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Convert PDF to BMP

JPedal provides several methods to allow easy conversion of a PDF file or directory of PDF files into BMP. Java examples use the BmpEncoderOptions classes.

Convert PDF to BMP from Command Line or another language

java -jar jpedal.jar --convert "inputFileOrDir" "outputDir" bmp

Convert PDF to BMP in Java with convenience static method

ConvertPagesToImages.
writeAllPagesAsImagesToDir("inputFileOrDir", "outputDir" , "bmp", 1.33f);

Convert PDF to BMP in Java with control over the image output

ConvertPagesToImages convert = new ConvertPagesToImages("/path/to/file.pdf");
if (convert.openPDFFile()) {
    try {
        for (int page = 1; page <= convert.getPageCount(); page++) {
            BufferedImage bi = convert.getPageAsImage(page);
            File out = new File("/path/to/output/" + page + ".bmp");
            //setters to control output
            final BmpEncoderOptions options = new BmpEncoderOptions();
            JDeli.write(bi, options, out);           
        }
    } catch (PdfException | IOException e) {
        e.printStackTrace();
    } 
}
convert.closePDFfile();

Convert PDF to BMP in Java with a password-protected PDF file

ConvertPagesToImages convert = new ConvertPagesToImages("/path/to/file.pdf");
convert.setPassword("password"); 
if (convert.openPDFFile()) {
    try {
        for (int page = 1; page <= convert.getPageCount(); page++) {
            BufferedImage bi = convert.getPageAsImage(page);
            File out = new File("/path/to/output/" + page + ".bmp");
            JDeli.write(bi, OutputFormat.BMP, out);           
        }
    } catch (PdfException | IOException e) {
        e.printStackTrace();
    } 
}
convert.closePDFfile();

If you are looking for upscaling or more complex control over the PDF to BMP conversion, ConvertPagesToHiResImages class has lots of additional options