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Add Python ASR example with alsa (#324)
1 parent 3c7724c commit 87899c2

11 files changed

+227
-4
lines changed

‎CMakeLists.txt

+2-1
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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cmake_minimum_required(VERSION 3.13 FATAL_ERROR)
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project(sherpa-ncnn)
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4-
set(SHERPA_NCNN_VERSION "2.1.9")
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set(SHERPA_NCNN_VERSION "2.1.10")
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# Disable warning about
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#
@@ -106,6 +106,7 @@ if(SHERPA_NCNN_ENABLE_BINARY AND UNIX AND NOT APPLE)
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include(CheckIncludeFileCXX)
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check_include_file_cxx(alsa/asoundlib.h SHERPA_NCNN_HAS_ALSA)
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if(SHERPA_NCNN_HAS_ALSA)
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message(STATUS "With Alsa")
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add_definitions(-DSHERPA_NCNN_ENABLE_ALSA=1)
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elseif(UNIX AND NOT APPLE)
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message(WARNING "\

‎python-api-examples/speech-recognition-from-microphone-with-endpoint-detection-alsa.py

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@@ -0,0 +1,111 @@
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#!/usr/bin/env python3
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# Real-time speech recognition from a microphone with sherpa-ncnn Python API
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# with endpoint detection.
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#
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# Note: This script uses ALSA and works only on Linux systems, especially
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# for embedding Linux systems and for running Linux on Windows using WSL.
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#
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# Please refer to
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# https://k2-fsa.github.io/sherpa/ncnn/pretrained_models/index.html
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# to download pre-trained models
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import argparse
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import sys
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import sherpa_ncnn
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def get_args():
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parser = argparse.ArgumentParser(
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formatter_class=argparse.ArgumentDefaultsHelpFormatter
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)
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parser.add_argument(
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"--device-name",
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type=str,
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required=True,
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help="""
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The device name specifies which microphone to use in case there are several
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on your system. You can use
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arecord -l
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to find all available microphones on your computer. For instance, if it outputs
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**** List of CAPTURE Hardware Devices ****
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card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
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Subdevices: 1/1
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Subdevice #0: subdevice #0
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and if you want to select card 3 and the device 0 on that card, please use:
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plughw:3,0
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as the device_name.
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""",
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)
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return parser.parse_args()
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def create_recognizer():
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# Please replace the model files if needed.
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# See https://k2-fsa.github.io/sherpa/ncnn/pretrained_models/index.html
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# for download links.
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recognizer = sherpa_ncnn.Recognizer(
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tokens="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/tokens.txt",
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encoder_param="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/encoder_jit_trace-pnnx.ncnn.param",
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encoder_bin="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/encoder_jit_trace-pnnx.ncnn.bin",
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decoder_param="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/decoder_jit_trace-pnnx.ncnn.param",
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decoder_bin="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/decoder_jit_trace-pnnx.ncnn.bin",
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joiner_param="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/joiner_jit_trace-pnnx.ncnn.param",
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joiner_bin="./sherpa-ncnn-conv-emformer-transducer-2022-12-06/joiner_jit_trace-pnnx.ncnn.bin",
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num_threads=4,
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decoding_method="modified_beam_search",
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enable_endpoint_detection=True,
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rule1_min_trailing_silence=2.4,
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rule2_min_trailing_silence=1.2,
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rule3_min_utterance_length=300,
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hotwords_file="",
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hotwords_score=1.5,
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)
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return recognizer
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def main():
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args = get_args()
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device_name = args.device_name
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print(f"device_name: {device_name}")
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alsa = sherpa_ncnn.Alsa(device_name)
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recognizer = create_recognizer()
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print("Started! Please speak")
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sample_rate = recognizer.sample_rate
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samples_per_read = int(0.1 * sample_rate) # 0.1 second = 100 ms
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last_result = ""
87+
segment_id = 0
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while True:
90+
samples = alsa.read(samples_per_read) # a blocking read
91+
recognizer.accept_waveform(sample_rate, samples)
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is_endpoint = recognizer.is_endpoint
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result = recognizer.text
96+
if result and (last_result != result):
97+
last_result = result
98+
print("\r{}:{}".format(segment_id, result), end="", flush=True)
99+
100+
if is_endpoint:
101+
if result:
102+
print("\r{}:{}".format(segment_id, result), flush=True)
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segment_id += 1
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recognizer.reset()
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106+
107+
if __name__ == "__main__":
108+
try:
109+
main()
110+
except KeyboardInterrupt:
111+
print("\nCaught Ctrl + C. Exiting")

