Support MelBankOptions.

kaldifeat/python/csrc/mel-computations.cc

@@ -7,6 +7,7 @@
 #include <string>
 
 #include "kaldifeat/csrc/mel-computations.h"
+#include "kaldifeat/python/csrc/utils.h"
 
 namespace kaldifeat {
 
@@ -22,7 +23,12 @@ static void PybindMelBanksOptions(py::module &m) {
       .def_readwrite("debug_mel", &PyClass::debug_mel)
       .def_readwrite("htk_mode", &PyClass::htk_mode)
       .def("__str__",
-           [](const PyClass &self) -> std::string { return self.ToString(); });
+           [](const PyClass &self) -> std::string { return self.ToString(); })
+      .def("as_dict",
+           [](const PyClass &self) -> py::dict { return AsDict(self); })
+      .def_static("from_dict", [](py::dict dict) -> PyClass {
+        return MelBanksOptionsFromDict(dict);
+      });
 }
 
 void PybindMelComputations(py::module &m) { PybindMelBanksOptions(m); }

kaldifeat/python/csrc/utils.cc

@@ -17,6 +17,7 @@ namespace kaldifeat {
 
 FrameExtractionOptions FrameExtractionOptionsFromDict(py::dict dict) {
   FrameExtractionOptions opts;
+
   FROM_DICT(float_, samp_freq);
   FROM_DICT(float_, frame_shift_ms);
   FROM_DICT(float_, frame_length_ms);
@@ -27,11 +28,13 @@ FrameExtractionOptions FrameExtractionOptionsFromDict(py::dict dict) {
   FROM_DICT(bool_, round_to_power_of_two);
   FROM_DICT(float_, blackman_coeff);
   FROM_DICT(bool_, snip_edges);
+
   return opts;
 }
 
 py::dict AsDict(const FrameExtractionOptions &opts) {
   py::dict dict;
+
   AS_DICT(samp_freq);
   AS_DICT(frame_shift_ms);
   AS_DICT(frame_length_ms);
@@ -45,6 +48,33 @@ py::dict AsDict(const FrameExtractionOptions &opts) {
   return dict;
 }
 
+MelBanksOptions MelBanksOptionsFromDict(py::dict dict) {
+  MelBanksOptions opts;
+
+  FROM_DICT(int_, num_bins);
+  FROM_DICT(float_, low_freq);
+  FROM_DICT(float_, high_freq);
+  FROM_DICT(float_, vtln_low);
+  FROM_DICT(float_, vtln_high);
+  FROM_DICT(bool_, debug_mel);
+  FROM_DICT(bool_, htk_mode);
+
+  return opts;
+}
+py::dict AsDict(const MelBanksOptions &opts) {
+  py::dict dict;
+
+  AS_DICT(num_bins);
+  AS_DICT(low_freq);
+  AS_DICT(high_freq);
+  AS_DICT(vtln_low);
+  AS_DICT(vtln_high);
+  AS_DICT(debug_mel);
+  AS_DICT(htk_mode);
+
+  return dict;
+}
+
 #undef FROM_DICT
 #undef AS_DICT
 

kaldifeat/python/csrc/utils.h

@@ -6,13 +6,29 @@
 #define KALDIFEAT_PYTHON_CSRC_UTILS_H_
 
 #include "kaldifeat/csrc/feature-window.h"
+#include "kaldifeat/csrc/mel-computations.h"
 #include "kaldifeat/python/csrc/kaldifeat.h"
 
+/*
+ * This file contains code about `from_dict` and
+ * `to_dict` for various options in kaldifeat.
+ *
+ * Regarding `from_dict`, users don't need to provide
+ * all the fields in the options. If some fields
+ * are not provided, it just uses the default one.
+ *
+ * If the provided dict in `from_dict` is empty,
+ * all fields use their default values.
+ */
+
 namespace kaldifeat {
 
 FrameExtractionOptions FrameExtractionOptionsFromDict(py::dict dict);
 py::dict AsDict(const FrameExtractionOptions &opts);
 
