FFMPEG录屏（20）--- 枚举macOS下的窗口和屏幕列表，并获取名称缩略图等信息

在 macOS 下获取可屏幕共享的窗口和屏幕

在 macOS 下，我们可以通过使用 Core Graphics 和 Cocoa 框架来获取当前系统中可屏幕共享的窗口和屏幕信息。本文将详细介绍如何获取窗口和屏幕的 ID、标题、坐标、进程图标和缩略图等信息。

前提条件

在开始之前，请确保您的开发环境满足以下条件：

1. macOS 系统
2. 安装了 Xcode 或其他支持 Objective-C++ 开发的编译器

步骤

1. 包含必要的头文件

首先，包含必要的头文件：

#include "base/devices/screen/enumerator.h"
#include "base/devices/screen/darwin/desktop_configuration.h"
#include "base/devices/screen/desktop_geometry.h"
#include "base/devices/screen/utils.h"
#include "base/folder/folder.h"
#include "base/log/logger.h"#include <vector>
#include <functional>
#include <stdlib.h>
#include <string.h>#import <Cocoa/Cocoa.h>
#import <Foundation/Foundation.h>

2. 获取窗口信息

我们可以使用 CGWindowListCopyWindowInfo 函数获取当前系统中的窗口信息。以下是获取窗口信息的函数：

int enum_windows(const traa_size icon_size, const traa_size thumbnail_size,const unsigned int external_flags, std::vector<traa_screen_source_info> &infos) {CFArrayRef window_array = CGWindowListCopyWindowInfo(kCGWindowListOptionAll | kCGWindowListExcludeDesktopElements, kCGNullWindowID);if (!window_array)return false;MacDesktopConfiguration desktop_config =MacDesktopConfiguration::GetCurrent(MacDesktopConfiguration::TopLeftOrigin);CFIndex count = CFArrayGetCount(window_array);for (CFIndex i = 0; i < count; i++) {CFDictionaryRef window =reinterpret_cast<CFDictionaryRef>(CFArrayGetValueAtIndex(window_array, i));if (!window) {continue;}CFNumberRef window_id =reinterpret_cast<CFNumberRef>(CFDictionaryGetValue(window, kCGWindowNumber));if (!window_id) {continue;}traa_screen_source_info window_info;window_info.is_window = true;if (!CFNumberGetValue(window_id, kCFNumberSInt64Type, &window_info.id) || window_info.id <= 0) {continue;}CFNumberRef window_layer =reinterpret_cast<CFNumberRef>(CFDictionaryGetValue(window, kCGWindowLayer));if (!window_layer) {continue;}int layer;if (!CFNumberGetValue(window_layer, kCFNumberIntType, &layer)|| layer < kCGNormalWindowLevel || layer == kCGDockWindowLevel) {continue;}window_info.is_minimized = !is_window_on_screen(window);window_info.is_maximized = is_window_full_screen(desktop_config, window);if ((external_flags & TRAA_SCREEN_SOURCE_FLAG_IGNORE_MINIMIZED) && window_info.is_minimized) {continue;}CFNumberRef window_alpha =reinterpret_cast<CFNumberRef>(CFDictionaryGetValue(window, kCGWindowAlpha));if (!window_alpha) {continue;} else {int alpha;if (!CFNumberGetValue(window_alpha, kCFNumberIntType, &alpha) || alpha <= 0) {continue;}}CFNumberRef window_sharing_state =reinterpret_cast<CFNumberRef>(CFDictionaryGetValue(window, kCGWindowSharingState));if (!window_sharing_state) {continue;} else {int sharing_state;if (!CFNumberGetValue(window_sharing_state, kCFNumberIntType, &sharing_state) ||sharing_state != 1) {continue;}}CFNumberRef window_pid =reinterpret_cast<CFNumberRef>(CFDictionaryGetValue(window, kCGWindowOwnerPID));if (!window_pid) {continue;}std::string str_title = get_window_title(window);std::string str_owner_name = get_window_owner_name(window);if (str_title.empty() && str_owner_name.empty() &&!