图片转视频

- (void) testCompressionSession

{

    NSArray *imageArr = [NSArray arrayWithObjects:[[UIImage imageNamed:@"114.png"] CGImage],[[UIImage imageNamed:@"114.png"] CGImage],[[UIImage imageNamed:@"placeholderImage.png"] CGImage],[[UIImage imageNamed:@"dfd.png"] CGImage],[[UIImage imageNamed:@"viewbg.png"] CGImage], nil];

    

    CGSize size = CGSizeMake(480, 320);

    

    

    NSString *betaCompressionDirectory = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents/Movie.m4v"];

    

    NSError *error = nil;

    

    unlink([betaCompressionDirectory UTF8String]);

    

    //----initialize compression engine

    AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:betaCompressionDirectory]

                                                           fileType:AVFileTypeQuickTimeMovie

                                                              error:&error];

    NSParameterAssert(videoWriter);

    if(error)

        NSLog(@"error = %@", [error localizedDescription]);

    

    NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:AVVideoCodecH264, AVVideoCodecKey,

                                   [NSNumber numberWithInt:size.width], AVVideoWidthKey,

                                   [NSNumber numberWithInt:size.height], AVVideoHeightKey, nil];

    AVAssetWriterInput *writerInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];

    

    NSDictionary *sourcePixelBufferAttributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys:

                                                           [NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey, nil];

    

    AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput

                                                                                                                     sourcePixelBufferAttributes:sourcePixelBufferAttributesDictionary];

    NSParameterAssert(writerInput);

    NSParameterAssert([videoWriter canAddInput:writerInput]);

    

    if ([videoWriter canAddInput:writerInput])

        NSLog(@"I can add this input");

    else

        NSLog(@"i can't add this input");

    

    [videoWriter addInput:writerInput];

    

    [videoWriter startWriting];

    [videoWriter startSessionAtSourceTime:kCMTimeZero];

    

    //---

    // insert demo debugging code to write the same image repeated as a movie

    

    CGImageRef theImage = [[UIImage imageNamed:@"114.png"] CGImage];

    

    dispatch_queue_t    dispatchQueue = dispatch_queue_create("mediaInputQueue", NULL);

    int __block         frame = 0;

    

    [writerInput requestMediaDataWhenReadyOnQueue:dispatchQueue usingBlock:^{

        while ([writerInput isReadyForMoreMediaData])

        {

            if(++frame >= imageArr.count * 40)

            {

                [writerInput markAsFinished];

                [videoWriter finishWriting];

                

                break;

            }

            int idx = frame/40;

            

            CVPixelBufferRef buffer = (CVPixelBufferRef)[self pixelBufferFromCGImage:(__bridge CGImageRef)([imageArr objectAtIndex:idx]) size:size];

            if (buffer)

            {

                if(![adaptor appendPixelBuffer:buffer withPresentationTime:CMTimeMake(frame, 20)])

                    NSLog(@"FAIL");

                else

                    NSLog(@"Success:%d", frame);

                CFRelease(buffer);

            }

        }

    }];

    

    NSLog(@"outside for loop");

    

}

 

 

- (CVPixelBufferRef )pixelBufferFromCGImage:(CGImageRef)image size:(CGSize)size

{

    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:

                             [NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,

                             [NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey, nil];

    CVPixelBufferRef pxbuffer = NULL;

    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, size.width, size.height, kCVPixelFormatType_32ARGB, (__bridge CFDictionaryRef) options, &pxbuffer);

    // CVReturn status = CVPixelBufferPoolCreatePixelBuffer(NULL, adaptor.pixelBufferPool, &pxbuffer);

    

    NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);

    

    CVPixelBufferLockBaseAddress(pxbuffer, 0);

    void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);

    NSParameterAssert(pxdata != NULL);

    

    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();

    CGContextRef context = CGBitmapContextCreate(pxdata, size.width, size.height, 8, 4*size.width, rgbColorSpace, kCGImageAlphaPremultipliedFirst);

    NSParameterAssert(context);

    

    CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image)), image);

    

    CGColorSpaceRelease(rgbColorSpace);

    CGContextRelease(context);

    

    CVPixelBufferUnlockBaseAddress(pxbuffer, 0);

    

    return pxbuffer;

}

demo