I am developing an application where I need to convert an Image to PDF. I tried something, but the issue is, Image size in that PDF is very very small. I need solution to fix this. Also I am looking for converting multiple Images into single PDF document. I will post the code which I tried.
public void convertPDF(byte[] path)
{
String FILE = "mnt/sdcard/FirstPdf.pdf";
Document document=new Document();
try {
PdfWriter.getInstance(document, new FileOutputStream(FILE));
document.open();
try {
image=Image.getInstance(path);
document.add(new Paragraph("My Heading"));
document.add(image);
document.close();
} catch (IOException e) {
e.printStackTrace();
}
} catch (DocumentException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
When I convert Bitmap to Byte array, I am compressing the image and I guess, that's the reason. Without compressing the image, I am unable to convert Bitmap to Byte Array.
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG,100,stream);
byte[] byteArray=stream.toByteArray();
convertPDF(byteArray);
Is there any solution for this?
UPDATED
Here I have implemented the answer which suggested by @Burak Cakir in the answer. But now I am getting larger image in PDF. For better understanding, Please find the images below. 
The actually Image is
I would suggest you to use iText pdf library. Here is the gradle dependency:
implementation 'com.itextpdf:itextg:5.5.10'
Document document = new Document();
String directoryPath = android.os.Environment.getExternalStorageDirectory().toString();
PdfWriter.getInstance(document, new FileOutputStream(directoryPath + "/example.pdf")); // Change pdf's name.
document.open();
Image image = Image.getInstance(directoryPath + "/" + "example.jpg"); // Change image's name and extension.
float scaler = ((document.getPageSize().getWidth() - document.leftMargin()
- document.rightMargin() - 0) / image.getWidth()) * 100; // 0 means you have no indentation. If you have any, change it.
image.scalePercent(scaler);
image.setAlignment(Image.ALIGN_CENTER | Image.ALIGN_TOP);
document.add(image);
document.close();
Download source code from here (Convert Image to pdf in android programmatically)
MainActivity.java:
package com.deepshikha.convertbitmap;
import android.Manifest;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.pdf.PdfDocument;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Display;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
public static final int GALLERY_PICTURE = 1;
Button btn_select, btn_convert;
ImageView iv_image;
boolean boolean_permission;
boolean boolean_save;
Bitmap bitmap;
public static final int REQUEST_PERMISSIONS = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
listener();
fn_permission();
}
private void init() {
btn_select = (Button) findViewById(R.id.btn_select);
btn_convert = (Button) findViewById(R.id.btn_convert);
iv_image = (ImageView) findViewById(R.id.iv_image);
}
private void listener() {
btn_select.setOnClickListener(this);
btn_convert.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.btn_select:
Intent intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(intent, GALLERY_PICTURE);
break;
case R.id.btn_convert:
if (boolean_save){
Intent intent1=new Intent(getApplicationContext(),PDFViewActivity.class);
startActivity(intent1);
}else {
createPdf();
}
break;
}
}
private void createPdf(){
WindowManager wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
DisplayMetrics displaymetrics = new DisplayMetrics();
this.getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
float hight = displaymetrics.heightPixels ;
float width = displaymetrics.widthPixels ;
int convertHighet = (int) hight, convertWidth = (int) width;
// Resources mResources = getResources();
// Bitmap bitmap = BitmapFactory.decodeResource(mResources, R.drawable.screenshot);
PdfDocument document = new PdfDocument();
PdfDocument.PageInfo pageInfo = new PdfDocument.PageInfo.Builder(bitmap.getWidth(), bitmap.getHeight(), 1).create();
PdfDocument.Page page = document.startPage(pageInfo);
Canvas canvas = page.getCanvas();
Paint paint = new Paint();
paint.setColor(Color.parseColor("#ffffff"));
canvas.drawPaint(paint);
bitmap = Bitmap.createScaledBitmap(bitmap, bitmap.getWidth(), bitmap.getHeight(), true);
paint.setColor(Color.BLUE);
canvas.drawBitmap(bitmap, 0, 0 , null);
document.finishPage(page);
// write the document content
String targetPdf = "/sdcard/test.pdf";
File filePath = new File(targetPdf);
try {
document.writeTo(new FileOutputStream(filePath));
btn_convert.setText("Check PDF");
boolean_save=true;
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(this, "Something wrong: " + e.toString(), Toast.LENGTH_LONG).show();
}
// close the document
document.close();
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == GALLERY_PICTURE && resultCode == RESULT_OK) {
if (resultCode == RESULT_OK) {
Uri selectedImage = data.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(
selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex);
cursor.close();
bitmap = BitmapFactory.decodeFile(filePath);
iv_image.setImageBitmap(bitmap);
btn_convert.setClickable(true);
}
}
}
private void fn_permission() {
if ((ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED)||
(ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED)) {
if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, android.Manifest.permission.READ_EXTERNAL_STORAGE))) {
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE},
REQUEST_PERMISSIONS);
}
if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE))) {
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_PERMISSIONS);
}
} else {
boolean_permission = true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == REQUEST_PERMISSIONS) {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
boolean_permission = true;
} else {
Toast.makeText(getApplicationContext(), "Please allow the permission", Toast.LENGTH_LONG).show();
}
}
}
}
Thanks!
By using this code you can convert image to pdf file.
import java.io.*;
import com.lowagie.text.*;
import com.lowagie.text.pdf.*;
public class imagesPDF
{
public static void main(String arg[])throws Exception
{
Document document=new Document();
PdfWriter.getInstance(document,new FileOutputStream("YourPDFHere.pdf"));
document.open();
Image image = Image.getInstance ("yourImageHere.jpg");
document.add(new Paragraph("Your Heading for the Image Goes Here"));
document.add(image);
document.close();
}
}
For image to PDF there are may libraries available like iText, droidtext so you can use it.
You can convert a JPG to a PDF by targeting a minimum SDK of 19 (KitKat 4.4) and using Google's PdfDocument API ( https://developer.android.com/reference/android/graphics/pdf/PdfDocument ), as shown below in Kotlin:
// Load JPG file into bitmap
val f: File = myJPGFile
val bitmap: Bitmap = BitmapFactory.decodeFile(f.absolutePath)
// Create a PdfDocument with a page of the same size as the image
val document: PdfDocument = PdfDocument()
val pageInfo: PdfDocument.PageInfo = PdfDocument.PageInfo.Builder(bitmap.width, bitmap.height, 1).create()
val page: PdfDocument.Page = document.startPage(pageInfo)
// Draw the bitmap onto the page
val canvas: Canvas = page.canvas
canvas.drawBitmap(bitmap, 0f, 0f, null)
document.finishPage(page)
// Write the PDF file to a file
val directoryPath: String = android.os.Environment.getExternalStorageDirectory().toString()
document.writeTo( FileOutputStream(directoryPath + "/example.pdf"))
document.close()
来源：https://stackoverflow.com/questions/36305362/how-to-convert-image-to-pdf