之前写到了 屏幕共享的调起 、 进程间的通讯CFNotificationCenterGetDarwinNotifyCenter与进程间通信-App Groups
此篇文章基于屏幕共享的调起与进程间通信-App Groups、实现屏幕流的获取及推送（使用的aliRTC）
由于之前的socket传输一直不稳定、更换了传输方式。
aliRTC使用的是1.19版本以上、
已经开放了
通道、如果使用以下版本，请继续使用
通道（把屏幕流推入此通道即可）
可参考：官网文档
视频流处理
//
// AppGroupData.h
// Demo
//
// Created by 斌小狼 on 2021/4/1.
// Copyright © 2021 bxl. All rights reserved.
//
#import <AVFoundation/AVFoundation.h>
static NSString * _Nonnull kUserDefaultFrame = @"KEY_BXL_DEFAULT_FRAME"; // 接收屏幕共享(屏幕流)监听的Key
static NSString * _Nonnull kUserDefaultState = @"KEY_BXL_DEFAULT_STATE"; // 接收屏幕共享(开始/结束 状态)监听的Key
static NSString * _Nonnull kPropFormat = @"format";
static NSString * _Nonnull kPropWidth = @"width";
static NSString * _Nonnull kPropHeight = @"height";
static NSString * _Nonnull kPropStrideY = @"strideY";
static NSString * _Nonnull kPropStrideU = @"strideU";
static NSString * _Nonnull kPropStrideV = @"strideV";
static NSString * _Nonnull kPropDataLength = @"dataLength";
static NSString * _Nonnull kPropData = @"data";
static NSString * _Nonnull kPropRotation = @"rotation";
@interface AppGroupData : NSObject
+ (NSDictionary *_Nonnull)packetWithSampleBuffer:(CMSampleBufferRef _Nullable )sampleBuffer;
@end
//
// AppGroupData.m
// Demo
//
// Created by 斌小狼 on 2021/4/1.
// Copyright © 2021 bxl. All rights reserved.
//
#import "AppGroupData.h"
#import <CoreMedia/CoreMedia.h>
#import <ReplayKit/ReplayKit.h>
#import <Foundation/Foundation.h>
@interface AppGroupData ()
@end
@implementation AppGroupData
+ (NSDictionary *_Nonnull)packetWithSampleBuffer:(CMSampleBufferRef _Nullable )sampleBuffer{
// output data
int16_t format = -1;
int32_t strideY = -1;
int32_t strideU = -1;
int32_t strideV = -1;
uint8_t * dataPtr = NULL;
int32_t width = -1;
int32_t height = -1;
uint32_t dataLength = 0;
int32_t rotation = 0;
// get CVPixelBuffer
CVImageBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
const OSType pixel_format = CVPixelBufferGetPixelFormatType(pixelBuffer);
// CVPixelBuffer to yuv(nv12) data
if(pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarFullRange ||
pixel_format == kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange) {
CVPixelBufferLockBaseAddress(pixelBuffer, 0);
size_t w = CVPixelBufferGetWidth(pixelBuffer);
size_t h = CVPixelBufferGetHeight(pixelBuffer);
size_t src_y_stride = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);
size_t src_uv_stride = CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 1);
size_t bufferSize = w * h * 3 / 2;
// buffer
uint8_t * buffer = (uint8_t*)malloc(bufferSize);
unsigned char* dst = buffer;
unsigned char* src_y = (unsigned char*)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);
unsigned char* src_uv = (unsigned char *)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);
// copy y
size_t height_y = h;
for (unsigned int rIdx = 0; rIdx < height_y; ++rIdx, dst += w, src_y += src_y_stride) {
memcpy(dst, src_y, w);
}
// copy uv
size_t height_uv = h >> 1;
for (unsigned int rIdx = 0; rIdx < height_uv; ++rIdx, dst += w, src_uv += src_uv_stride) {
