Merge pull request #1127 from paperless-ngx/feature-webp-thumbnails

Feature: Change document thumbnails to WebP

.github/workflows/reusable-ci-backend.yml

@@ -74,7 +74,7 @@ jobs:
         name: Install system dependencies
         run: |
           sudo apt-get update -qq
-          sudo apt-get install -qq --no-install-recommends unpaper tesseract-ocr imagemagick ghostscript optipng libzbar0 poppler-utils
+          sudo apt-get install -qq --no-install-recommends unpaper tesseract-ocr imagemagick ghostscript libzbar0 poppler-utils
       -
         name: Install Python dependencies
         run: |

Dockerfile

@@ -77,15 +77,12 @@ ARG RUNTIME_PACKAGES="\
   libraqm0 \
   libgnutls30 \
   libjpeg62-turbo \
-  optipng \
   python3 \
   python3-pip \
   python3-setuptools \
   postgresql-client \
   # For Numpy
   libatlas3-base \
-  # thumbnail size reduction
-  pngquant \
   # OCRmyPDF dependencies
   tesseract-ocr \
   tesseract-ocr-eng \

docker/install_management_commands.sh

@@ -2,7 +2,18 @@
 
 set -eu
 
-for command in document_archiver document_exporter document_importer mail_fetcher document_create_classifier document_index document_renamer document_retagger document_thumbnails document_sanity_checker manage_superuser;
+for command in decrypt_documents \
+	document_archiver \
+	document_exporter \
+	document_importer \
+	mail_fetcher \
+	document_create_classifier \
+	document_index \
+	document_renamer \
+	document_retagger \
+	document_thumbnails \
+	document_sanity_checker \
+	manage_superuser;
 do
 	echo "installing $command..."
 	sed "s/management_command/$command/g" management_script.sh > /usr/local/bin/$command

docs/configuration.rst

@@ -712,13 +712,6 @@ PAPERLESS_CONVERT_TMPDIR=<path>
 
     Default is none, which disables the temporary directory.
 
-PAPERLESS_OPTIMIZE_THUMBNAILS=<bool>
-    Use optipng to optimize thumbnails. This usually reduces the size of
-    thumbnails by about 20%, but uses considerable compute time during
-    consumption.
-
-    Defaults to true.
-
 PAPERLESS_POST_CONSUME_SCRIPT=<filename>
     After a document is consumed, Paperless can trigger an arbitrary script if
     you like.  This script will be passed a number of arguments for you to work
@@ -789,9 +782,6 @@ PAPERLESS_CONVERT_BINARY=<path>
 PAPERLESS_GS_BINARY=<path>
     Defaults to "/usr/bin/gs".
 
-PAPERLESS_OPTIPNG_BINARY=<path>
-    Defaults to "/usr/bin/optipng".
-
 
 .. _configuration-docker:
 

docs/setup.rst

@@ -286,7 +286,6 @@ writing. Windows is not and will never be supported.
 
     *   ``fonts-liberation`` for generating thumbnails for plain text files
     *   ``imagemagick`` >= 6 for PDF conversion
-    *   ``optipng`` for optimizing thumbnails
     *   ``gnupg`` for handling encrypted documents
     *   ``libpq-dev`` for PostgreSQL
     *   ``libmagic-dev`` for mime type detection
@@ -298,7 +297,7 @@ writing. Windows is not and will never be supported.
 
     .. code::
 
-        python3 python3-pip python3-dev imagemagick fonts-liberation optipng gnupg libpq-dev libmagic-dev mime-support libzbar0 poppler-utils
+        python3 python3-pip python3-dev imagemagick fonts-liberation gnupg libpq-dev libmagic-dev mime-support libzbar0 poppler-utils
 
     These dependencies are required for OCRmyPDF, which is used for text recognition.
 
