Now a days lot of apps offer users to take pictures and record videos for various kind of purposes. This tutorial describes how to do the same in your applications.
Integrating camera can be done in two ways. One is to use android inbuilt camera app which is very easy process. This method won’t give you much control over camera as everything is taken care by inbuilt camera app. This way will be appropriate when your app need just a picture or video from camera.
Second way is to build a custom camera interface and adding the functionality. This needs higher effort as we have to do everything by our own. Building custom camera interface will be useful when you are building an app which mainly deals with images and videos like Instagram.
This tutorial covers the first scenario which is using android in build camera app in your application.
Let’s start by creating a new project
1. Create a new project in Eclipse from File ⇒ New ⇒ Android ⇒ Application Project and fill all the required information. I left my main activity as MainActivity.java
Adding Permissions / Features
2. Working with camera needs set of permissions and features in the AndroidManifest.xml file. Add following in your AndroidManifest.xml
android.hardware.camera – Required to use camera hardware
WRITE_EXTERNAL_STORAGE – Required to store images / video in external storage
RECORD_AUDIO – Needed when recording video with audio
WRITE_EXTERNAL_STORAGE – Required to store images / video in external storage
RECORD_AUDIO – Needed when recording video with audio
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="info.androidhive.androidcameraapi"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<!-- Accessing camera hardware -->
<uses-feature android:name="android.hardware.camera" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="info.androidhive.androidcameraapi.MainActivity"
android:label="@string/app_name"
android:configChanges="orientation|keyboard|keyboardHidden"
android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
3. For demo purpose I have created a simple layout with two Buttons, ImageView andVideoView. Open your layout file of your main activity activity_main.xml and paste the following code.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
android:baselineAligned="false"
tools:context=".MainActivity" >
<LinearLayout
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1"
android:gravity="center"
android:orientation="vertical" >
<!-- Capture picture button -->
<Button
android:id="@+id/btnCapturePicture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Take a Picture"
android:layout_marginBottom="10dp"/>
<!-- Record video button -->
<Button
android:id="@+id/btnRecordVideo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Record a Video" />
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1"
android:orientation="vertical"
android:padding="10dp">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Preview"
android:padding="10dp"
android:textSize="15dp"/>
<!-- To display picture taken -->
<ImageView
android:id="@+id/imgPreview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone" />
<!-- To preview video recorded -->
<VideoView
android:id="@+id/videoPreview"
android:layout_width="wrap_content"
android:layout_height="400dp"
android:visibility="gone" />
</LinearLayout>
</LinearLayout>
4. In MainActivity.java I started with adding code like declaring required variables, referencing the xml UI elements and adding button click listeners.
I kept default location to store images and videos in “Hello Camera” directory which will be created under SD card Pictures/Hello Camera
public class MainActivity extends Activity {
// Activity request codes
private static final int CAMERA_CAPTURE_IMAGE_REQUEST_CODE = 100;
private static final int CAMERA_CAPTURE_VIDEO_REQUEST_CODE = 200;
public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;
// directory name to store captured images and videos
private static final String IMAGE_DIRECTORY_NAME = "Hello Camera";
private Uri fileUri; // file url to store image/video
private ImageView imgPreview;
private VideoView videoPreview;
private Button btnCapturePicture, btnRecordVideo;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imgPreview = (ImageView) findViewById(R.id.imgPreview);
videoPreview = (VideoView) findViewById(R.id.videoPreview);
btnCapturePicture = (Button) findViewById(R.id.btnCapturePicture);
btnRecordVideo = (Button) findViewById(R.id.btnRecordVideo);
/**
* Capture image button click event
* */
btnCapturePicture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// capture picture
captureImage();
}
});
/**
* Record video button click event
*/
btnRecordVideo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
recordVideo();
}
});
}
}
Checking Camera Availability
5. You might think about the scenario if the device does’t have the camera. So before using any camera feature, it is better to check availability of the camera. This can be done in two ways
a. Defining the camera feature in AndroidManifest.xml
By adding android.hardware.camera feature in manifest file, Google Play prevents the app to be installed on devices those doesn’t have camera.
b. Checking in code manually
You can also do a check in the code.
You can also do a check in the code.
/**
* Checking device has camera hardware or not
* */
private boolean isDeviceSupportCamera() {
if (getApplicationContext().getPackageManager().hasSystemFeature(
PackageManager.FEATURE_CAMERA)) {
// this device has a camera
return true;
} else {
// no camera on this device
return false;
}
}
Taking a Picture
6. As we are using android’s inbuilt camera app, launching the camera and taking the picture can done with very few lines of code using the power of Intent.
MediaStore.ACTION_IMAGE_CAPTURE – Requesting camera app to capture image
MediaStore.EXTRA_OUTPUT – Specifying a path where the image has to be stored
MediaStore.EXTRA_OUTPUT – Specifying a path where the image has to be stored
captureImage() function will launch the camera to snap a picture.
/*
* Capturing Camera Image will lauch camera app requrest image capture
*/
private void captureImage() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// start the image capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
}
7. As we are starting an activity using startActivityForResult(), we can expect some result inonActivityResult() method. Override this method in your activity like below. We also can check whether the user successfully took the picture or cancelled the camera.
