diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37619c8..dd48701 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,7 +58,7 @@ else()
     message(FATAL_ERROR "The conan_toolchain file could not be found: ${CONAN_TOOLCHAIN}")
 endif()
 
-project(apngasm-python VERSION 1.2.0)
+project(apngasm-python VERSION 1.2.1)
 set(PY_VERSION_SUFFIX "")
 set(PY_FULL_VERSION ${PROJECT_VERSION}${PY_VERSION_SUFFIX})
 
diff --git a/README.md b/README.md
index 71f189c..f6fc37d 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,11 @@ Documentations: https://apngasm-python.readthedocs.io/en/latest/
 pip install apngasm-python
 ```
 
+Optionally, you can also install `Pillow` and `numpy`
+```
+pip install Pillow numpy
+```
+
 ## Example usage
 The recommended usage is to `from apngasm_python.apngasm import APNGAsmBinder`, see [example/example_binder.py](example/example_binder.py)
 ```python
diff --git a/conanfile.py b/conanfile.py
index 974eb8a..1b8dedb 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -4,26 +4,31 @@
 from conan.tools.cmake import CMake, CMakeToolchain, CMakeDeps, cmake_layout
 from conan.tools.apple import is_apple_os
 
+
 class ApngasmRecipe(ConanFile):
-    settings = 'os', 'compiler', 'build_type', 'arch'
-    
+    settings = "os", "compiler", "build_type", "arch"
+
     def requirements(self):
         self.requires("zlib/1.2.13")
         self.requires("libpng/1.6.40")
-        self.requires("boost/1.75.0") # https://github.com/conan-io/conan-center-index/issues/19704
+        self.requires(
+            "boost/1.75.0"
+        )  # https://github.com/conan-io/conan-center-index/issues/19704
 
     def build_requirements(self):
         self.build_requires("b2/4.10.1")
-        if not shutil.which('cmake'):
+        if not shutil.which("cmake"):
             self.tool_requires("cmake/[>=3.27]")
-    
+
     def build(self):
-        build_type = 'Release'
-    
+        build_type = "Release"
+
     def generate(self):
         tc = CMakeToolchain(self)
         cmake = CMakeDeps(self)
-        if is_apple_os(self) and get_arch() == 'universal2':
-            tc.blocks['apple_system'].values['cmake_osx_architectures'] = 'x86_64; arm64'
+        if is_apple_os(self) and get_arch() == "universal2":
+            tc.blocks["apple_system"].values[
+                "cmake_osx_architectures"
+            ] = "x86_64; arm64"
         tc.generate()
-        cmake.generate()
\ No newline at end of file
+        cmake.generate()
diff --git a/docs/conf.py b/docs/conf.py
index bec27c8..4609efd 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -7,19 +7,19 @@
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
 import os
 
-project = 'apngasm-python'
-copyright = '2023, laggykiller'
-author = 'laggykiller'
+project = "apngasm-python"
+copyright = "2023, laggykiller"
+author = "laggykiller"
 
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
 
 extensions = [
-    'autoapi.extension',
-    'sphinx.ext.mathjax',
-    'sphinx.ext.napoleon',
-    'myst_parser',
-    'sphinx_immaterial'
+    "autoapi.extension",
+    "sphinx.ext.mathjax",
+    "sphinx.ext.napoleon",
+    "myst_parser",
+    "sphinx_immaterial",
 ]
 
 autosummary_generate = True
@@ -28,20 +28,20 @@
 napoleon_numpy_docstring = True
 napoleon_use_ivar = True
 
-templates_path = ['_templates']
-exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
+templates_path = ["_templates"]
+exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
 
 autoapi_dirs = [
-    os.path.abspath('../src-python/apngasm_python'),
-    os.path.abspath('../src-python/apngasm_python/_apngasm_python')
+    os.path.abspath("../src-python/apngasm_python"),
+    os.path.abspath("../src-python/apngasm_python/_apngasm_python"),
 ]
 autoapi_python_use_implicit_namespaces = True
 
 # -- Options for HTML output -------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
 
-html_theme = 'sphinx_immaterial'
-html_static_path = ['_static']
+html_theme = "sphinx_immaterial"
+html_static_path = ["_static"]
 # material theme options (see theme.conf for more information)
 html_theme_options = {
     "repo_name": "rlottie-python",
@@ -85,4 +85,4 @@
         },
     ],
     "toc_title_is_page_title": True,
-}
\ No newline at end of file
+}
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 25e759b..0a40d08 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,5 @@
 myst_parser
 sphinx-immaterial
-sphinx-autoapi
\ No newline at end of file
+sphinx-autoapi
+numpy
+Pillow
\ No newline at end of file
diff --git a/example/example_binder.py b/example/example_binder.py
index 4be8617..96f357e 100755
--- a/example/example_binder.py
+++ b/example/example_binder.py
@@ -6,80 +6,82 @@
 import numpy as np
 
 # Cleanup
-shutil.rmtree('output', ignore_errors=True)
-os.mkdir('output')
+shutil.rmtree("output", ignore_errors=True)
+os.mkdir("output")
 
 # Initialize
 apngasm = APNGAsmBinder()
 
 # Get libapngasm version
-print(f'{apngasm.version() = }')
+print(f"{apngasm.version() = }")
 
 # Load png from one directory
-for file_name in sorted(os.listdir('frames')):
-    apngasm.add_frame_from_file(os.path.join('frames', file_name), 100, 1000)
+for file_name in sorted(os.listdir("frames")):
+    apngasm.add_frame_from_file(os.path.join("frames", file_name), 100, 1000)
 
 # Getting information about one frame
 frame = apngasm.get_frames()[0]
 
 # Saving one frame as file
-frame.save('output/elephant-frame.png')
+frame.save("output/elephant-frame.png")
 
 # Getting one frame as Pillow Image
 im = apngasm.frame_pixels_as_pillow(0)
-im.save('output/elephant-frame-pillow.png')
+im.save("output/elephant-frame-pillow.png")
 
 # Get inforamtion about whole animation
-print(f'{apngasm.get_loops() = }')
-print(f'{apngasm.is_skip_first() = }')
-print(f'{apngasm.frame_count() = }')
+print(f"{apngasm.get_loops() = }")
+print(f"{apngasm.is_skip_first() = }")
+print(f"{apngasm.frame_count() = }")
 
 # Assemble
-success = apngasm.assemble('output/elephant.apng')
-print(f'{success = }')
+success = apngasm.assemble("output/elephant.apng")
+print(f"{success = }")
 
 # Clear images loaded in apngasm object
 apngasm.reset()
 
 # Disassemble and get pillow image of one frame
-frames = apngasm.disassemble_as_pillow('input/ball.apng')
+frames = apngasm.disassemble_as_pillow("input/ball.apng")
 frame = frames[0]
-frame.save('output/ball0.png')
+frame.save("output/ball0.png")
 
