alphawindow 0.1.2

Windows-first window automation abstractions with pluggable input and output modes.

AlphaWindow

简体中文

AlphaWindow is a Windows-first automation abstraction layer. It exposes one session API for window operations while allowing callers to choose different input and output modes.

AlphaWindow is meant to model target-window automation, not global "computer use" control. The same high-level operations can be backed by no-op inspection, window messages, UI Automation, foreground input, guarded foreground input, or optional hook-assisted virtual input.

Scope

AlphaWindow separates four concerns:

• Window discovery and state: WindowResolver, WindowSelector, and WindowSnapshot.
• Output: state inspection, direct window capture, explicit monitor capture, desktop-region capture, hook telemetry, or no output.
• Input: dry-run, window messages, UIA, global foreground input, guarded foreground input, isolated hook input, or virtualized hook input.
• Safety contracts: profile compatibility, explicit fallback modes, hook requirements, prefetch TTL, and fake backends for deterministic tests.

The project currently focuses on the abstraction and compatibility layer. Native pynput, UIA, and hook implementations are intentionally kept behind protocols so callers can plug in their own adapters without changing automation code. The exceptions are an experimental PyWinRT-backed Windows Graphics Capture path and classic Win32/GDI window capture paths. WGC can capture a native Direct3D surface, read it back to CPU memory, or keep a persistent frame cache for low-latency repeated screenshots. Win32/GDI capture can use PrintWindow or BitBlt against a target HWND.

Supported Today

• Built-in I/O profiles for every declared input and output mode, including inspect, observe, desktop_observe, monitor_observe, dry_run, win32_message, message_only, uia_control, uia_visual, global_input, foreground_visual, guarded_input, guarded_desktop, isolated_observe, isolated_telemetry, virtual_window, virtual_telemetry, and virtual_input_only.
• A WindowSession API for prefetch, capture, observe, click, key_down, key_up, and type_text.
• Generic delegation backends for message, UIA, foreground, guarded foreground, state, desktop-region, hook-telemetry, and no-output modes.
• Compatibility checks so a backend cannot silently fall back to a broader side-effect mode.
• Hook-aware isolated and virtualized input backends that accept pluggable hook managers and virtual input transports.
• Pluggy-based plugin registry for installed packages to register additional capture and mouse/keyboard input methods without adding hardware SDKs to core.
• Deterministic prefetch behavior: snapshots are reused within prefetch_ttl_seconds, rejected when stale, and revalidated through a resolver is_valid hook when provided.
• DPI-aware snapshots and capture requests: WindowSnapshot.dpi is carried into operation normalization and DirectX capture requests.
• Relative point normalization: session.click(0.5, 0.5) resolves against the current target window rectangle.
• HDR-aware DirectX/Windows Graphics Capture model: DirectXCaptureOutputBackend builds capture requests for an injected DirectXCapturePipeline, selects FP16/scRGB for HDR targets, selects BGRA8/sRGB for SDR, and preserves frame DPI and SDR white-level metadata.
• CPU frame conversion: CpuFrame supports FP16/scRGB to SDR BGRA8 tone mapping, pure-Python PNG export, and optional Pillow / numpy output formats selected by CaptureOutputFormat.
• Experimental native WGC pipeline: WinrtWgcCapturePipeline uses PyWinRT, creates a Direct3D11 device, creates a window or monitor GraphicsCaptureItem, starts a free-threaded WGC frame pool, returns a CaptureFrame containing the native IDirect3DSurface, and can read it back with capture_cpu().
• Explicit monitor capture requests: MonitorSnapshot, CaptureTargetKind.MONITOR, and DirectXCaptureConfig.create_monitor_request() model WGC display capture through create_for_monitor, including HDR/scRGB and DPI metadata for the selected monitor.
• Persistent native WGC frame cache: WinrtWgcFrameCache keeps the WGC session and D3D11 device alive, tracks the newest frame, can wait for a bounded fresh frame, and can run a before_readback hook while holding that frame so external labels can be sampled against the same image moment.
• Classic native Win32 window capture: Win32WindowCaptureBackend supports explicit win32_print_window and win32_bitblt_window methods, returning CpuFrame without falling back to global screenshots.
• A Windows-only alphawindow desktop test tool that starts from the current working directory, lets a user click-to-attach a target window handle, previews WGC captures, switches between cached, single-shot, and attached-window monitor capture, selects 1 Hz, 30 Hz, or 120 Hz refresh, and reports the last capture time plus the average of the latest 30 captures.
• PyPI packaging for pip install alphawindow and typed package data via py.typed.
• Tests that cover profile coverage, compatibility failures, prefetch reuse/refresh behavior, hook backend contracts, DirectX/HDR capture contracts, native WGC dependency behavior, generic backends, CLI preview controller behavior, packaging import behavior, and the publish workflow.

