opengl 红蓝切换 上下翻转

opengl  红蓝切换   上下翻转

#pragma mark - #pragma mark Capture Video Methods - (void) testVideoWriter {          //initialize global info     MOVIE_NAME = @"Documents/Movie.mov";     CGSize size = CGSizeMake(1024, 768);     frameLength = CMTimeMake(1, 30);     currentTime = kCMTimeZero;     currentFrame = 0;          NSString *MOVIE_PATH = [NSHomeDirectory() stringByAppendingPathComponent:MOVIE_NAME];     NSError *error = nil;          unlink([MOVIE_PATH UTF8String]);          videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:MOVIE_PATH] fileType:AVFileTypeQuickTimeMovie error:&error];          NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:AVVideoCodecH264, AVVideoCodecKey,                                    [NSNumber numberWithInt:size.width], AVVideoWidthKey,                                    [NSNumber numberWithInt:size.height], AVVideoHeightKey, nil];     writerInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];          //writerInput.expectsMediaDataInRealTime = NO;          NSDictionary *sourcePixelBufferAttributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithInt:kCVPixelFormatType_32BGRA], kCVPixelBufferPixelFormatTypeKey, nil];          adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput                                                                          sourcePixelBufferAttributes:sourcePixelBufferAttributesDictionary];     [adaptor retain];          [videoWriter addInput:writerInput];          [videoWriter startWriting];     [videoWriter startSessionAtSourceTime:kCMTimeZero];          VIDEO_WRITER_IS_READY = true; } - (void) captureScreenVideo {          if (!writerInput.readyForMoreMediaData) {         return;     }          CGSize esize = CGSizeMake(1024, 768);     NSInteger myDataLength = esize.width * esize.height * 4;     GLubyte *buffer = (GLubyte *) malloc(myDataLength);     glReadPixels(0, 0, esize.width, esize.height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);     // swap red and blue     for (int i=0; i         GLubyte b_red = buffer[i];         buffer[i] = buffer[i+2];         buffer[i+2] = b_red;     }     // flip the buffer data     GLubyte *buffer2 = (GLubyte *) malloc(myDataLength);     NSInteger myDataLineLength = esize.width * 4;     for (int i=0; i         memcpy(buffer2+i*myDataLineLength, buffer+((GLuint)esize.height-i-1)*myDataLineLength, myDataLineLength);     }     // copy back flipped data     memcpy(buffer, buffer2, myDataLength);     free(buffer2);          CVPixelBufferRef pixel_buffer = NULL;     CVPixelBufferCreateWithBytes (NULL, esize.width, esize.height, kCVPixelFormatType_32BGRA, buffer, 4 * esize.width, NULL, 0, NULL, &pixel_buffer);          if(![adaptor appendPixelBuffer:pixel_buffer withPresentationTime:currentTime]) {         NSLog(@"FAIL");     } else {         NSLog(@"Success:%d", currentFrame);         currentTime = CMTimeAdd(currentTime, frameLength);     }          free(buffer);     CVPixelBufferRelease(pixel_buffer);     currentFrame++;          if (currentFrame > MAX_FRAMES) {         VIDEO_WRITER_IS_READY = false;         [writerInput markAsFinished];         [videoWriter finishWriting];         [videoWriter release];                  [self moveVideoToSavedPhotos];     } } - (void) moveVideoToSavedPhotos {     ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];     NSString *localVid = [NSHomeDirectory() stringByAppendingPathComponent:MOVIE_NAME];         NSURL* fileURL = [NSURL fileURLWithPath:localVid];          [library writeVideoAtPathToSavedPhotosAlbum:fileURL                                 completionBlock:^(NSURL *assetURL, NSError *error) {                                     if (error) {                                           NSLog(@"%@: Error saving context: %@", [self class], [error localizedDescription]);                                     }                                 }];     [library release]; }