Unable to draw CIImage on GLKView after few frames since updated to iOS 10.2?

Question

Using following code in my application which was performing quiet fine to draw a CIImage on a GLKView again and again as recieved from AVCaptureOutput -didOutputSampleBuffer until I was using iOS <= 10.1.*

After updating device to iOS 10.2.1 it has stopped working. I am calling it for few frames the app just crashes with low memory warning. Whereas with iOS 10.1.1 and below I smoothly runs the app even on older device like iPhone 5S.

[_glkView bindDrawable];  

if (self.eaglContext != [EAGLContext currentContext])  
[EAGLContext setCurrentContext:self.eaglContext];  

glClearColor(0.0, 0.0, 0.0, 1.0);  
glClear(GL_COLOR_BUFFER_BIT);  

glEnable(GL_BLEND);  
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);  

if (ciImage) {  
    [_ciContext drawImage:ciImage inRect:gvRect fromRect:dRect];  
}  

[_glkView display];  

This is how I am making the CIImage.

- (CIImage*)ciImageFromPixelBuffer:(CVPixelBufferRef)pixelBuffer ofSampleBuffer:(CMSampleBufferRef)sampleBuffer {
CIImage *croppedImage           = nil;

CFDictionaryRef attachments     = CMCopyDictionaryOfAttachments(kCFAllocatorDefault, sampleBuffer, kCMAttachmentMode_ShouldPropagate);
CIImage *ciImage                = [CIImage imageWithCVPixelBuffer:pixelBuffer options:(NSDictionary *)attachments];

if (attachments)
    CFRelease(attachments);

croppedImage = ciImage;


    CIFilter *scaleFilter = [CIFilter filterWithName:@"CILanczosScaleTransform"];
    [scaleFilter setValue:croppedImage forKey:@"inputImage"];
    [scaleFilter setValue:[NSNumber numberWithFloat:self.zoom_Resize_Factor == 1 ? 0.25 : 0.5] forKey:@"inputScale"];
    [scaleFilter setValue:[NSNumber numberWithFloat:1.0] forKey:@"inputAspectRatio"];
    croppedImage = [scaleFilter valueForKey:@"outputImage"];


    NSDictionary *options = @{(id)kCIImageAutoAdjustRedEye : @(false)};

    NSArray *adjustments = [ciImage autoAdjustmentFiltersWithOptions:options];
    for (CIFilter *filter in adjustments) {
        [filter setValue:croppedImage forKey:kCIInputImageKey];
        croppedImage = filter.outputImage;
    }

CIFilter *selectedFilter = [VideoFilterFactory getFilterWithType:self.selectedFilterType]; //This line needs to be removed from here

croppedImage = [VideoFilterFactory applyFilter:selectedFilter OnImage:croppedImage];

CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

return croppedImage;
}

Here is imgur link http://imgur.com/a/u6Vyo of VM Tracker and OpenGL ES instruments result. Incase it eases to understand. Thanks.

Answer 1

Your GLKView rendering implementation looks fine, the issue seems to be coming from the amount of processing you're doing on PixelBuffer after converting it into CIImage.

Also the Imgur link you shared shows that GLKView is unable to prepare VideoTexture object correctly, most probably due to the memory overload being created in each iteration. You need to optimise this CIFilter Processing.