Screenshot Support Matrix

AlphaWindow treats screenshot mode as an explicit choice. It does not silently fall back from one capture path to another.

Window Targets

Mode	Target	Entry points	Current status	Best fit	Limits
WGC cached window capture	HWND / WindowSnapshot	wgc_window_cached, WinrtWgcFrameCache.start_for(window, request)	Supported as experimental native PyWinRT capture	Repeated screenshots of a normal window, borderless window, or compositor-visible app	Depends on Windows Graphics Capture allowing that window; fails closed on WGC/readback/tone-map errors.
WGC single-shot window capture	HWND / WindowSnapshot	wgc_window_single, WinrtWgcCapturePipeline.capture_cpu(window, request)	Supported as experimental native PyWinRT capture	One-off validation screenshots or simple tooling	Recreates the WGC session per capture, so it is not the preferred high-frequency path.
DirectX capture model	WindowSnapshot	DirectXCaptureConfig.create_request(), DirectXCaptureOutputBackend with an injected pipeline	Supported as an abstraction and contract	External adapters that want AlphaWindow's HDR/DPI/request normalization	The injected pipeline must provide the real capture implementation.
Desktop-region output mode	Window rectangle in desktop coordinates	desktop_observe, OutputMode.DESKTOP_REGION	Mode and compatibility contract are supported	Foreground/compositor-visible targets when an external adapter supplies desktop-region capture	Core package does not yet ship a native desktop-region screenshot adapter.
Win32 PrintWindow capture	HWND / WindowSnapshot	win32_print_window, Win32WindowCaptureBackend(method="win32_print_window")	Supported through pywin32/GDI	Legacy Win32 apps, dialogs, or apps where WGC is not desired	Uses PrintWindow(hwnd, hdc, 2); many GPU/game surfaces may return black, stale, or incomplete pixels.
Win32 BitBlt window capture	HWND / WindowSnapshot	win32_bitblt_window, Win32WindowCaptureBackend(method="win32_bitblt_window")	Supported through pywin32/GDI	Visible windows and direct window DC copying	Uses GetWindowDC + BitBlt(..., SRCCOPY); occlusion/compositor/GPU behavior can limit results.

Fullscreen And Exclusive Targets

Scenario	Recommended mode	Current status	What it can capture	What it cannot guarantee
Borderless fullscreen / fullscreen windowed game visible in the compositor	wgc_monitor_cached / WinrtWgcFrameCache.start_for(monitor, request)	Supported as experimental native monitor WGC capture	The whole monitor containing the attached window, including compositor-visible fullscreen output	It captures unrelated pixels on that monitor and is not target-window isolated.
Fullscreen app where window-target WGC is the wrong abstraction	wgc_monitor_cached	Supported as explicit monitor capture, not fallback	Display output if Windows Graphics Capture exposes the monitor frame	Protected, blocked, or non-composited content can still fail or return unusable frames.
True exclusive fullscreen swap chain	None	Not supported as a guaranteed mode	No guaranteed capture path in AlphaWindow today	AlphaWindow does not bypass exclusive fullscreen restrictions, driver behavior, anti-cheat policy, or protected content.
Secure desktop, protected video, anti-cheat blocked content, or protected process	None	Not supported	Nothing guaranteed	No kernel driver, privilege escalation, protected-process bypass, or anti-cheat bypass is provided.

Input Support Matrix

AlphaWindow uses the same high-level operations for mouse and keyboard input: click, key_down, key_up, and type_text. The selected input backend decides whether those operations become window messages, UI Automation actions, global foreground input, or hook-assisted virtual input.

