Docs

Build modernization

.flake8

@@ -1,3 +0,0 @@
-[flake8]
-per-file-ignores = 
-  wavinfo/__init__.py: F401

.github/workflows/python-package.yml

@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
 
     steps:
     - uses: actions/checkout@v2.5.0
@@ -27,8 +27,8 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        python -m pip install pytest
+        python -m pip install --group dev
-        python -m pip install -e .
+        python -m pip install .
     - name: Setup FFmpeg
       uses: FedericoCarboni/setup-ffmpeg@v2
     - name: Test with pytest

.github/workflows/python-ruff.yml

@@ -1,7 +1,7 @@
 # This workflow will install Python dependencies, run tests and lint with a variety of Python versions
 # For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
 
-name: Flake8
+name: Lint with Ruff
 
 on:
   push:
@@ -11,12 +11,11 @@ on:
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.11"]
+        python-version: ["3.13", "3.14"]
 
     steps:
     - uses: actions/checkout@v2.5.0
@@ -27,14 +26,8 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        python -m pip install flake8
+        python -m pip install --group dev
-        python -m pip install -e .
+        python -m pip install .
-    - name: Lint with flake8
+    - name: Lint with ruff 
       run: |
-        # stop the build if there are Python syntax errors or undefined names
+        ruff check src
-        flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
-        # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
-        flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
-    - name: Lint with flake8
-      run: |
-        flake8 wavinfo

.github/workflows/pythonpublish.yml

@@ -8,29 +8,33 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v4.2.2
     - name: Set up Python
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v5.3.0
       with:
         python-version: '3.x'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install setuptools build wheel twine lxml
+    - name: Setup uv and Handle Its Cache
-    - name: Build and publish
+      # You may pin to the exact commit or the version.
-      env:
+      # uses: hynek/setup-cached-uv@757bedc3f972eb7227a1aa657651f15a8527c817
-        TWINE_USERNAME: __token__
+      uses: hynek/setup-cached-uv@v2.3.0          
-        TWINE_PASSWORD: ${{ secrets.PYPI_APIKEY }}
+    - name: Build 
       run: |
-        python -m build .
+        uv build --wheel
-        twine upload dist/*
+    - name: Publish to Pypi
-    - name: Report to Mastodon
+      uses: pypa/gh-action-pypi-publish@v1.13.0
-      uses: cbrgm/mastodon-github-action@v1.0.1
       with:
-        message: |
+        password: ${{ secrets.PYPI_APIKEY }}
-          I just released a new version of wavinfo, my library for reading WAVE file metadata!
+    # - name: Send Bluesky Post
-          #sounddesign #filmmaking #audio #python
+    #   uses: myConsciousness/bluesky-post@v5
-          ${{ github.server_url }}/${{ github.repository }}
+    #   with:
-      env:
+    #     text: |
-        MASTODON_URL: ${{ secrets.MASTODON_URL }}
+    #       I've released a new version of wavinfo, my module for 
-        MASTODON_ACCESS_TOKEN: ${{ secrets.MASTODON_ACCESS_TOKEN }}
+    #       reading WAVE metadata.
+    #     link-preview-url: ${{ github.server_url }}/${{ github.repository }}
+    #     identifier: ${{ secrets.BLUESKY_APP_USER }}  
+    #     password: ${{ secrets.BLUESKY_APP_PASSWORD }}
+    #     service: bsky.social    
+    #     retry-count: 1

.readthedocs.yaml

@@ -9,11 +9,11 @@ version: 2
 build:
   os: ubuntu-20.04
   tools:
-    python: "3.10"
+    python: "3.13"
-    # You can also specify other tool versions:
+  jobs:
-    # nodejs: "16"
+    install: 
-    # rust: "1.55"
+      - pip install --upgrade pip
-    # golang: "1.17"
+      - pip install --group 'doc'
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
@@ -28,5 +28,3 @@ python:
   install:
     - method: pip
       path: .
-      extra_requirements:
-        - doc

README.md

@@ -2,7 +2,7 @@
 ![GitHub last commit](https://img.shields.io/github/last-commit/iluvcapra/wavinfo) [![Documentation Status](https://readthedocs.org/projects/wavinfo/badge/?version=latest)](https://wavinfo.readthedocs.io/en/latest/?badge=latest) ![](https://img.shields.io/github/license/iluvcapra/wavinfo.svg)
 