@@ -730,8 +729,6 @@ configuring some options in paperless can help improve performance immensely:
 *   If you want to perform OCR on the device, consider using ``PAPERLESS_OCR_CLEAN=none``.
     This will speed up OCR times and use less memory at the expense of slightly worse
     OCR results.
-*   Set ``PAPERLESS_OPTIMIZE_THUMBNAILS`` to 'false' if you want faster consumption
-    times. Thumbnails will be about 20% larger.
 *   If using docker, consider setting ``PAPERLESS_WEBSERVER_WORKERS`` to
     1. This will save some memory.
 

paperless.conf.example

@@ -65,7 +65,6 @@
 #PAPERLESS_CONSUMER_SUBDIRS_AS_TAGS=false
 #PAPERLESS_CONSUMER_ENABLE_BARCODES=false
 #PAPERLESS_CONSUMER_ENABLE_BARCODES=PATCHT
-#PAPERLESS_OPTIMIZE_THUMBNAILS=true
 #PAPERLESS_PRE_CONSUME_SCRIPT=/path/to/an/arbitrary/script.sh
 #PAPERLESS_POST_CONSUME_SCRIPT=/path/to/an/arbitrary/script.sh
 #PAPERLESS_FILENAME_DATE_ORDER=YMD
@@ -84,4 +83,3 @@
 
 #PAPERLESS_CONVERT_BINARY=/usr/bin/convert
 #PAPERLESS_GS_BINARY=/usr/bin/gs
-#PAPERLESS_OPTIPNG_BINARY=/usr/bin/optipng

src/documents/checks.py

@@ -11,7 +11,6 @@ from documents.signals import document_consumer_declaration
 
 @register()
 def changed_password_check(app_configs, **kwargs):
-
     from documents.models import Document
     from paperless.db import GnuPG
 

src/documents/consumer.py

@@ -273,7 +273,7 @@ class Consumer(LoggingMixin):
 
             self.log("debug", f"Generating thumbnail for {self.filename}...")
             self._send_progress(70, 100, "WORKING", MESSAGE_GENERATING_THUMBNAIL)
-            thumbnail = document_parser.get_optimised_thumbnail(
+            thumbnail = document_parser.get_thumbnail(
                 self.path,
                 mime_type,
                 self.filename,

src/documents/management/commands/document_archiver.py

@@ -41,7 +41,7 @@ def handle_document(document_id):
     try:
         parser.parse(document.source_path, mime_type, document.get_public_filename())
 
-        thumbnail = parser.get_optimised_thumbnail(
+        thumbnail = parser.get_thumbnail(
             document.source_path,
             mime_type,
             document.get_public_filename(),

src/documents/management/commands/document_exporter.py

@@ -189,7 +189,7 @@ class Command(BaseCommand):
             original_target = os.path.join(self.target, original_name)
             document_dict[EXPORTER_FILE_NAME] = original_name
 
-            thumbnail_name = base_name + "-thumbnail.png"
+            thumbnail_name = base_name + "-thumbnail.webp"
             thumbnail_target = os.path.join(self.target, thumbnail_name)
             document_dict[EXPORTER_THUMBNAIL_NAME] = thumbnail_name
 

src/documents/management/commands/document_thumbnails.py

@@ -11,7 +11,7 @@ from ...parsers import get_parser_class_for_mime_type
 
 
 def _process_document(doc_in):
-    document = Document.objects.get(id=doc_in)
+    document: Document = Document.objects.get(id=doc_in)
     parser_class = get_parser_class_for_mime_type(document.mime_type)
 
     if parser_class:
@@ -21,7 +21,8 @@ def _process_document(doc_in):
         return
 
     try:
-        thumb = parser.get_optimised_thumbnail(
+
+        thumb = parser.get_thumbnail(
             document.source_path,
             document.mime_type,
             document.get_public_filename(),
@@ -69,7 +70,7 @@ class Command(BaseCommand):
         ids = [doc.id for doc in documents]
 
