AO2XP/audio.py

# platform-dependent audio module using BASS

import platform, ctypes, os
from pybass import constants_only as ctts
import ini

DOWNLOADPROC = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.c_void_p, ctypes.c_ulong, ctypes.c_void_p)

dll = None
dllf = ""
opus = ""
use_ctypes = False
if platform.system() == "Windows":
    dllf = "bass.dll"
    opus = "bassopus.dll"
elif platform.system() == "Darwin":
    dllf = "libbass.dylib"
    opus = "libbassopus.dylib"
else:
    dllf = "libbass.so"
    opus = "libbassopus.so"

def checkAvailable():
    """
Check if the DLLs exist
Returns string with dll name if it's missing, empty if all DLLs are in place
    """
    one = os.path.exists(os.path.abspath(dllf))
    two = os.path.exists(os.path.abspath(opus))
    if not one: return dllf
    if not two: return two
    return ""



def init(freq=48000):
    """
Initialize BASS and the opus plugin
    """
    global dll, use_ctypes
    if platform.system() == "Darwin":
        dll = ctypes.CDLL(dllf)
        use_ctypes = True
    else:
        import pybass as dll

    dll.BASS_Free()
    dll.BASS_Init(ini.read_ini_int("AO2XP.ini", "Audio", "device", -1), freq, 0, 0, 0)
    dll.BASS_PluginLoad(os.path.abspath(opus), 0)

def free():
    """
Free BASS
    """
    dll.BASS_Free()

def getcurrdevice():
    return dll.BASS_GetDevice()

def getdevices():
    """
Get BASS devices
    """
    info = ctts.BASS_DEVICEINFO() if use_ctypes else dll.BASS_DEVICEINFO()
    ind = 0
    devices = []
    while dll.BASS_GetDeviceInfo(ind, ctypes.addressof(info) if use_ctypes else info):
        devices.append(info.name)
        ind += 1
    return devices

def loadhandle(mem, file, offset=0, length=0, flags=0):
    """
Load a BASS stream handle
    """
    return dll.BASS_StreamCreateFile(mem, file, ctts.QWORD(offset), ctts.QWORD(length), flags)

def loadURLhandle(url, offset, flags, proc=DOWNLOADPROC(), user=0):
    """
Load a BASS stream handle from an URL
    """
    return dll.BASS_StreamCreateURL(url, offset, flags, proc, user)

def freehandle(handle):
    """
Free a handle
    """
    return dll.BASS_StreamFree(handle)

def playhandle(handle, restart):
    """
Play a handle
    """
    return dll.BASS_ChannelPlay(handle, restart)

def stophandle(handle):
    """
Stop handle playback
    """
    return dll.BASS_ChannelStop(handle)

def handleisactive(handle):
    """
Get handle playback status
    """
    return dll.BASS_ChannelIsActive(handle)

def sethandleattr(handle, attr, value):
    """
Set handle attribute
    """
    if use_ctypes and type(value) == float: value = ctypes.c_float(value)
    return dll.BASS_ChannelSetAttribute(handle, attr, value)