版本记录

版本号	时间
V1.0	2017.08.17

前言

针对短视频的上传、编辑等功能有很多的SDK，比如腾讯的SDK、七牛的SDK等，这里我就说一下我用过的美摄的SDK - 1.8.0，希望对大家有所帮助。感兴趣的可以看我上面几篇。
1. 美摄SDK的使用（一）—— 产品介绍
2. 美摄SDK的使用（二）—— 框架介绍

短视频录制工具类的封装

下面就是短视频录制中工具类的封装的实现。

1. JJNvsLiveContext.h

#import <Foundation/Foundation.h>
#import "NvsStreamingContext.h"

@interface JJNvsLiveContext : NSObject

@property (nonatomic, strong) NvsStreamingContext *context;//流媒体上下文

//开始录制
- (BOOL)startRecording:(NSString *)path;

//结束录制
- (BOOL)stopRecording;

//添加预览界面
- (BOOL)addPreView:(NvsLiveWindow *)preView;

//开始预览
- (BOOL)startCapturePreview;

//保存流媒体
- (void)saveRecording:(NSString *)path;

//销毁流媒体上下文
- (void)destroyInstance;

//开启美颜
- (void)appendBeautyCaptureVideoFx;

//获取视频流时间
- (NSInteger)getVideoStreamDuration;

//是否是前置摄像头
- (BOOL)isFrontCamera;

//切换摄像图头
- (void)switchCamera;

//开关闪光灯
- (void)startFlight;

- (void)stop;

@end

2. JJNvsLiveContext.m

#import "JJNvsLiveContext.h"

@interface JJNvsLiveContext () <NvsStreamingContextDelegate>

@property (nonatomic, strong) NvsTimeline *timeLine;//时间线
@property (nonatomic, weak) NvsLiveWindow *preView;
@property (nonatomic, assign) BOOL isOpen;
@property (nonatomic, assign) BOOL isFront;

@end

@implementation JJNvsLiveContext

static NSString *tempPath;

#pragma mark - Override Base Function

- (void)dealloc
{
    DDLogWarn(@"%@ 已释放", self);
}

#pragma mark - Object Private Function

- (BOOL)startCapturePreview:(unsigned int)currentDeviceIndex
{
    return [self.context startCapturePreview:currentDeviceIndex videoResGrade:NvsVideoCaptureResolutionGradeHigh flags:0 aspectRatio:nil];
}

- (void)video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    if (error != NULL)
    {
        DDLogError(@"Save image failed");
    }
    else
    {
        DDLogInfo(@"Save image successful");
    }
}

#pragma mark - Object Public Function

//开始录制

- (BOOL)startRecording:(NSString *)path
{
    tempPath = path;
    BOOL isSuccess = [self.context startRecording:path withFlags:2];
    return isSuccess;
}

//结束录制

- (void)stopRecording
{
    [self.context stopRecording];
}

//添加预览界面

- (BOOL)addPreView:(NvsLiveWindow *)preView
{
    self.preView = preView;
    return [self.context connectCapturePreviewWithLiveWindow:preView];
}

//开始预览

- (BOOL)startCapturePreview
{
    return [self startCapturePreview:0];
}

//销毁流媒体上下文

- (void)destroyInstance
{
    [NvsStreamingContext destroyInstance];
}

//开启美颜

- (void)appendBeautyCaptureVideoFx
{
    [self.context appendBeautyCaptureVideoFx];
}

//是否是前置摄像头

- (BOOL)isFrontCamera
{
    return ![self.context isCaptureDeviceBackFacing:0];
}

//切换摄像图头

- (void)switchCamera
{
    if (!_isFront) {
        [self startCapturePreview:0];
        _isFront = YES;
    }
    else {
        [self startCapturePreview:1];
        _isFront = NO;
    }
}

- (void)startFlight
{
    if (_isOpen == NO) {
        [self.context toggleFlash:YES];
        _isOpen = YES;
    }
    else {
        [self.context toggleFlash:NO];
        _isOpen = NO;
    }
}

- (void)stop
{
    [self.context stop];
    [self.context clearCachedResources:YES];
    self.context.delegate = nil;
}