 # Disassemble all APNG into PNGs
-apngasm.save_pngs('output')
+apngasm.save_pngs("output")
 
 # Assemble from pillow images
 # Just for fun, let's also make it spin
 apngasm.reset()
 angle = 0
-angle_step = 360 / len(os.listdir('frames'))
-for file_name in sorted(os.listdir('frames')):
-    image = Image.open(os.path.join('frames', file_name))
+angle_step = 360 / len(os.listdir("frames"))
+for file_name in sorted(os.listdir("frames")):
+    image = Image.open(os.path.join("frames", file_name))
     image = image.rotate(angle)
     apngasm.add_frame_from_pillow(image)
-    
+
     angle += angle_step
 
-success = apngasm.assemble('output/elephant-spinning-pillow.apng')
-print(f'{success = }')
+success = apngasm.assemble("output/elephant-spinning-pillow.apng")
+print(f"{success = }")
 apngasm.reset()
 
 # Assemble palette and grey PNGs
 # You can use with statement to avoid calling reset()
 with APNGAsmBinder() as apng:
-    apng.add_frame_from_file('input/palette.png', delay_num=1, delay_den=1)
-    apng.add_frame_from_file('input/grey.png', delay_num=1, delay_den=1)
-    success = apng.assemble('output/birds.apng')
-    print(f'{success = }')
+    apng.add_frame_from_file("input/palette.png", delay_num=1, delay_den=1)
+    apng.add_frame_from_file("input/grey.png", delay_num=1, delay_den=1)
+    success = apng.assemble("output/birds.apng")
+    print(f"{success = }")
 
 # Assemble palette and grey PNGs, but with Pillow and numpy
-image0 = Image.open('input/grey.png')
+image0 = Image.open("input/grey.png")
 frame0 = apngasm.add_frame_from_pillow(image0, delay_num=1, delay_den=1)
-image1 = Image.open('input/grey.png').convert('RGB')
-frame1 = apngasm.add_frame_from_numpy(np.array(image1), trns_color=np.array([255, 255, 255]), delay_num=1, delay_den=1)
-image2 = Image.open('input/palette.png')
+image1 = Image.open("input/grey.png").convert("RGB")
+frame1 = apngasm.add_frame_from_numpy(
+    np.array(image1), trns_color=np.array([255, 255, 255]), delay_num=1, delay_den=1
+)
+image2 = Image.open("input/palette.png")
 apngasm.add_frame_from_pillow(image2, delay_num=1, delay_den=1)
 
-success = apngasm.assemble('output/birds-pillow.apng')
-print(f'{success = }')
\ No newline at end of file
+success = apngasm.assemble("output/birds-pillow.apng")
+print(f"{success = }")
diff --git a/example/example_direct.py b/example/example_direct.py
index 99a223c..2f6827e 100755
--- a/example/example_direct.py
+++ b/example/example_direct.py
@@ -1,103 +1,105 @@
 #!/usr/bin/env python3
-from apngasm_python._apngasm_python import APNGAsm, APNGFrame, create_frame_from_rgb, create_frame_from_rgb_trns, create_frame_from_rgba
+from apngasm_python._apngasm_python import (
+    APNGAsm,
+    APNGFrame,
+    create_frame_from_rgb,
+    create_frame_from_rgb_trns,
+    create_frame_from_rgba,
+)
 import os
 import shutil
 from PIL import Image
 import numpy as np
 
+
 def frame_info(frame):
-    print(f'{frame.pixels = }')
-    print(f'{frame.width = }')
-    print(f'{frame.height = }')
-    print(f'{frame.color_type = }')
-    print(f'{frame.palette = }')
-    print(f'{frame.transparency = }')
-    print(f'{frame.palette_size = }')
-    print(f'{frame.transparency_size = }')
-    print(f'{frame.delay_num = }')
-    print(f'{frame.delay_den = }')
+    print(f"{frame.pixels = }")
+    print(f"{frame.width = }")
+    print(f"{frame.height = }")
+    print(f"{frame.color_type = }")
+    print(f"{frame.palette = }")
+    print(f"{frame.transparency = }")
+    print(f"{frame.palette_size = }")
+    print(f"{frame.transparency_size = }")
+    print(f"{frame.delay_num = }")
+    print(f"{frame.delay_den = }")
+
 
 # https://www.w3.org/TR/PNG-Chunks.html
-color_type_dict = {
-    0: 'L',
-    2: 'RGB',
-    3: 'P',
-    4: 'LA',
-    6: 'RGBA'
-}
+color_type_dict = {0: "L", 2: "RGB", 3: "P", 4: "LA", 6: "RGBA"}
 
 color_type_dict.update(dict((v, k) for k, v in color_type_dict.items()))
 
 # Cleanup
-shutil.rmtree('output', ignore_errors=True)
-os.mkdir('output')
+shutil.rmtree("output", ignore_errors=True)
+os.mkdir("output")
 
 # Initialize
 apngasm = APNGAsm()
 
 # Get libapngasm version
-print(f'{apngasm.version() = }')
+print(f"{apngasm.version() = }")
 
 # Load png from one directory
-for file_name in sorted(os.listdir('frames')):
-    apngasm.add_frame_from_file(os.path.join('frames', file_name), 100, 1000)
+for file_name in sorted(os.listdir("frames")):
+    apngasm.add_frame_from_file(os.path.join("frames", file_name), 100, 1000)
 
 # Getting information about one frame
 frame = apngasm.get_frames()[0]
 frame_info(frame)
 
 # Saving one frame as file
-frame.save('output/elephant-frame.png')
+frame.save("output/elephant-frame.png")
 
 # Getting one frame as Pillow Image
 mode = color_type_dict[frame.color_type]
 im = Image.frombytes(mode, (frame.width, frame.height), frame.pixels)
-im.save('output/elephant-frame-pillow.png')
+im.save("output/elephant-frame-pillow.png")
 
 # Get inforamtion about whole animation
-print(f'{apngasm.get_loops() = }')
-print(f'{apngasm.is_skip_first() = }')
-print(f'{apngasm.frame_count() = }')
+print(f"{apngasm.get_loops() = }")
+print(f"{apngasm.is_skip_first() = }")
+print(f"{apngasm.frame_count() = }")
 
 # Assemble
-success = apngasm.assemble('output/elephant.apng')
-print(f'{success = }')
+success = apngasm.assemble("output/elephant.apng")
+print(f"{success = }")
 
 # Clear images loaded in apngasm object
 apngasm.reset()
 
 # Disassemble and get pillow image of one frame
-frames = apngasm.disassemble('input/ball.apng')
-print(f'{len(frames) = }')
+frames = apngasm.disassemble("input/ball.apng")
+print(f"{len(frames) = }")
 frame = frames[0]
 frame_info(frame)
 mode = color_type_dict[frame.color_type]
 im = Image.frombytes(mode, (frame.width, frame.height), frame.pixels)
-im.save('output/ball0.png')
+im.save("output/ball0.png")
 
 # Disassemble all APNG into PNGs
-apngasm.save_pngs('output')
+apngasm.save_pngs("output")
 
 # Assemble from pillow images
 # Just for fun, let's also make it spin
 apngasm.reset()
 angle = 0
-angle_step = 360 / len(os.listdir('frames'))
-for file_name in sorted(os.listdir('frames')):
-    image = Image.open(os.path.join('frames', file_name))
+angle_step = 360 / len(os.listdir("frames"))
+for file_name in sorted(os.listdir("frames")):
+    image = Image.open(os.path.join("frames", file_name))
     image = image.rotate(angle)
     frame = create_frame_from_rgba(np.array(image), image.width, image.height)
     apngasm.add_frame(frame)
-    
+
     angle += angle_step
 
