Para mi proyecto actual, estoy leyendo la salida principal de la cámara del iPhone. Luego, estoy convirtiendo el pixelbuffer a una textura OpenGL en caché a través del método:CVOpenGLESTextureCacheCreateTextureFromImage. Esto funciona muy bien cuando se procesan marcos de cámara que se utilizan para la vista previa. Probado en diferentes combinaciones con el iPhone 3GS, 4, 4S, iPod Touch (4ª generación) e IOS5, IOS6.

Pero, para la imagen final real, que tiene una resolución muy alta, esto solo funciona en estas combinaciones:

iPhone 3GS + IOS 5.1.1iPhone 4 + IOS 5.1.1iPhone 4S + IOS 6.0iPod Touch (4ª generación) + IOS 5.0

Y esto no funciona para: iPhone 4 + IOS6.

El mensaje de error exacto en la consola:

Failed to create IOSurface image (texture)
2012-10-01 16:24:30.663 GLCameraRipple[676:907] Error at CVOpenGLESTextureCacheCreateTextureFromImage -6683

He aislado este problema cambiando el proyecto GLCameraRipple de Apple. Puedes ver mi versión aquí:http://lab.bitshiftcop.com/iosurface.zip

Así es como agrego la salida fija a la sesión actual:

- (void)setupAVCapture
{
    //-- Create CVOpenGLESTextureCacheRef for optimal CVImageBufferRef to GLES texture conversion.
    CVReturn err = CVOpenGLESTextureCacheCreate(kCFAllocatorDefault, NULL, [EAGLContext currentContext], NULL, &_videoTextureCache);
    if (err) 
    {
        NSLog(@"Error at CVOpenGLESTextureCacheCreate %d", err);
        return;
    }

    //-- Setup Capture Session.
    _session = [[AVCaptureSession alloc] init];
    [_session beginConfiguration];

    //-- Set preset session size.
    [_session setSessionPreset:_sessionPreset];

    //-- Creata a video device and input from that Device.  Add the input to the capture session.
    AVCaptureDevice * videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if(videoDevice == nil)
        assert(0);

    //-- Add the device to the session.
    NSError *error;        
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];
    if(error)
        assert(0);

    [_session addInput:input];

    //-- Create the output for the capture session.
    AVCaptureVideoDataOutput * dataOutput = [[AVCaptureVideoDataOutput alloc] init];
    [dataOutput setAlwaysDiscardsLateVideoFrames:YES]; // Probably want to set this to NO when recording

    //-- Set to YUV420.
    [dataOutput setVideoSettings:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCVPixelFormatType_32BGRA]
                                                             forKey:(id)kCVPixelBufferPixelFormatTypeKey]]; // Necessary for manual preview

    // Set dispatch to be on the main thread so OpenGL can do things with the data
    [dataOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];


    // Add still output
    stillOutput = [[AVCaptureStillImageOutput alloc] init];
    [stillOutput setOutputSettings:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:kCVPixelFormatType_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey]];
    if([_session canAddOutput:stillOutput]) [_session addOutput:stillOutput];

    [_session addOutput:dataOutput];
    [_session commitConfiguration];

    [_session startRunning];
}

Y así es como capturo la salida fija y la proceso:

- (void)capturePhoto
{
    AVCaptureConnection *videoConnection = nil;
    for (AVCaptureConnection *connection in stillOutput.connections) {
        for (AVCaptureInputPort *port in [connection inputPorts]) {
            if ([[port mediaType] isEqual:AVMediaTypeVideo] ) {
                videoConnection = connection;
                break;
            }
        }
        if (videoConnection) { break; }
    }

    [stillOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:
     ^(CMSampleBufferRef imageSampleBuffer, NSError *error) {
         // Process hires image
         [self captureOutput:stillOutput didOutputSampleBuffer:imageSampleBuffer fromConnection:videoConnection];
     }];
}

Así es como se crea la textura:

- (void)captureOutput:(AVCaptureOutput *)captureOutput 
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer 
       fromConnection:(AVCaptureConnection *)connection
{
    CVReturn err;
    CVImageBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
    size_t width = CVPixelBufferGetWidth(pixelBuffer);
    size_t height = CVPixelBufferGetHeight(pixelBuffer);

    if (!_videoTextureCache)
    {
        NSLog(@"No video texture cache");
        return;
    }

    if (_ripple == nil ||
        width != _textureWidth ||
        height != _textureHeight)
    {
        _textureWidth = width;
        _textureHeight = height;

        _ripple = [[RippleModel alloc] initWithScreenWidth:_screenWidth 
                                              screenHeight:_screenHeight
                                                meshFactor:_meshFactor
                                               touchRadius:5
                                              textureWidth:_textureWidth
                                             textureHeight:_textureHeight];

        [self setupBuffers];
    }

    [self cleanUpTextures];

    NSLog(@"%zi x %zi", _textureWidth, _textureHeight);

    // RGBA texture
    glActiveTexture(GL_TEXTURE0);
    err = CVOpenGLESTextureCacheCreateTextureFromImage(kCFAllocatorDefault, 
                                                       _videoTextureCache,
                                                       pixelBuffer,
                                                       NULL,
                                                       GL_TEXTURE_2D,
                                                       GL_RGBA,
                                                       _textureWidth,
                                                       _textureHeight,
                                                       GL_BGRA,
                                                       GL_UNSIGNED_BYTE,
                                                       0,
                                                       &_chromaTexture);
    if (err) 
    {
        NSLog(@"Error at CVOpenGLESTextureCacheCreateTextureFromImage %d", err);
    }

    glBindTexture(CVOpenGLESTextureGetTarget(_chromaTexture), CVOpenGLESTextureGetName(_chromaTexture));
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); 
}

¿Alguna sugerencia para una solución a este problema?