//先将视频保存到沙盒

- (void)saveRecording:(NSString *)tmpPath
{
        //再将视频保存到相册
    UISaveVideoAtPathToSavedPhotosAlbum(tmpPath, self, @selector(video:didFinishSavingWithError:contextInfo:), nil);
}

#pragma mark - Lazy Load

//上下文

- (NvsStreamingContext *)context
{
    if (!_context) {
        _context = [NvsStreamingContext sharedInstance];
        _context.delegate = self;
    }
    return _context;
}

//时间线

- (NvsTimeline *)timeLine
{
    if (!_timeLine) {
        NvsVideoResolution videoEditRes;
        videoEditRes.imageWidth = 720/2;
        videoEditRes.imageHeight = 1280/2;
        videoEditRes.imagePAR = (NvsRational){1, 1};
        NvsRational videoFps = {25, 1};
        NvsAudioResolution audioEditRes;
        audioEditRes.sampleRate = 48000;
        audioEditRes.channelCount = 2;
        audioEditRes.sampleFormat = NvsAudSmpFmt_S16;
        _timeLine = [self.context createTimeline:&videoEditRes videoFps:&videoFps audioEditRes:&audioEditRes];
//        NvsVideoTrack *videoTrack = [_timeLine appendVideoTrack];
        //        NvsVideoTrack *videoTrack = [_timeLine appendVideoTrack];
        //        //在轨道上添加片段。（请自行实现获取手机存储器里视频和图片的代码部分)
        //
        //        NSString* videoUrl = @"file:///var/mobile/Media/DCIM/102APPLE/IMG_2625.MOV";
        //        [videoTrack appendClip:videoUrl];
    }
    return _timeLine;
}

#pragma mark - NvsStreamingContextDelegate

- (void)didCaptureDeviceCapsReady:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集设备准备完成");
}

- (void)didCaptureDevicePreviewResolutionReady:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集设备预览解析度准备完成");
}

- (void)didCaptureDevicePreviewStarted:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集设备预览开始");
}

- (void)didCaptureDeviceError:(unsigned int)captureDeviceIndex errorCode:(int32_t)errorCode
{
    NSLog(@"采集设备错误");
}

/*! \if ENGLISH
 *  \brief
 *  method detailed description
 *  \param sender sender parameter description
 *  \return return value description
 *  \else
 *  \brief 采集设备停止
 *  \param captureDeviceIndex 设备索引
 *  \return 返回值为空
 *  \endif
 */

- (void)didCaptureDeviceStopped:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集设备停止");
}

/*! \if ENGLISH
 *  \brief
 *  method detailed description
 *  \param sender sender parameter description
 *  \return return value description
 *  \else
 *  \brief 采集设备自动对焦完成
 *  \param captureDeviceIndex 设备索引
 *  \param succeeded 对焦是否完成
 *  \return 返回值为空
 *  \endif
 */

- (void)didCaptureDeviceAutoFocusComplete:(unsigned int)captureDeviceIndex succeeded:(BOOL)succeeded
{
    NSLog(@"采集设备自动对焦完成");
}

/*! \if ENGLISH
 *  \brief
 *  method detailed description
 *  \param sender sender parameter description
 *  \return return value description
 *  \else
 *  \brief 采集录制完成
 *  \param captureDeviceIndex 设备索引
 *  \sa didCaptureRecordingError:
 *  \return 返回值为空
 *  \endif
 */

- (void)didCaptureRecordingFinished:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集录制完成");
}

/*! \if ENGLISH
 *  \brief
 *  method detailed description
 *  \param sender sender parameter description
 *  \return return value description
 *  \else
 *  \brief 采集录制失败
 *  \param captureDeviceIndex 设备索引
 *  \return 返回值为空
 *  \endif
 */

- (void)didCaptureRecordingError:(unsigned int)captureDeviceIndex
{
    NSLog(@"采集录制失败");
}

@end

该工具类可以满足利用美摄SDK进行短视频录制的需求，实现了预览、录制等功能。

后记

未完，待续~~

篱笆知秋