A NixOS module for loading and configuring the v4l2loopback kernel module

[srec] / srec.py

diff --git a/srec.py b/srec.py
index d57cde2b3b7e2c2e6dc003f43cfc5574f968d2dd..bacc1df5654fbffd2c8a8b4765abcc87e420f0b8 100644 (file)
--- a/srec.py
+++ b/srec.py
@@ -8,11 +8,14 @@ from dataclasses import dataclass
 from datetime import datetime
 import os
 import subprocess
-from typing import Callable
+from typing import Any, Callable
 
 import gi
 gi.require_version("Gtk", "4.0")
-from gi.repository import Gtk  # nopep8 pylint: disable=wrong-import-position
+gi.require_version("GLib", "2.0")
+
+from gi.repository import Gtk   # nopep8 pylint: disable=wrong-import-position
+from gi.repository import GLib  # nopep8 pylint: disable=wrong-import-position
 
 
 @dataclass
@@ -27,22 +30,51 @@ recording: Recording | None = None
 def make_filename() -> str:
     directory = os.environ.get(
         'XDG_VIDEOS_DIR',
-        os.path.expanduser('~/Videos'))
+        os.path.expanduser('~/Videos/SRec'))
     os.makedirs(directory, exist_ok=True)
     timestamp = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
     return os.path.join(directory, f'srec {timestamp}.mkv')
 
 
+def video_source(stack: Gtk.Stack) -> list[str]:
+    if stack.get_child_by_name('not_recording').get_first_child().get_active():
+        return ['-f', 'x11grab', '-i', ':0.0+0,0']
+    return ['-f', 'v4l2', '-i', '/dev/video0']
+
+
+def find_size_display(stack: Gtk.Stack) -> Gtk.Label:
+    return stack.get_child_by_name(
+        'recording').get_first_child().get_next_sibling()
+
+
+def summarize_size(n: int) -> str:
+    if n > 100_000_000:
+        m = int(n / (1024 * 1024))
+        return f'{m}M'
+    if n > 100_000:
+        k = int(n / 1024)
+        return f'{k}K'
+    return str(n)
+
+
 def on_start_recording(_: Gtk.Button, stack: Gtk.Stack) -> None:
     global recording  # pylint: disable=global-statement
     assert recording is None
+
     filename = make_filename()
-    command = [
-            'ffmpeg',
-            '-framerate', '25',
-            '-f', 'x11grab', '-i', ':0.0+0,0',
-            '-f', 'pulse', '-ac', '2', '-i', 'default',
-            filename]  # nopep8
+    size_display = find_size_display(stack)
+
+    def update_size_display() -> Any:
+        try:
+            size = summarize_size(os.stat(filename).st_size)
+        except FileNotFoundError:
+            size = '--'
+        size_display.set_label(f'<big>{size}</big>')
+        return GLib.SOURCE_REMOVE if recording is None else GLib.SOURCE_CONTINUE
+    GLib.timeout_add_seconds(1, update_size_display)
+
+    command = (['ffmpeg', '-framerate', '25'] + video_source(stack) +
+               ['-f', 'pulse', '-ac', '2', '-i', 'default', filename])
     # pylint: disable=consider-using-with
     recording = Recording(
         filename=filename,
@@ -73,19 +105,35 @@ def make_button(label: str, action: Callable[[
     return button
 
 
+def make_share_control() -> Gtk.CheckButton:
+    can_share = os.path.exists('/sys/module/v4l2looback')
+    control = Gtk.CheckButton(
+        label='Share Webcam', sensitive=can_share, active=can_share)
+    control.set_margin_start(20)
+    return control
+
+
 def on_activate(app: Gtk.Application) -> None:
     win = Gtk.ApplicationWindow(application=app)
     win.set_title('SRec')
-    stack = Gtk.Stack()
+    win.set_icon_name('srec')
 
-    start_recording = make_button("Start Recording", on_start_recording, stack)
-    stack.add_named(start_recording, "not_recording")
+    stack = Gtk.Stack()
 
-    box = Gtk.Box()
-    box.set_orientation(Gtk.Orientation.VERTICAL)
-    stop_recording = make_button("Stop Recording", on_stop_recording, stack)
-    box.append(stop_recording)
-    stack.add_named(box, "recording")
+    nr_box = Gtk.Box()
+    nr_box.set_orientation(Gtk.Orientation.VERTICAL)
+    screen = Gtk.CheckButton(label='Screen')
+    nr_box.append(screen)
+    nr_box.append(Gtk.CheckButton(label='Webcam', active=True, group=screen))
+    nr_box.append(make_share_control())
+    nr_box.append(make_button("Start Recording", on_start_recording, stack))
+    stack.add_named(nr_box, "not_recording")
+
+    r_box = Gtk.Box()
+    r_box.set_orientation(Gtk.Orientation.VERTICAL)
+    r_box.append(make_button("Stop Recording", on_stop_recording, stack))
+    r_box.append(Gtk.Label(use_markup=True, justify=Gtk.Justification.CENTER))
+    stack.add_named(r_box, "recording")
 
     win.set_child(stack)
     win.present()