-success = apngasm.assemble('output/elephant-spinning-pillow.apng')
-print(f'{success = }')
+success = apngasm.assemble("output/elephant-spinning-pillow.apng")
+print(f"{success = }")
 
 # Assemble palette and grey PNGs
 apngasm.reset()
-apngasm.add_frame_from_file('input/palette.png', 100, 1000)
-apngasm.add_frame_from_file('input/grey.png', 100, 1000)
+apngasm.add_frame_from_file("input/palette.png", 100, 1000)
+apngasm.add_frame_from_file("input/grey.png", 100, 1000)
 
 frame0 = apngasm.get_frames()[0]
 frame_info(frame0)
@@ -105,22 +107,24 @@ def frame_info(frame):
 frame1 = apngasm.get_frames()[1]
 frame_info(frame1)
 
-success = apngasm.assemble('output/birds.apng')
-print(f'{success = }')
+success = apngasm.assemble("output/birds.apng")
+print(f"{success = }")
 
 del apngasm
 
 # Assemble palette and grey PNGs, but with Pillow
-image0 = Image.open('input/grey.png').convert('RGB')
+image0 = Image.open("input/grey.png").convert("RGB")
 frame0 = create_frame_from_rgb(np.array(image0), image0.width, image0.height, 1, 1)
 frame_info(frame0)
 
-image1 = Image.open('input/grey.png').convert('RGB')
-frame1 = create_frame_from_rgb_trns(np.array(image1), image0.width, image0.height, np.array([255, 255, 255]), 1, 1)
+image1 = Image.open("input/grey.png").convert("RGB")
+frame1 = create_frame_from_rgb_trns(
+    np.array(image1), image0.width, image0.height, np.array([255, 255, 255]), 1, 1
+)
 frame_info(frame1)
 
 # You may even set the variables manually
-image2 = Image.open('input/palette.png').convert('RGBA')
+image2 = Image.open("input/palette.png").convert("RGBA")
 frame2 = APNGFrame()
 frame2.delay_num = 1
 frame2.delay_den = 1
@@ -133,5 +137,5 @@ def frame_info(frame):
 # Another way of creating APNGAsm object
 apngasm = APNGAsm([frame0, frame1, frame2])
 
-success = apngasm.assemble('output/birds-pillow.apng')
-print(f'{success = }')
\ No newline at end of file
+success = apngasm.assemble("output/birds-pillow.apng")
+print(f"{success = }")
diff --git a/pyproject.toml b/pyproject.toml
index e7bb812..8165d86 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ license = { "file" = "LICENSE" }
 authors = [{ "name" = "chaudominic", "email" = "chaudominic2@gmail.com" }]
 keywords = ["apng", "png", "nanobind", "pybind11"]
 classifiers = ["Topic :: Multimedia :: Graphics"]
-dependencies = ["Pillow", "numpy"]
+dependencies = []
 dynamic = ["version"]
 
 [project.urls]
diff --git a/requirements.txt b/requirements.txt
deleted file mode 100644
index e06245b..0000000
--- a/requirements.txt
+++ /dev/null
@@ -1,2 +0,0 @@
-Pillow
-numpy
\ No newline at end of file
diff --git a/scripts/get_arch.py b/scripts/get_arch.py
index 123bf74..8689e4f 100755
--- a/scripts/get_arch.py
+++ b/scripts/get_arch.py
@@ -4,17 +4,18 @@
 import platform
 
 conan_archs = {
-    'x86_64': ['amd64', 'x86_64', 'x64'],
-    'x86': ['i386', 'i686', 'x86'],
-    'armv8': ['arm64', 'aarch64', 'aarch64_be', 'armv8b', 'armv8l'],
-    'ppc64le': ['ppc64le', 'powerpc'],
-    's390x': ['s390', 's390x']
+    "x86_64": ["amd64", "x86_64", "x64"],
+    "x86": ["i386", "i686", "x86"],
+    "armv8": ["arm64", "aarch64", "aarch64_be", "armv8b", "armv8l"],
+    "ppc64le": ["ppc64le", "powerpc"],
+    "s390x": ["s390", "s390x"],
 }
 
+
 def get_arch():
     arch = None
-    if os.getenv('APNGASM_COMPILE_TARGET'):
-        arch = os.getenv('APNGASM_COMPILE_TARGET')
+    if os.getenv("APNGASM_COMPILE_TARGET"):
+        arch = os.getenv("APNGASM_COMPILE_TARGET")
     else:
         for k, v in conan_archs.items():
             if platform.machine().lower() in v:
@@ -23,15 +24,17 @@ def get_arch():
 
     if arch == None:
         arch = platform.machine().lower()
-    
+
     return arch
 
+
 def main():
     arch = get_arch()
-    if os.getenv('APNGASM_COMPILE_TARGET'):
-        sys.stdout.write(os.getenv('APNGASM_COMPILE_TARGET'))
+    if os.getenv("APNGASM_COMPILE_TARGET"):
+        sys.stdout.write(os.getenv("APNGASM_COMPILE_TARGET"))
     else:
         sys.stdout.write(arch)
 
-if __name__ == '__main__':
-    main()
\ No newline at end of file
+
+if __name__ == "__main__":
+    main()
diff --git a/scripts/get_deps.py b/scripts/get_deps.py
index afe2c96..64266d2 100755
--- a/scripts/get_deps.py
+++ b/scripts/get_deps.py
@@ -11,84 +11,98 @@
 
 from scripts.get_arch import conan_archs, get_arch
 
+
 def install_deps(arch):
     # Use Conan to install dependencies
     settings = []
 
-    if platform.system() == 'Windows':
-        settings.append('os=Windows')
-    elif platform.system() == 'Darwin':
-        settings.append('os=Macos')
-        if arch == 'x86_64':
-            settings.append('os.version=10.15')
+    if platform.system() == "Windows":
+        settings.append("os=Windows")
+    elif platform.system() == "Darwin":
+        settings.append("os=Macos")
+        if arch == "x86_64":
+            settings.append("os.version=10.15")
         else:
-            settings.append('os.version=11.0')
-        settings.append('compiler=apple-clang')
-        settings.append('compiler.libcxx=libc++')
-    elif platform.system() == 'Linux':
-        settings.append('os=Linux')
-        settings.append('compiler=gcc')
-        settings.append('compiler.version=10')
-        settings.append('compiler.libcxx=libstdc++')
+            settings.append("os.version=11.0")
+        settings.append("compiler=apple-clang")
+        settings.append("compiler.libcxx=libc++")
+    elif platform.system() == "Linux":
+        settings.append("os=Linux")
+        settings.append("compiler=gcc")
+        settings.append("compiler.version=10")
+        settings.append("compiler.libcxx=libstdc++")
     if arch:
-        settings.append('arch=' + arch)
+        settings.append("arch=" + arch)
 
     build = []
-    if (platform.system() == 'Linux'):
+    if platform.system() == "Linux":
         # Need to compile dependencies if Linux
-        build.append('*')
-    elif (not shutil.which('cmake') and 
-        (platform.architecture()[0] == '32bit' or 
-        platform.machine().lower() not in (conan_archs['armv8'] + conan_archs['x86']))):
+        build.append("*")
+    elif not shutil.which("cmake") and (
+        platform.architecture()[0] == "32bit"
+        or platform.machine().lower() not in (conan_archs["armv8"] + conan_archs["x86"])
+    ):
+        build.append("cmake*")
 
