Page embedded thumbnail

Returns the bytes of a page's embedded /Thumb image stream, if the PDF carries one. PDF authoring tools sometimes embed a low-resolution preview alongside each page; readers can display that thumbnail without rendering the full page. Wraps FPDFPage_GetRawThumbnailData and FPDFPage_GetDecodedThumbnailData.

Usage

pdf_page_thumbnail(page, page_num = 1L, decoded = TRUE)

Arguments

page

A pdfium_page from pdf_page_load(), or a pdfium_doc.

page_num

One-based page index. Only used when page is a pdfium_doc. Ignored otherwise.

decoded

If TRUE (default) returns the decoded bitmap bytes after PDFium has applied any stream filter (e.g. /FlateDecode). If FALSE, returns the raw filtered bytes — useful when a caller wants to save the thumbnail back to disk in its original encoded form, or pipe it through a different decoder.

Value

A raw vector. Length zero when the page has no /Thumb.

Details

Most PDFs produced by Cairo, LaTeX, or web tools do not embed thumbnails — this function returns raw(0) in that common case.

See also

pdf_render_page() to rasterize the full page instead.