memcpy(dst, src_uv, w);
}
CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);
// frame
format = 3; // AliRtcVideoFormat_NV12;
strideY = (int32_t)w;
strideU = (int32_t)w;
strideV = (int32_t)w / 2;
dataPtr = buffer;
width = (int32_t)w;
height = (int32_t)h;
dataLength = bufferSize;
} else if(pixel_format == kCVPixelFormatType_32BGRA){ // CVPixelBuffer to rgb data
CVPixelBufferLockBaseAddress(pixelBuffer, 0);
size_t w = CVPixelBufferGetWidth(pixelBuffer);
size_t h = CVPixelBufferGetHeight(pixelBuffer);
uint8_t *buffer = (uint8_t *)CVPixelBufferGetBaseAddress(pixelBuffer);
size_t stride = CVPixelBufferGetBytesPerRow(pixelBuffer);
CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);
// frame
format = 0; // AliRtcVideoFormat_BGRA;
strideY = (int32_t)stride;
strideU = 0;
strideV = 0;
dataPtr = buffer;
width = (int32_t)w;
height = (int32_t)h;
dataLength = stride * h;
} else {
NSLog(@"(Error)unsupported pixelBuffer format");
return NULL;
}
if(format == -1 || dataPtr == NULL || width == -1 || height == -1 || dataLength == 0){
NSLog(@"(Error)wrong output params");
return NULL;
}
int32_t orientation = ((NSNumber *)CMGetAttachment(sampleBuffer,
(__bridge CFStringRef)RPVideoSampleOrientationKey,
NULL)).intValue;
switch (orientation) {
case kCGImagePropertyOrientationUp:
rotation = 0;
break;
case kCGImagePropertyOrientationLeft:
rotation = 90;
break;
case kCGImagePropertyOrientationDown:
rotation = 180;
break;
case kCGImagePropertyOrientationRight:
rotation = 270;
break;
default:
break;
}
//int64_t timeStampNs = CMTimeGetSeconds(CMSampleBufferGetPresentationTimeStamp(sampleBuffer)) * 1000000000;
NSData *data = [NSData dataWithBytesNoCopy:dataPtr length:dataLength];
// 组合成frame(一般屏幕采集都为nv12)
NSDictionary *nv12Frame = @{
kPropFormat: @(format),
kPropWidth: @(width),
kPropHeight: @(height),
kPropStrideY: @(strideY),
kPropStrideU: @(strideU),
kPropStrideV: @(strideV),
kPropDataLength: @(dataLength),
kPropData: data,
kPropRotation: @(rotation),
};
return nv12Frame;
}
@end
在Extension中获取数据流
//
// SampleHandler.m
// Demo
//
// Created by 斌小狼 on 2021/4/1.
// Copyright © 2021 bxl. All rights reserved.
//
#import "SampleHandler.h"
#import "AppGroupData.h"
static NSString * _Nonnull kAppGroup = @"你的app Group命名";
@interface SampleHandler()
@property (nonatomic, strong) NSUserDefaults *userDefaults;
@end
@implementation SampleHandler
- (void)broadcastStartedWithSetupInfo:(NSDictionary<NSString *,NSObject *> *)setupInfo {
// User has requested to start the broadcast. Setup info from the UI extension can be supplied but optional.
self.userDefaults = [[NSUserDefaults alloc] initWithSuiteName:kAppGroup];
[self.userDefaults setObject:@{@"state":@"初始化"} forKey:kUserDefaultState];//开始字段
}
- (void)broadcastPaused {
// User has requested to pause the broadcast. Samples will stop being delivered.
NSLog(@"暂停");
}
- (void)broadcastResumed {
// User has requested to resume the broadcast. Samples delivery will resume.
NSLog(@"继续");
}
- (void)broadcastFinished {
// User has requested to finish the broadcast.