 [![Tests](https://github.com/iluvcapra/wavinfo/actions/workflows/python-package.yml/badge.svg)](https://github.com/iluvcapra/wavinfo/actions/workflows/python-package.yml)
-[![Flake8](https://github.com/iluvcapra/wavinfo/actions/workflows/python-flake8.yml/badge.svg)](https://github.com/iluvcapra/wavinfo/actions/workflows/python-flake8.yml)
+[![Ruff](https://github.com/iluvcapra/wavinfo/actions/workflows/python-ruff.yml/badge.svg)](https://github.com/iluvcapra/wavinfo/actions/workflows/python-ruff.yml)
 [![codecov](https://codecov.io/gh/iluvcapra/wavinfo/branch/master/graph/badge.svg?token=9DZQfZENYv)](https://codecov.io/gh/iluvcapra/wavinfo)
 
 # wavinfo
@@ -31,6 +31,7 @@ it is not supported, please submit an issue!
   and Dolby Atmos `dbmd` metadata for re-renders and mixdowns.
 * Wave embedded [cue markers][cues], cue marker labels, notes and timed ranges as used
   by Zoom, iZotope RX, etc.
+* Wave embedded [sampler][smpl] and sample loop metadata.
 * The [wav format][format] is also parsed, so you can access the basic sample rate 
   and channel count information.
 
@@ -38,6 +39,7 @@ it is not supported, please submit an issue!
 [format]:https://wavinfo.readthedocs.io/en/latest/classes.html#wavinfo.wave_reader.WavAudioFormat
 [cues]:https://wavinfo.readthedocs.io/en/latest/scopes/cue.html
 [bext]:https://wavinfo.readthedocs.io/en/latest/scopes/bext.html
+[smpl]:https://wavinfo.readthedocs.io/en/latest/scopes/smpl.html
 [smpte_330m2011]:https://wavinfo.readthedocs.io/en/latest/scopes/bext.html#wavinfo.wave_bext_reader.WavBextReader.umid
 [adm]:https://wavinfo.readthedocs.io/en/latest/scopes/adm.html
 [ebu3285s6]:https://wavinfo.readthedocs.io/en/latest/scopes/dolby.html

docs/source/command_line.rst

@@ -6,89 +6,135 @@ from the command line and output metadata to stdout.
 
 .. code-block:: shell
 
-    $ wavinfo [--ixml | --adm] INFILE +
+    $ wavinfo [[-i] | [--ixml | --adm]] INFILE +
-
-By default, `wavinfo` will output a JSON dictionary for each file argument.
 
 
 Options
 -------
 
-Two option flags will change the behavior of the command:
+By default, `wavinfo` will output a JSON dictionary for each file argument.
+
+``-i`` 
+    `wavinfo` will run in `interactive mode`_.
+
+Two option flags will change the behavior of the command in non-interactive 
+mode:
 
 ``--ixml``
-    The *\-\-ixml* flag will cause `wavinfo` to output the iXML metadata payload
+    The *\-\-ixml* flag will cause `wavinfo` to output the iXML metadata
-    of each input wave file, or will emit an error message to stderr if iXML 
+    payload of each input wave file, or will emit an error message to stderr if
-    metadata is not present.
+    iXML metadata is not present.
 
 ``--adm``
     The *\-\-adm* flag will cause `wavinfo` to output the ADM XML metadata 
     payload of each input wave file, or will emit an error message to stderr if
     ADM XML metadata is not present.
 
-These options are mutually-exclusive, with `\-\-adm` taking precedence. 
+These options are mutually-exclusive, with `\-\-adm` taking precedence. The 
+``--ixml`` and ``--adm`` flags futher take precedence over ``-i``.
+
+
+Interactive Mode 
+-----------------
+
+In interactive mode, `wavinfo` will present a command prompt which allows you
+to query the files provided on the command line and explore the metadata tree 
+interactively. Each file on the command line is scanned and presented as a 
+tree of metadata records.
+
+Commands include:
+
+``ls``
+    List the available metadata keys at the current level.
+
+``cd``
+    Traverse to a metadata key in the current level (or enter `..` to go up 
+    to the prevvious level).
+
+``bye``
+    Exit to the shell.
+
+Type `help` or `?` at the prompt to get a full list of commands.
 
