Display first page of PDF as Image

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攒了一身酷
攒了一身酷 2021-02-01 10:03

I am creating web application where I am displaying images/ pdf in thumbnail format. Onclicking respective image/ pdf it get open in new window.

For PDF, I have (this is

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  •  耶瑟儿~
    2021-02-01 10:36

    I'm not sure if all browsers display your embedded PDF (done via ) equally well.

    Extracting 1st Page as PDF

    If you insist on using PDF, I'd recommend one of these 2 commandline tools to extract the first page of any PDF:

    1. pdftk
    2. Ghostscript

    Both are available for Linux, Mac OS X and Windows.

    pdftk command

    pdftk input.pdf cat 1 output page-1-of-input.pdf
    

    Ghostscript command

    gs -o page-1-of-input.pdf -sDEVICE=pdfwrite -dPDFLastPage=1 input.pdf
    

    (On Windows use gswin32c.exe or gswin64c.exe instead of gs.)

    pdftk is slightly faster than Ghostscript when it comes to page extraction, but for a single page that difference is probably neglectable. As of the most recent released version, v9.05, the previous sentence is no longer true. I found that Ghostscript (including all startup overhead) requires ~1 second to extract the 1st page from the 756 page PDF specification, while PDFTK needed ~11 seconds.

    Converting 1st Page to JPEG

    If you want to be sure that even older browsers can display your 1st page well, then convert it to JPEG. Ghostscript is your friend here (ImageMagick cannot do it by itself, it needs the help of Ghostscript anyway):

    gs -o page-1-of-input-PDF.jpeg -sDEVICE=jpeg -dLastPage=1 input.pdf
    

    Should you need page 33, you can do it like this:

    gs -o page-33-of-input-PDF.jpeg -sDEVICE=jpeg -dFirstPage=33 -dLastPage33 input.pdf
    

    If you need a range of PDFs, like pages 17-23, try this:

    gs -o page-16+%03d-of-input-PDF.jpeg -sDEVICE=jpeg -dFirstPage=17 -dLastPage23 input.pdf
    

    Note, that the %03d notation increments with each page processed, starting with 1. So your first JPEG's name would be page-16+001-of-input-PDF.jpeg.

    Maybe PNG is better?

    Be aware that JPEG isn't a format suited well for images containing high black+white contrast and sharp edges like text pages. PNG is much better for this.

    To create a PNG from the 1st PDF pages with Ghostscript is easy:

    gs -o page-1-of-input-PDF.png -sDEVICE=pngalpha -dLastPage=1 input.pdf
    

    The analog options as with JPEGs are true when it comes to extract ranges of pages.

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