If no callback is registered (part **) this code works fine.
But there is no sound when the callback function is registered.
I would like to register a play callback to preprocess the streamed data.
How to register a callback function can be found by looking at the python-vlc documentation.
But I can't figure out how to write the callback function.
The second argument to the callback function, samples, is a pointer to the data to be played.
How should I write a callback function at the (*) part with this pointer?
Any reply would be appreciated.
And log file is here. https://gist.github.com/metamath1/7c4f6 ... a8cca9c653
Code: Select all
import vlc
import re
import requests
import ctypes
url = "http://serpent0.duckdns.org:8088/kbsfm.pls"
res = requests.get(url)
res.raise_for_status()
# retrieve url
p = re.compile("https://.+")
m = p.search(res.text)
url = m.group()
# AudioPlayCb = ctypes.CFUNCTYPE(None, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_uint, ctypes.c_int64)
@vlc.CallbackDecorators.AudioPlayCb
def play_callback(data, samples, count, pts):
bytes_read = count * 4 * 2
buffer_array = ctypes.cast(samples, ctypes.POINTER(ctypes.c_char * bytes_read))
##################################################################################
# THIS CODE IS INVALID. TO DO IT RIGHT, WHERE SHOULD BUFFER_ARRAY BE COPIED TO? (*)
buffer = bytearray(bytes_read)
buffer[:] = buffer_array.contents
##################################################################################
instance = vlc.Instance(["--prefetch-buffer-size=2000 --prefetch-read-size=5000 --network-caching=1000"]) #define VLC instance
media = instance.media_new(url)
player = media.player_new_from_media()
player.audio_set_format("f32l", 48000, 2)
# PLAYS WELL WITHOUT THIS LINE (**)
player.audio_set_callbacks(play=play_callback, pause=None, resume=None, flush=None, drain=None, opaque=None)
player.play() #Play the media
c = input()