 
 Example Output
 --------------
 
+.. attention::
+
+   Metadata fields containing binary data, such as the Broadcast-WAV UMID, will 
+   be included in the JSON output as a base-64 encoded string, preceded by the
+   marker "base64:".
+
 .. code-block:: javascript
 
   {
-    "filename": "tests/test_files/sounddevices/A101_1.WAV",
+  "filename": "../tests/test_files/nuendo/wavinfo Test Project - Audio - 1OA.wav",
-    "run_date": "2022-11-26T17:56:38.342935",
+  "run_date": "2024-11-25T10:26:11.280053",
-    "application": "wavinfo 2.1.0",
+  "application": "wavinfo 3.0.0",
   "scopes": {
     "fmt": {
-        "audio_format": 1,
+      "audio_format": 65534,
-        "channel_count": 2,
+      "channel_count": 4,
       "sample_rate": 48000,
-        "byte_rate": 288000,
+      "byte_rate": 576000,
-        "block_align": 6,
+      "block_align": 12,
       "bits_per_sample": 24
     },
     "data": {
-        "byte_count": 1441434,
+      "byte_count": 576000,
-        "frame_count": 240239
+      "frame_count": 48000
     },
     "ixml": {
       "track_list": [
         {
           "channel_index": "1",
           "interleave_index": "1",
-            "name": "MKH516 A",
+          "name": "",
-            "function": ""
+          "function": "ACN0-FOA"
         },
         {
           "channel_index": "2",
           "interleave_index": "2",
-            "name": "Boom",
+          "name": "",
-            "function": ""
+          "function": "ACN1-FOA"
+        },
+        {
+          "channel_index": "3",
+          "interleave_index": "3",
+          "name": "",
+          "function": "ACN2-FOA"
+        },
+        {
+          "channel_index": "4",
+          "interleave_index": "4",
+          "name": "",
+          "function": "ACN3-FOA"
         }
       ],
-        "project": "BMH",
+      "project": "wavinfo Test Project",
-        "scene": "A101",
+      "scene": null,
-        "take": "1",
+      "take": null,
-        "tape": "18Y12M31",
+      "tape": null,
-        "family_uid": "USSDVGR1112089007124001008206300",
+      "family_uid": "E5DDE719B9484A758162FF7B652383A3",
       "family_name": null
     },
     "bext": {
-        "description": "sSPEED=023.976-ND\r\nsTAKE=1\r\nsUBITS=$12311801\r\nsSWVER=2.67\r\nsPROJECT=BMH\r\nsSCENE=A101\r\nsFILENAME=A101_1.WAV\r\nsTAPE=18Y12M31\r\nsTRK1=MKH516 A\r\nsTRK2=Boom\r\nsNOTE=\r\n",
+      "description": "wavinfo Test Project Nuendo output",
-        "originator": "Sound Dev: 702T S#GR1112089007",
+      "originator": "Nuendo",
-        "originator_ref": "USSDVGR1112089007124001008206301",
+      "originator_ref": "USJPHNNNNNNNNN202829RRRRRRRRR",
-        "originator_date": "2018-12-31",
+      "originator_date": "2022-12-02",
-        "originator_time": "12:40:00",
+      "originator_time": "10:21:06",
-        "time_reference": 2190940753,
+      "time_reference": 172800000,
-        "version": 1,
+      "version": 2,
-        "umid": "0000000000000000000000000000000000000000000000000000000000000000",
+      "umid": "base64:k/zr4qE4RiaXyd/fO7GuCwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA==",
-        "coding_history": "A=PCM,F=48000,W=24,M=stereo,R=48000,T=2 Ch\r\n",
+      "coding_history": "A=PCM,F=48000,W=24,T=Nuendo\r\n",
-        "loudness_value": null,
+      "loudness_value": 327.67,
-        "loudness_range": null,
+      "loudness_range": 327.67,
-        "max_true_peak": null,
+      "max_true_peak": 327.67,
-        "max_momentary_loudness": null,
+      "max_momentary_loudness": 327.67,
-        "max_shortterm_loudness": null
+      "max_shortterm_loudness": 327.67
-        }
     }
   }
+}
 

docs/source/conf.py

@@ -12,24 +12,24 @@
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 #
+# import importlib
 import os
 import sys
-sys.path.insert(0, os.path.abspath('../..'))
+sys.path.insert(0, os.path.abspath('../../src'))
-sys.path.insert(0, os.path.abspath("../../.."))
+sys.path.insert(0, os.path.abspath("../../../src"))
 print(sys.path)
 