         # Note to future self: this prevents django from reusing database
-        # conncetions between processes, which is bad and does not work
+        # connections between processes, which is bad and does not work
         # with postgres.
         db.connections.close_all()
 

src/documents/migrations/1021_webp_thumbnail_conversion.py

@@ -0,0 +1,107 @@
+# Generated by Django 4.0.5 on 2022-06-11 15:40
+import logging
+import multiprocessing.pool
+import shutil
+import tempfile
+import time
+from pathlib import Path
+
+from django.conf import settings
+from django.db import migrations
+from documents.parsers import run_convert
+
+logger = logging.getLogger("paperless.migrations")
+
+
+def _do_convert(work_package):
+    existing_thumbnail, converted_thumbnail = work_package
+    try:
+
+        logger.info(f"Converting thumbnail: {existing_thumbnail}")
+
+        # Run actual conversion
+        run_convert(
+            density=300,
+            scale="500x5000>",
+            alpha="remove",
+            strip=True,
+            trim=False,
+            auto_orient=True,
+            input_file=f"{existing_thumbnail}[0]",
+            output_file=str(converted_thumbnail),
+        )
+
+        # Copy newly created thumbnail to thumbnail directory
+        shutil.copy(converted_thumbnail, existing_thumbnail.parent)
+
+        # Remove the PNG version
+        existing_thumbnail.unlink()
+
+        logger.info(
+            "Conversion to WebP completed, "
+            f"replaced {existing_thumbnail.name} with {converted_thumbnail.name}",
+        )
+
+    except Exception as e:
+        logger.error(f"Error converting thumbnail (existing file unchanged): {e}")
+
+
+def _convert_thumbnails_to_webp(apps, schema_editor):
+    start = time.time()
+
+    with tempfile.TemporaryDirectory() as tempdir:
+
+        work_packages = []
+
+        for file in Path(settings.THUMBNAIL_DIR).glob("*.png"):
+            existing_thumbnail = file.resolve()
+
+            # Change the existing filename suffix from png to webp
+            converted_thumbnail_name = existing_thumbnail.with_suffix(
+                ".webp",
+            ).name
+
+            # Create the expected output filename in the tempdir
+            converted_thumbnail = (
+                Path(tempdir) / Path(converted_thumbnail_name)
+            ).resolve()
+
+            # Package up the necessary info
+            work_packages.append(
+                (existing_thumbnail, converted_thumbnail),
+            )
+
+        if len(work_packages):
+
+            logger.info(
+                "\n\n"
+                "  This is a one-time only migration to convert thumbnails for all of your\n"
+                "  documents into WebP format.  If you have a lot of documents though, \n"
+                "  this may take a while, so a coffee break may be in order."
+                "\n",
+            )
+
+            with multiprocessing.pool.Pool(
+                processes=min(multiprocessing.cpu_count(), 4),
+                maxtasksperchild=4,
+            ) as pool:
+                pool.map(_do_convert, work_packages)
+
+        end = time.time()
+        duration = end - start
+
+    logger.info(f"Conversion completed in {duration:.3f}s")
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("documents", "1020_merge_20220518_1839"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            code=_convert_thumbnails_to_webp,
+            reverse_code=migrations.RunPython.noop,
+        ),
+    ]

src/documents/models.py

@@ -3,6 +3,7 @@ import logging
 import os
 import re
 from collections import OrderedDict
+from typing import Optional
 
 import dateutil.parser
 import pathvalidate
@@ -228,7 +229,7 @@ class Document(models.Model):
         verbose_name = _("document")
         verbose_name_plural = _("documents")
 
-    def __str__(self):
+    def __str__(self) -> str:
 
         # Convert UTC database time to local time
         created = datetime.date.isoformat(timezone.localdate(self.created))
@@ -242,7 +243,7 @@ class Document(models.Model):
         return res
 
     @property
-    def source_path(self):
+    def source_path(self) -> str:
         if self.filename:
             fname = str(self.filename)
         else:
@@ -257,11 +258,11 @@ class Document(models.Model):
         return open(self.source_path, "rb")
 
     @property
-    def has_archive_version(self):
+    def has_archive_version(self) -> bool:
         return self.archive_filename is not None
 
