#35 Custom background color

[Anonymous]

for screen reading, the ability to customize the
background color of the doc (override the image-
background layer with a solid grey for example) would
be helpful - the white of most docs is glaring...

[Andrew Zhezherun]

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You can easily change white background to grey using display
adjustment controls. As for changing background color,
there's no such element in DjVu file as "background color",
so it's not easy to change it reliably. For black-and-white
documents, however, one easy way is to just replace the
white color with specified color pixel-wise, but for color
documents it is not that simple.

Andrew

[asewafea]

Build WinDjView with a custom background color:

For example, inside a virtual machine:

Download the WinDjView source code:

Go to https://sourceforge.net/projects/windjview/files/WinDjView/2.1/
Download WinDjView-2.1.tar.bz2. You can use Winrar to unzip it and its contents (it is also an archive) - rename these 2 archives by adding .zip to the files' names.
You'll get the WinDjView-2.1 folder. Put it on the D: partition for example.

Edit the source file to change the background color, and the fullscreen color, from dark grey i.e. RGB(64, 64, 64) and black for fullscreen i.e. RGB(0, 0, 0) to a lighter grey color (R,G,B = 192,192,192)

The edited lines are:

D:\WinDjView-2.1\DjVuView.cpp

COLORREF clrBackground = RGB(192, 192, 192);
if (m_nType == Fullscreen || m_nType == Magnify && GetMainFrame()->IsFullscreenMode())
    clrBackground = RGB(192, 192, 192);

The original text was:

COLORREF clrBackground = RGB(64, 64, 64);
if (m_nType == Fullscreen || m_nType == Magnify && GetMainFrame()->IsFullscreenMode())
    clrBackground = RGB(0, 0, 0);

Save the file.

Install Visual studio 2013

Download Visual Studio 2013 Professional:
https://go.microsoft.com/fwlink/?LinkId=532507&type=ISO&clcid=0x409

(Link with the Visual Studio download locations: https://superuser.com/questions/840295/microsoft-visual-studio-2013-update-4-rtm-iso-offline-installer)
Install it. (I chose to install only the MFC files, but I think it works with all the extra packages deselected). You may need to be connected to the internet and have the installer able to download required installation files.

After installation, restart the computer, just as the installer says.

Go to the source code folder and build the WinDjView executable:

You have to build libdjvu64.lib first:

Open a command prompt with admin privileges.
inside the command prompt go to the folder "D:\WinDjView-2.1\libdjvu":
(e.g.: use
chdir /d D:
cd D:\WinDjView-2.1\libdjvu )

Inside the cmd.exe command prompt, execute make_x64.bat.
Then execute make.bat

Inside cmd.exe go to the parent directory D:\WinDjView-2.1 and build WinDjView by executing the file make_x64.bat.

After the build process is complete, your custom built executable - WinDjView.exe is found inside the folder D:\WinDjView-2.1\Release_x64.

Copy this WinDjView.exe anywhere you like and use it to view .djvu files.