Thursday, May 7, 2015

Controlling VLC via Python and some AHK

I've got an Arduino with an LCD. Previously I developed a Python application which connected via serial and showed songs playing and let me change the track and volume through the magic of CMUS. CMUS is a wonderful music program, for *NIX systems. If you are trapped in a Windows environment you might use VLC. With CMUS you can connect via "cmus-remote" and query the tracks accessing the necessary information. With VLC no such feature is available. I was able to get my display information by looking at the window titles using a modification of the post on StackOverflow:

I've put it in a function and modified it slightly from the post.

def getWindowsTitles():
    EnumWindows = ctypes.windll.user32.EnumWindows
    EnumWindowsProc = ctypes.WINFUNCTYPE(ctypes.c_bool, ctypes.POINTER(ctypes.c_int), ctypes.POINTER(ctypes.c_int))
    GetWindowText = ctypes.windll.user32.GetWindowTextW
    GetWindowTextLength = ctypes.windll.user32.GetWindowTextLengthW
    IsWindowVisible = ctypes.windll.user32.IsWindowVisible
    titles = []
    def foreach_window(hwnd, lParam):
        if IsWindowVisible(hwnd):
            length = GetWindowTextLength(hwnd)
            buff = ctypes.create_unicode_buffer(length + 1)
            GetWindowText(hwnd, buff, length + 1)
        return True
    EnumWindows(EnumWindowsProc(foreach_window), 0)
    return titles

This works fine for reading the Artist and Song if one is playing, but that doesn't let us change the track.

I tried several things to send input to VLC, but to no avail. Several input libraries wouldn't work, and I finally tried AutoHotKey. The Python Package which hooks in didn't seem to work with the current DLL, so I just made exes from the AHK scripts:

Example Next Track:

SetTitleMatchMode, RegEx
IfWinExist .*VLC media player

Sleep 1000
Send {Alt down}{l}
Sleep 100
Send {x}
Send {Alt up}

There are probably better ways of getting it work, but for now I'm content with this implementation.

Tuesday, May 5, 2015

Windows Host to Linux Guest Named Pipe on VirtualBox

It is fairly simple just open settings:

Then you can connect via PUTTY on Windows and cat to or from /dev/ttyS0 and see the results.

Friday, May 1, 2015

Arduino LCD Shield

Replacement Resistors

A while back my LCD Shield had an incident in my backpack and the blue contrast adjustment snapped off. I couldn't find it, it must have walked off. I was set to order a new one.  Ordered a new one from China, but I found the old broken screen and didn't have a replacement part, but I did have resistors. I found the perfect  a usable setting:
Fixed Contrast Replacement

I guess I'll have a spare once my other one gets in, but I was happy I made this one work again.