簡介
安卓api提供了Camera類控制相機捕獲圖像,在api21以後,安卓也提供了Camera2,Camera變得過時了,但爲了兼容性,這裏還是使用Camera。
對於錄製視頻,可以使用MediaRecorder,這個可看安卓官方api文檔
使用
使用Camera進行拍照攝像前,你得先申請權限:
<!-- 相機權限 -->
<uses-permission android:name="android.permission.CAMERA" />
<!-- 錄音權限 -->
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<!-- 相機模塊 -->
<uses-feature android:name="android.hardware.camera"/>
<!-- 自動對焦模塊 -->
<uses-feature android:name="android.hardware.camera.autofocus"/>
接着,是相機預覽流程:
- Camera.open(int)獲取Camera實例
- setParameters設置相機參數
- setDisplayOrientation設置正確預覽方向
- 關聯SurfaceView,用於展示預覽畫面
- startPreview開始預覽,stopPreview停止預覽
- release釋放相機資源
錄像流程:
- 創建MediaRecorder對象,用於錄製音頻視頻
- 關聯MediaRecorder和Camera,捕獲從Camera傳來的畫面
- 設置MediaRecorder相關參數,視頻格式、編碼、大小等等
- setOrientationHint可設置視頻最終旋轉角度
- start開始錄製,stop停止錄製
- release釋放資源
爲了防止篇幅過長,我這裏就不展示全部代碼了,詳細代碼請看:github源碼
接下來我會就其中一些關鍵點列舉出來:
視頻質量
視頻質量直接影響視頻清晰度和文件大小,這個可以根據個人需求調整,碼率不宜過小也不宜過大。
/**
* 獲取適合的視頻質量配置
* 影響視頻清晰度和文件大小,根據自身需要調整
* @param cameraID 攝像頭ID
*/
fun getBestCamcorderProfile(cameraID: Int): CamcorderProfile? {
var profile: CamcorderProfile? = null
when {
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_1080P) -> { //1080P,優先
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_1080P)
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_720P) -> { //720P
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_720P)
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_480P) -> { //480P
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_480P)
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_HIGH) -> {//高品質
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_HIGH)
profile.videoBitRate /= 8
return profile
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_CIF) -> {
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_CIF)
return profile
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_QVGA) -> {
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_QVGA)
}
CamcorderProfile.hasProfile(cameraID, CamcorderProfile.QUALITY_LOW) -> {
profile = CamcorderProfile.get(cameraID, CamcorderProfile.QUALITY_LOW)
}
}
if (profile != null) {
//視頻碼率
profile.videoBitRate = 6000000
}
return profile
}
視頻預覽角度
/**
* 根據屏幕方向獲取對應預覽角度
* setDisplayOrientation只能改變預覽的角度,與視頻最終結果角度無關
* @param cameraID 相機ID
*/
fun getCameraPreviewOrientation(cameraID: Int, activity: Activity): Int {
val info = Camera.CameraInfo();
Camera.getCameraInfo(cameraID, info);
//屏幕選擇角度
val rotation = activity.windowManager.defaultDisplay.rotation
var degrees = 0
when (rotation) {
Surface.ROTATION_0 ->
degrees = 0
Surface.ROTATION_90 ->
degrees = 90
Surface.ROTATION_180 ->
degrees = 180
Surface.ROTATION_270 ->
degrees = 270
}
var result = 90
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
result = (info.orientation + degrees) % 360
result = (360 - result) % 360
} else {
result = (info.orientation - degrees + 360) % 360
}
return result;
}
相機預覽
/**
* 初始化相機設置並開啓預覽
*/
private fun startPreview() {
try {
//開啓後置攝像頭
camera = Camera.open(Camera.CameraInfo.CAMERA_FACING_BACK)
//設置預覽角度
val rotation = CameraUtil.getCameraPreviewOrientation(Camera.CameraInfo.CAMERA_FACING_BACK,this)
camera?.setDisplayOrientation(rotation)
// 在SurfaceView上預覽
camera?.setPreviewDisplay(sv_camera.holder)
val parameters = camera?.getParameters()
//獲取支持的預覽大小,注意這裏獲取的寬高是根據橫屏的
val sizes = parameters?.supportedPreviewSizes
//寬高建議根據橫豎屏切換
val previewSize =
CameraUtil.findFitPreviewSize(sv_camera.height,sv_camera.width,sizes)
if (previewSize != null) {
//設置預覽大小
parameters?.setPreviewSize(previewSize.width, previewSize.height)
}
//設置自動對焦模式
CameraUtil.setAutoFocusMode(parameters)
camera?.setParameters(parameters)
//開始預覽
camera?.startPreview()
} catch (e: Exception) {
Log.e("Test", "出錯了", e)
}
}
視頻錄製
/**
* 開始錄製
* 注意方法調用的先後順序
*/
private fun startRecorder() {
if (camera == null) {
return
}
if (recorder != null) {
stopRecord()
}
try {
val videoSize = CameraUtil.findFitVideoSize(camera!!.parameters,
sv_camera.height / sv_camera.width.toFloat()
)
//先停止camera預覽,釋放camera
camera?.stopPreview()
camera?.unlock()
//創建MediaRecorder對象
recorder = MediaRecorder()
//關聯camera
recorder?.setCamera(camera)
//設置視頻角度;
val rotation =
CameraUtil.getCameraPreviewOrientation(Camera.CameraInfo.CAMERA_FACING_BACK, this)
recorder?.setOrientationHint(rotation)
//設置預覽區域
recorder?.setPreviewDisplay(sv_camera.holder.surface)
//設置音頻來源
recorder?.setAudioSource(MediaRecorder.AudioSource.MIC)
//設置視頻來源,來自攝像頭
recorder?.setVideoSource(MediaRecorder.VideoSource.CAMERA)
//設置輸出格式
// recorder?.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4)
val profile = CameraUtil.getBestCamcorderProfile(Camera.CameraInfo.CAMERA_FACING_BACK)
if (profile != null) {
//設置視頻碼率
recorder?.setProfile(profile)
}
//設置視頻幀率,注意設備支持
recorder?.setVideoFrameRate(30)
//設置視頻寬高
recorder?.setVideoSize(videoSize.width, videoSize.height)
val file =
File(getExternalFilesDir(Environment.DIRECTORY_MOVIES)?.absolutePath, "test.mp4")
//設置音頻文件的存儲位置 {
recorder?.setOutputFile(file.absolutePath)
//準備
recorder?.prepare()
//開始錄製
recorder?.start()
ct_time.start()
} catch (e: Exception) {
Log.e("Test", e.message, e)
}
}
以上就是Camera+MediaRecord錄製視頻的方法!打完收工!有問題大家提出來討論一下。