为什么pdftoppm poppler-utils没有jpeg选项? [英] Why does pdftoppm poppler-utils have no jpeg option?

问题描述

在Ubuntu 10.04上，我安装了poppler-utils软件包以能够运行pdftoppm.

On Ubuntu 10.04, I've installed the poppler-utils package to be able to run pdftoppm.

我的目标是将PDF转换为jpeg，但是我没有该选项/标志.我似乎唯一拥有的光栅化器是PNG支持.

My goal is to convert PDFs to jpegs, however I don't have that option/flag available. The only rasterizer I seem to have is PNG support.

有人可以建议我如何获得jpeg支持吗?非常感谢.

Could someone please advise how I can get jpeg support? Many thanks.

(运行后，请参见下面的我的选项列表:pdftoppm --help):

(See my options list below after running: pdftoppm --help):

pdftoppm version 0.12.4
Copyright 2005-2009 The Poppler Developers - http://poppler.freedesktop.org
Copyright 1996-2004 Glyph & Cog, LLC
Usage: pdftoppm [options] [PDF-file [PPM-file-prefix]]
  -f <int>            : first page to print
  -l <int>            : last page to print
  -r <fp>             : resolution, in DPI (default is 150)
  -rx <fp>            : X resolution, in DPI (default is 150)
  -ry <fp>            : Y resolution, in DPI (default is 150)
  -scale-to <int>     : scales each page to fit within scale-to*scale-to pixel box
  -scale-to-x <int>   : scales each page horizontally to fit in scale-to-x pixels
  -scale-to-y <int>   : scales each page vertically to fit in scale-to-y pixels
  -x <int>            : x-coordinate of the crop area top left corner
  -y <int>            : y-coordinate of the crop area top left corner
  -W <int>            : width of crop area in pixels (default is 0)
  -H <int>            : height of crop area in pixels (default is 0)
  -sz <int>           : size of crop square in pixels (sets W and H)
  -cropbox            : use the crop box rather than media box
  -mono               : generate a monochrome PBM file
  -gray               : generate a grayscale PGM file
  -png                : generate a PNG file
  -freetype <string>  : enable FreeType font rasterizer: yes, no
  -aa <string>        : enable font anti-aliasing: yes, no
  -aaVector <string>  : enable vector anti-aliasing: yes, no
  -opw <string>       : owner password (for encrypted files)
  -upw <string>       : user password (for encrypted files)
  -q                  : don't print any messages or errors
  -v                  : print copyright and version info
  -h                  : print usage information
  -help               : print usage information
  --help              : print usage information
  -?                  : print usage information

推荐答案

根据此页面应该可以使用选项-jpeg生成jpeg图像作为结果. 如果不能的话，如果允许的话，也许应该获得较新的版本.

According to this page it should be possible to use the option -jpeg to generate a jpeg image as result. If you can't you should get a newer version maybe, if you are allowed to.

如果不是唯一的解决方案，那就是在以后进行转换. 但是无论如何，如果您觉得JPEG转换太慢，我建议您使用 libjpeg-turbo .如果替换标准的libjpeg库，则性能至少应提高2倍.

If not the only solution is to convert it afterwards. But in any way, if you are having the feeling that the JPEG conversion is too slow, I'd give you the advise to use libjpeg-turbo. If you replace the standard libjpeg library you should get a performance boost of the factor 2 at least.

这篇关于为什么pdftoppm poppler-utils没有jpeg选项?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！