Page Devices
This guide shows how to render PDF pages to image files using BmpDevice and
PdfPageRenderer in Aspose.PDF FOSS for Java. You will learn to generate BMP
thumbnails and use page rendering for image-based processing pipelines.
BmpDevice
BmpDevice renders a PDF page to a BMP image file. This is useful for generating
thumbnails, document previews, and image-based pipelines. Call process(page, path)
with a Page instance and an output file path to produce the BMP file.
try (Document doc = new Document("input.pdf")) {
BmpDevice device = new BmpDevice();
PageCollection pages = doc.getPages();
Page page = pages.get(1);
device.process(page, "page1.bmp");
}The output is a standard BMP file that can be further processed with standard Java
image libraries such as javax.imageio.
PdfPageRenderer
PdfPageRenderer renders PDF pages to image output. Use PdfPageRenderer when you
need rendering output beyond what BmpDevice provides directly.
Use Cases
- Thumbnail generation — render the first page of each document as a preview image
- Document preview — display a specific page in an image viewer
- Image pipelines — pass rendered page images to OCR or image analysis tools
- Batch preview — iterate all pages and render each to a separate file
try (Document doc = new Document("input.pdf")) {
BmpDevice device = new BmpDevice();
PageCollection pages = doc.getPages();
for (int i = 1; i <= pages.getCount(); i++) {
Page page = pages.get(i);
device.process(page, "page" + i + ".bmp");
}
}