Add SPHERE support to "sox_io" backend

test/torchaudio_unittest/sox_io_backend/info_test.py

@@ -108,6 +108,20 @@ def test_vorbis(self, sample_rate, num_channels, quality_level):
         assert info.num_frames == sample_rate * duration
         assert info.num_channels == num_channels
 
+    @parameterized.expand(list(itertools.product(
+        [8000, 16000],
+        [1, 2],
+    )), name_func=name_func)
+    def test_sphere(self, sample_rate, num_channels):
+        """`sox_io_backend.info` can check sph file correctly"""
+        duration = 1
+        path = self.get_temp_path('data.sph')
+        sox_utils.gen_audio_file(path, sample_rate, num_channels, duration=duration)
+        info = sox_io_backend.info(path)
+        assert info.sample_rate == sample_rate
+        assert info.num_frames == sample_rate * duration
+        assert info.num_channels == num_channels
+
 
 @skipIfNoExtension
 class TestInfoOpus(PytorchTestCase):

test/torchaudio_unittest/sox_io_backend/load_test.py

@@ -120,6 +120,28 @@ def assert_vorbis(self, sample_rate, num_channels, quality_level, duration):
         assert sr == sample_rate
         self.assertEqual(data, data_ref, atol=4e-05, rtol=1.3e-06)
 
+    def assert_sphere(self, sample_rate, num_channels, duration):
+        """`sox_io_backend.load` can load sph format.
+
+        This test takes the same strategy as mp3 to compare the result
+        """
+        path = self.get_temp_path('1.original.sph')
+        ref_path = self.get_temp_path('2.reference.wav')
+
+        # 1. Generate sph with sox
+        sox_utils.gen_audio_file(
+            path, sample_rate, num_channels,
+            bit_depth=32, duration=duration)
+        # 2. Convert to wav with sox
+        sox_utils.convert_audio_file(path, ref_path)
+        # 3. Load sph with torchaudio
+        data, sr = sox_io_backend.load(path)
+        # 4. Load wav with scipy
+        data_ref = load_wav(ref_path)[0]
+        # 5. Compare
+        assert sr == sample_rate
+        self.assertEqual(data, data_ref, atol=4e-05, rtol=1.3e-06)
+
 
 @skipIfNoExec('sox')
 @skipIfNoExtension
@@ -230,6 +252,14 @@ def test_opus(self, bitrate, num_channels, compression_level):
         assert sample_rate == sr
         self.assertEqual(expected, found)
 
+    @parameterized.expand(list(itertools.product(
+        [8000, 16000],
+        [1, 2],
+    )), name_func=name_func)
+    def test_sphere(self, sample_rate, num_channels):
+        """`sox_io_backend.load` can load sph format correctly."""
+        self.assert_sphere(sample_rate, num_channels, duration=1)
+
 
 @skipIfNoExec('sox')
 @skipIfNoExtension

test/torchaudio_unittest/sox_io_backend/save_test.py

@@ -168,6 +168,38 @@ def assert_vorbis(self, *args, **kwargs):
         else:
             raise error
 
+    def assert_sphere(self, sample_rate, num_channels, duration):
+        """`sox_io_backend.save` can save sph format.
+
+        This test takes the same strategy as mp3 to compare the result
+        """
+        src_path = self.get_temp_path('1.reference.wav')
+        flc_path = self.get_temp_path('2.1.torchaudio.sph')
+        wav_path = self.get_temp_path('2.2.torchaudio.wav')
+        flc_path_sox = self.get_temp_path('3.1.sox.sph')
+        wav_path_sox = self.get_temp_path('3.2.sox.wav')
+
+        # 1. Generate original wav
+        data = get_wav_data('float32', num_channels, normalize=True, num_frames=duration * sample_rate)
+        save_wav(src_path, data, sample_rate)
+        # 2.1. Convert the original wav to sph with torchaudio
+        sox_io_backend.save(flc_path, load_wav(src_path)[0], sample_rate)
+        # 2.2. Convert the sph to wav with Sox
+        # converting to 32 bit because sph file has 24 bit depth which scipy cannot handle.
+        sox_utils.convert_audio_file(flc_path, wav_path, bit_depth=32)
+        # 2.3. Load
+        found = load_wav(wav_path)[0]
+
+        # 3.1. Convert the original wav to sph with SoX
+        sox_utils.convert_audio_file(src_path, flc_path_sox)
+        # 3.2. Convert the sph to wav with Sox
+        # converting to 32 bit because sph file has 24 bit depth which scipy cannot handle.
+        sox_utils.convert_audio_file(flc_path_sox, wav_path_sox, bit_depth=32)
+        # 3.3. Load
+        expected = load_wav(wav_path_sox)[0]
+
+        self.assertEqual(found, expected)
+
 
 @skipIfNoExec('sox')
 @skipIfNoExtension
@@ -262,6 +294,14 @@ def test_vorbis_large(self, sample_rate, num_channels, quality_level):
         self.assert_vorbis(sample_rate, num_channels, quality_level, two_hours)
     '''
 
+    @parameterized.expand(list(itertools.product(
+        [8000, 16000],
+        [1, 2],
+    )), name_func=name_func)
+    def test_sphere(self, sample_rate, num_channels):
+        """`sox_io_backend.save` can save sph format."""
+        self.assert_sphere(sample_rate, num_channels, duration=1)
+
 
 @skipIfNoExec('sox')
 @skipIfNoExtension

torchaudio/backend/sox_io_backend.py

@@ -58,6 +58,7 @@ def load(
         * FLAC
         * OGG/VORBIS
         * OPUS
+        * SPHERE
 
         To load ``MP3``, ``FLAC``, ``OGG/VORBIS``, ``OPUS`` and other codecs ``libsox`` does not
         handle natively, your installation of ``torchaudio`` has to be linked to ``libsox``
@@ -132,6 +133,7 @@ def save(
         * MP3
         * FLAC
         * OGG/VORBIS
+        * SPHERE
 
         To save ``MP3``, ``FLAC``, ``OGG/VORBIS``, and other codecs ``libsox`` does not
         handle natively, your installation of ``torchaudio`` has to be linked to ``libsox``
@@ -158,7 +160,7 @@ def save(
     """
     if compression is None:
         ext = str(filepath)[-3:].lower()
-        if ext == 'wav':
+        if ext in ['wav', 'sph']:
             compression = 0.
         elif ext == 'mp3':
             compression = -4.5

torchaudio/csrc/sox_utils.cpp

@@ -234,6 +234,8 @@ sox_encoding_t get_encoding(
       return SOX_ENCODING_FLOAT;
     throw std::runtime_error("Unsupported dtype.");
   }
+  if (filetype == "sph")
+    return SOX_ENCODING_SIGN2;
   throw std::runtime_error("Unsupported file type.");
 }
 
@@ -257,6 +259,8 @@ unsigned get_precision(
       return 32;
     throw std::runtime_error("Unsupported dtype.");
   }
+  if (filetype == "sph")
+    return 32;
   throw std::runtime_error("Unsupported file type.");
 }
 
@@ -285,6 +289,8 @@ sox_encodinginfo_t get_encodinginfo(
       return compression;
     if (filetype == "wav")
       return 0.;
+    if (filetype == "sph")
+      return 0.;
     throw std::runtime_error("Unsupported file type.");
   }();