-        build.append('cmake*')
-    
     if build == []:
-        build.append('missing')
-    
-    print('conan cli settings:')
-    print('settings: ' + str(settings))
-    print('build: ' + str(build))
-    
-    subprocess.run(['conan', 'profile', 'detect'])
-
-    conan_output = os.path.join('conan_output', arch)
-
-    subprocess.run([
-                    'conan', 'install', 
-                    *[x for s in settings for x in ('-s', s)],
-                    *[x for b in build for x in ('-b', b)], 
-                    '-of', conan_output, '--deployer=direct_deploy', '.'
-                    ])
-    
+        build.append("missing")
+
+    print("conan cli settings:")
+    print("settings: " + str(settings))
+    print("build: " + str(build))
+
+    subprocess.run(["conan", "profile", "detect"])
+
+    conan_output = os.path.join("conan_output", arch)
+
+    subprocess.run(
+        [
+            "conan",
+            "install",
+            *[x for s in settings for x in ("-s", s)],
+            *[x for b in build for x in ("-b", b)],
+            "-of",
+            conan_output,
+            "--deployer=direct_deploy",
+            ".",
+        ]
+    )
+
     return conan_output
 
+
 def main():
     arch = get_arch()
-    if arch == 'universal2':
-        conan_output = 'conan_output/x86_64'
+    if arch == "universal2":
+        conan_output = "conan_output/x86_64"
     else:
-        conan_output = 'conan_output/' + arch
+        conan_output = "conan_output/" + arch
     if os.path.isdir(conan_output):
-        print('Dependencies found at:' + conan_output)
-        print('Skip conan install...')
+        print("Dependencies found at:" + conan_output)
+        print("Skip conan install...")
         return
 
-    if arch != 'universal2':
+    if arch != "universal2":
         conan_output = install_deps(arch)
     else:
         # Repeat to install the other architecture version of libwebp
-        conan_output_x64 = install_deps('x86_64')
-        conan_output_arm = install_deps('armv8')
-        conan_output_universal2 = conan_output_arm.replace('armv8', 'universal2')
+        conan_output_x64 = install_deps("x86_64")
+        conan_output_arm = install_deps("armv8")
+        conan_output_universal2 = conan_output_arm.replace("armv8", "universal2")
         shutil.rmtree(conan_output_universal2, ignore_errors=True)
-        subprocess.run([
-                        'python3', 'lipo-dir-merge/lipo-dir-merge.py', 
-                        conan_output_x64, conan_output_arm, conan_output_universal2
-                        ])
+        subprocess.run(
+            [
+                "python3",
+                "lipo-dir-merge/lipo-dir-merge.py",
+                conan_output_x64,
+                conan_output_arm,
+                conan_output_universal2,
+            ]
+        )
 
         shutil.rmtree(conan_output_x64)
         shutil.move(conan_output_universal2, conan_output_x64)
 
-if __name__ == '__main__':
-    main()
\ No newline at end of file
+
+if __name__ == "__main__":
+    main()
diff --git a/scripts/patch_stub.py b/scripts/patch_stub.py
index 4f322ad..be93867 100755
--- a/scripts/patch_stub.py
+++ b/scripts/patch_stub.py
@@ -1,20 +1,24 @@
 #!/usr/bin/env python3
 import sys
 
+
 def main():
     init_pyi_path = sys.argv[1]
     with open(init_pyi_path) as f:
         init_pyi = f.read()
-    
-    with open(init_pyi_path, 'w+') as f:
-        init_pyi = init_pyi.replace('List[', 'list[')
-        if 'from __future__ import annotations' not in init_pyi:
-            f.write('from __future__ import annotations\n')
-        if 'import numpy.typing' not in init_pyi:
-            f.write('import numpy.typing\n')
-        if 'from . import _apngasm_python' not in init_pyi:
-            init_pyi = init_pyi.replace('import _apngasm_python', 'from . import _apngasm_python')
+
+    with open(init_pyi_path, "w+") as f:
+        init_pyi = init_pyi.replace("List[", "list[")
+        if "from __future__ import annotations" not in init_pyi:
+            f.write("from __future__ import annotations\n")
+        if "import numpy.typing" not in init_pyi:
+            f.write("import numpy.typing\n")
+        if "from . import _apngasm_python" not in init_pyi:
+            init_pyi = init_pyi.replace(
+                "import _apngasm_python", "from . import _apngasm_python"
+            )
         f.write(init_pyi)
 
-if __name__ == '__main__':
-    main()
\ No newline at end of file
+
+if __name__ == "__main__":
+    main()
diff --git a/scripts/update_stub.py b/scripts/update_stub.py
index 5db4852..e127392 100755
--- a/scripts/update_stub.py
+++ b/scripts/update_stub.py
@@ -3,31 +3,33 @@
 import shutil
 import zipfile
 
+
 def main():
-    py_bin = shutil.which('python3')
+    py_bin = shutil.which("python3")
     if not py_bin:
-        py_bin = shutil.which('python')
-    
-    dist_dir = os.path.join(os.path.split(os.path.abspath(__file__))[0], '../dist')
+        py_bin = shutil.which("python")
+
+    dist_dir = os.path.join(os.path.split(os.path.abspath(__file__))[0], "../dist")
 
     shutil.rmtree(dist_dir, ignore_errors=True)
-    os.chdir(os.path.join(os.path.split(os.path.abspath(__file__))[0], '../'))
-    os.system(py_bin + ' -m build .')
+    os.chdir(os.path.join(os.path.split(os.path.abspath(__file__))[0], "../"))
+    os.system(py_bin + " -m build .")
 
     for zip_file in os.listdir(dist_dir):
-        if os.path.splitext(zip_file)[1] != '.whl':
+        if os.path.splitext(zip_file)[1] != ".whl":
             continue
         zip_path = os.path.join(dist_dir, zip_file)
         with zipfile.ZipFile(zip_path, mode="r") as archive:
             for file in archive.namelist():
-                if os.path.splitext(file)[1] != '.pyi':
+                if os.path.splitext(file)[1] != ".pyi":
                     continue
-                dest_path = os.path.join('src-python', file)
+                dest_path = os.path.join("src-python", file)
                 dest_dir = os.path.split(dest_path)[0]
                 if not os.path.isdir(dest_dir):
                     os.makedirs(dest_dir)
-                with open(dest_path, 'wb+') as f:
+                with open(dest_path, "wb+") as f:
                     f.write(archive.read(file))
 