[self.userDefaults setObject:@{@"state":@"停止"} forKey:kUserDefaultState];//结束字段
}
- (void)processSampleBuffer:(CMSampleBufferRef)sampleBuffer withType:(RPSampleBufferType)sampleBufferType {
//监听数据回流：
switch (sampleBufferType) {
case RPSampleBufferTypeVideo:
@autoreleasepool {
NSDictionary *nv12Frame = [AppGroupData packetWithSampleBuffer:sampleBuffer];
[self.userDefaults setObject:nv12Frame forKey:kUserDefaultFrame];//屏幕流数据
[self.userDefaults synchronize];
}
// Handle video sample buffer
break;
case RPSampleBufferTypeAudioApp:
// Handle audio sample buffer for app audio
// NSLog(@"--app audio---");
//音频流信息：44100，双声道，16bit
break;
case RPSampleBufferTypeAudioMic:
// Handle audio sample buffer for mic audio
// NSLog(@"-------输出--mic audio---");
//音频流信息：48000，单声道，16bit
// [self sendAudioData:sampleBuffer];
break;
default:
break;
}
}
@end
hostApp中屏幕流获取及使用
//
// RTCSampleChatViewController.m
// RtcSample
//
// Created by 斌小狼 on 2021/4/1.
// Copyright © 2021年 bxl. All rights reserved.
//
#import "RTCSampleChatViewController.h"
#import <AVFoundation/AVFoundation.h>
#import "AppGroupData.h"
#import <ReplayKit/ReplayKit.h>
static NSString * _Nonnull kAppGroup = @"你的app Group命名";
static void *KVOContext = &KVOContext;
@interface RTCSampleChatViewController
//....
//....
//....
@property (nonatomic, strong) NSUserDefaults *userDefaults;
@end
@implementation RTCSampleChatViewController
- (void)viewDidLoad {
[super viewDidLoad];
//....
//....
//通过UserDefaults建立数据通道
[self setupUserDefaults];
}
- (void)setupUserDefaults{
// 通过UserDefaults建立数据通道，接收Extension传递来的视频帧
self.userDefaults = [[NSUserDefaults alloc] initWithSuiteName:kAppGroup];
[self.userDefaults setObject:@{@"state":@"x"} forKey:kUserDefaultState];//给状态一个默认值
[self.userDefaults addObserver:self forKeyPath:kUserDefaultState options:NSKeyValueObservingOptionNew context:KVOContext];
[self.userDefaults addObserver:self forKeyPath:kUserDefaultFrame options:NSKeyValueObservingOptionNew context:KVOContext];
}
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSKeyValueChangeKey,id> *)change context:(void *)context{
if ([keyPath isEqualToString:kUserDefaultState]) {
NSDictionary *string = change[NSKeyValueChangeNewKey];
if ([string[@"state"] isEqual:@"初始化"]) {
//开启 RTC：外部视频输入通道，开始推送屏幕流（configLocalScreenPublish）
[self screenShareStart];
}
if ([string[@"state"] isEqual:@"停止"]) {
//关闭 RTC：外部视频输入通道，停止推送屏幕流
[self screenShareStop];
}
return;
}
if (![keyPath isEqualToString:kUserDefaultFrame] || startScreen == 0 ) {
return;
}
NSDictionary *NV12Frame = change[NSKeyValueChangeNewKey];
// 组建NV12 VideoFrame
AliRtcVideoDataSample *dataSample = [[AliRtcVideoDataSample alloc] init];
dataSample.dataPtr = (long)[NV12Frame[kPropData] bytes];
dataSample.format = (AliRtcVideoFormat)[NV12Frame[kPropFormat] intValue];
dataSample.width = [NV12Frame[kPropWidth] unsignedIntValue];
dataSample.height = [NV12Frame[kPropHeight] unsignedIntValue];
dataSample.strideY = [NV12Frame[kPropStrideY] unsignedIntValue];
dataSample.strideU = [NV12Frame[kPropStrideU] unsignedIntValue];
dataSample.strideV = [NV12Frame[kPropStrideV] unsignedIntValue];
dataSample.dataLength = [NV12Frame[kPropDataLength] unsignedIntValue];
dataSample.rotation = [NV12Frame[kPropRotation] unsignedIntValue];
// 输入yuv frame
//RTC：输入视频数据接口-----推送屏幕流到AliRtcVideosourceScreenShareType通道（如使用RTC1.19一下版本，请推送到AliRtcVideosourceCameraLargeType通道）
[self.engine pushExternalVideoFrame:dataSample sourceType:AliRtcVideosourceScreenShareType];
}
@end
关于屏幕共享篇：
感谢各位客官的帮助与支持🙏
更希望您能提出有意义的问题和建议、沟通会使我们共同成长～