/**
* Receiving activity result method will be called after closing the camera
* */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// if the result is capturing Image
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// successfully captured the image
// display it in image view
previewCapturedImage();
} else if (resultCode == RESULT_CANCELED) {
// user cancelled Image capture
Toast.makeText(getApplicationContext(),
"User cancelled image capture", Toast.LENGTH_SHORT)
.show();
} else {
// failed to capture image
Toast.makeText(getApplicationContext(),
"Sorry! Failed to capture image", Toast.LENGTH_SHORT)
.show();
}
}
}
Displaying Captured Image
As we used inbuilt camera app to capture the picture we won’t get the image in onActivityResult()method. In this case data parameter will be always null. We have to use fileUri to get the file path and display the image
8. onActivityResult() we use CAMERA_CAPTURE_IMAGE_REQUEST_CODE to check whether response came from Image Capture activity or Video Capture acivity. Call previewCapturedImage() in onActivityResult after doing this check.
/*
* Display image from a path to ImageView
*/
private void previewCapturedImage() {
try {
// hide video preview
videoPreview.setVisibility(View.GONE);
imgPreview.setVisibility(View.VISIBLE);
// bimatp factory
BitmapFactory.Options options = new BitmapFactory.Options();
// downsizing image as it throws OutOfMemory Exception for larger
// images
options.inSampleSize = 8;
final Bitmap bitmap = BitmapFactory.decodeFile(fileUri.getPath(),
options);
imgPreview.setImageBitmap(bitmap);
} catch (NullPointerException e) {
e.printStackTrace();
}
}
Recording a Video
9. Launching camera to record video is same as capturing image. But instead ofMediaStore.ACTION_IMAGE_CAPTURE we use MediaStore.ACTION_VIDEO_CAPTURE.
Here we also define video quality using MediaStore.EXTRA_VIDEO_QUALITY flag. Keeping this value as 1 records video at high quality with higher file size and keeping 0 records the video at lower quality and lower file size.
Call following function on record video button click event
/*
* Recording video
*/
private void recordVideo() {
Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);
// set video quality
// 1- for high quality video
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// start the video capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_VIDEO_REQUEST_CODE);
}
And in onActivityResult() method check the success of recording.
/**
* Receiving activity result method will be called after closing the camera
* */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// if the result is capturing Image
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
// code to check capture image response
} else if (requestCode == CAMERA_CAPTURE_VIDEO_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// video successfully recorded
// preview the recorded video
previewVideo();
} else if (resultCode == RESULT_CANCELED) {
// user cancelled recording
Toast.makeText(getApplicationContext(),
"User cancelled video recording", Toast.LENGTH_SHORT)
.show();
} else {
// failed to record video
Toast.makeText(getApplicationContext(),
"Sorry! Failed to record video", Toast.LENGTH_SHORT)
.show();
}
}
}
Previewing Recorded Video
10. Following function will play recorded video in VideoView. Call this method in onActivityResult method after checking RESULT_OK for camera response
/*
* Previewing recorded video
*/
private void previewVideo() {
try {
// hide image preview
imgPreview.setVisibility(View.GONE);
videoPreview.setVisibility(View.VISIBLE);
videoPreview.setVideoPath(fileUri.getPath());
// start playing
videoPreview.start();
} catch (Exception e) {
e.printStackTrace();
}
}
Avoiding NullPointerException after taking camera picture
11. It is known issue that everybody faces a NullPointerException while working with inbuilt camera application. When we launch the camera it actually restarts our activity which causes fileUri to be null. So when we use fileUri to display captured image or recorded video, we will get NullPointerException.
So in order to fix it we have to use onSaveInstanceState() and onRestoreInstanceState() to retain fileUri value. Add following code in MainActivity.java
/**
* Here we store the file url as it will be null after returning from camera
* app
*/
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// save file url in bundle as it will be null on scren orientation
// changes
outState.putParcelable("file_uri", fileUri);
}
/*
* Here we restore the fileUri again
*/
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
// get the file url
fileUri = savedInstanceState.getParcelable("file_uri");
}
Helper Methods
12. Add following methods in your main activity class. These methods helps in creating and getting files from SD card.
/**
* Creating file uri to store image/video
*/
public Uri getOutputMediaFileUri(int type) {
return Uri.fromFile(getOutputMediaFile(type));
}
/*
* returning image / video
*/
private static File getOutputMediaFile(int type) {
// External sdcard location
File mediaStorageDir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
IMAGE_DIRECTORY_NAME);
// Create the storage directory if it does not exist
if (!mediaStorageDir.exists()) {
if (!mediaStorageDir.mkdirs()) {
Log.d(IMAGE_DIRECTORY_NAME, "Oops! Failed create "
+ IMAGE_DIRECTORY_NAME + " directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
Locale.getDefault()).format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "IMG_" + timeStamp + ".jpg");
} else if (type == MEDIA_TYPE_VIDEO) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "VID_" + timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
It is advisable to use a real device and test the application.