-if __name__ == '__main__':
-    main()
\ No newline at end of file
+
+if __name__ == "__main__":
+    main()
diff --git a/src-python/apngasm_python/__init__.py b/src-python/apngasm_python/__init__.py
index 95a7685..90a626c 100755
--- a/src-python/apngasm_python/__init__.py
+++ b/src-python/apngasm_python/__init__.py
@@ -1,2 +1,3 @@
-'''apngasm-python'''
-__version__ = '1.2.0'
\ No newline at end of file
+#!/usr/bin/env python3
+"""apngasm-python"""
+__version__ = "1.2.1"
diff --git a/src-python/apngasm_python/apngasm.py b/src-python/apngasm_python/apngasm.py
index 1bb2ee6..8d60e60 100755
--- a/src-python/apngasm_python/apngasm.py
+++ b/src-python/apngasm_python/apngasm.py
@@ -1,104 +1,138 @@
 #!/usr/bin/env python3
 from __future__ import annotations
-from ._apngasm_python import APNGAsm, APNGFrame, IAPNGAsmListener, create_frame_from_rgb, create_frame_from_rgb_trns, create_frame_from_rgba
+from ._apngasm_python import (
+    APNGAsm,
+    APNGFrame,
+    IAPNGAsmListener,
+    create_frame_from_rgb,
+    create_frame_from_rgb_trns,
+    create_frame_from_rgba,
+)
 from ._apngasm_python import __version__
-import numpy as np
-import numpy.typing
-from PIL import Image
+
+try:
+    import numpy
+    import numpy.typing
+
+    NUMPY_LOADED = True
+except ModuleNotFoundError:
+    NUMPY_LOADED = False
+
+try:
+    from PIL import Image
+
+    PILLOW_LOADED = True
+except ModuleNotFoundError:
+    PILLOW_LOADED = False
+
 from typing import Optional
 
+
 class APNGAsmBinder:
-    '''
+    """
     Python class for binding apngasm library
-    '''
-    
+    """
+
     # https://www.w3.org/TR/PNG-Chunks.html
-    color_type_dict = {
-        0: 'L',
-        2: 'RGB',
-        3: 'P',
-        4: 'LA',
-        6: 'RGBA'
-    }
+    color_type_dict = {0: "L", 2: "RGB", 3: "P", 4: "LA", 6: "RGBA"}
 
     def __init__(self):
         self.apngasm = APNGAsm()
-    
+
     def __enter__(self):
         return self
-    
+
     def __exit__(self, exc_type, exc_val, exc_tb):
         self.apngasm.reset()
-    
-    def frame_pixels_as_pillow(self, frame: int, new_value: Optional[Image.Image] = None) -> Optional[Image.Image]:
-        '''
-        Get/Set the raw pixel data of frame, expressed as a Pillow object.
-        This should be set AFTER you set the width, height and color_type.
-        
-        :param int frame: Target frame number.
-        :param Optional[PIL.Image.Image] new_value: If set, then the raw pixel data of frame 
-            is set with this value.
-        
-        :return: Pillow image object of the frame (get) or None (set)
-        :rtype: Optional[PIL.Image.Image]
-        '''
-        if new_value:
-            self.apngasm.get_frames()[frame].pixels = np.array(new_value)
-        else:
-            mode = self.color_type_dict[self.apngasm.get_frames()[frame].color_type]
-            return Image.frombytes(mode, (self.apngasm.get_frames()[frame].width, self.apngasm.get_frames()[frame].height), self.apngasm.get_frames()[frame].pixels)
-    
-    def frame_pixels_as_numpy(self, frame: int, new_value: Optional[numpy.typing.NDArray] = None) -> Optional[numpy.typing.NDArray]:
-        '''
-        Get/Set the raw pixel data of frame, expressed as a 3D numpy array.
-        This should be set AFTER you set the width, height and color_type.
 
-        :param int frame: Target frame number.
-        :param Optional[numpy.typing.NDArray] new_value: If set, then the raw pixel data of frame 
-            is set with this value.
+    if PILLOW_LOADED:
+
+        def frame_pixels_as_pillow(
+            self, frame: int, new_value: Optional[Image.Image] = None
+        ) -> Optional[Image.Image]:
+            """
+            Get/Set the raw pixel data of frame, expressed as a Pillow object.
+            This should be set AFTER you set the width, height and color_type.
+
+            :param int frame: Target frame number.
+            :param Optional[PIL.Image.Image] new_value: If set, then the raw pixel data of frame
+                is set with this value.
+
+            :return: Pillow image object of the frame (get) or None (set)
+            :rtype: Optional[PIL.Image.Image]
+            """
+            if new_value:
+                self.apngasm.get_frames()[frame].pixels = numpy.array(new_value)
+            else:
+                mode = self.color_type_dict[self.apngasm.get_frames()[frame].color_type]
+                return Image.frombytes(
+                    mode,
+                    (
+                        self.apngasm.get_frames()[frame].width,
+                        self.apngasm.get_frames()[frame].height,
+                    ),
+                    self.apngasm.get_frames()[frame].pixels,
+                )
+
+    if NUMPY_LOADED:
+
+        def frame_pixels_as_numpy(
+            self, frame: int, new_value: Optional[numpy.typing.NDArray] = None
+        ) -> Optional[numpy.typing.NDArray]:
+            """
+            Get/Set the raw pixel data of frame, expressed as a 3D numpy array.
+            This should be set AFTER you set the width, height and color_type.
+
+            :param int frame: Target frame number.
+            :param Optional[numpy.typing.NDArray] new_value: If set, then the raw pixel data of frame
+                is set with this value.
+
+            :return: 3D numpy array representation of raw pixel data of frame (get) or None (set)
+            :rtype: Optional[numpy.typing.NDArray]
+            """
+            if new_value:
+                self.apngasm.get_frames()[frame].pixels = new_value
+            else:
+                return self.apngasm.get_frames()[frame].pixels
 
-        :return: 3D numpy array representation of raw pixel data of frame (get) or None (set)
-        :rtype: Optional[numpy.typing.NDArray]
-        '''
-        if new_value:
-            self.apngasm.get_frames()[frame].pixels = new_value
-        else:
-            return self.apngasm.get_frames()[frame].pixels
-    
     def frame_width(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+        """
         Get/Set the width of frame.
-        
+
         :param int frame: Target frame number.
-        :param Optional[int] new_value: If set, then the width of frame 
+        :param Optional[int] new_value: If set, then the width of frame
             is set with this value.
 
         :return: width (get) or None (set)
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].width = new_value
         else:
             return self.apngasm.get_frames()[frame].width
-    
-    def frame_height(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+
+    def frame_height(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the height of frame.
-        
+
         :param int frame: Target frame number.
-        :param Optional[int] new_value: If set, then the height of frame 
+        :param Optional[int] new_value: If set, then the height of frame
             is set with this value.
 
         :return: height (get) or None (set)
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].height = new_value
         else:
             return self.apngasm.get_frames()[frame].height
-        
-    def frame_color_type(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+
+    def frame_color_type(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the color_type of frame.
 