Mouse And Keyboard Modes

Mode	Entry points / profiles	Mouse behavior	Keyboard behavior	Main device impact	Current status and limits
Dry run	dry_run, inspect, observe, desktop_observe, monitor_observe	Records the requested mouse operation without executing it.	Records the requested keyboard operation without executing it.	None.	Built in through DryRunInputBackend; useful for tests and planning.
Window message input	win32_message, message_only, InputMode.MESSAGE	External backend can translate clicks/moves to PostMessage/SendMessage style mouse messages for a target HWND.	External backend can translate key events/text to window messages.	Does not need to move the primary cursor when the target accepts messages.	Protocol and compatibility slot are built in; native PostMessage/SendMessage adapter is not shipped yet, and many games/custom renderers ignore these messages.
UI Automation input	uia_control, uia_visual, InputMode.UIA	External UIA adapter can invoke standard controls or patterns instead of physical mouse movement.	External UIA adapter can set text or invoke standard control patterns.	Usually avoids primary mouse/keyboard takeover.	Protocol slot is built in; native UIA adapter is not shipped yet and this is not a general game input path.
Foreground global input	global_input, foreground_visual, InputMode.FOREGROUND	External backend can use pynput, SendInput, or another global input library against the foreground target.	External backend can emit global key events/text through pynput, SendInput, or equivalent.	Affects the active desktop and primary mouse/keyboard stream.	Compatibility slot is built in; native foreground input adapter is planned, not shipped. Requires focus/foreground correctness.
Guarded foreground input	guarded_input, guarded_desktop, InputMode.GUARDED_FOREGROUND	Same class of global mouse input as foreground mode, with an adapter responsible for focus/cursor save and restore.	Same class of global keyboard input as foreground mode, with cleanup around focus/key state.	Still affects the primary input stream while the operation is running.	Compatibility slot is built in; guard implementation is adapter-provided. It reduces cleanup risk but is not input isolation.
Isolated hook input	isolated_observe, isolated_telemetry, InputMode.ISOLATED, IsolatedInputBackend	Hook manager can windowize or suppress real mouse input for the target before optionally delegating to another backend.	Hook manager can windowize or suppress target-local keyboard input before optional delegation.	Intended to reduce or prevent target impact from the user's primary devices, depending on hook implementation.	Hook-aware backend contract is built in; production hook manager/DLL injection is not shipped. Fails closed without hook capability.
Virtualized hook input	virtual_window, virtual_telemetry, virtual_input_only, InputMode.VIRTUALIZED, VirtualizedInputBackend	Sends target-local virtual mouse operations through a VirtualInputTransport after hook injection.	Sends target-local virtual keyboard operations through a VirtualInputTransport after hook injection.	Designed for multi-window automation without taking over the primary mouse/keyboard, if the hook and transport support it.	Backend contract is built in; requires both hook manager and transport. Ready-made IPC transport is not shipped yet.
Custom delegated input	DelegatingInputBackend with message, uia, foreground, or guarded_foreground mode	Caller supplies the concrete mouse implementation.	Caller supplies the concrete keyboard implementation.	Depends on the chosen custom backend.	Supported extension point for pywin32, pynput, SendInput, UIA, app-specific IPC, or test doubles. Hook modes must use the dedicated hook-aware backends.

Hook Modes

Hook path	Required pieces	What it is for	What it is not
Isolation hook	HookManager plus optional delegated input backend	Blocking, rewriting, or observing target-local mouse/keyboard input so real user input can be isolated from the target.	It is not a complete implementation by itself; the package only defines the contract.
Virtual input hook	HookManager plus VirtualInputTransport	Sending per-window or per-process virtual mouse/keyboard operations without relying on the primary cursor or global keyboard stream.	It is not a kernel driver, anti-cheat bypass, or universal game-input solution.
Hook telemetry	Hook-capable input profile plus OutputMode.HOOK_TELEMETRY	Reading hook-side labels, events, or state that can be paired with capture frames.	It is not OCR/image matching and does not replace screenshot capture.

Input Language Utilities

The package also exposes small Windows utilities for keyboard layout and CapsLock state:

Utility	Purpose	Notes
switch_input_language(language="next", hwnd=None)	Requests a target or foreground window to switch input language through WM_INPUTLANGCHANGEREQUEST.	language accepts next, previous, common aliases such as en-US / zh-CN, or a Windows KLID such as 00000409.
set_caps_lock(enabled)	Sets global CapsLock state if it differs from the requested value.	CapsLock is a desktop keyboard toggle, not a target-window-local state.
switch_input_state(language=None, caps_lock=None, toggle_caps_lock=False, hwnd=None)	Convenience wrapper that can switch language and set/toggle CapsLock in one call.	Exposes user32 injection for tests or custom wrappers.

Plugin API

AlphaWindow uses pluggy for optional extension packages. This is the right place for hardware device bridges, proprietary SDK adapters, app-specific capture engines, or experimental input transports that should not become core dependencies. See the formal plugin protocol in docs/plugin-protocol.zh-CN.md.

alphawindow-xxx is only a recommended package naming convention. AlphaWindow does not auto-import packages by name prefix. Automatic discovery only loads the alphawindow.plugins entry point group.

