pen的隨手筆記

2019年2月7日星期四

Android系統權限

Android系統權限

添加於manifest
<uses-permission android:name="android.permission.權限名稱" />

Android權限名稱

CALENDAR

READ_CALENDAR
WRITE_CALENDAR

CAMERA

CAMERA

CONTACTS

READ_CONTACTS
WRITE_CONTACTS
GET_ACCOUNTS

LOCATION

ACCESS_FINE_LOCATION
ACCESS_COARSE_LOCATION

MICROPHONE

RECORD_AUDIO

PHONE

READ_PHONE_STATE
CALL_PHONE
READ_CALL_LOG
WRITE_CALL_LOG
ADD_VOICEMAIL
USE_SIP
PROCESS_OUTGOING_CALLS

SENSORS

BODY_SENSORS

SMS

SEND_SMS
RECEIVE_SMS
READ_SMS
RECEIVE_WAP_PUSH
RECEIVE_MMS

STORAGE

READ_EXTERNAL_STORAGE
WRITE_EXTERNAL_STORAGE

Android執行時請求權限

public class MainActivity extends AppCompatActivity {

    final int MY_PERMISSIONS_REQUEST_READ_CONTACTS = 1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initial();
    }

    private void initial() {
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.READ_CONTACTS)
                != PackageManager.PERMISSION_GRANTED) {

                    //權限請求           
                    ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.READ_CONTACTS},
                    MY_PERMISSIONS_REQUEST_READ_CONTACTS);
        }
    }

//權限請求回應    
    @Override
    public void onRequestPermissionsResult(int requestCode,
                                           String permissions[], int[] grantResults) {
        switch (requestCode) {
            case MY_PERMISSIONS_REQUEST_READ_CONTACTS: {
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    //權限被接受
                } else {
                //權限被拒絕
                }
                return;
            }

        }
    }

}

以上以聯絡人權限為例，權限請求回應可依照個人需求不寫
manifest記得加

<uses-permission android:name="android.permission.READ_CONTACTS">

2019年2月5日星期二

python第三方庫 Unofficial Windows Binaries for Python Extension Packages

加州大學提供完整的Python Packages，所有庫缺失，可以先來這裡看看

網址:
https://www.lfd.uci.edu/~gohlke/pythonlibs/

如何安裝.whl文件

下載版本對應的.whl檔後，開啟cmd輸入
pip install 包位址/包名字.whl 即可安裝

使用pyAudio錄音及播放

pyAudio是開源聲音庫PortAudio(http://www.portaudio.com/)提供的Python庫

使用pyAudio播放聲音

import pyaudio
import wave

buf = 1024

wf = wave.open(r"C:\Users\yuli\Desktop\a\forest.wav", 'rb')

p = pyaudio.PyAudio()

stream = p.open(format = p.get_format_from_width(wf.getsampwidth()),
                channels = wf.getnchannels(),
                rate = wf.getframerate(),
                output = True)

while True:
    data = wf.readframes(buf)
    if data == "": break
    stream.write(data)

stream.close()
p.terminate()

pyAudio類的open函數參數:

rate - 取樣頻率
channel - 聲道

1=>mono為單聲道
2=>stereo為雙聲道(立體聲)

format - 取樣值量化格式

pyaudio.paFloat32 = 1
pyaudio.paInt32 = 2
pyaudio.paInt24 = 4
pyaudio.paInt16 = 8
pyaudio.paInt8 = 16
pyaudio.paUInt8 = 32
pyaudio.paCustomFormat = 65536

input - 若為True則為開啟輸入流
output - 若為True則為開啟輸出流
input_device_index - 輸入所使用的設備編號，不指定則為系統預設
output_device_index - 輸出所使用的設備編號，不指定則為系統預設
frames_per_buffer - 緩存塊大小
start - 是否立即開始輸入輸出流，不指定則為True

使用pyAudio錄音

from pyaudio import PyAudio, paInt16 
import numpy as np 
from datetime import datetime 
import wave 

def save_wave_file(filename, data): 
    wf = wave.open(filename, 'wb') 
    wf.setnchannels(1) 
    wf.setsampwidth(2) 
    wf.setframerate(SAMPLING_RATE) 
    wf.writeframes(b"".join(data)) 
    wf.close() 

NUM_SAMPLES = 2000      
SAMPLING_RATE = 8000    
LEVEL = 1500            
COUNT_NUM = 20          
SAVE_LENGTH = 8         

pa = PyAudio() 
stream = pa.open(format=paInt16, channels=1, rate=SAMPLING_RATE, input=True, 
                frames_per_buffer=NUM_SAMPLES) 

save_count = 0 
save_buffer = [] 

while True: 
    string_audio_data = stream.read(NUM_SAMPLES) 
    audio_data = np.fromstring(string_audio_data, dtype=np.short) 
    large_sample_count = np.sum( audio_data > LEVEL ) 
    print(np.max(audio_data))
    if large_sample_count > COUNT_NUM: 
        save_count = SAVE_LENGTH 
    else: 
        save_count -= 1 

    if save_count < 0: 
        save_count = 0 

    if save_count > 0: 
        save_buffer.append( string_audio_data ) 
    else: 
        if len(save_buffer) > 0: 
            filename = datetime.now().strftime("%Y-%m-%d_%H_%M_%S") + ".wav" 
            save_wave_file(filename, save_buffer) 
            save_buffer = [] 
            print(filename, "saved")

2019年2月7日 星期四