如何在 iPad1 iOS SDK 上以编程方式保存视频

Posted 2023-05-07

【中文标题】如何在 iPad1 iOS SDK 上以编程方式保存视频

【英文标题】：how to save video programmatically on iPad1 iOS SDK

【发布时间】：2012-05-01 06:52:14

【问题描述】：

我有一组图像，我将它们转换为电影视频，现在我想知道如何将转换后的视频保存到 ipad。

我可以将转换后的视频保存到 iPad 照片库

NSError *error = nil;

AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:path] fileType:AVFileTypeQuickTimeMovie error:&error];

NSParameterAssert(videoWriter);

NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                               AVVideoCodecH264, AVVideoCodecKey,
                               [NSNumber numberWithInt:size.width], AVVideoWidthKey,
                               [NSNumber numberWithInt:size.height], AVVideoHeightKey,
                               nil];
AVAssetWriterInput* writerInput = [[AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings] retain];


// NSDictionary *bufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey, nil];

AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput sourcePixelBufferAttributes:nil];


NSParameterAssert(writerInput);
NSParameterAssert([videoWriter canAddInput:writerInput]);
[videoWriter addInput:writerInput];

//Start a session:
[videoWriter startWriting];
[videoWriter startSessionAtSourceTime:kCMTimeZero];

CVPixelBufferRef buffer = NULL;

//convert uiimage to CGImage.

CFDataRef imgData = (CFDataRef)[array objectAtIndex:0];
CGDataProviderRef imgDataProvider = CGDataProviderCreateWithCFData (imgData);
CGImageRef image1 = CGImageCreateWithPNGDataProvider(imgDataProvider, NULL, true, kCGRenderingIntentDefault);

buffer = [self pixelBufferFromCGImage:image1];
[adaptor appendPixelBuffer:buffer withPresentationTime:kCMTimeZero];

//Write samples:......

//Finish the session:
[writerInput markAsFinished];
[videoWriter finishWriting];

【问题讨论】：

您将它们转换为视频的格式，基本上可以借助 AVFoundation 或 QTCaptureView API

@Rohan 我使用 AvAssetWriter 转换了它，并用我编写的代码编辑了我的问题

我的问题是如何将转换后的视频保存到 iPad version1 库中

查看此链接***.com/questions/3851294/…

检查也有同样的东西iphonedevsdk.com/forum/iphone-sdk-development/…

【参考方案1】：

试试这个开源组件：-

https://www.cocoacontrols.com/controls/iqprojectvideo

这可能会对您有所帮助。根据您的要求使用它。

【参考方案2】：

试试下面的代码：

 [_operationQueue addOperationWithBlock:^

    NSInteger i = 0;

    NSString *path = [NSTemporaryDirectory() stringByAppendingFormat:@"%d.png",i];
    UIImage *image;

    NSDate *startDate;

    while ((image = [UIImage imageWithContentsOfFile:path]))
    
        while (1)
        
            if (writerInput.readyForMoreMediaData == NO)
            
                sleep(0.01);
                continue;
            
            else
            
                //First time only
                if (buffer == NULL)
                
                    CVPixelBufferPoolCreatePixelBuffer (NULL, adaptor.pixelBufferPool, &buffer);
                    startDate = [_dates objectAtIndex:i];
                

                buffer = [IQProjectVideo pixelBufferFromCGImage:image.CGImage];

                if (buffer)
                
                    if(i<_dates.count)

                    NSDate *currentDate = [_dates objectAtIndex:i];
                    Float64 interval = [currentDate timeIntervalSinceDate:startDate];

                    int32_t timeScale;

                    if (i == 0)
                    
                        timeScale = 1.0/([[_dates objectAtIndex:i+1] timeIntervalSinceDate:currentDate]);
                    
                    else
                    
                        timeScale = 1.0/([currentDate timeIntervalSinceDate:[_dates objectAtIndex:i-1]]);
                    

                    /**/
                    CMTime presentTime=CMTimeMakeWithSeconds(interval, MAX(33, timeScale));
                    //                        NSLog(@"presentTime:%@",(__bridge NSString *)CMTimeCopyDescription(kCFAllocatorDefault, presentTime));


                    if (_progressBlock != NULL)
                    
                        dispatch_sync(dispatch_get_main_queue(), ^
                            _progressBlock((CGFloat)i/(CGFloat)currentIndex);
                        );
                    


                    // append buffer
                    [adaptor appendPixelBuffer:buffer withPresentationTime:presentTime];
                    CVPixelBufferRelease(buffer);
                
                
                break;
            
        

        [[NSFileManager defaultManager] removeItemAtPath:path error:nil];

        path = [NSTemporaryDirectory() stringByAppendingFormat:@"%d.png",++i];
    

    //Finish the session:
    [writerInput markAsFinished];

    if ([videoWriter respondsToSelector:@selector(finishWritingWithCompletionHandler:)])
    
        [videoWriter finishWritingWithCompletionHandler:^
            CVPixelBufferPoolRelease(adaptor.pixelBufferPool);

        ];
    
    else
    
        [videoWriter finishWriting];
        CVPixelBufferPoolRelease(adaptor.pixelBufferPool);
    

    NSDictionary *fileAttrubutes = [[NSFileManager defaultManager] attributesOfItemAtPath:_path error:nil];
    NSDictionary *dictInfo = [NSDictionary dictionaryWithObjectsAndKeys:
                              _path,IQFilePathKey,
                              [fileAttrubutes objectForKey:NSFileSize], IQFileSizeKey,
                              [fileAttrubutes objectForKey:NSFileCreationDate], IQFileCreateDateKey,
                              nil];

    if (_completionBlock != NULL)
    
        dispatch_sync(dispatch_get_main_queue(), ^
            _completionBlock(dictInfo,videoWriter.error);
        );
    

    NSString *openCommand = [NSString stringWithFormat:@"/usr/bin/open \"%@\"", NSTemporaryDirectory()];
    system([openCommand fileSystemRepresentation]);