A plugin package exposes methods through the alphawindow.plugins entry point group:

[project.entry-points."alphawindow.plugins"]
my_hardware = "my_hardware_plugin"

The plugin module returns method descriptors from hook implementations:

from alphawindow import Capability, InputMode, OutputMode
from alphawindow.plugins import PluginCaptureMethod, PluginInputMethod, hookimpl

class HardwareCaptureBackend:
    mode = OutputMode.WINDOW_CAPTURE
    capabilities = frozenset({Capability.WINDOW_CAPTURE})

    def __init__(self, *, device_id: str):
        self.device_id = device_id

    def capture(self, target):
        ...

    def observe(self, target):
        return target

class HardwareInputBackend:
    mode = InputMode.FOREGROUND
    capabilities = frozenset({Capability.GLOBAL_INPUT})

    def __init__(self, *, device_id: str):
        self.device_id = device_id

    def perform(self, target, operation):
        ...

@hookimpl
def alphawindow_capture_methods():
    return [
        PluginCaptureMethod(
            name="hardware_capture",
            factory=HardwareCaptureBackend,
            mode=OutputMode.WINDOW_CAPTURE,
            capabilities=frozenset({Capability.WINDOW_CAPTURE}),
        )
    ]

@hookimpl
def alphawindow_input_methods():
    return [
        PluginInputMethod(
            name="hardware_input",
            factory=HardwareInputBackend,
            mode=InputMode.FOREGROUND,
            capabilities=frozenset({Capability.GLOBAL_INPUT}),
        )
    ]

Callers discover installed plugins and instantiate backends by method name:

from alphawindow import discover_plugins

registry = discover_plugins()
output_backend = registry.create_capture_backend("hardware_capture", device_id="cap0")
input_backend = registry.create_input_backend("hardware_input", device_id="kbd0")

Plugin method names must be unique. Backends returned by a plugin are checked against the advertised mode and capabilities before use, so an invalid plugin fails closed instead of being silently accepted.

Built-in Profiles

Profile	Input mode	Output mode	Current behavior
inspect	dry_run	state	Inspect resolver state only.
observe	dry_run	window_capture	Observe/capture without input.
desktop_observe	dry_run	desktop_region	Observe through desktop-region output.
monitor_observe	dry_run	monitor_capture	Observe through explicit monitor capture.
dry_run	dry_run	none	Record planned operations without side effects.
win32_message	message	window_capture	Adapter slot for window-message input plus window capture.
message_only	message	none	Adapter slot for message input without output.
uia_control	uia	state	Adapter slot for UIA control operations.
uia_visual	uia	window_capture	Adapter slot for UIA input plus visual capture.
global_input	foreground	desktop_region	Adapter slot for pynput/SendInput-style foreground input.
foreground_visual	foreground	window_capture	Foreground input with target-window output.
guarded_input	guarded_foreground	window_capture	Adapter slot for foreground input with focus/cleanup guards.
guarded_desktop	guarded_foreground	desktop_region	Guarded foreground input with desktop-region capture.
isolated_observe	isolated	window_capture	Requires a hook-capable input backend; can isolate real mouse input before optional delegated input.
isolated_telemetry	isolated	hook_telemetry	Requires hook support for isolation and telemetry.
virtual_window	virtualized	window_capture	Requires hook support and a virtual input transport.
virtual_telemetry	virtualized	hook_telemetry	Requires hook support for virtual input and telemetry.
virtual_input_only	virtualized	none	Requires hook support; routes virtual input without output capture.

Considered Design Surface

These capabilities are represented in the model and can be supplied by external adapters today:

• Native window resolution by hwnd, title, class name, PID, visibility, DPI, and process/thread metadata.
• Direct window output through built-in PrintWindow and BitBlt, plus extension slots for DWM thumbnails or application-specific capture.
• HDR-aware DirectX/Windows Graphics Capture output with explicit pixel format, color space, buffer count, free-threaded frame-pool preference, DPI, target kind, and SDR white-level metadata.
• Native WGC capture through PyWinRT for callers that want a window or monitor IDirect3DSurface, a tone-mapped CPU image, or a persistent latest-frame cache for high-frequency capture loops.
• Monitor-targeted WGC output for cases where the desired image is the visible display containing a target window, including borderless-fullscreen style scenarios where window-target capture is the wrong abstraction.
• Desktop-region output for modes where the target must be foreground or compositor-visible.
• Window-message input for controls that accept PostMessage/SendMessage style input.
• Windows UI Automation input for standard controls.
• Foreground input through pynput, SendInput, or equivalent global input libraries.
• Guarded foreground input that restores focus/cursor state after an operation.
• Optional hook-assisted mouse and keyboard windowization, including target-local telemetry.
• Per-window or per-process virtual input transports for multi-window automation without taking over the primary mouse.