(external_flags & TRAA_SCREEN_SOURCE_FLAG_NOT_IGNORE_UNTITLED)) {continue;}if (str_title.empty()) {str_title = std::move(str_owner_name);}if (!str_title.empty()) {strncpy(const_cast<char *>(window_info.title), str_title.c_str(),std::min(sizeof(window_info.title) - 1, str_title.size()));}CGRect window_bounds = CGRectZero;if (CFDictionaryContainsKey(window, kCGWindowBounds)) {CFDictionaryRef rect = (CFDictionaryRef)CFDictionaryGetValue(window, kCGWindowBounds);if (rect) {CGRectMakeWithDictionaryRepresentation(rect, &window_bounds);}}if (window_bounds.size.width <= 96 || window_bounds.size.height <= 96) {continue;}window_info.rect = desktop_rect::make_xywh(window_bounds.origin.x, window_bounds.origin.y,window_bounds.size.width, window_bounds.size.height).to_traa_rect();NSRunningApplication *running_app = [NSRunningApplicationrunningApplicationWithProcessIdentifier:((__bridge NSNumber *)window_pid).intValue];if (running_app) {std::string process_path = [[running_app bundleURL] fileSystemRepresentation];if (!process_path.empty()) {strncpy(const_cast<char *>(window_info.process_path), process_path.c_str(),std::min(sizeof(window_info.process_path) - 1, process_path.size()));} else if (external_flags & TRAA_SCREEN_SOURCE_FLAG_IGNORE_NOPROCESS_PATH) {continue;}if (icon_size.width > 0 && icon_size.height > 0 && running_app.icon &&running_app.icon.representations.count > 0) {NSImage *icon = running_app.icon;NSBitmapImageRep *icon_rep =[[NSBitmapImageRep alloc] initWithData:[icon TIFFRepresentation]];if (icon_rep) {desktop_size icon_scaled_size =calc_scaled_size(desktop_size(icon_rep.size.width, icon_rep.size.height), icon_size);CGSize icon_scaled_ns_size =CGSizeMake(icon_scaled_size.width(), icon_scaled_size.height());NSBitmapImageRep *icon_scaled_image_rep = scale_image(icon_rep, icon_scaled_ns_size);if (icon_scaled_image_rep) {size_t icon_data_size = [icon_scaled_image_rep pixelsWide] *[icon_scaled_image_rep pixelsHigh] *[icon_scaled_image_rep samplesPerPixel] * sizeof(unsigned char);window_info.icon_data = new uint8_t[icon_data_size];window_info.icon_size = icon_scaled_size.to_traa_size();if (!window_info.icon_data) {LOG_ERROR("alloc memory for icon data failed");continue;}memcpy(const_cast<uint8_t *>(window_info.icon_data), [icon_scaled_image_rep bitmapData],icon_data_size);}}}}NSBitmapImageRep *origin_image_rep =get_image_rep(true, static_cast<CGWindowID>(window_info.id));if (!origin_image_rep) {continue;}if (thumbnail_size.width > 0 && thumbnail_size.height > 0) {NSImage *origin_image = [NSImage new];[origin_image addRepresentation:origin_image_rep];if (origin_image.size.width <= 1 || origin_image.size.height <= 1) {continue;}desktop_size scaled_size = calc_scaled_size(desktop_size(origin_image.size.width, origin_image.size.height), thumbnail_size);CGSize scaled_ns_size = CGSizeMake(scaled_size.width(), scaled_size.height());NSBitmapImageRep *scaled_image_rep = scale_image(origin_image_rep, scaled_ns_size);if (!scaled_image_rep) {continue;}size_t thumbnail_data_size = [scaled_image_rep pixelsWide] * [scaled_image_rep pixelsHigh] *[scaled_image_rep samplesPerPixel] * sizeof(unsigned char);window_info.thumbnail_data = new uint8_t[thumbnail_data_size];window_info.thumbnail_size = scaled_size.to_traa_size();if (!window_info.thumbnail_data) {LOG_ERROR("alloc memory for thumbnail data failed");continue;}memcpy(const_cast<uint8_t *>(window_info.thumbnail_data), [scaled_image_rep bitmapData],thumbnail_data_size);}infos.push_back(window_info);}CFRelease(window_array);return TRAA_ERROR_NONE;
}

