在Ruby Search PDF中，突出显示找到的文本，导出页面的JPG

Question

我想查看是否有人这样做。

在ruby中，我想打开PDF并在那里搜索文本。我找到的任何文本都想用黄色突出显示，然后返回发现文本为jpg的页面。有没有人做过这个？

谢谢， 克雷格

Answer 1

如果你乐于使用C的扩展，你可以用红宝石实现这一目标-gnome2绑定。你需要poppler和gdk_pixbuf2宝石。

这些宝石的API文档是有点吝啬，但你可以找到什么有在http://ruby-gnome2.sourceforge.jp/

require 'poppler' 
require 'gdk_pixbuf2' 

SCALE = 2 

filename = "source.pdf" 
doc = Poppler::Document.new(filename) 
page = doc.get_page(0) 

# render the page to an in-memory buffer 
width, height = *page.size 
buf = Gdk::Pixbuf.new(Gdk::Pixbuf::COLORSPACE_RGB, true, 8, width*SCALE, height*SCALE) 
page.render(0, 0, width*SCALE, height*SCALE, SCALE, 0, buf) 

# copy the rendered buffer into an pixmap for further editing 
map = Gdk::Pixmap.new(nil, width*SCALE, height*SCALE, 24) 
map.draw_pixbuf(nil, buf, 0, 0, 0, 0, -1, -1, Gdk::RGB::DITHER_NONE, 0, 0) 

# setup highlight color and blend function 
gc = Gdk::GC.new(map) # graphics context 
gc.rgb_fg_color = Gdk::Color.new(65535, 65535, 0) 
gc.function = Gdk::GC::AND 

# find each match and highlight it. The co-ordinate maths is ugly but 
# necesary to convert from PDF co-ords to Pixmap co-ords 
page.find_text("the").each do |match| 
    matchx = match.x1 * SCALE 
    matchy = (height - match.y2) * SCALE 
    matchw = (match.x2-match.x1) * SCALE 
    matchh = (match.y2-match.y1) * SCALE 
    map.draw_rectangle(gc, true, matchx, matchy, matchw, matchh) 
end 

# save the buffer to a JPG 
newbuf = Gdk::Pixbuf.from_drawable(nil, map, 0, 0, width*SCALE, height*SCALE) 
newbuf.save("foo.jpg", "jpeg") 

Answer 2

是，JRuby或致电通过命令行选项的罐子？在这种情况下，你可以使用Java iText库和沿东西这些答案的线

iText Search, Highlight, image of result

Is it possible to find text position with iText