Final Code
Here is the complete code of MainActivity.java
package info.androidhive.androidcameraapi;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import android.widget.VideoView;
public class MainActivity extends Activity {
// Activity request codes
private static final int CAMERA_CAPTURE_IMAGE_REQUEST_CODE = 100;
private static final int CAMERA_CAPTURE_VIDEO_REQUEST_CODE = 200;
public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;
// directory name to store captured images and videos
private static final String IMAGE_DIRECTORY_NAME = "Hello Camera";
private Uri fileUri; // file url to store image/video
private ImageView imgPreview;
private VideoView videoPreview;
private Button btnCapturePicture, btnRecordVideo;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imgPreview = (ImageView) findViewById(R.id.imgPreview);
videoPreview = (VideoView) findViewById(R.id.videoPreview);
btnCapturePicture = (Button) findViewById(R.id.btnCapturePicture);
btnRecordVideo = (Button) findViewById(R.id.btnRecordVideo);
/**
* Capture image button click event
*/
btnCapturePicture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// capture picture
captureImage();
}
});
/**
* Record video button click event
*/
btnRecordVideo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
recordVideo();
}
});
// Checking camera availability
if (!isDeviceSupportCamera()) {
Toast.makeText(getApplicationContext(),
"Sorry! Your device doesn't support camera",
Toast.LENGTH_LONG).show();
// will close the app if the device does't have camera
finish();
}
}
/**
* Checking device has camera hardware or not
* */
private boolean isDeviceSupportCamera() {
if (getApplicationContext().getPackageManager().hasSystemFeature(
PackageManager.FEATURE_CAMERA)) {
// this device has a camera
return true;
} else {
// no camera on this device
return false;
}
}
/**
* Capturing Camera Image will lauch camera app requrest image capture
*/
private void captureImage() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// start the image capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
}
/**
* Here we store the file url as it will be null after returning from camera
* app
*/
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// save file url in bundle as it will be null on scren orientation
// changes
outState.putParcelable("file_uri", fileUri);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
// get the file url
fileUri = savedInstanceState.getParcelable("file_uri");
}
/**
* Recording video
*/
private void recordVideo() {
Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);
// set video quality
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file
// name
// start the video capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_VIDEO_REQUEST_CODE);
}
/**
* Receiving activity result method will be called after closing the camera
* */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// if the result is capturing Image
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// successfully captured the image
// display it in image view
previewCapturedImage();
} else if (resultCode == RESULT_CANCELED) {
// user cancelled Image capture
Toast.makeText(getApplicationContext(),
"User cancelled image capture", Toast.LENGTH_SHORT)
.show();
} else {
// failed to capture image
Toast.makeText(getApplicationContext(),
"Sorry! Failed to capture image", Toast.LENGTH_SHORT)
.show();
}
} else if (requestCode == CAMERA_CAPTURE_VIDEO_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
// video successfully recorded
// preview the recorded video
previewVideo();
} else if (resultCode == RESULT_CANCELED) {
// user cancelled recording
Toast.makeText(getApplicationContext(),
"User cancelled video recording", Toast.LENGTH_SHORT)
.show();
} else {
// failed to record video
Toast.makeText(getApplicationContext(),
"Sorry! Failed to record video", Toast.LENGTH_SHORT)
.show();
}
}
}
/**
* Display image from a path to ImageView
*/
private void previewCapturedImage() {
try {
// hide video preview
videoPreview.setVisibility(View.GONE);
imgPreview.setVisibility(View.VISIBLE);
// bimatp factory
BitmapFactory.Options options = new BitmapFactory.Options();
// downsizing image as it throws OutOfMemory Exception for larger
// images
options.inSampleSize = 8;
final Bitmap bitmap = BitmapFactory.decodeFile(fileUri.getPath(),
options);
imgPreview.setImageBitmap(bitmap);
} catch (NullPointerException e) {
e.printStackTrace();
}
}
/**
* Previewing recorded video
*/
private void previewVideo() {
try {
// hide image preview
imgPreview.setVisibility(View.GONE);
videoPreview.setVisibility(View.VISIBLE);
videoPreview.setVideoPath(fileUri.getPath());
// start playing
videoPreview.start();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* ------------ Helper Methods ----------------------
* */
/**
* Creating file uri to store image/video
*/
public Uri getOutputMediaFileUri(int type) {
return Uri.fromFile(getOutputMediaFile(type));
}
/**
* returning image / video
*/
private static File getOutputMediaFile(int type) {
// External sdcard location
File mediaStorageDir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
IMAGE_DIRECTORY_NAME);
// Create the storage directory if it does not exist
if (!mediaStorageDir.exists()) {
if (!mediaStorageDir.mkdirs()) {
Log.d(IMAGE_DIRECTORY_NAME, "Oops! Failed create "
+ IMAGE_DIRECTORY_NAME + " directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
Locale.getDefault()).format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "IMG_" + timeStamp + ".jpg");
} else if (type == MEDIA_TYPE_VIDEO) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "VID_" + timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
}
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