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| #! /usr/bin/env python3 | |
| # | |
| # GlSurface example code for VLC Python bindings | |
| # Copyright (C) 2020 Daniël van Adrichem <daniel5gh@spiet.nl> | |
| # | |
| # This program is free software; you can redistribute it and/or modify | |
| # it under the terms of the GNU General Public License as published by | |
| # the Free Software Foundation; either version 2 of the License, or | |
| # (at your option) any later version. | |
| # | |
| # This program is distributed in the hope that it will be useful, | |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| # GNU General Public License for more details. | |
| # | |
| # You should have received a copy of the GNU General Public License | |
| # along with this program; if not, write to the Free Software | |
| # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. | |
| # | |
| """VLC GlSurface example | |
| """ | |
| import time | |
| import ctypes | |
| from threading import Lock | |
| import numpy as np | |
| from OpenGL.GL import (GL_TEXTURE_2D, glTexSubImage2D, glTexImage2D, | |
| GL_BGR, GL_RGB, | |
| GL_UNSIGNED_BYTE) | |
| import vlc | |
| class Surface(object): | |
| """A lockable image buffer | |
| """ | |
| def __init__(self, w, h): | |
| self._width = w | |
| self._height = h | |
| # size in bytes when RV32 *4 or RV24 * 3 | |
| self._row_size = self._width * 3 | |
| self._buf_size = self._height * self._row_size | |
| # allocate buffer | |
| self._buf1 = np.zeros(self._buf_size, dtype=np.ubyte) | |
| # get pointer to buffer | |
| self._buf_p = self._buf1.ctypes.data_as(ctypes.c_void_p) | |
| self._lock = Lock() | |
| def update_gl(self): | |
| # with self._lock: | |
| glTexSubImage2D(GL_TEXTURE_2D, | |
| 0, 0, 0, | |
| self._width, | |
| self._height, | |
| GL_BGR, | |
| GL_UNSIGNED_BYTE, | |
| self._buf1) | |
| def create_texture_gl(self): | |
| glTexImage2D(GL_TEXTURE_2D, | |
| 0, | |
| GL_RGB, | |
| self._width, # width | |
| self._height, # height | |
| 0, | |
| GL_BGR, | |
| GL_UNSIGNED_BYTE, | |
| None) | |
| @property | |
| def width(self): | |
| return self._width | |
| @property | |
| def height(self): | |
| return self._height | |
| @property | |
| def row_size(self): | |
| return self._row_size | |
| @property | |
| def buf(self): | |
| return self._buf1 | |
| @property | |
| def buf_pointer(self): | |
| return self._buf_p | |
| def lock(self): | |
| self._lock.acquire() | |
| def unlock(self): | |
| self._lock.release() | |
| def __enter__(self, *args): | |
| return self._lock.__enter__(*args) | |
| def __exit__(self, *args): | |
| return self._lock.__exit__(*args) | |
| def get_libvlc_lock_callback(self): | |
| @vlc.VideoLockCb | |
| def _cb(opaque, planes): | |
| self._lock.acquire() | |
| planes[0] = self._buf_p | |
| return _cb | |
| def get_libvlc_unlock_callback(self): | |
| @vlc.VideoUnlockCb | |
| def _cb(opaque, picta, planes): | |
| self._lock.release() | |
| return _cb | |
| if __name__ == '__main__': | |
| import sys | |
| player = vlc.MediaPlayer(sys.argv[1]) | |
| # play and stop so video_get_size gets a correct value | |
| # setting all callbacks to None prevents a window being created on play | |
| player.video_set_callbacks(None, None, None, None) | |
| # play and stop so video_get_size gets a correct value | |
| player.play() | |
| time.sleep(1) | |
| player.stop() | |
| w, h = player.video_get_size() | |
| surface = Surface(w, h) | |
| # need to keep a reference to the CFUNCTYPEs or else it will get GCed | |
| _lock_cb = surface.get_libvlc_lock_callback() | |
| _unlock_cb = surface.get_libvlc_unlock_callback() | |
| player.video_set_callbacks(_lock_cb, _unlock_cb, None, None) | |
| player.video_set_format( | |
| "RV24", | |
| surface.width, | |
| surface.height, | |
| surface.row_size) | |
| # this starts populating the surface's buf with pixels, from another thread | |
| player.play() | |
| # in main thread, where gl context is current: | |
| # FIXME: add some code to embed the surface + a mainloop | |
| # v.surface.update_gl() |
you could add more example usages I see I used back then:
def screenshot():
try:
from PIL import Image
except ImportError:
_log.critical('need PIL or Pillow for screenshots')
else:
fn = "scrn-{}.png".format(player.get_time())
_log.info(fn)
with surface:
img = Image.frombuffer(
"RGBA",
(surface.width, surface.height),
surface.buf, "raw", "BGRA", 0, 1)
img.save(fn)
return img
def copy_array():
with surface:
copy = surface.buf.copy()
return copy
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Lets go for
class Surface:withoutobjectto set a good example.on line 53
# with self._lock:can be removed.EDIT: actually, I am not sure why I commented this out, logically it should be locked. Maybe it was not strictly needed and I accepted any tearing or other artifacts of half updated buffers in favor of higher update frequency due to no locking.
on line 145, lets make it
surface.update_gl()withoutv. In my original code I have aVideoclass to which thisvwas a reference.I approve including this code snippet in VLC Python bindings using the GNU General Public License