {
+                    "width": 1008,
+                    "height": 756
+                },
+                {
+                    "width": 2016,
+                    "height": 1512
+                },
+                {
+                    "width": 4032,
+                    "height": 3024
+                }
+            ]
+        }
+
+        thumbnail = self.manifest.create_thumbnail_from_iiif(image_info_url)[0]
+
+        # check thumbnail matches preferred size
+        self.assertEqual(thumbnail.height, 189)
+        self.assertEqual(thumbnail.width, 252)
+
+        # check thumbnail id
+        self.assertEqual(thumbnail.id, "https://fixtures.iiif.io/other/level0/Glen/photos/gottingen/full/252,189/0/default.jpg")
+
+        # check thumbnail service
+        self.assertEqual(thumbnail.service[0].profile, "level0")
+        self.assertEqual(thumbnail.service[0].type, "ImageService3")
+
+    @patch('iiif_prezi3.helpers.set_hwd_from_iiif.requests.get')
+    def test_create_thumbnail_from_iiif_v2(self, mockrequest_get):
+        image_id = 'https://iiif.io/api/image/2.1/example/reference/918ecd18c2592080851777620de9bcb5-gottingen'
+        image_info_url = f'{image_id}/info.json'
+
+        # successful response with dimensions
+        mockresponse = Mock(status_code=200)
+        mockrequest_get.return_value = mockresponse
+        # set mock to return minimal image api response
+        mockresponse.json.return_value = {
+            "@context": "http://iiif.io/api/image/2/context.json",
+            "@id": "https://iiif.io/api/image/2.1/example/reference/918ecd18c2592080851777620de9bcb5-gottingen",
+            "height": 3024,
+            "profile": [
+                "http://iiif.io/api/image/2/level1.json",
+                {
+                    "formats": [
+                        "jpg",
+                        "png"
+                    ],
+                    "qualities": [
+                        "default",
+                        "color",
+                        "gray"
+                    ]
+                }
+            ],
+            "protocol": "http://iiif.io/api/image",
+            "tiles": [
+                {
+                    "height": 512,
+                    "scaleFactors": [
+                        1,
+                        2,
+                        4
+                    ],
+                    "width": 512
+                }
+            ],
+            "width": 4032
+        }
+
+        thumbnail = self.manifest.create_thumbnail_from_iiif(image_info_url)[0]
+
+        # check thumbnail matches preferred size
+        self.assertEqual(thumbnail.height, 3024)
+        self.assertEqual(thumbnail.width, 4032)
+
+        # Since info_json has no sizes, use full/full
+        self.assertEqual(thumbnail.id, "https://iiif.io/api/image/2.1/example/reference/918ecd18c2592080851777620de9bcb5-gottingen/full/full/0/default.jpg")
+
+        # check thumbnail service
+        self.assertEqual(thumbnail.service[0].profile, "http://iiif.io/api/image/2/level1.json")
+        self.assertEqual(thumbnail.service[0].type, "ImageService2")
+
+    @patch('iiif_prezi3.helpers.set_hwd_from_iiif.requests.get')
+    def test_create_thumbnail_from_level_0_iiif_v3(self, mockrequest_get):
+        image_id = 'https://iiif-test.github.io/test2/images/IMG_5949'
+        image_info_url = f'{image_id}/info.json'
+        mockresponse = Mock(status_code=200)
+        mockrequest_get.return_value = mockresponse
+        mockresponse.json.return_value = {
+          "tiles": [
+            {
+              "scaleFactors": [
+                32,
+                16,
+                8,
+                4,
+                2,
+                1
+              ],
+              "width": 1024,
+              "height": 1024
+            }
+          ],
+          "protocol": "http://iiif.io/api/image",
+          "sizes": [
+            {
+              "width": 126,
+              "height": 95
+            },
+            {
+              "width": 252,
+              "height": 189
+            },
+            {
+              "width": 504,
+              "height": 378
+            },
+            {
+              "width": 1008,
+              "height": 756
+            },
+            {
+              "width": 2016,
+              "height": 1512
+            },
+            {
+              "width": 4032,
+              "height": 3024
+            }
+          ],
+          "profile": "level0",
+          "width": 4032,
+          "id": "https://iiif-test.github.io/test2/images/IMG_5949",
+          "type": "ImageService3",
+          "@context": "http://iiif.io/api/image/3/context.json",
+          "height": 3024
+        }
+
+        thumbnail = self.manifest.create_thumbnail_from_iiif(image_info_url)[0]
+        self.assertEqual(thumbnail.height, 189)
+        self.assertEqual(thumbnail.width, 252)
+        self.assertEqual(
+            thumbnail.id,
+    "https://iiif-test.github.io/test2/images/IMG_5949/full/252,189/0/default.jpg"
+        )
+
+        # check thumbnail service
+        self.assertEqual(thumbnail.service[0].profile, "level0")
+        self.assertEqual(thumbnail.service[0].type, "ImageService3")
+
+    @patch('iiif_prezi3.helpers.set_hwd_from_iiif.requests.get')
+    def test_create_thumbnail_from_level_0_iiif_v2(self, mockrequest_get):
+        image_id = 'https://iiif-test.github.io/test2/images/IMG_8669'
+        image_info_url = f'{image_id}/info.json'
+        mockresponse = Mock(status_code=200)
+        mockrequest_get.return_value = mockresponse
+        mockresponse.json.return_value = {
+          "tiles": [
+            {
+              "scaleFactors": [
+                32,
+                16,
+                8,
+                4,
+                2,
+                1
+              ],
+              "width": 1024,
+              "height": 1024
+            }
+          ],
+          "protocol": "http://iiif.io/api/image",
+          "sizes": [
+            {
+              "width": 126,
+              "height": 95
+            },
+            {
+              "width": 252,
+              "height": 189
+            },
+            {
+              "width": 504,
+              "height": 378
+            },
+            {
+              "width": 1008,
+              "height": 756
+            },
+            {
+              "width": 2016,
+              "height": 1512
+            },
+            {
+              "width": 4032,
+              "height": 3024
+            }
+          ],
+          "profile": "http://iiif.io/api/image/2/level0.json",
+          "width": 4032,
+          "@id": "https://iiif-test.github.io/test2/images/IMG_8669",
+          "@context": "http://iiif.io/api/image/2/context.json",
+          "height": 3024
+        }
+
+        thumbnail = self.manifest.create_thumbnail_from_iiif(image_info_url)[0]
+        self.assertEqual(thumbnail.height, 189)
+        self.assertEqual(thumbnail.width, 252)
+        self.assertEqual(
+            thumbnail.id,
+            "https://iiif-test.github.io/test2/images/IMG_8669/full/252,/0/default.jpg"
+        )