-import wavinfo
-
 # -- Project information -----------------------------------------------------
 
 project = u'wavinfo'
-copyright = u'2018-2023, Jamie Hardt'
+copyright = u'2018-2025, Jamie Hardt'
 author = u'Jamie Hardt'
 
 # The short X.Y version
-version = wavinfo.__short_version__
+version = "4.0"
 # The full version, including alpha/beta/rc tags
-release = wavinfo.__version__
+release = "4.0.0"
+# release = importlib.metadata.version("wavinfo")
 
 
 # -- General configuration ---------------------------------------------------

docs/source/references.rst

@@ -39,7 +39,7 @@ iXML
 Sampler Metadata
 ----------------
 
-* `RecordingBlogs.com — Sample chunk (of a Wave file)<https://www.recordingblogs.com/wiki/sample-chunk-of-a-wave-file>`_
+* `RecordingBlogs.com — Sample chunk (of a Wave file) <https://www.recordingblogs.com/wiki/sample-chunk-of-a-wave-file>`_
 
 RIFF Metadata
 -------------

docs/source/scopes/smpl.rst

@@ -0,0 +1,14 @@
+
+Sampler Metadata
+=================
+
+Class Reference
+---------------
+
+.. automodule:: wavinfo.wave_smpl_reader
+
+.. autoclass:: wavinfo.wave_smpl_reader.WavSmplReader
+    :members:
+
+.. autoclass:: wavinfo.wave_smpl_reader.WaveSmplLoop
+    :members:

pyproject.toml

@@ -1,27 +1,26 @@
-# https://python-poetry.org/docs/pyproject/
-
 [build-system]
-requires = ["poetry-core"]
+requires = ["uv_build>=0.8.18,<0.9.0"]
-build-backend = "poetry.core.masonry.api"
+build-backend = "uv_build"
 
-[tool.poetry]
+[project]
 name = "wavinfo"
-version = "3.0.1"
+version = "4.0.0"
 description = "Probe WAVE files for all metadata"
-authors = ["Jamie Hardt <jamiehardt@me.com>"]
+authors = [{ name = "Jamie Hardt", email = "jamiehardt@me.com"}]
 license = "MIT" 
 readme = "README.md"
+requires-python = ">=3.8"
 classifiers = [
     'Development Status :: 5 - Production/Stable',
     'License :: OSI Approved :: MIT License',
     'Topic :: Multimedia',
     'Topic :: Multimedia :: Sound/Audio',
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
-    "Programming Language :: Python :: 3.13"
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14"
 ]
 homepage = "https://github.com/iluvcapra/wavinfo"
 repository = "https://github.com/iluvcapra/wavinfo.git"
@@ -39,17 +38,22 @@ keywords = [
     'broadcast' 
 ]
 
-[tool.poetry.extras]
+dependencies = [
-doc = ['sphinx', 'sphinx_rtd_theme']
+    "lxml>=6.0.2",
+]
 
-[tool.poetry.scripts]
+[dependency-groups]
-wavinfo = 'wavinfo.__main__:main'
+dev = [
+    "pytest>=8.3.5",
+    "ruff>=0.14.0",
+]
+doc = [
+    "sphinx>=7.1.2",
+    "sphinx-rtd-theme>=3.0.2",
+]
 
-[tool.poetry.dependencies]
+[project.scripts]
-python = "^3.8"
+wavinfo = "wavinfo:__main__.main"
-lxml = "~= 5.3.0"
-sphinx_rtd_theme = {version= '>= 1.1.1', optional=true}
-sphinx = {version= '>= 5.3.0', optional=true}
 
 [tool.pyright]
 typeCheckingMode = "basic"
@@ -65,3 +69,4 @@ disable = [
     "R0913", # (too-many-arguments)
     "W0105", # (pointless-string-statement)
 ]
+

src/wavinfo/__init__.py

@@ -2,5 +2,8 @@
 Probe WAVE Files for iXML, Broadcast-WAVE and other metadata.
 """
 
