Lets a user transmit a second hardware input device (e.g. line-in / aux)
alongside the mic, with its own device picker and volume, from Audio Settings.
No core/ABI/proto changes: the aux is a VC_STREAM_AUX_DEVICE stream started
with external_feed=1 and fed via vc_stream_feed_pcm (the same external-feed
pipeline screen-audio uses). Per-kind local_streams_ already allows mic +
screen + one aux to coexist; volume is a client-side gain multiply (the core's
vc_set_input_gain is mic-only/global). Aux is always-on (core never gates
AUX_DEVICE on VAD/PTT) and is tied to the voice session.
Windows: new Audio/InputDeviceCapture.cs (WASAPI shared-mode capture from a
real input endpoint + capture-endpoint enumeration); aux section in
AudioSettingsForm.cs; lifecycle in MainForm.cs; persistence in VoiceSettings.cs.
macOS: new Audio/InputDeviceCapture.swift (AVAudioEngine input-node tap pinned
to the chosen Core Audio device + device enumeration by stable UID); aux section
in SettingsWindowController.swift; lifecycle + UserDefaults persistence in
MainWindowController.swift; file registered in project.pbxproj.
Windows verified (C# solution builds clean; aux confirmed working). macOS build
+ E2E pending a Mac.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
"All apps except selected" previously captured the complement of a frozen
app snapshot in INCLUDE mode (missed late-launched apps and system sounds,
wasted captures on silent windows). It now opens a single ProcessLoopbackCapture
in EXCLUDE mode (AUDIOCLIENT_PROCESS_LOOPBACK_MODE_EXCLUDE_TARGET_PROCESS_TREE)
of the one chosen app — true system-mix-minus-one, dynamic so apps launched
after sharing starts are included. The picker enforces single-selection in
exclude mode (the activation params take one target PID).
Adds an "Exclude VoiceCat's own audio (prevents echo)" checkbox (default on,
entire-desktop only) that routes the desktop capture through the same EXCLUDE
path targeting our own process id, killing the whole-device self-echo loop.
No C++/ABI changes. Updates voice.md and PROGRESS.md.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Adds "only selected apps" and "all apps except selected" screen-audio
modes to the Windows client, alongside the existing entire-desktop path.
Per-app capture uses WASAPI process loopback (AUDCLNT_ACTIVATIONTYPE_
PROCESS_LOOPBACK) via ProcessLoopbackCapture, mixed by ProcessAudioMixer
and fed to the core through vc_stream_feed_pcm (external_feed=1 so the
core skips its own loopback device).
Init must pass AUDCLNT_STREAMFLAGS_LOOPBACK | EVENTCALLBACK |
AUTOCONVERTPCM; the LOOPBACK flag is what makes the virtual endpoint
deliver rendered audio (without it every buffer is flagged SILENT) and
AUTOCONVERTPCM resamples the app's native format to 48k s16.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
