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mirror of https://github.com/koreader/koreader synced 2024-11-10 01:10:34 +00:00
koreader/frontend/document/djvudocument.lua
chrox 8e4516b824 add regional zoom mode in pdf/djvu page
In regional zoom mode double tap will zoom to the tapped
region(paragraph or column, etc., detected optically via libk2pdfopt).
As the first demo, this feature is only turned on in flipping mode by
tapping the top-left corner of the screen. Eventually we may incorporate
this feature in "free" zoom mode.
2014-01-02 11:14:26 +08:00

120 lines
3.6 KiB
Lua

local Geom = require("ui/geometry")
local Cache = require("cache")
local CacheItem = require("cacheitem")
local KoptOptions = require("ui/data/koptoptions")
local KoptInterface = require("document/koptinterface")
local Document = require("document/document")
local Configurable = require("ui/reader/configurable")
local DrawContext = require("ffi/drawcontext")
local DjvuDocument = Document:new{
_document = false,
-- libdjvulibre manages its own additional cache, default value is hard written in c module.
djvulibre_cache_size = nil,
dc_null = DrawContext.new(),
options = KoptOptions,
koptinterface = KoptInterface,
}
-- check DjVu magic string to validate
local function validDjvuFile(filename)
f = io.open(filename, "r")
if not f then return false end
local magic = f:read(8)
f:close()
if not magic or magic ~= "AT&TFORM" then return false end
return true
end
function DjvuDocument:init()
require "libs/libkoreader-djvu"
self.configurable:loadDefaults(self.options)
if not validDjvuFile(self.file) then
self.error_message = "Not a valid DjVu file"
return
end
local ok
ok, self._document = pcall(djvu.openDocument, self.file, self.djvulibre_cache_size)
if not ok then
self.error_message = self.doc -- will contain error message
return
end
self.is_open = true
self.info.has_pages = true
self.info.configurable = true
self:_readMetadata()
end
function DjvuDocument:invertTextYAxel(pageno, text_table)
local _, height = self.doc:getOriginalPageSize(pageno)
for _,text in pairs(text_table) do
for _,line in ipairs(text) do
line.y0, line.y1 = (height - line.y1), (height - line.y0)
end
end
return text_table
end
function DjvuDocument:getPageTextBoxes(pageno)
return self._document:getPageText(pageno)
end
function DjvuDocument:getWordFromPosition(spos)
return self.koptinterface:getWordFromPosition(self, spos)
end
function DjvuDocument:getTextFromPositions(spos0, spos1)
return self.koptinterface:getTextFromPositions(self, spos0, spos1)
end
function DjvuDocument:getPageBoxesFromPositions(pageno, ppos0, ppos1)
return self.koptinterface:getPageBoxesFromPositions(self, pageno, ppos0, ppos1)
end
function DjvuDocument:getOCRWord(pageno, wbox)
return self.koptinterface:getOCRWord(self, pageno, wbox)
end
function DjvuDocument:getOCRText(pageno, tboxes)
return self.koptinterface:getOCRText(self, pageno, tboxes)
end
function DjvuDocument:getPageRegions(pageno)
return self.koptinterface:getPageRegions(self, pageno)
end
function DjvuDocument:getUsedBBox(pageno)
-- djvu does not support usedbbox, so fake it.
local used = {}
local native_dim = self:getNativePageDimensions(pageno)
used.x0, used.y0, used.x1, used.y1 = 0, 0, native_dim.w, native_dim.h
return used
end
function DjvuDocument:getPageBBox(pageno)
return self.koptinterface:getPageBBox(self, pageno)
end
function DjvuDocument:getPageDimensions(pageno, zoom, rotation)
return self.koptinterface:getPageDimensions(self, pageno, zoom, rotation)
end
function DjvuDocument:renderPage(pageno, rect, zoom, rotation, gamma, render_mode)
return self.koptinterface:renderPage(self, pageno, rect, zoom, rotation, gamma, render_mode)
end
function DjvuDocument:hintPage(pageno, zoom, rotation, gamma, render_mode)
return self.koptinterface:hintPage(self, pageno, zoom, rotation, gamma, render_mode)
end
function DjvuDocument:drawPage(target, x, y, rect, pageno, zoom, rotation, gamma, render_mode)
return self.koptinterface:drawPage(self, target, x, y, rect, pageno, zoom, rotation, gamma, render_mode)
end
function DjvuDocument:register(registry)
registry:addProvider("djvu", "application/djvu", self)
end
return DjvuDocument