tools: new video module:

this module is really basic at the moment, and use `ffmpeg` if present to make thumbnails.

sat/tools/video.py

@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+
+# SàT: an XMPP client
+# Copyright (C) 2009-2020 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Methods to manipulate videos"""
+from typing import Union
+from pathlib import Path
+from twisted.python.procutils import which
+from sat.core.i18n import _
+from sat.core import exceptions
+from sat.core.log import getLogger
+from .common import async_process
+
+
+log = getLogger(__name__)
+
+
+
+
+
+try:
+    ffmpeg_path = which('ffmpeg')[0]
+except IndexError:
+    log.warning(_(
+        "ffmpeg executable not found, video thumbnails won't be available"))
+    ffmpeg_path = None
+
+
+async def get_thumbnail(video_path: Union[Path, str], dest_path: Path) -> Path:
+    """Extract thumbnail from video
+
+    @param video_path: source of the video
+    @param dest_path: path where the file must be saved
+    @return: path of the generated thumbnail
+        image is created in temporary directory but is not delete automatically
+        it should be deleted after use.
+        Image will be in JPEG format.
+    @raise exceptions.NotFound: ffmpeg is missing
+    """
+    if ffmpeg_path is None:
+        raise exceptions.NotFound(
+            _("ffmpeg executable is not available, can't generate video thumbnail"))
+
+    await async_process.run(
+        ffmpeg_path, "-i", str(video_path), "-ss", "10", "-frames:v", "1", str(dest_path)
+    )