Not Supported Yet

The package still keeps most native adapters out of core. In particular, it does not currently include:

• A built-in pywin32 WindowResolver.
• A general-purpose native resolver API in the core session layer; the current Win32 HWND picker exists only for the alphawindow test tool.
• Color-managed HDR preview or HDR-preserving image/video encoders.
• Advanced tone-mapping controls beyond the built-in ACES-style SDR conversion.
• Built-in PostMessage, UIA, pynput, or SendInput input backends.
• A production DLL injection or hook manager.
• A ready-made virtual input IPC transport.
• OCR, image matching, accessibility tree querying, or high-level wait/retry helpers.
• Non-Windows native backends.
• Guaranteed capture of true exclusive fullscreen swap chains, protected content, anti-cheat blocked content, secure desktops, or other content Windows/WGC refuses to expose.
• Kernel drivers, privilege escalation, protected-process bypasses, anti-cheat bypasses, or game-specific automation logic.

The desktop test tool is intended for manual adapter verification. Its attach action observes the next left-click through pynput, so that click may still focus or interact with the target application. The preview is SDR/tone-mapped for Tk display and is not a color-managed HDR viewer.

Window screenshot failures are fail-closed. If WGC frame creation, Win32/GDI capture, readback, or tone mapping fails, AlphaWindow surfaces that exception to the caller/UI instead of falling back to desktop screenshots, PIL ImageGrab, or another global capture path.

The wgc_monitor_cached mode is an explicit whole-monitor capture mode, not an automatic fallback. It can help test borderless-fullscreen or compositor-visible game output because it captures the monitor that contains the attached window. It can also expose unrelated pixels on that display, and it still cannot bypass exclusive fullscreen, protected content, or anti-cheat restrictions.

Hook-capable profiles fail closed unless the provided backend advertises hook capability. VirtualizedInputBackend also requires a VirtualInputTransport.

Planned Features

• pywin32-based resolver and state backend for common window selectors.
• Native capture adapter for desktop-region capture.
• Broader Windows Graphics Capture resize handling.
• HDR-preserving image encoders and richer color-management metadata.
• pynput/SendInput foreground input backend and guarded foreground focus restoration.
• Window-message and UIA adapters for common controls.
• A documented hook manager interface with a sample user-mode hook implementation.
• A sample virtual input transport suitable for target-window mouse/keyboard windowization.
• More examples showing how to share one automation script across dry-run, message, foreground, isolated, and virtualized modes.
• Expanded integration tests for real Windows adapters while keeping unit tests deterministic through fake backends.

Install

From PyPI:

pip install alphawindow

From this checkout:

pip install .

Native Windows adapters are optional:

pip install "alphawindow[native]"

Pillow and numpy screenshot conversions are optional:

pip install "alphawindow[image]"

Command-line Test Tool

alphawindow

The command opens a small Windows desktop tool using the current working directory as its workspace label. Click Attach Window, click a target window, then choose:

• wgc_window_cached for a persistent window-target WGC readback loop.
• wgc_window_single for one WGC window session per capture.
• wgc_monitor_cached for a persistent WGC readback loop against the monitor containing the attached window.
• win32_print_window for classic PrintWindow(hwnd, hdc, 2) capture.
• win32_bitblt_window for classic GetWindowDC + BitBlt(..., SRCCOPY) capture.
• HDR mode: auto, force, or off.
• Refresh rate: 1, 30, or 120 Hz.

The preview refreshes in the app and shows the latest capture time plus the average of the most recent 30 captures. Use alphawindow --workspace D:\path\to\workspace to show a different workspace path in the tool.