+__all__ = ['WavInfoReader', 'WavInfoEOFError']
+
 from .wave_reader import WavInfoReader
 from .riff_parser import WavInfoEOFError
+

src/wavinfo/__main__.py

@@ -8,6 +8,9 @@ import json
 from enum import Enum
 import importlib.metadata
 from base64 import b64encode
+from cmd import Cmd
+from shlex import split
+from typing import List, Dict, Union
 
 
 class MyJSONEncoder(json.JSONEncoder):
@@ -15,7 +18,7 @@ class MyJSONEncoder(json.JSONEncoder):
         if isinstance(o, Enum):
             return o._name_
         elif isinstance(o, bytes):
-            return b64encode(o).decode('ascii')
+            return 'base64:' + b64encode(o).decode('ascii')
         else:
             return super().default(o)
 
@@ -24,6 +27,85 @@ class MissingDataError(RuntimeError):
     pass
 
 
+class MetaBrowser(Cmd):
+    prompt = "(wavinfo) "
+
+    metadata: Union[List, Dict]
+    path: List[str] = []
+
+    @property
+    def cwd(self):
+        root: List | Dict = self.metadata
+        for key in self.path:
+            if isinstance(root, list):
+                root = root[int(key)]
+            else:
+                root = root[key]
+
+        return root
+
+    @staticmethod
+    def print_value(collection, key):
+        val = collection[key]
+        if isinstance(val, int):
+            print(f" - {key}: {val}")
+        elif isinstance(val, str):
+            print(f" - {key}: \"{val}\"")
+        elif isinstance(val, dict):
+            print(f" - {key}: Dict ({len(val)} keys)")
+        elif isinstance(val, list):
+            print(f" - {key}: List ({len(val)} keys)")
+        elif isinstance(val, bytes):
+            print(f" - {key}: ({len(val)} bytes)")
+        elif val is None:
+            print(f" - {key}: (NO VALUE)")
+        else:
+            print(f" - {key}: Unknown")
+
+    def do_ls(self, _):
+        'List items at the current node: LS'
+        root = self.cwd
+
+        if isinstance(root, list):
+            print("List:")
+            for i in range(len(root)):
+                self.print_value(root, i)
+
+        elif isinstance(root, dict):
+            print("Dictionary:")
+            for key in root:
+                self.print_value(root, key)
+
+        else:
+            print("Cannot print node, is not a list or dictionary.")
+
+    def do_cd(self, args):
+        'Switch to a different node: CD node-name | ".."'
+        argv = split(args)
+        if argv[0] == "..":
+            self.path = self.path[0:-1]
+        else:
+            if isinstance(self.cwd, list):
+                if int(argv[0]) < len(self.cwd):
+                    self.path = self.path + [argv[0]]
+                else:
+                    print(f"Index {argv[0]} does not exist")
+            elif isinstance(self.cwd, dict):
+                if argv[0] in self.cwd.keys():
+                    self.path = self.path + [argv[0]]
+                else:
+                    print(f"Key \"{argv[0]}\" does not exist")
+
+        if len(self.path) > 0:
+            self.prompt = "(" + "/".join(self.path) + ") "
+        else:
+            self.prompt = "(wavinfo) "
+
+    def do_bye(self, _):
+        'Exit the interactive browser: BYE'
+        return True
+
+
 def main():
     version = importlib.metadata.version('wavinfo')
     manpath = os.path.dirname(__file__) + "/man"
@@ -51,8 +133,15 @@ def main():
                       default=False,
                       action='store_true')
 
+    parser.add_option('-i',
+                      help='Read metadata with an interactive prompt',
+                      default=False,
+                      action='store_true')
+
     (options, args) = parser.parse_args(sys.argv)
 
+    interactive_dict = []
+
     # if options.install_manpages:
     #     print("Installing manpages...")
     #     print(f"Docfiles at {__file__}")
@@ -98,7 +187,12 @@ def main():
 
                     ret_dict['scopes'][scope][name] = value
 
-                json.dump(ret_dict, cls=MyJSONEncoder, fp=sys.stdout, indent=2)
+                if options.i:
+                    interactive_dict.append(ret_dict)
+                else:
+                    json.dump(ret_dict, cls=MyJSONEncoder, fp=sys.stdout,
+                              indent=2)
+
         except MissingDataError as e:
             print("MissingDataError: Missing metadata (%s) in file %s" %
                   (e, arg), file=sys.stderr)
@@ -106,6 +200,11 @@ def main():
         except Exception as e:
             raise e
 