     @property
-    def archive_path(self):
+    def archive_path(self) -> Optional[str]:
         if self.has_archive_version:
             return os.path.join(settings.ARCHIVE_DIR, str(self.archive_filename))
         else:
@@ -271,7 +272,7 @@ class Document(models.Model):
     def archive_file(self):
         return open(self.archive_path, "rb")
 
-    def get_public_filename(self, archive=False, counter=0, suffix=None):
+    def get_public_filename(self, archive=False, counter=0, suffix=None) -> str:
         result = str(self)
 
         if counter:
@@ -292,12 +293,14 @@ class Document(models.Model):
         return get_default_file_extension(self.mime_type)
 
     @property
-    def thumbnail_path(self):
+    def thumbnail_path(self) -> str:
-        file_name = f"{self.pk:07}.png"
+        webp_file_name = f"{self.pk:07}.webp"
         if self.storage_type == self.STORAGE_TYPE_GPG:
-            file_name += ".gpg"
+            webp_file_name += ".gpg"
 
-        return os.path.join(settings.THUMBNAIL_DIR, file_name)
+        webp_file_path = os.path.join(settings.THUMBNAIL_DIR, webp_file_name)
+
+        return os.path.normpath(webp_file_path)
 
     @property
     def thumbnail_file(self):

src/documents/parsers.py

@@ -150,11 +150,14 @@ def run_convert(
 
 
 def get_default_thumbnail() -> str:
+    """
+    Returns the path to a generic thumbnail
+    """
     return os.path.join(os.path.dirname(__file__), "resources", "document.png")
 
 
 def make_thumbnail_from_pdf_gs_fallback(in_path, temp_dir, logging_group=None) -> str:
-    out_path = os.path.join(temp_dir, "convert_gs.png")
+    out_path = os.path.join(temp_dir, "convert_gs.webp")
 
     # if convert fails, fall back to extracting
     # the first PDF page as a PNG using Ghostscript
@@ -191,7 +194,7 @@ def make_thumbnail_from_pdf(in_path, temp_dir, logging_group=None) -> str:
     """
     The thumbnail of a PDF is just a 500px wide image of the first page.
     """
-    out_path = os.path.join(temp_dir, "convert.png")
+    out_path = os.path.join(temp_dir, "convert.webp")
 
     # Run convert to get a decent thumbnail
     try:
@@ -319,29 +322,6 @@ class DocumentParser(LoggingMixin):
         """
         raise NotImplementedError()
 
-    def get_optimised_thumbnail(self, document_path, mime_type, file_name=None):
-        thumbnail = self.get_thumbnail(document_path, mime_type, file_name)
-        if settings.OPTIMIZE_THUMBNAILS:
-            out_path = os.path.join(self.tempdir, "thumb_optipng.png")
-
-            args = (
-                settings.OPTIPNG_BINARY,
-                "-silent",
-                "-o5",
-                thumbnail,
-                "-out",
-                out_path,
-            )
-
-            self.log("debug", f"Execute: {' '.join(args)}")
-
-            if not subprocess.Popen(args).wait() == 0:
-                raise ParseError(f"Optipng failed at {args}")
-
-            return out_path
-        else:
-            return thumbnail
-
     def get_text(self):
         return self.text
 

src/documents/tests/test_api.py

@@ -176,7 +176,7 @@ class TestDocumentApi(DirectoriesMixin, APITestCase):
         )
 
         with open(
-            os.path.join(self.dirs.thumbnail_dir, f"{doc.pk:07d}.png"),
+            os.path.join(self.dirs.thumbnail_dir, f"{doc.pk:07d}.webp"),
             "wb",
         ) as f:
             f.write(content_thumbnail)
@@ -1022,7 +1022,7 @@ class TestDocumentApi(DirectoriesMixin, APITestCase):
             "samples",
             "documents",
             "thumbnails",
-            "0000001.png",
+            "0000001.webp",
         )
         archive_file = os.path.join(os.path.dirname(__file__), "samples", "simple.pdf")
 

src/documents/tests/test_consumer.py

@@ -180,10 +180,10 @@ class DummyParser(DocumentParser):
 
     def __init__(self, logging_group, scratch_dir, archive_path):
         super().__init__(logging_group, None)
-        _, self.fake_thumb = tempfile.mkstemp(suffix=".png", dir=scratch_dir)
+        _, self.fake_thumb = tempfile.mkstemp(suffix=".webp", dir=scratch_dir)
         self.archive_path = archive_path
 
