Android PdfDocument too big (page dimensions)

I generate a simple PDF with an image (banner) and a title in code as follows:

    public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Bitmap headerBmp = BitmapFactory.decodeResource(getResources(), R.drawable.headerimage);
        PdfDocument pdfDocument = new PdfDocument();
        PdfDocument.PageInfo mypageInfo = new PdfDocument.PageInfo.Builder(2480, 3508, 1).create();
        PdfDocument.Page myPage = pdfDocument.startPage(mypageInfo);
        Canvas canvas = myPage.getCanvas();
        canvas.setDensity(300);

        canvas.drawBitmap(headerBmp, 50, 50, new Paint());
        Paint titlePaint = new Paint();

        titlePaint.setTypeface(Typeface.create(Typeface.DEFAULT, Typeface.BOLD));
        titlePaint.setTextSize(75);
        canvas.drawText("Title", 50, 250, titlePaint);
        pdfDocument.finishPage(myPage);
        File pdfPath = new File(getFilesDir(), "pdf");
        if (!pdfPath.exists()) {
            pdfPath.mkdir();
        }
        File pdfFile = new File(pdfPath, "document.pdf");

        try {

            pdfDocument.writeTo(new FileOutputStream(pdfFile, false));

        } catch (IOException e) {
            // below line is used
            // to handle error
            e.printStackTrace();
        } finally {


            // after storing our pdf to that
            // location we are closing our PDF file.
            pdfDocument.close();

        }
    }
}

The resulting Pdf document is too big (page size). It should fit A4 page size. The document size seems correct when I change this line

PdfDocument.PageInfo mypageInfo = new PdfDocument.PageInfo.Builder(2480, 3508, 1).create();

to this:

PdfDocument.PageInfo mypageInfo = new PdfDocument.PageInfo.Builder(595, 842, 1).create();

But now the image (about 1200 x 300) does not fit the page. If resized to 595 px width the image looks very bad.

2480 x 3508 is the correct size for A4 with 300 dpi 595 x 842 is the correct size for A4 with 72 dpi

But images normally have 300dpi.

How do I make the page fit without loosing image quality?

from Android PdfDocument too big (page dimensions)