यहाँ उद्देश्य-सी में iOS8 पर नवीनतम कार्य कोड है।
हमें Xcode और iOS8 के लेटेस्ट वर्जन पर काम करने के लिए @ Zoul के जवाब के लिए कई तरह के ट्वीक्स बनाने पड़े। यहां हमारा पूरा कार्य कोड है जो UIImages की एक सरणी लेता है, उन्हें एक .mov फ़ाइल में बनाता है, इसे एक अस्थायी निर्देशिका में सहेजता है, फिर इसे कैमरा रोल में ले जाता है। हमने इस काम को करने के लिए कई अलग-अलग पोस्ट से कोड इकट्ठे किए। हमने उन टिप्पणियों पर प्रकाश डाला है जिन्हें हमें अपनी टिप्पणियों में काम करने के लिए हल करना था।
(1) UIImages का एक संग्रह बनाएँ
[self saveMovieToLibrary]
- (IBAction)saveMovieToLibrary
{
// You just need the height and width of the video here
// For us, our input and output video was 640 height x 480 width
// which is what we get from the iOS front camera
ATHSingleton *singleton = [ATHSingleton singletons];
int height = singleton.screenHeight;
int width = singleton.screenWidth;
// You can save a .mov or a .mp4 file
//NSString *fileNameOut = @"temp.mp4";
NSString *fileNameOut = @"temp.mov";
// We chose to save in the tmp/ directory on the device initially
NSString *directoryOut = @"tmp/";
NSString *outFile = [NSString stringWithFormat:@"%@%@",directoryOut,fileNameOut];
NSString *path = [NSHomeDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:outFile]];
NSURL *videoTempURL = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@%@", NSTemporaryDirectory(), fileNameOut]];
// WARNING: AVAssetWriter does not overwrite files for us, so remove the destination file if it already exists
NSFileManager *fileManager = [NSFileManager defaultManager];
[fileManager removeItemAtPath:[videoTempURL path] error:NULL];
// Create your own array of UIImages
NSMutableArray *images = [NSMutableArray array];
for (int i=0; i<singleton.numberOfScreenshots; i++)
{
// This was our routine that returned a UIImage. Just use your own.
UIImage *image =[self uiimageFromCopyOfPixelBuffersUsingIndex:i];
// We used a routine to write text onto every image
// so we could validate the images were actually being written when testing. This was it below.
image = [self writeToImage:image Text:[NSString stringWithFormat:@"%i",i ]];
[images addObject:image];
}
// If you just want to manually add a few images - here is code you can uncomment
// NSString *path = [NSHomeDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:@"Documents/movie.mp4"]];
// NSArray *images = [[NSArray alloc] initWithObjects:
// [UIImage imageNamed:@"add_ar.png"],
// [UIImage imageNamed:@"add_ja.png"],
// [UIImage imageNamed:@"add_ru.png"],
// [UIImage imageNamed:@"add_ru.png"],
// [UIImage imageNamed:@"add_ar.png"],
// [UIImage imageNamed:@"add_ja.png"],
// [UIImage imageNamed:@"add_ru.png"],
// [UIImage imageNamed:@"add_ar.png"],
// [UIImage imageNamed:@"add_en.png"], nil];
[self writeImageAsMovie:images toPath:path size:CGSizeMake(height, width)];
}
यह मुख्य तरीका है जो आपके एसेटवेटर बनाता है और लेखन के लिए इसमें चित्र जोड़ता है।
(2) एक AVAssetWriter को तार
-(void)writeImageAsMovie:(NSArray *)array toPath:(NSString*)path size:(CGSize)size
{
NSError *error = nil;
// FIRST, start up an AVAssetWriter instance to write your video
// Give it a destination path (for us: tmp/temp.mov)
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];
AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput
sourcePixelBufferAttributes:nil];
NSParameterAssert(writerInput);
NSParameterAssert([videoWriter canAddInput:writerInput]);
[videoWriter addInput:writerInput];
(3) लेखन सत्र प्रारंभ करें (नोट: विधि ऊपर से जारी है)
//Start a SESSION of writing.
// After you start a session, you will keep adding image frames
// until you are complete - then you will tell it you are done.
[videoWriter startWriting];
// This starts your video at time = 0
[videoWriter startSessionAtSourceTime:kCMTimeZero];
CVPixelBufferRef buffer = NULL;
// This was just our utility class to get screen sizes etc.
ATHSingleton *singleton = [ATHSingleton singletons];
int i = 0;
while (1)
{
// Check if the writer is ready for more data, if not, just wait
if(writerInput.readyForMoreMediaData){
CMTime frameTime = CMTimeMake(150, 600);
// CMTime = Value and Timescale.