         0: Grayscale (Pillow mode='L')
@@ -106,278 +140,316 @@ def frame_color_type(self, frame: int, new_value: Optional[int] = None) -> Optio
         3: Palette (Pillow mode='P')
         4: Grayscale + Alpha (Pillow mode='LA')
         6: RGBA (Pillow mode='RGBA')
-        
+
         :param int frame: Target frame number.
-        :param Optional[int] new_value: If set, then the color type of frame 
+        :param Optional[int] new_value: If set, then the color type of frame
             is set with this value.
-        
+
         :return: color_type of frame (get) or None (set)
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].color_type = new_value
         else:
             return self.apngasm.get_frames()[frame].color_type
-    
-    def frame_palette(self, frame: int, new_value: Optional[numpy.typing.NDArray] = None) -> Optional[numpy.typing.NDArray]:
-        '''
-        Get/Set the palette data of frame. Only applies to 'P' mode Image (i.e. Not RGB, RGBA)
-        Expressed as 2D numpy array in format of [[r0, g0, b0], [r1, g1, b1], ..., [r255, g255, b255]]
-        
-        :param int frame: Target frame number.
-        :param Optional[numpy.typing.NDArray] new_value: If set, then the palette data of frame 
-            is set with this value.
 
-        :return: 2D numpy array representation of palette data of frame (get) or None (set)
-        :rtype: Optional[numpy.typing.NDArray]
-        '''
-        if new_value:
-            self.apngasm.get_frames()[frame].palette = new_value
-        else:
-            return self.apngasm.get_frames()[frame].palette
+    if NUMPY_LOADED:
 
-    def frame_transparency(self, frame: int, new_value: Optional[numpy.typing.NDArray] = None) -> Optional[numpy.typing.NDArray]:
-        '''
-        Get/Set the color [r, g, b] to be treated as transparent in the frame, expressed as 1D numpy array.
-        For more info, refer to 'tRNS Transparency' in http://www.libpng.org/pub/png/spec/1.2/PNG-Chunks.html
-        
-        :param int frame: Target frame number.
-        :param Optional[numpy.typing.NDArray] new_value: If set, then the transparency of frame 
-            is set with this value.
+        def frame_palette(
+            self, frame: int, new_value: Optional[numpy.typing.NDArray] = None
+        ) -> Optional[numpy.typing.NDArray]:
+            """
+            Get/Set the palette data of frame. Only applies to 'P' mode Image (i.e. Not RGB, RGBA)
+            Expressed as 2D numpy array in format of [[r0, g0, b0], [r1, g1, b1], ..., [r255, g255, b255]]
 
-        :return: The color [r, g, b] to be treated as transparent in the frame (get) or None (set)
-        :rtype: Optional[numpy.typing.NDArray]
-        '''
-        if new_value:
-            self.apngasm.get_frames()[frame].transparency = new_value
-        else:
-            return self.apngasm.get_frames()[frame].transparency
+            :param int frame: Target frame number.
+            :param Optional[numpy.typing.NDArray] new_value: If set, then the palette data of frame
+                is set with this value.
 
-    def frame_palette_size(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+            :return: 2D numpy array representation of palette data of frame (get) or None (set)
+            :rtype: Optional[numpy.typing.NDArray]
+            """
+            if new_value:
+                self.apngasm.get_frames()[frame].palette = new_value
+            else:
+                return self.apngasm.get_frames()[frame].palette
+
+        def frame_transparency(
+            self, frame: int, new_value: Optional[numpy.typing.NDArray] = None
+        ) -> Optional[numpy.typing.NDArray]:
+            """
+            Get/Set the color [r, g, b] to be treated as transparent in the frame, expressed as 1D numpy array.
+            For more info, refer to 'tRNS Transparency' in
+            http://www.libpng.org/pub/png/spec/1.2/PNG-Chunks.html
+
+            :param int frame: Target frame number.
+            :param Optional[numpy.typing.NDArray] new_value: If set, then the transparency of frame
+                is set with this value.
+
+            :return: The color [r, g, b] to be treated as transparent in the frame (get) or None (set)
+            :rtype: Optional[numpy.typing.NDArray]
+            """
+            if new_value:
+                self.apngasm.get_frames()[frame].transparency = new_value
+            else:
+                return self.apngasm.get_frames()[frame].transparency
+
+    def frame_palette_size(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the palette data size of frame.
-        
+
         :param int frame: Target frame number.
-        :param Optional[int] new_value: If set, then the palette data size of frame 
+        :param Optional[int] new_value: If set, then the palette data size of frame
             is set with this value.
 