+        if len(interactive_dict) > 0:
+            cli = MetaBrowser()
+            cli.metadata = interactive_dict
+            cli.cmdloop()
+
 
 if __name__ == "__main__":
     main()

src/wavinfo/man/man1/wavinfo.1

@@ -3,6 +3,7 @@
 wavinfo \- probe wave files for metadata
 .SH SYNOPSIS
 .SY wavinfo
+.I "[\-i]"
 .I "[\-\-adm]"
 .I "[\-\-ixml]"
 .I FILE ...
@@ -24,6 +25,10 @@ Output any iXML metdata in
 .BR FILE .
 .IP "\-h, \-\-help"
 Print brief help.
+.IP "\-i"
+Enter 
+.I "interactive mode"
+and browse metadata in FILE with an interactive command prompt.
 .SH DETAILED DESCRIPTION
 .B wavinfo 
 collects metadata according to different 

src/wavinfo/wave_bext_reader.py

@@ -89,7 +89,7 @@ class WavBextReader:
         #     umid_str = umid_parsed.basic_umid_to_str()
         # else:
 
-        umid_str = None
+        # umid_str = None
 
         return {'description': self.description,
                 'originator': self.originator,
@@ -98,7 +98,7 @@ class WavBextReader:
                 'originator_time': self.originator_time,
                 'time_reference': self.time_reference,
                 'version': self.version,
-                'umid': umid_str,
+                'umid': self.umid,
                 'coding_history': self.coding_history,
                 'loudness_value': self.loudness_value,
                 'loudness_range': self.loudness_range,

src/wavinfo/wave_smpl_reader.py

@@ -8,7 +8,7 @@ class WaveSmplLoop(NamedTuple):
     loop_type: int
     start: int
     end: int
-    fraction: int
+    detune_cents: int
     repetition_count: int
 
     def loop_type_desc(self):
@@ -30,7 +30,7 @@ class WaveSmplLoop(NamedTuple):
             'loop_type_description': self.loop_type_desc(),
             'start_samples': self.start,
             'end_samples': self.end,
-            'fraction': self.fraction,
+            'detune_cents': self.detune_cents,
             'repetition_count': self.repetition_count,
         }
 
@@ -42,8 +42,8 @@ class WavSmplReader:
         Read sampler metadata from smpl chunk.
         """
 
-        header_field_fmt = "<IIIIIIbbbbII"
+        header_field_fmt = "<IIIIiIbbbbII"
-        loop_field_fmt = "<IIIIII"
+        loop_field_fmt = "<IIIIiI"
         header_size = struct.calcsize(header_field_fmt)
         loop_size = struct.calcsize(loop_field_fmt)
 
@@ -65,7 +65,7 @@ class WavSmplReader:
         self.midi_note: int = unpacked_data[3]
 
         #: The number of semitones above the MIDI note the loops tune for.
-        self.midi_pitch_fraction_semis: int = unpacked_data[4]
+        self.midi_pitch_detune_cents: int = unpacked_data[4]
 
         #: SMPTE timecode format, one of (0, 24, 25, 29, 30)
         self.smpte_format: int = unpacked_data[5]
@@ -89,11 +89,14 @@ class WavSmplReader:
                 loop_type=unpacked_loop[1],
                 start=unpacked_loop[2],
                 end=unpacked_loop[3],
-                fraction=unpacked_loop[4],
+                detune_cents=unpacked_loop[4],
                 repetition_count=unpacked_loop[5]))
 
         #: Sampler-specific user data.
-        self.sampler_udata: bytes = smpl_data[
+        self.sampler_udata: bytes | None = None
+
+        if sampler_udata_length > 0:
+            self.sampler_udata = smpl_data[
                 header_size + loop_size * loop_count:
                 header_size + loop_size * loop_count + sampler_udata_length]
 
@@ -103,7 +106,7 @@ class WavSmplReader:
             'product': self.product,
             'sample_period_ns': self.sample_period_ns,
             'midi_note': self.midi_note,
-            'midi_pitch_fraction_semis': self.midi_pitch_fraction_semis,
+            'midi_pitch_detune_cents': self.midi_pitch_detune_cents,
             'smpte_format': self.smpte_format,
             'smpte_offset': "%02i:%02i:%02i:%02i" % self.smpte_offset,
             'loops': [x.to_dict() for x in self.sample_loops],