// Timescale = the number of tics per second you want
// Value is the number of tics
// For us - each frame we add will be 1/4th of a second
// Apple recommend 600 tics per second for video because it is a
// multiple of the standard video rates 24, 30, 60 fps etc.
CMTime lastTime=CMTimeMake(i*150, 600);
CMTime presentTime=CMTimeAdd(lastTime, frameTime);
if (i == 0) {presentTime = CMTimeMake(0, 600);}
// This ensures the first frame starts at 0.
if (i >= [array count])
{
buffer = NULL;
}
else
{
// This command grabs the next UIImage and converts it to a CGImage
buffer = [self pixelBufferFromCGImage:[[array objectAtIndex:i] CGImage]];
}
if (buffer)
{
// Give the CGImage to the AVAssetWriter to add to your video
[adaptor appendPixelBuffer:buffer withPresentationTime:presentTime];
i++;
}
else
{
(4) सत्र समाप्त करें (नोट: विधि ऊपर से जारी है)
//Finish the session:
// This is important to be done exactly in this order
[writerInput markAsFinished];
// WARNING: finishWriting in the solution above is deprecated.
// You now need to give a completion handler.
[videoWriter finishWritingWithCompletionHandler:^{
NSLog(@"Finished writing...checking completion status...");
if (videoWriter.status != AVAssetWriterStatusFailed && videoWriter.status == AVAssetWriterStatusCompleted)
{
NSLog(@"Video writing succeeded.");
// Move video to camera roll
// NOTE: You cannot write directly to the camera roll.
// You must first write to an iOS directory then move it!
NSURL *videoTempURL = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@", path]];
[self saveToCameraRoll:videoTempURL];
} else
{
NSLog(@"Video writing failed: %@", videoWriter.error);
}
}]; // end videoWriter finishWriting Block
CVPixelBufferPoolRelease(adaptor.pixelBufferPool);
NSLog (@"Done");
break;
}
}
}
}
(5) अपने UIImages को CVPixelBufferRef में कनवर्ट करें
यह विधि आपको CV पिक्सेल बफर संदर्भ देगी जो कि एसेटवेयर द्वारा आवश्यक है। यह एक CGImageRef से प्राप्त होता है जो आपको आपके UIImage (ऊपर) से मिलता है।
- (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image
{
// This again was just our utility class for the height & width of the
// incoming video (640 height x 480 width)
ATHSingleton *singleton = [ATHSingleton singletons];
int height = singleton.screenHeight;
int width = singleton.screenWidth;
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,
[NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,
nil];
CVPixelBufferRef pxbuffer = NULL;
CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, width,
height, kCVPixelFormatType_32ARGB, (__bridge CFDictionaryRef) options,
&pxbuffer);
NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
NSParameterAssert(pxdata != NULL);
CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(pxdata, width,
height, 8, 4*width, rgbColorSpace,
kCGImageAlphaNoneSkipFirst);
NSParameterAssert(context);
CGContextConcatCTM(context, CGAffineTransformMakeRotation(0));
CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image),
CGImageGetHeight(image)), image);
CGColorSpaceRelease(rgbColorSpace);
CGContextRelease(context);
CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
return pxbuffer;
}
(6) अपने वीडियो को कैमरा रोल में ले जाएं
क्योंकि AVAssetWriter सीधे कैमरा रोल में नहीं लिख सकता है, यह वीडियो को "tmp / temp.mov" (या जो भी फ़ाइल नाम आपने ऊपर दिया है) से कैमरा रोल में ले जाता है।
- (void) saveToCameraRoll:(NSURL *)srcURL
{
NSLog(@"srcURL: %@", srcURL);
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
ALAssetsLibraryWriteVideoCompletionBlock videoWriteCompletionBlock =
^(NSURL *newURL, NSError *error) {
if (error) {
NSLog( @"Error writing image with metadata to Photo Library: %@", error );
} else {
NSLog( @"Wrote image with metadata to Photo Library %@", newURL.absoluteString);
}
};
if ([library videoAtPathIsCompatibleWithSavedPhotosAlbum:srcURL])
{
[library writeVideoAtPathToSavedPhotosAlbum:srcURL
completionBlock:videoWriteCompletionBlock];
}
}
ऊपर दिए गए ज़ूल का जवाब आप क्या कर रहे हैं की एक अच्छी रूपरेखा देता है। हमने बड़े पैमाने पर इस कोड पर टिप्पणी की ताकि आप देख सकें कि यह कैसे काम कोड का उपयोग करके किया गया था।