         :return: Palette data size of frame (get) or None (set)
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].palette_size = new_value
         else:
             return self.apngasm.get_frames()[frame].palette_size
-    
-    def frame_transparency_size(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+
+    def frame_transparency_size(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the transparency data size of frame.
-        
+
         :param int frame: Target frame number.
-        :param Optional[int] new_value: If set, then the transparency data size of frame 
+        :param Optional[int] new_value: If set, then the transparency data size of frame
             is set with this value.
-        
+
         :return: Transparency data size of frame (get) or None (set)
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].transparency_size = new_value
         else:
             return self.apngasm.get_frames()[frame].transparency_size
-    
-    def frame_delay_num(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+
+    def frame_delay_num(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the nominator of the duration of frame.
         Duration of time is delay_num / delay_den seconds.
-        
+
         :param int frame: Target frame number.
         :param Optional[int] new_value: If set, then the nominator of the duration of frame
             is set with this value.
-        
+
         :return: Nominator of the duration of frame.
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].delay_num = new_value
         else:
             return self.apngasm.get_frames()[frame].delay_num
-    
-    def frame_delay_den(self, frame: int, new_value: Optional[int] = None) -> Optional[int]:
-        '''
+
+    def frame_delay_den(
+        self, frame: int, new_value: Optional[int] = None
+    ) -> Optional[int]:
+        """
         Get/Set the denominator of the duration of frame.
         Duration of time is delay_num / delay_den seconds.
-        
+
         :param int frame: Target frame number.
         :param Optional[int] new_value: If set, then the denominator of the duration of frame
             is set with this value.
-        
+
         :return: Denominator of the duration of frame.
         :rtype: Optional[int]
-        '''
+        """
         if new_value:
             self.apngasm.get_frames()[frame].delay_den = new_value
         else:
             return self.apngasm.get_frames()[frame].delay_den
-    
-    def add_frame_from_file(self, file_path: str, delay_num: int = 100, delay_den: int = 1000) -> int:
-        '''
+
+    def add_frame_from_file(
+        self, file_path: str, delay_num: int = 100, delay_den: int = 1000
+    ) -> int:
+        """
         Adds a frame from a PNG file or frames from a APNG file to the frame vector.
-        
+
         :param str file_path: The relative or absolute path to an image file.
         :param int delay_num: The delay numerator for this frame (defaults to 100).
         :param int delay_den: The delay denominator for this frame (defaults to 1000).
-        
+
         :return: The new number of frames.
         :rtype: int
-        '''
+        """
         return self.apngasm.add_frame_from_file(
-            file_path=file_path,
-            delay_num=delay_num,
-            delay_den=delay_den
+            file_path=file_path, delay_num=delay_num, delay_den=delay_den
         )
-    
-    def add_frame_from_pillow(self, pillow_image: Image.Image, delay_num: int = 100, delay_den: int = 1000) -> int:
-        '''
-        Add a frame from Pillow image.
-        The frame duration is equal to delay_num / delay_den seconds.
-        Default frame duration is 100/1000 second, or 0.1 second.
-        
-        :param PIL.Image.Image pillow_image: Pillow image object.
-        :param int delay_num: The delay numerator for this frame (defaults to 100).
-        :param int delay_den: The delay denominator for this frame (defaults to 1000).
-        
-        :return: The new number of frames.
-        :rtype: int
-        '''
-        if pillow_image.mode not in ('RGB', 'RGBA'):
-            pillow_image = pillow_image.convert('RGBA')
-        return self.add_frame_from_numpy(
-            numpy_data=np.array(pillow_image),
-            width=pillow_image.width,
-            height=pillow_image.height,
-            mode=pillow_image.mode,
-            delay_num=delay_num,
-            delay_den=delay_den
-        )
-    
-    def add_frame_from_numpy(self, numpy_data: numpy.typing.NDArray, width: Optional[int] = None, height: Optional[int] = None, trns_color: Optional[numpy.typing.NDArray] = None, 
-                             mode: Optional[str] = None, delay_num: int = 100, delay_den: int = 1000) -> int:
-        '''
-        Add frame from numpy array.
-        The frame duration is equal to delay_num / delay_den seconds.
-        Default frame duration is 100/1000 second, or 0.1 second.
-        
-        :param numpy.typing.NDArray numpy_data: The pixel data, expressed as 3D numpy array.
-        :param Optional[int] width: The width of the pixel data. If not given, the 2nd dimension size of numpy_data is used.
-        :param Optional[int] height: The height of the pixel data. If not given, the 1st dimension size of numpy_data is used.
-        :param Optional[str] mode: The color mode of data. Possible values are RGB or RGBA. If not given, it is determined using the 3rd dimension size of numpy_data.
-        :param Optional[numpy.typing.NDArray] trns_color: The color [r, g, b] to be treated as transparent, expressed as 1D numpy array.
-            Only use if RGB mode.
-        :param int delay_num: The delay numerator for this frame (defaults to 100).
-        :param int delay_den: The delay denominator for this frame (defaults to 1000).
-        
-        :return: The new number of frames.
-        :rtype: int
-        '''
-        width = width if width else np.shape(numpy_data)[1]
-        height = height if height else np.shape(numpy_data)[0]
-
-        if not mode:
-            if np.shape(numpy_data)[2] == 3:
-                mode = 'RGB'
-            elif np.shape(numpy_data)[2] == 4:
-                mode = 'RGBA'
-            else:
-                raise TypeError('Cannot determine mode from numpy_data. '
-                                'expected 3rd dimension size to be 3 (RGB) or 4 (RGBA). '
-                                f'The given numpy_data 3rd dimension size was {np.shape(numpy_data)[2]}.')
-        
-        if mode == 'RGB':
-            if type(trns_color) == numpy.typing.NDArray:
-                frame = create_frame_from_rgb_trns(
+
+    if PILLOW_LOADED:
+
+        def add_frame_from_pillow(
+            self, pillow_image: Image.Image, delay_num: int = 100, delay_den: int = 1000
+        ) -> int:
+            """
+            Add a frame from Pillow image.
+            The frame duration is equal to delay_num / delay_den seconds.
+            Default frame duration is 100/1000 second, or 0.1 second.
+
+            :param PIL.Image.Image pillow_image: Pillow image object.
+            :param int delay_num: The delay numerator for this frame (defaults to 100).
+            :param int delay_den: The delay denominator for this frame (defaults to 1000).
+
+            :return: The new number of frames.
+            :rtype: int
+            """
+            if pillow_image.mode not in ("RGB", "RGBA"):
+                pillow_image = pillow_image.convert("RGBA")
+            return self.add_frame_from_numpy(
+                numpy_data=numpy.array(pillow_image),
+                width=pillow_image.width,
+                height=pillow_image.height,
+                mode=pillow_image.mode,
+                delay_num=delay_num,
+                delay_den=delay_den,
+            )
+
+    if NUMPY_LOADED:
+
+        def add_frame_from_numpy(
+            self,
+            numpy_data: numpy.typing.NDArray,
+            width: Optional[int] = None,
+            height: Optional[int] = None,
+            trns_color: Optional[numpy.typing.NDArray] = None,
+            mode: Optional[str] = None,
+            delay_num: int = 100,
+            delay_den: int = 1000,
+        ) -> int:
+            """
+            Add frame from numpy array.
+            The frame duration is equal to delay_num / delay_den seconds.
+            Default frame duration is 100/1000 second, or 0.1 second.
+
+            :param numpy.typing.NDArray numpy_data: The pixel data, expressed as 3D numpy array.
+            :param Optional[int] width: The width of the pixel data.
+                If not given, the 2nd dimension size of numpy_data is used.
+            :param Optional[int] height: The height of the pixel data.
+                If not given, the 1st dimension size of numpy_data is used.
+            :param Optional[str] mode: The color mode of data. Possible values are RGB or RGBA.
+                If not given, it is determined using the 3rd dimension size of numpy_data.
+            :param Optional[numpy.typing.NDArray] trns_color: The color [r, g, b] to be treated as transparent, expressed as 1D numpy array.
+                Only use if RGB mode.
+            :param int delay_num: The delay numerator for this frame (defaults to 100).
+            :param int delay_den: The delay denominator for this frame (defaults to 1000).
+
+            :return: The new number of frames.
+            :rtype: int
+            """
+            width = width if width else numpy.shape(numpy_data)[1]
+            height = height if height else numpy.shape(numpy_data)[0]
+
+            if not mode:
+                if numpy.shape(numpy_data)[2] == 3:
+                    mode = "RGB"
+                elif numpy.shape(numpy_data)[2] == 4:
+                    mode = "RGBA"
+                else:
+                    raise TypeError(
+                        "Cannot determine mode from numpy_data. "
+                        "expected 3rd dimension size to be 3 (RGB) or 4 (RGBA). "
+                        f"The given numpy_data 3rd dimension size was {numpy.shape(numpy_data)[2]}."
+                    )
+
+            if mode == "RGB":
+                if type(trns_color) == numpy.typing.NDArray:
+                    frame = create_frame_from_rgb_trns(
+                        pixels=numpy_data,
+                        width=width,
+                        height=height,
+                        trns_color=trns_color,
+                        delay_num=delay_num,
+                        delay_den=delay_den,
+                    )
+                else:
+                    frame = create_frame_from_rgb(
+                        pixels=numpy_data,
+                        width=width,
+                        height=height,
+                        delay_num=delay_num,
+                        delay_den=delay_den,
+                    )
+            elif mode == "RGBA":
+                if type(trns_color) == numpy.typing.NDArray:
+                    raise TypeError(
+                        "Cannot set trns_color on RGBA mode Pillow object. Must be RGB."
+                    )
+                frame = create_frame_from_rgba(
                     pixels=numpy_data,
                     width=width,
                     height=height,
-                    trns_color=trns_color,
                     delay_num=delay_num,
-                    delay_den=delay_den
+                    delay_den=delay_den,
                 )
             else:
-                frame = create_frame_from_rgb(
-                    pixels=numpy_data,
-                    width=width,
-                    height=height,
-                    delay_num=delay_num,
-                    delay_den=delay_den
-                )
-        elif mode == 'RGBA':
-            if type(trns_color) == numpy.typing.NDArray:
-                raise TypeError('Cannot set trns_color on RGBA mode Pillow object. Must be RGB.')
-            frame = create_frame_from_rgba(
-                pixels=numpy_data,
-                width=width,
-                height=height,
-                delay_num=delay_num,
-                delay_den=delay_den
-            )
-        else:
-            raise TypeError(f'Invalid mode: {mode}. Must be RGB or RGBA.')
+                raise TypeError(f"Invalid mode: {mode}. Must be RGB or RGBA.")
 