-    def get_optimised_thumbnail(self, document_path, mime_type, file_name=None):
+    def get_thumbnail(self, document_path, mime_type, file_name=None):
         return self.fake_thumb
 
     def parse(self, document_path, mime_type, file_name=None):
@@ -194,12 +194,12 @@ class CopyParser(DocumentParser):
     def get_thumbnail(self, document_path, mime_type, file_name=None):
         return self.fake_thumb
 
-    def get_optimised_thumbnail(self, document_path, mime_type, file_name=None):
+    def get_thumbnail(self, document_path, mime_type, file_name=None):
         return self.fake_thumb
 
     def __init__(self, logging_group, progress_callback=None):
         super().__init__(logging_group, progress_callback)
-        _, self.fake_thumb = tempfile.mkstemp(suffix=".png", dir=self.tempdir)
+        _, self.fake_thumb = tempfile.mkstemp(suffix=".webp", dir=self.tempdir)
 
     def parse(self, document_path, mime_type, file_name=None):
         self.text = "The text"
@@ -214,9 +214,9 @@ class FaultyParser(DocumentParser):
 
     def __init__(self, logging_group, scratch_dir):
         super().__init__(logging_group)
-        _, self.fake_thumb = tempfile.mkstemp(suffix=".png", dir=scratch_dir)
+        _, self.fake_thumb = tempfile.mkstemp(suffix=".webp", dir=scratch_dir)
 
-    def get_optimised_thumbnail(self, document_path, mime_type, file_name=None):
+    def get_thumbnail(self, document_path, mime_type, file_name=None):
         return self.fake_thumb
 
     def parse(self, document_path, mime_type, file_name=None):
@@ -230,6 +230,8 @@ def fake_magic_from_file(file, mime=False):
             return "application/pdf"
         elif os.path.splitext(file)[1] == ".png":
             return "image/png"
+        elif os.path.splitext(file)[1] == ".webp":
+            return "image/webp"
         else:
             return "unknown"
     else:

src/documents/tests/test_management.py

@@ -150,9 +150,9 @@ class TestDecryptDocuments(TestCase):
                 "samples",
                 "documents",
                 "thumbnails",
-                f"0000004.png.gpg",
+                f"0000004.webp.gpg",
             ),
-            os.path.join(thumb_dir, f"{doc.id:07}.png.gpg"),
+            os.path.join(thumb_dir, f"{doc.id:07}.webp.gpg"),
         )
 
         call_command("decrypt_documents")
@@ -163,7 +163,7 @@ class TestDecryptDocuments(TestCase):
         self.assertEqual(doc.filename, "0000004.pdf")
         self.assertTrue(os.path.isfile(os.path.join(originals_dir, "0000004.pdf")))
         self.assertTrue(os.path.isfile(doc.source_path))
-        self.assertTrue(os.path.isfile(os.path.join(thumb_dir, f"{doc.id:07}.png")))
+        self.assertTrue(os.path.isfile(os.path.join(thumb_dir, f"{doc.id:07}.webp")))
         self.assertTrue(os.path.isfile(doc.thumbnail_path))
 
         with doc.source_file as f:

src/documents/tests/test_migration_webp_conversion.py

@@ -0,0 +1,231 @@
+import shutil
+import tempfile
+from pathlib import Path
+from typing import Callable
+from typing import Iterable
+from typing import Union
+from unittest import mock
+
+from django.test import override_settings
+from documents.tests.test_migration_archive_files import thumbnail_path
+from documents.tests.utils import TestMigrations
+
+
+@mock.patch(
+    "documents.migrations.1021_webp_thumbnail_conversion.multiprocessing.pool.Pool.map",
+)
+@mock.patch("documents.migrations.1021_webp_thumbnail_conversion.run_convert")
+class TestMigrateWebPThumbnails(TestMigrations):
+
+    migrate_from = "1020_merge_20220518_1839"
+    migrate_to = "1021_webp_thumbnail_conversion"
+    auto_migrate = False
+
+    def pretend_convert_output(self, *args, **kwargs):
+        """
+        Pretends to do the conversion, by copying the input file
+        to the output file
+        """
+        shutil.copy2(
+            Path(kwargs["input_file"].rstrip("[0]")),
+            Path(kwargs["output_file"]),
+        )
+
+    def pretend_map(self, func: Callable, iterable: Iterable):
+        """
+        Pretends to be the map of a multiprocessing.Pool, but secretly does
+        everything in series
+        """
+        for item in iterable:
+            func(item)
+
+    def create_dummy_thumbnails(
+        self,
+        thumb_dir: Path,
+        ext: str,
+        count: int,
+        start_count: int = 0,
+    ):
+        """
+        Helper to create a certain count of files of given extension in a given directory
+        """
+        for idx in range(count):
+            (Path(thumb_dir) / Path(f"{start_count + idx:07}.{ext}")).touch()
+        # Triple check expected files exist
+        self.assert_file_count_by_extension(ext, thumb_dir, count)
+
+    def create_webp_thumbnail_files(
+        self,
+        thumb_dir: Path,
+        count: int,
+        start_count: int = 0,
+    ):
+        """
+        Creates a dummy WebP thumbnail file in the given directory, based on
+        the database Document
+        """
+        self.create_dummy_thumbnails(thumb_dir, "webp", count, start_count)
+
+    def create_png_thumbnail_file(
+        self,
+        thumb_dir: Path,
+        count: int,
+        start_count: int = 0,
+    ):
+        """
+        Creates a dummy PNG thumbnail file in the given directory, based on
+        the database Document
+        """
+        self.create_dummy_thumbnails(thumb_dir, "png", count, start_count)
+
+    def assert_file_count_by_extension(
+        self,
+        ext: str,
+        dir: Union[str, Path],
+        expected_count: int,
+    ):
+        """
+        Helper to assert a certain count of given extension files in given directory
+        """
+        if not isinstance(dir, Path):
+            dir = Path(dir)
+        matching_files = list(dir.glob(f"*.{ext}"))
+        self.assertEqual(len(matching_files), expected_count)
+
+    def assert_png_file_count(self, dir: Path, expected_count: int):
+        """
+        Helper to assert a certain count of PNG extension files in given directory
+        """
+        self.assert_file_count_by_extension("png", dir, expected_count)
+
+    def assert_webp_file_count(self, dir: Path, expected_count: int):
+        """
+        Helper to assert a certain count of WebP extension files in given directory
+        """
+        self.assert_file_count_by_extension("webp", dir, expected_count)
+
+    def setUp(self):
+
+        self.thumbnail_dir = Path(tempfile.mkdtemp()).resolve()
+
+        return super().setUp()
+
+    def tearDown(self) -> None:
+
+        shutil.rmtree(self.thumbnail_dir)
+
+        return super().tearDown()
+
+    def test_do_nothing_if_converted(
+        self,
+        run_convert_mock: mock.MagicMock,
+        map_mock: mock.MagicMock,
+    ):
+        """
+        GIVEN:
+            - Document exists with default WebP thumbnail path
+        WHEN:
+            - Thumbnail conversion is attempted
+        THEN:
+            - Nothing is converted
+        """
+        map_mock.side_effect = self.pretend_map
+
+        with override_settings(
+            THUMBNAIL_DIR=self.thumbnail_dir,
+        ):
+
+            self.create_webp_thumbnail_files(self.thumbnail_dir, 3)
+
+            self.performMigration()
+            run_convert_mock.assert_not_called()
+
+            self.assert_webp_file_count(self.thumbnail_dir, 3)
+
+    def test_convert_single_thumbnail(
+        self,
+        run_convert_mock: mock.MagicMock,
+        map_mock: mock.MagicMock,
+    ):
+        """
+        GIVEN:
+            - Document exists with PNG thumbnail
+        WHEN:
+            - Thumbnail conversion is attempted
+        THEN:
+            - Single thumbnail is converted
+        """
+        map_mock.side_effect = self.pretend_map
+        run_convert_mock.side_effect = self.pretend_convert_output
+
+        with override_settings(
+            THUMBNAIL_DIR=self.thumbnail_dir,
+        ):
+            self.create_png_thumbnail_file(self.thumbnail_dir, 3)
+
+            self.performMigration()
+
+            run_convert_mock.assert_called()
+            self.assertEqual(run_convert_mock.call_count, 3)
+
+            self.assert_webp_file_count(self.thumbnail_dir, 3)
+
+    def test_convert_errors_out(
+        self,
+        run_convert_mock: mock.MagicMock,
+        map_mock: mock.MagicMock,
+    ):
+        """
+        GIVEN:
+            - Document exists with PNG thumbnail
+        WHEN:
+            - Thumbnail conversion is attempted, but raises an exception
+        THEN:
+            - Single thumbnail is converted
+        """
+        map_mock.side_effect = self.pretend_map
+        run_convert_mock.side_effect = OSError
+
+        with override_settings(
+            THUMBNAIL_DIR=self.thumbnail_dir,
+        ):
+
+            self.create_png_thumbnail_file(self.thumbnail_dir, 3)
+
+            self.performMigration()
+
+            run_convert_mock.assert_called()
+            self.assertEqual(run_convert_mock.call_count, 3)
+
+            self.assert_png_file_count(self.thumbnail_dir, 3)
+
+    def test_convert_mixed(
+        self,
+        run_convert_mock: mock.MagicMock,
+        map_mock: mock.MagicMock,
+    ):
+        """
+        GIVEN:
+            - Document exists with PNG thumbnail
+        WHEN:
+            - Thumbnail conversion is attempted, but raises an exception
+        THEN:
+            - Single thumbnail is converted
+        """
+        map_mock.side_effect = self.pretend_map
+        run_convert_mock.side_effect = self.pretend_convert_output
+
+        with override_settings(
+            THUMBNAIL_DIR=self.thumbnail_dir,
+        ):
+
+            self.create_png_thumbnail_file(self.thumbnail_dir, 3)
+            self.create_webp_thumbnail_files(self.thumbnail_dir, 2, start_count=3)
+
+            self.performMigration()
+
+            run_convert_mock.assert_called()
+            self.assertEqual(run_convert_mock.call_count, 3)
+
+            self.assert_png_file_count(self.thumbnail_dir, 0)
+            self.assert_webp_file_count(self.thumbnail_dir, 5)