Import

import alphawindow

from alphawindow import (
    AutomationConfig,
    CaptureOutputFormat,
    CaptureTargetKind,
    DirectXCaptureConfig,
    MonitorSnapshot,
    WgcFrameReadbackResult,
    Win32WindowCaptureBackend,
    Win32WindowCaptureMethod,
    WinrtWgcCapturePipeline,
    WinrtWgcFrameCache,
    InputMode,
    OutputMode,
    WindowSelector,
    WindowSession,
    get_profile,
    switch_input_state,
)

print(alphawindow.__version__)
print(get_profile("observe").input_mode is InputMode.DRY_RUN)
print(CaptureOutputFormat.NUMPY_BGR.value)
print(DirectXCaptureConfig().hdr_mode.value)
print(CaptureTargetKind.MONITOR.value)
print(MonitorSnapshot.__name__)
print(WgcFrameReadbackResult.__name__)
print(Win32WindowCaptureBackend.__name__)
print(Win32WindowCaptureMethod.PRINT_WINDOW.value)
print(WinrtWgcCapturePipeline.__name__)
print(WinrtWgcFrameCache.__name__)
print(switch_input_state.__name__)

Native WGC Screenshot

from alphawindow import DirectXCaptureConfig, HdrCaptureMode, WindowSnapshot
from alphawindow.native_wgc import WinrtWgcCapturePipeline

target = WindowSnapshot(
    hwnd=123456,
    title="Target",
    rect=(0, 0, 1920, 1080),
    dpi=144,
    metadata={"hdr_enabled": True, "sdr_white_level_nits": 203.0},
)
request = DirectXCaptureConfig(hdr_mode=HdrCaptureMode.AUTO).create_request(target)

pipeline = WinrtWgcCapturePipeline(timeout_seconds=2.0)
frame = pipeline.capture_cpu(target, request, tone_map=True)
frame.save_png("target.png")
pipeline.close()

capture_cpu() and the Win32 capture backends return CpuFrame by default. Callers can choose a higher-level image output format explicitly:

from alphawindow import CaptureOutputFormat

pil_image = frame.to_output(CaptureOutputFormat.PILLOW)      # PIL.Image.Image, RGB
opencv_bgr = frame.to_output(CaptureOutputFormat.NUMPY_BGR)  # numpy uint8, H x W x 3, BGR
numpy_rgb = frame.to_output(CaptureOutputFormat.NUMPY_RGB)   # numpy uint8, H x W x 3, RGB
numpy_bgra = frame.to_output("numpy_bgra")                   # numpy uint8, H x W x 4, BGRA

Numpy output is zero-copy by default when the frame is already SDR BGRA8. numpy_bgra, numpy_bgr, and numpy_rgb are views over CpuFrame.data; numpy_bgr drops alpha through strides, and numpy_rgb reverses channels through a negative stride. If a downstream library requires a C-contiguous array, request a copy explicitly:

opencv_bgr = frame.to_output(CaptureOutputFormat.NUMPY_BGR, copy=True)

The preview controller exposes the same choice through CaptureSettings while still preserving the underlying CpuFrame:

from alphawindow import CaptureOutputFormat
from alphawindow.cli_app import CaptureSettings

settings = CaptureSettings(
    output_format=CaptureOutputFormat.NUMPY_BGR,
    output_copy=False,
)
result = controller.capture(target, settings)
frame = result.frame      # CpuFrame
image = result.output     # zero-copy numpy view in the requested format

To capture the full monitor containing a target, pass a MonitorSnapshot and create a monitor request:

from alphawindow import DirectXCaptureConfig, HdrCaptureMode, MonitorSnapshot
from alphawindow.native_wgc import WinrtWgcCapturePipeline

target = MonitorSnapshot(
    hmonitor=123456,
    device_name="DISPLAY1",
    rect=(0, 0, 3840, 2160),
    work_rect=(0, 0, 3840, 2080),
    dpi=144,
    primary=True,
    metadata={"hdr_enabled": True, "sdr_white_level_nits": 203.0},
)
request = DirectXCaptureConfig(hdr_mode=HdrCaptureMode.AUTO).create_monitor_request(target)

pipeline = WinrtWgcCapturePipeline(timeout_seconds=2.0)
frame = pipeline.capture_cpu(target, request, tone_map=True)
frame.save_png("monitor.png")
pipeline.close()

For repeated capture, keep the WGC session alive and read back the latest frame:

from alphawindow.native_wgc import WinrtWgcFrameCache

def sample_labels(frame_info):
    return {"sequence": frame_info["sequence"], "labels": []}

cache = WinrtWgcFrameCache.start_for(target, request, timeout_seconds=2.0)
try:
    result = cache.readback_latest_cpu(
        tone_map=True,
        fresh_max_age_ms=8.0,
        fresh_wait_ms=16.0,
        before_readback=sample_labels,
    )
    result.cpu.save_png("target.png")
    print(result.info["size"], result.info["content_size"], result.hook_result)
finally:
    cache.close()