+MelBanksOptions MelBanksOptionsFromDict(py::dict dict);
+py::dict AsDict(const MelBanksOptions &opts);
+
 }  // namespace kaldifeat
 
 #endif  // KALDIFEAT_PYTHON_CSRC_UTILS_H_

kaldifeat/python/tests/CMakeLists.txt

@@ -23,6 +23,7 @@ set(py_test_files
   test_spectrogram.py
   test_options.py
   test_frame_extraction_options.py
+  test_mel_bank_options.py
 )
 
 foreach(source IN LISTS py_test_files)

kaldifeat/python/tests/test_mel_bank_options.py

@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+#
+# Copyright (c)  2021  Xiaomi Corporation (authors: Fangjun Kuang)
+
+import kaldifeat
+
+
+def test_default():
+    opts = kaldifeat.MelBanksOptions()
+    assert opts.num_bins == 25
+    assert opts.low_freq == 20
+    assert opts.high_freq == 0
+    assert opts.vtln_low == 100
+    assert opts.vtln_high == -500
+    assert opts.debug_mel is False
+    assert opts.htk_mode is False
+
+
+def test_set_get():
+    opts = kaldifeat.MelBanksOptions()
+    opts.num_bins = 100
+    assert opts.num_bins == 100
+
+    opts.low_freq = 22
+    assert opts.low_freq == 22
+
+    opts.high_freq = 1
+    assert opts.high_freq == 1
+
+    opts.vtln_low = 101
+    assert opts.vtln_low == 101
+
+    opts.vtln_high = -100
+    assert opts.vtln_high == -100
+
+    opts.debug_mel = True
+    assert opts.debug_mel is True
+
+    opts.htk_mode = True
+    assert opts.htk_mode is True
+
+
+def test_from_empty_dict():
+    opts = kaldifeat.MelBanksOptions.from_dict({})
+    opts2 = kaldifeat.MelBanksOptions()
+
+    assert str(opts) == str(opts2)
+
+
+def test_from_dict_partial():
+    d = {"num_bins": 10, "debug_mel": True}
+
+    opts = kaldifeat.MelBanksOptions.from_dict(d)
+
+    opts2 = kaldifeat.MelBanksOptions()
+    assert str(opts) != str(opts2)
+
+    opts2.num_bins = 10
+    assert str(opts) != str(opts2)
+
+    opts2.debug_mel = True
+    assert str(opts) == str(opts2)
+
+    opts2.debug_mel = False
+    assert str(opts) != str(opts2)
+
+
+def test_from_dict_full_and_as_dict():
+    opts = kaldifeat.MelBanksOptions()
+    opts.num_bins = 80
+    opts.vtln_high = 2
+
+    d = opts.as_dict()
+    for key, value in d.items():
+        assert value == getattr(opts, key)
+
+    opts2 = kaldifeat.MelBanksOptions.from_dict(d)
+    assert str(opts2) == str(opts)
+
+    d["htk_mode"] = True
+    opts3 = kaldifeat.MelBanksOptions.from_dict(d)
+    assert opts3.htk_mode is True
+
+
+def main():
+    test_default()
+    test_set_get()
+    test_from_empty_dict()
+    test_from_dict_partial()
+    test_from_dict_full_and_as_dict()
+
+
+if __name__ == "__main__":
+    main()

kaldifeat/python/tests/test_options.py

@@ -16,18 +16,6 @@ sys.path.insert(0, f"{kaldi_feat_dir}/build/lib")
 import kaldifeat
 
 
-def test_mel_banks_options():
-    opts = kaldifeat.MelBanksOptions()
-    opts.num_bins = 23
-    opts.low_freq = 21
-    opts.high_freq = 8000
-    opts.vtln_low = 101
-    opts.vtln_high = -501
-    opts.debug_mel = True
-    opts.htk_mode = True
-    print(opts)
-
-
 def test_fbank_options():
     opts = kaldifeat.FbankOptions()
     frame_opts = opts.frame_opts
@@ -153,7 +141,6 @@ def test_plp_options():
 
 
 def main():
-    test_mel_banks_options()
     test_fbank_options()
     test_mfcc_options()
     test_spectogram_options()