【移動應(yīng)用開發(fā)技術(shù)】Android中如何在安卓上開發(fā)一個微笑抓拍神器

【移動應(yīng)用開發(fā)技術(shù)】Android中如何在安卓上開發(fā)一個微笑抓拍神器

1、開發(fā)準備1.1在項目級gradle里添加華為maven倉buildscript

{

repositories

{

maven

{url

'/repo/'}

}

}allprojects

{

repositories

{

maven

{

url

'/repo/'}

}}1.2在應(yīng)用級的build.gradle里面加上SDK依賴dependencies{

//

引入基礎(chǔ)SDK

implementation

'com.huawei.hms:ml-computer-vision:00'

//

引入人臉檢測能力包

implementation

'com.huawei.hms:ml-computer-vision-face-recognition-model:00'

}1.3在AndroidManifest.xml文件里面增量添加模型自動下載<manifest

<application

<meta-data

android:name="com.huawei.hms.ml.DEPENDENCY"

android:value=

"face"/>

</application></manifest>1.4在AndroidManifest.xml文件里面申請相機和存儲權(quán)限<!--相機權(quán)限--><uses-permission

android:name="android.permission.CAMERA"

/><!--使用存儲權(quán)限--><uses-permission

android:name="android.permission.WRITE_EXTERNAL_STORAGE"

/>2、代碼開發(fā)2.1創(chuàng)建人臉分析器,檢測到微笑后進行拍照private

MLFaceAnalyzer

analyzer;private

void

createFaceAnalyzer()

{

MLFaceAnalyzerSetting

setting

=

new

MLFaceAnalyzerSetting.Factory()

.setFeatureType(MLFaceAnalyzerSetting.TYPE_FEATURES)

.setKeyPointType(MLFaceAnalyzerSetting.TYPE_UNSUPPORT_KEYPOINTS)

.setMinFaceProportion(0.1f)

.setTracingAllowed(true)

.create();

this.analyzer

=

MLAnalyzerFactory.getInstance().getFaceAnalyzer(setting);

this.analyzer.setTransactor(new

MLAnalyzer.MLTransactor<MLFace>()

{

@Override

public

void

destroy()

{

}

@Override

public

void

transactResult(MLAnalyzer.Result<MLFace>

result)

{

SparseArray<MLFace>

faceSparseArray

=

result.getAnalyseList();

int

flag

=

0;

for

(int

i

=

0;

i

<

faceSparseArray.size();

i++)

{

MLFaceEmotion

emotion

=

faceSparseArray.valueAt(i).getEmotions();

if

(emotion.getSmilingProbability()

>

smilingPossibility)

{

flag++;

}

}

if

(flag

>

faceSparseArray.size()

*

smilingRate

&&

safeToTakePicture)

{

safeToTakePicture

=

false;

mHandler.sendEmptyMessage(TAKE_PHOTO);

}

}

});}private

void

takePhoto()

{

this.mLensEngine.photograph(null,

new

LensEngine.PhotographListener()

{

@Override

public

void

takenPhotograph(byte[]

bytes)

{

mHandler.sendEmptyMessage(STOP_PREVIEW);

Bitmap

bitmap

=

BitmapFactory.decodeByteArray(bytes,

0,

bytes.length);

saveBitmapToDisk(bitmap);

}

});}2.2創(chuàng)建視覺引擎，捕捉相機動態(tài)視頻流后傳給分析器private

void

createLensEngine()

{

Context

context

=

this.getApplicationContext();

//

Create

LensEngine

this.mLensEngine

=

new

LensEngine.Creator(context,

this.analyzer).setLensType(this.lensType)

.applyDisplayDimension(640,

480)

.applyFps(25.0f)

.enableAutomaticFocus(true)

.create();}2.3動態(tài)權(quán)限申請，掛接分析器和視覺引擎創(chuàng)建代碼@Overridepublic

void

onCreate(Bundle

savedInstanceState)

{

super.onCreate(savedInstanceState);

this.setContentView(R.layout.activity_live_face_analyse);

if

(savedInstanceState

!=

null)

{

this.lensType

=

savedInstanceState.getInt("lensType");

}

this.mPreview

=

this.findViewById(R.id.preview);

this.createFaceAnalyzer();

this.findViewById(R.id.facingSwitch).setOnClickListener(this);

//

Checking

Camera

Permissions

if

(ActivityCompat.checkSelfPermission(this,

Manifest.permission.CAMERA)

==

PackageManager.PERMISSION_GRANTED)

{

this.createLensEngine();

}

else

{

this.requestCameraPermission();

}}

private

void

requestCameraPermission()

{

final

String[]

permissions

=

new

String[]{Manifest.permission.CAMERA,

Manifest.permission.WRITE_EXTERNAL_STORAGE};

if

(!ActivityCompat.shouldShowRequestPermissionRationale(this,

Manifest.permission.CAMERA))

{

ActivityCompat.requestPermissions(this,

permissions,

LiveFaceAnalyseActivity.CAMERA_PERMISSION_CODE);

return;

}}@Overridepublic

void

onRequestPermissionsResult(int

requestCode,

@NonNull

String[]

permissions,

@NonNull

int[]

grantResults)

{

if

(requestCode

!=

LiveFaceAnalyseActivity.CAMERA_PERMISSION_CODE)

{

super.onReq