‎sherpa-ncnn/csrc/alsa.cc

+1-1
Original file line numberDiff line numberDiff line change
@@ -62,7 +62,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
6262
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and if you want to select card 3 and the device 0 on that card, please use:
6464
65-
hw:3,0
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plughw:3,0
6666
6767
)";
6868

‎sherpa-ncnn/csrc/sherpa-ncnn-alsa.cc

+1-1
Original file line numberDiff line numberDiff line change
@@ -67,7 +67,7 @@ card 3: UACDemoV10 [UACDemoV1.0], device 0: USB Audio [USB Audio]
6767
6868
and if you want to select card 3 and the device 0 on that card, please use:
6969
70-
hw:3,0
70+
plughw:3,0
7171
7272
as the device_name.
7373
)usage";

‎sherpa-ncnn/csrc/stream.cc

+1
Original file line numberDiff line numberDiff line change
@@ -19,6 +19,7 @@
1919
#include "sherpa-ncnn/csrc/stream.h"
2020

2121
#include <iostream>
22+
#include <utility>
2223

2324
namespace sherpa_ncnn {
2425

‎sherpa-ncnn/python/csrc/CMakeLists.txt

+13
Original file line numberDiff line numberDiff line change
@@ -11,6 +11,12 @@ set(srcs
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stream.cc
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)
1313

14+
if(SHERPA_NCNN_HAS_ALSA)
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list(APPEND srcs ${CMAKE_SOURCE_DIR}/sherpa-ncnn/csrc/alsa.cc alsa.cc)
16+
else()
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list(APPEND srcs faked-alsa.cc)
18+
endif()
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1420
pybind11_add_module(_sherpa_ncnn ${srcs})
1521
target_link_libraries(_sherpa_ncnn PRIVATE sherpa-ncnn-core)
1622

@@ -28,6 +34,13 @@ if(NOT WIN32)
2834
target_link_libraries(_sherpa_ncnn PRIVATE "-Wl,-rpath,${SHERPA_NCNN_RPATH_ORIGIN}/sherpa_ncnn/lib")
2935
endif()
3036

37+
if(SHERPA_NCNN_HAS_ALSA)
38+
if(DEFINED ENV{SHERPA_NCNN_ALSA_LIB_DIR})
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target_link_libraries(_sherpa_ncnn PRIVATE -L$ENV{SHERPA_NCNN_ALSA_LIB_DIR} -lasound)
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else()
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target_link_libraries(_sherpa_ncnn PRIVATE asound)
42+
endif()
43+
endif()
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3245
install(TARGETS _sherpa_ncnn
3346
DESTINATION ../

‎sherpa-ncnn/python/csrc/alsa.cc

+30
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@@ -0,0 +1,30 @@
1+
// sherpa-ncnn/python/csrc/alsa.cc
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//
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// Copyright (c) 2024 Xiaomi Corporation
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5+
#include "sherpa-ncnn/python/csrc/alsa.h"
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7+
#include <vector>
8+
9+
#include "sherpa-ncnn/csrc/alsa.h"
10+
11+
namespace sherpa_ncnn {
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13+
void PybindAlsa(py::module *m) {
14+
using PyClass = Alsa;
15+
py::class_<PyClass>(*m, "Alsa")
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.def(py::init<const char *>(), py::arg("device_name"),
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py::call_guard<py::gil_scoped_release>())
18+
.def(
19+
"read",
20+
[](PyClass &self, int32_t num_samples) -> std::vector<float> {
21+
return self.Read(num_samples);
22+
},
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py::arg("num_samples"), py::call_guard<py::gil_scoped_release>())
24+
.def_property_readonly("expected_sample_rate",
25+
&PyClass::GetExpectedSampleRate)
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.def_property_readonly("actual_sample_rate",
27+
&PyClass::GetActualSampleRate);
28+
}
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} // namespace sherpa_ncnn