src/documents/tests/test_parsers.py

@@ -87,31 +87,6 @@ def fake_get_thumbnail(self, path, mimetype, file_name):
     return os.path.join(os.path.dirname(__file__), "examples", "no-text.png")
 
 
-class TestBaseParser(TestCase):
-    def setUp(self) -> None:
-
-        self.scratch = tempfile.mkdtemp()
-        override_settings(SCRATCH_DIR=self.scratch).enable()
-
-    def tearDown(self) -> None:
-        shutil.rmtree(self.scratch)
-
-    @mock.patch("documents.parsers.DocumentParser.get_thumbnail", fake_get_thumbnail)
-    @override_settings(OPTIMIZE_THUMBNAILS=True)
-    def test_get_optimised_thumbnail(self):
-        parser = DocumentParser(None)
-
-        parser.get_optimised_thumbnail("any", "not important", "document.pdf")
-
-    @mock.patch("documents.parsers.DocumentParser.get_thumbnail", fake_get_thumbnail)
-    @override_settings(OPTIMIZE_THUMBNAILS=False)
-    def test_get_optimised_thumb_disabled(self):
-        parser = DocumentParser(None)
-
-        path = parser.get_optimised_thumbnail("any", "not important", "document.pdf")
-        self.assertEqual(path, fake_get_thumbnail(None, None, None, None))
-
-
 class TestParserAvailability(TestCase):
     def test_file_extensions(self):
 

