Add CTC training

.flake8

@@ -0,0 +1,8 @@
+[flake8]
+show-source=true
+statistics=true
+max-line-length = 80
+
+exclude =
+  .git,
+  **/data/**

.github/workflows/style_check.yml

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+# Copyright      2021  Fangjun Kuang (csukuangfj@gmail.com)
+
+# See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: style_check
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  style_check:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-18.04, macos-10.15]
+        python-version: [3.7, 3.9]
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Setup Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v1
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install Python dependencies
+        run: |
+          python3 -m pip install --upgrade pip black flake8
+
+      - name: Run flake8
+        shell: bash
+        working-directory: ${{github.workspace}}
+        run: |
+          # stop the build if there are Python syntax errors or undefined names
+          flake8 . --count --show-source --statistics
+          flake8 .
+
+      - name: Run black
+        shell: bash
+        working-directory: ${{github.workspace}}
+        run: |
+          black --check --diff .

.github/workflows/test.yml

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+# Copyright      2021  Fangjun Kuang (csukuangfj@gmail.com)
+
+# See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: test
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-18.04, macos-10.15]
+        python-version: [3.6, 3.7, 3.8, 3.9]
+        torch: ["1.8.1"]
+        k2-version: ["1.2.dev20210724"]
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Setup Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v1
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install Python dependencies
+        run: |
+          python3 -m pip install --upgrade pip pytest kaldialign
+          pip install k2==${{ matrix.k2-version }}+cpu.torch${{ matrix.torch }} -f https://k2-fsa.org/nightly/
+
+          # Don't use: pip install lhotse
+          # since it installs a version of PyTorch that is not predictable
+          git clone --depth 1 https://github.com/lhotse-speech/lhotse
+          cd lhotse
+          sed -i.bak "/torch/d" requirements.txt
+          pip install -r ./requirements.txt
+
+
+      - name: Run tests
+        if: startsWith(matrix.os, 'ubuntu')
+        run: |
+          ls -lh
+          export PYTHONPATH=$PWD:$PWD/lhotse:$PYTHONPATH
+          echo $PYTHONPATH
+          pytest ./test
+
+      - name: Run tests
+        if: startsWith(matrix.os, 'macos')
+        run: |
+          ls -lh
+          export PYTHONPATH=$PWD:$PWD/lhotse:$PYTHONPATH
+          lib_path=$(python -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")
+          echo "lib_path: $lib_path"
+          export DYLD_LIBRARY_PATH=$lib_path:$DYLD_LIBRARY_PATH
+          pytest ./test

.gitignore

@@ -0,0 +1,6 @@
+data
+__pycache__
+path.sh
+exp
+exp*/
+*.pt

.pre-commit-config.yaml

@@ -0,0 +1,26 @@
+repos:
+  - repo: https://github.com/psf/black
+    rev: 21.6b0
+    hooks:
+      - id: black
+        args: [--line-length=80]
+
+  - repo: https://github.com/PyCQA/flake8
+    rev: 3.9.2
+    hooks:
+      - id: flake8
+        args: [--max-line-length=80]
+
+  - repo: https://github.com/pycqa/isort
+    rev: 5.9.2
+    hooks:
+      - id: isort
+        args: [--profile=black, --line-length=80]
+
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.0.1
+    hooks:
+      - id: check-executables-have-shebangs
+      - id: end-of-file-fixer
+      - id: mixed-line-ending
+      - id: trailing-whitespace

LICENSE

@@ -0,0 +1,211 @@
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