Wie CVPixelBufferPool in Verbindung mit AVAssetWriterInputPixelBufferAdaptor in iPhone zu benutzen?
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26-09-2019 - |
Frage
Ich habe erfolgreich erstellt Video von Bildern des folgenden Code
mit-(void)writeImageAsMovie:(NSArray *)array toPath:(NSString*)path size:(CGSize)size duration:(int)duration
{
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];
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;
buffer = [self pixelBufferFromCGImage:[[array objectAtIndex:0] CGImage]];
[adaptor appendPixelBuffer:buffer withPresentationTime:kCMTimeZero];
//Write samples:
for (int i = 0;i<[array count]; i++)
{
if([writerInput isReadyForMoreMediaData])
{
NSLog(@"inside for loop %d",i);
CMTime frameTime = CMTimeMake(1, 20);
CMTime lastTime=CMTimeMake(i, 20); //i is from 0 to 24 of the loop above
CMTime presentTime=CMTimeAdd(lastTime, frameTime);
buffer = [self pixelBufferFromCGImage:[[array objectAtIndex:i] CGImage]];
[adaptor appendPixelBuffer:buffer withPresentationTime:presentTime];
}
else
{
NSLog(@"error");
i--;
}
}
NSLog(@"outside for loop");
//Finish the session:
[writerInput markAsFinished];
[videoWriter finishWriting];
}
Hier habe ich verwendet CVPixelBufferRef
. Statt dessen möchte ich die CVPixelBufferPoolRef
in Verbindung mit AVAssetWriterInputPixelBufferAdaptor
verwenden.
Kann jemand ein Beispiel geben, die ich debuggen und verwenden kann?
Lösung
Sie passieren Null ‚sourcePixelBufferAttributes‘, wegen der der Pixelpufferpool wird nicht erstellt bekommen:
AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput sourcePixelBufferAttributes:nil];
Stattdessen einige Attribute passieren, zum Beispiel:
NSDictionary *bufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey, nil];
Dann können Sie den Pool der Pixelpuffer zu schaffen, wie:
CVPixelBufferPoolCreatePixelBuffer (NULL, adaptor.pixelBufferPool, &pixelBuffer);
Andere Tipps
@Atulkumar V. Jain: great! Glück ^^ @ Brian: Sie rechts Dank sind, korrigiere ich es, und ich bin immer daran arbeiten jetzt hier ist der Arbeitscode (wenn jemand anderes Bedürfnis es :-))
CVPixelBufferRef buffer = NULL;
buffer = [self pixelBufferFromCGImage:[[imagesArray objectAtIndex:0] CGImage]];
CVPixelBufferPoolCreatePixelBuffer (NULL, adaptor_.pixelBufferPool, &buffer);
[adaptor_ appendPixelBuffer:buffer withPresentationTime:kCMTimeZero];
__block UInt64 convertedByteCount = 0;
dispatch_queue_t mediaInputQueue = dispatch_queue_create("mediaInputQueue", NULL);
static int i = 1;
int frameNumber = [imagesArray count];
[writerInput requestMediaDataWhenReadyOnQueue:mediaInputQueue usingBlock:^{
while (1){
if (i == frameNumber) {
break;
}
if ([writerInput isReadyForMoreMediaData]) {
CVPixelBufferRef sampleBuffer = [self pixelBufferFromCGImage:[[imagesArray objectAtIndex:i] CGImage]];
NSLog(@"inside for loop %d",i);
CMTime frameTime = CMTimeMake(1, 20);
CMTime lastTime=CMTimeMake(i, 20); //i is from 0 to 19 of the loop above
CMTime presentTime=CMTimeAdd(lastTime, frameTime);
if (sampleBuffer) {
[adaptor_ appendPixelBuffer:sampleBuffer withPresentationTime:presentTime];
i++;
CFRelease(sampleBuffer);
} else {
break;
}
}
}
NSLog (@"done");
[writerInput markAsFinished];
[videoWriter finishWriting];
CVPixelBufferPoolRelease(adaptor_.pixelBufferPool);
[videoWriter release];
[writerInput release];
[imagesArray removeAllObjects];
}];
Anstelle von "für" diesen Code verwenden:
dispatch_queue_t mediaInputQueue = dispatch_queue_create("mediaInputQueue", NULL);
[writerInput requestMediaDataWhenReadyOnQueue:mediaInputQueue usingBlock:^{
CVPixelBufferRef buffer = NULL;
buffer = [self pixelBufferFromCGImage:[[array objectAtIndex:0] CGImage]];
CVPixelBufferPoolCreatePixelBuffer (NULL, adaptor.pixelBufferPool, &buffer);
[adaptor appendPixelBuffer:buffer withPresentationTime:kCMTimeZero];
int i = 1;
while (writerInput.readyForMoreMediaData) {
NSLog(@"inside for loop %d",i);
CMTime frameTime = CMTimeMake(1, 20);
CMTime lastTime=CMTimeMake(i, 20); //i is from 0 to 19 of the loop above
CMTime presentTime=CMTimeAdd(lastTime, frameTime);
if (i >= [array count]) {
buffer = NULL;
}else {
buffer = [self pixelBufferFromCGImage:[[array objectAtIndex:i] CGImage]];
}
//CVBufferRetain(buffer);
if (buffer) {
// append buffer
[adaptor appendPixelBuffer:buffer withPresentationTime:presentTime];
i++;
} else {
// done!
//Finish the session:
[writerInput markAsFinished];
[videoWriter finishWriting];
CVPixelBufferPoolRelease(adaptor.pixelBufferPool);
[videoWriter release];
[writerInput release];
NSLog (@"Done");
[imageArray removeAllObjects];
break;
}
}
}];
Ich habe sie alle Arbeiten!
Hier ist der Beispielcode Link: git@github.com: RudyAramayo / AVAssetWriterInputPixelBufferAdaptorSample.git
Hier ist der Code, den Sie brauchen:
- (void) testCompressionSession
{
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:@"Lotus.png"] CGImage];
dispatch_queue_t dispatchQueue = dispatch_queue_create("mediaInputQueue", NULL);
int __block frame = 0;
[writerInput requestMediaDataWhenReadyOnQueue:dispatchQueue usingBlock:^{
while ([writerInput isReadyForMoreMediaData])
{
if(++frame >= 120)
{
[writerInput markAsFinished];
[videoWriter finishWriting];
[videoWriter release];
break;
}
CVPixelBufferRef buffer = (CVPixelBufferRef)[self pixelBufferFromCGImage:theImage 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, (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;
}