src/documents/tests/test_sanity_check.py

@@ -42,9 +42,9 @@ class TestSanityCheck(DirectoriesMixin, TestCase):
                     "samples",
                     "documents",
                     "thumbnails",
-                    "0000001.png",
+                    "0000001.webp",
                 ),
-                os.path.join(self.dirs.thumbnail_dir, "0000001.png"),
+                os.path.join(self.dirs.thumbnail_dir, "0000001.webp"),
             )
 
         return Document.objects.create(

src/documents/views.py

@@ -362,7 +362,8 @@ class DocumentViewSet(
                 handle = doc.thumbnail_file
             # TODO: Send ETag information and use that to send new thumbnails
             #  if available
-            return HttpResponse(handle, content_type="image/png")
+
+            return HttpResponse(handle, content_type="image/webp")
         except (FileNotFoundError, Document.DoesNotExist):
             raise Http404()
 

src/paperless/checks.py

@@ -72,7 +72,7 @@ def binaries_check(app_configs, **kwargs):
     error = "Paperless can't find {}. Without it, consumption is impossible."
     hint = "Either it's not in your ${PATH} or it's not installed."
 
-    binaries = (settings.CONVERT_BINARY, settings.OPTIPNG_BINARY, "tesseract")
+    binaries = (settings.CONVERT_BINARY, "tesseract")
 
     check_messages = []
     for binary in binaries:

src/paperless/settings.py

@@ -526,8 +526,6 @@ CONSUMER_BARCODE_TIFF_SUPPORT = __get_boolean(
 
 CONSUMER_BARCODE_STRING = os.getenv("PAPERLESS_CONSUMER_BARCODE_STRING", "PATCHT")
 
-OPTIMIZE_THUMBNAILS = __get_boolean("PAPERLESS_OPTIMIZE_THUMBNAILS", "true")
-
 OCR_PAGES = int(os.getenv("PAPERLESS_OCR_PAGES", 0))
 
 # The default language that tesseract will attempt to use when parsing
@@ -570,8 +568,6 @@ CONVERT_MEMORY_LIMIT = os.getenv("PAPERLESS_CONVERT_MEMORY_LIMIT")
 
 GS_BINARY = os.getenv("PAPERLESS_GS_BINARY", "gs")
 
-OPTIPNG_BINARY = os.getenv("PAPERLESS_OPTIPNG_BINARY", "optipng")
-
 
 # Pre-2.x versions of Paperless stored your documents locally with GPG
 # encryption, but that is no longer the default.  This behaviour is still

src/paperless/tests/test_checks.py

@@ -13,9 +13,9 @@ class TestChecks(DirectoriesMixin, TestCase):
     def test_binaries(self):
         self.assertEqual(binaries_check(None), [])
 
-    @override_settings(CONVERT_BINARY="uuuhh", OPTIPNG_BINARY="forgot")
+    @override_settings(CONVERT_BINARY="uuuhh")
     def test_binaries_fail(self):
-        self.assertEqual(len(binaries_check(None)), 2)
+        self.assertEqual(len(binaries_check(None)), 1)
 
     def test_paths_check(self):
         self.assertEqual(paths_check(None), [])

src/paperless_text/parsers.py

@@ -30,8 +30,8 @@ class TextDocumentParser(DocumentParser):
         )
         draw.text((5, 5), read_text(), font=font, fill="black")
 
-        out_path = os.path.join(self.tempdir, "thumb.png")
+        out_path = os.path.join(self.tempdir, "thumb.webp")
-        img.save(out_path)
+        img.save(out_path, format="WEBP")
 
         return out_path