The value of the key type is null but must be xobject. When you create a pdf document your images are normally stored in a compressed format. Pdfsharp stores tiff images using lossless compression. Id like to know which image format and compression was used for the tiff file. The pdf creation process basically chooses between two compression types. Source code here are code snippets for the 4 variations implemented in concatenate documents. Not suitable for line art, but very good for photos. Pdf image quality and compression bullzip knowledge base.
Choose tools optimize pdf or click on the tool from the right hand panel. You can activate some options to generate smaller pdf files at the price of longer creation times. If you reduce the tiff images say 80% or 75% of the original size then you should see a big difference of the file size, but with a loss of quality. If you use the pdfsharp source code, make sure to make all tests with a release build. It does not yet handle jpeg images that have been flateencoded. Those are not supported by this simple sample and require several hours of coding, but this is left as an exercise to the reader.
The jpeg compression is well suited for documents with photos. The image s sample streams computed length 1053150 is different to the actual length 118121. Not sure if the verbose mode can account for a factor 3 i dont expect that. There are several different formats for nonjpeg images in pdf. Free online service to convert a pdf file to a set of optimized jpg images. The value of the key colorspace must not be of type string. Pdfsharpsrcpdfsharp at master empirapdfsharp github. This tool provides better image quality than many other pdf to jpg converters, offers mass conversion and. Pdf output file see the pdf files created by this sample.
Open the optimize pdf tool to compress a pdf document. The most commonly used filter encoder and decoder in pdf is flatedecode. Pdfsharp will optionally apply lz compression to jpeg images, but that usually gains 1 % through 5 % only. Pdf compression in itextsharp, you can use the compressionlevel property of the pdfwriter class to set the compression level of stream objects that are written to the filestream.
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