-        return self.apngasm.add_frame(frame)
+            return self.apngasm.add_frame(frame)
 
     def assemble(self, output_path: str) -> bool:
-        '''
+        """
         Assembles and outputs an APNG file.
-        
+
         :param str output_path: The output file path.
-        
+
         :return: true if assemble completed succesfully.
         :rtype: bool
-        '''
+        """
         return self.apngasm.assemble(output_path)
-    
+
     def disassemble_as_numpy(self, file_path: str) -> list[APNGFrame]:
-        '''
+        """
         Disassembles an APNG file to a list of frames, expressed as 3D numpy array.
-        
+
         :param str file_path: The file path to the PNG image to be disassembled.
-        
+
         :return: A list containing the frames of the disassembled PNG.
         :rtype: list[apngasm_python._apngasm_python.APNGFrame]
-        '''
+        """
         return self.apngasm.disassemble(file_path)
 
     def disassemble_as_pillow(self, file_path: str) -> list[APNGFrame]:
-        '''
+        """
         Disassembles an APNG file to a list of frames, expressed as Pillow images.
-        
+
         :param str file_path: The file path to the PNG image to be disassembled.
-        
+
         :return: A list containing the frames of the disassembled PNG.
         :rtype: list[apngasm_python._apngasm_python.APNGFrame]
-        '''
+        """
         frames_numpy = self.apngasm.disassemble(file_path)
         frames_pillow = []
         for frame in frames_numpy:
             mode = self.color_type_dict[frame.color_type]
-            frame_pillow = Image.frombytes(mode, (frame.width, frame.height), frame.pixels)
+            frame_pillow = Image.frombytes(
+                mode, (frame.width, frame.height), frame.pixels
+            )
             frames_pillow.append(frame_pillow)
-        
+
         return frames_pillow
-    
+
     def save_pngs(self, output_dir: str) -> bool:
-        '''
+        """
         Saves individual PNG files of the frames in the frame vector.
-        
+
         :param str output_dir: The directory where the PNG fils will be saved.
-        
+
         :return: true if all files were saved successfully.
         :rtype: bool
-        '''
+        """
         return self.apngasm.save_pngs(output_dir)
-    
+
     def load_animation_spec(self, file_path: str) -> list[APNGFrame]:
-        '''
+        """
         Loads an animation spec from JSON or XML.
         Loaded frames are added to the end of the frame vector.
         For more details on animation specs see:
@@ -388,116 +460,115 @@ def load_animation_spec(self, file_path: str) -> list[APNGFrame]:
 
         :return: A vector containing the loaded frames.
         :rtype: list[apngasm_python._apngasm_python.APNGFrame]
-        '''
+        """
         return self.apngasm.load_animation_spec(file_path)
-    
+
     def save_json(self, output_path: str, image_dir: str) -> bool:
-        '''
+        """
         Saves a JSON animation spec file.
         You probably won't need to use this function
-        
+
         :param str output_path: Path to save the file to.
         :param str image_dir: Directory where frame files are to be saved
             if not the same path as the animation spec.
-        
+
         :return: true if save was successful.
         :rtype: bool
-        '''
+        """
         return self.apngasm.save_json(output_path, image_dir)
-    
+
     def save_xml(self, output_path: str, image_dir: str) -> bool:
-        '''
+        """
         Saves an XML animation spec file.
-        
+
         :param str filePath: Path to save the file to.
         :param str image_dir: Directory where frame files are to be saved
             if not the same path as the animation spec.
 
         :return: true if save was successful.
         :rtype: bool
-        '''
+        """
         return self.apngasm.save_xml(output_path, image_dir)
 
     def set_apng_asm_listener(self, listener: Optional[IAPNGAsmListener] = None):
-        '''
+        """
         Sets a listener.
         You probably won't need to use this function.
-        
+
         :param Optional[apngasm_python._apngasm_python.IAPNGAsmListener] listener: A pointer to the listener object.
             If the argument is None,
             a default APNGAsmListener will be created and assigned.
-        '''
+        """
         return self.apngasm.set_apng_asm_listener(listener)
 
     def set_loops(self, loops: int = 0):
-        '''
+        """
         Set loop count of animation.
-        
+
         :param int loops: Loop count of animation. If the argument is 0 a loop count is infinity.
-        '''
+        """
         return self.apngasm.set_loops(loops)
-    
+
     def set_skip_first(self, skip_first: int):
-        '''
+        """
         Set flag of skip first frame.
 
         :param int skip_first: Flag of skip first frame.
-        '''
+        """
         return self.apngasm.set_skip_first(skip_first)
 
     def get_frames(self) -> list[APNGFrame]:
-        '''
+        """
         Returns the frame vector.
 
         :return: frame vector.
         :rtype: list[apngasm_python._apngasm_python.APNGFrame]
-        '''
+        """
         return self.apngasm.get_frames()
-    
+
     def get_loops(self) -> int:
-        '''
+        """
         Returns the loop count.
 
         :return: loop count.
         :rtype: int
-        '''
+        """
         return self.apngasm.get_loops()
-    
+
     def is_skip_first(self) -> int:
-        '''
+        """
         Returns the flag of skip first frame.
 
         :return: flag of skip first frame.
         :rtype: int
-        '''
+        """
         return self.apngasm.get_loops()
 
     def frame_count(self) -> int:
-        '''
+        """
         Returns the number of frames.
 
         :return: number of frames.
         :rtype: int
-        '''
+        """
         return self.apngasm.frame_count()
-    
+
     def reset(self) -> int:
-        '''
+        """
         Destroy all frames in memory/dispose of the frame vector.
         Leaves the apngasm object in a clean state.
         Returns number of frames disposed of.
 
         :return: number of frames disposed of.
         :rtype: int
-        '''
+        """
         return self.apngasm.reset()
 
     def version(self) -> str:
-        '''
+        """
         Returns the version of APNGAsm.
 
         :return: version of APNGAsm.
         :rtype: str
-        '''
+        """
         return self.apngasm.version()
-
diff --git a/src-python/apngasm_python/apngasm.pyi b/src-python/apngasm_python/apngasm.pyi
index 1b4b580..89b08a5 100644
--- a/src-python/apngasm_python/apngasm.pyi
+++ b/src-python/apngasm_python/apngasm.pyi
@@ -4,6 +4,9 @@ from PIL import Image
 from _typeshed import Incomplete
 from typing import Optional
 
+NUMPY_LOADED: bool
+PILLOW_LOADED: bool
+
 class APNGAsmBinder:
     color_type_dict: Incomplete
     apngasm: Incomplete