3. 获取屏幕信息

我们可以使用 NSScreen 类获取当前系统中的屏幕信息。以下是获取屏幕信息的函数：

int enum_screens(const traa_size icon_size, const traa_size thumbnail_size,const unsigned int external_flags, std::vector<traa_screen_source_info> &infos) {NSArray *screen_array = NSScreen.screens;if (!screen_array) {return TRAA_ERROR_NONE;}for (size_t i = 0; i < screen_array.count; i++) {NSScreen *screen = screen_array[i];if (!screen) {continue;}CGDirectDisplayID screen_id = static_cast<CGDirectDisplayID>([[screen.deviceDescription objectForKey:@"NSScreenNumber"] unsignedIntValue]);CGRect screen_bounds = CGDisplayBounds(screen_id);NSBitmapImageRep *screen_image_rep = get_image_rep(false, screen_id);if (!screen_image_rep) {continue;}traa_screen_source_info screen_info;screen_info.is_window = false;screen_info.is_primary = CGDisplayIsMain(screen_id);screen_info.id = static_cast<int64_t>(screen_id);snprintf(const_cast<char *>(screen_info.title), sizeof(screen_info.title), "Display %d",static_cast<int>(i));screen_info.rect = desktop_rect::make_xywh(screen_bounds.origin.x, screen_bounds.origin.y,screen_bounds.size.width, screen_bounds.size.height).to_traa_rect();if (thumbnail_size.width > 0 && thumbnail_size.height > 0) {NSImage *screen_image = [NSImage new];[screen_image addRepresentation:screen_image_rep];desktop_size scaled_size = calc_scaled_size(desktop_size(screen_image.size.width, screen_image.size.height), thumbnail_size);CGSize scaled_ns_size = CGSizeMake(scaled_size.width(), scaled_size.height());NSBitmapImageRep *scaled_image_rep = scale_image(screen_image_rep, scaled_ns_size);if (!scaled_image_rep) {continue;}size_t thumbnail_data_size = [scaled_image_rep pixelsWide] * [scaled_image_rep pixelsHigh] *[scaled_image_rep samplesPerPixel] * sizeof(unsigned char);screen_info.thumbnail_data = new uint8_t[thumbnail_data_size];screen_info.thumbnail_size = scaled_size.to_traa_size();if (!screen_info.thumbnail_data) {LOG_ERROR("alloc memory for thumbnail data failed");continue;}memcpy(const_cast<uint8_t *>(screen_info.thumbnail_data), [scaled_image_rep bitmapData],thumbnail_data_size);}infos.push_back(screen_info);}return TRAA_ERROR_NONE;
}

4. 枚举屏幕和窗口信息

最后，我们可以通过调用 enum_windows 和 enum_screens 函数来枚举当前系统中的窗口和屏幕信息：

int screen_source_info_enumerator::enum_screen_source_info(const traa_size icon_size,const traa_size thumbnail_size,const unsigned int external_flags,traa_screen_source_info **infos,int *count) {if (__builtin_available(macOS 11, *)) {if (!CGPreflightScreenCaptureAccess()) {CGRequestScreenCaptureAccess();return TRAA_ERROR_PERMISSION_DENIED;}}std::vector<traa_screen_source_info> sources;if (!(external_flags & TRAA_SCREEN_SOURCE_FLAG_IGNORE_WINDOW)) {enum_windows(icon_size, thumbnail_size, external_flags, sources);}if (!(external_flags & TRAA_SCREEN_SOURCE_FLAG_IGNORE_SCREEN)) {enum_screens(icon_size, thumbnail_size, external_flags, sources);}if (sources.size() == 0) {return traa_error::TRAA_ERROR_NONE;}*count = static_cast<int>(sources.size());*infos = reinterpret_cast<traa_screen_source_info *>(new traa_screen_source_info[sources.size()]);if (*infos == nullptr) {LOG_ERROR("alloca memroy for infos failed");return traa_error::TRAA_ERROR_OUT_OF_MEMORY;}for (size_t i = 0; i < sources.size(); ++i) {auto &source_info = sources[i];auto &dest_info = (*infos)[i];memcpy(&dest_info, &source_info, sizeof(traa_screen_source_info));if (std::strlen(source_info.title) > 0) {strncpy(const_cast<char *>(dest_info.title), source_info.title,std::min(sizeof(dest_info.title) - 1, std::strlen(source_info.title)));}if (std::strlen(source_info.process_path) > 0) {strncpy(const_cast<char *>(dest_info.process_path), source_info.process_path,std::min(sizeof(dest_info.process_path) - 1, std::strlen(source_info.process_path)));}}return TRAA_ERROR_NONE;
}

总结

通过上述步骤，我们可以在 macOS 下获取当前系统中可屏幕共享的窗口和屏幕信息，包括窗口和屏幕的 ID、标题、坐标、进程图标和缩略图等信息。希望这篇文章对您有所帮助。

源码传送

traa