> On 29 Jun 2015, at 07:00, Kirk, Kenneth <[email protected]> wrote: > > Well after checking further I found that the problem was in the scaling after > the image was created. I wanting to scale it to 200 dpi using ImageIO and > that is where the size discrepancy came about. If I leave it at 72 dpi it's > okay. One other problem I having is generating a image from a PDF page with > lines that are light gray. When rendering the page as ImageType.BINARY the > lines drops them out completely when the image rendered. I have to render it > as RBG first and make an extra call to convert to black and white which slow > the process way down. It seems the threshold value need to be manipulated > but I'm not sure where one changes that at.
If grayscale would do, then use that instead. If you really do need a binary image then you'll get a better result by rendering in color or grayscale and then thresholding the image yourself. You'll also get better results if you render at a higher DPI (4x, 8x, 16x) and scale down the image with a high-quality algorithm such as Lanczos. -- John > -----Original Message----- > From: Tilman Hausherr [mailto:[email protected]] > Sent: Friday, June 26, 2015 3:51 PM > To: [email protected] > Subject: Re: image Resolution > > Why not just use the dpi parameter when rendering? > > Tilman > >> Am 26.06.2015 um 21:43 schrieb Kirk, Kenneth: >> I'm sure this question has been asked before but I wasn't on the list when >> it was. I have PDFs that I need to convert to images. Most are 8.5x11. >> Some are 8.5 x 3.5. My problem is figuring out the resolution when I save >> them as 200dpi tiff images. I made some assumptions that held true until I >> encountered PDFs that deviated from the those assumptions. Although I can >> assume all PDFs are 8.5 inch wide and therefore I can deduce the resolution >> based of the width of the actually page I don't want to assume anything but >> calculate the resolution base on what I can get from the PDF structure >> itself. >> >> >> >> >> >> >> >> >> ************************************************ >> Disclaimer - This email and any files transmitted with it are confidential >> and contain privileged or copyright information. You must not present this >> message to another party without gaining permission from the sender. If you >> are not the intended recipient you must not copy, distribute or use this >> email or the information contained in it for any purpose other than to >> notify the Office of the Illinois Secretary of State. >> >> If you have received this message in error, please notify the sender >> immediately, and delete this email from your system. Any views expressed in >> this message are those of the individual sender, except where the sender >> specifically states them to be the views of the Office of the Illinois >> Secretary of State. >> ************************************************ > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > > > > > > > > > > ************************************************ > Disclaimer - This email and any files transmitted with it are confidential > and contain privileged or copyright information. You must not present this > message to another party without gaining permission from the sender. If you > are not the intended recipient you must not copy, distribute or use this > email or the information contained in it for any purpose other than to notify > the Office of the Illinois Secretary of State. > > If you have received this message in error, please notify the sender > immediately, and delete this email from your system. Any views expressed in > this message are those of the individual sender, except where the sender > specifically states them to be the views of the Office of the Illinois > Secretary of State. > ************************************************ > > > > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