‎sherpa-ncnn/python/csrc/alsa.h

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@@ -0,0 +1,16 @@
1+
// sherpa-ncnn/python/csrc/alsa.h
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//
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// Copyright (c) 2024 Xiaomi Corporation
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5+
#ifndef SHERPA_NCNN_PYTHON_CSRC_ALSA_H_
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#define SHERPA_NCNN_PYTHON_CSRC_ALSA_H_
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#include "sherpa-ncnn/python/csrc/sherpa-ncnn.h"
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namespace sherpa_ncnn {
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void PybindAlsa(py::module *m);
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} // namespace sherpa_ncnn
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16+
#endif // SHERPA_NCNN_PYTHON_CSRC_ALSA_H_

‎sherpa-ncnn/python/csrc/faked-alsa.cc

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1+
// sherpa-ncnn/python/csrc/faked-alsa.cc
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//
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// Copyright (c) 2024 Xiaomi Corporation
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5+
#include "sherpa-ncnn/csrc/macros.h"
6+
#include "sherpa-ncnn/python/csrc/alsa.h"
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8+
namespace sherpa_ncnn {
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10+
class FakedAlsa {
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public:
12+
explicit FakedAlsa(const char *) {
13+
SHERPA_NCNN_LOGE("This function is for Linux only.");
14+
#if (SHERPA_NCNN_ENABLE_ALSA == 0) && (defined(__unix__) || defined(__unix))
15+
SHERPA_NCNN_LOGE(R"doc(
16+
sherpa-ncnn is compiled without alsa support. To enable that, please run
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(1) sudo apt-get install alsa-utils libasound2-dev
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(2) rebuild sherpa-ncnn
19+
)doc");
20+
#endif
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exit(-1);
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}
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24+
std::vector<float> Read(int32_t) const { return {}; }
25+
int32_t GetExpectedSampleRate() const { return -1; }
26+
int32_t GetActualSampleRate() const { return -1; }
27+
};
28+
29+
void PybindAlsa(py::module *m) {
30+
using PyClass = FakedAlsa;
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py::class_<PyClass>(*m, "Alsa")
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.def(py::init<const char *>(), py::arg("device_name"))
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.def(
34+
"read",
35+
[](PyClass &self, int32_t num_samples) -> std::vector<float> {
36+
return self.Read(num_samples);
37+
},
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py::arg("num_samples"), py::call_guard<py::gil_scoped_release>())
39+
.def_property_readonly("expected_sample_rate",
40+
&PyClass::GetExpectedSampleRate)
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.def_property_readonly("actual_sample_rate",
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&PyClass::GetActualSampleRate);
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}
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} // namespace sherpa_ncnn
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47+
#endif // SHERPA_NCNN_PYTHON_CSRC_FAKED_ALSA_H_

‎sherpa-ncnn/python/csrc/sherpa-ncnn.cc

+3
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@@ -18,6 +18,7 @@
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1919
#include "sherpa-ncnn/python/csrc/sherpa-ncnn.h"
2020

21+
#include "sherpa-ncnn/python/csrc/alsa.h"
2122
#include "sherpa-ncnn/python/csrc/decoder.h"
2223
#include "sherpa-ncnn/python/csrc/display.h"
2324
#include "sherpa-ncnn/python/csrc/endpoint.h"
@@ -39,6 +40,8 @@ PYBIND11_MODULE(_sherpa_ncnn, m) {
3940
PybindRecognizer(&m);
4041

4142
PybindDisplay(&m);
43+
44+
PybindAlsa(&m);
4245
}
4346

4447
} // namespace sherpa_ncnn

‎sherpa-ncnn/python/sherpa_ncnn/__init__.py

+2-1
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@@ -1,2 +1,3 @@
1+
from _sherpa_ncnn import Alsa, Display
2+
13
from .recognizer import Recognizer
2-
from _sherpa_ncnn import Display

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