CODEWITHSUNDEEP
iosobjective-cgpuimage
Jon Hocking
Jon Hocking

Reputation: 229

GPUImage failing the CVPixelBufferGetPlaneCount check on iOS

I'm currently bringing a legacy project up from iOS 5/6 to iOS 6/7.

Part of this project involves taking a picture using the GPUImage library, processing it with a crop filter, then optionally adding some saturation and blur effects. I am currently using version 0.1.2 installed via cocoa pods.

The problem I am having is that when I try to capture an image from the camera, I hit the following assert in GPUImageStillCamera.m line 254

if (CVPixelBufferGetPlaneCount(cameraFrame) > 0)
{
  NSAssert(NO, @"Error: no downsampling for YUV input in the framework yet");
}

where cameraFrame is a CVImageBufferRef

I have reproduced the code where this is called and move it to another project, where it works perfectly.

Once I moved this reproduced class back into the main project, I was hitting the assert every time.

Things I've ruled out with my own debugging

This has lead me to believe that perhaps it might be a project setting that I've over looked. Any help or even a pointer in the right direction would be very very welcome. I've spent a good 1-2 days on this now and am still entirely lost!

I've included the stripped down class below which shows the general use.

#import "ViewController.h"
#import "GPUImage.h"
#import "ImageViewController.h"

@interface ViewController ()
@property (nonatomic, strong) IBOutlet GPUImageView *gpuImageView;
@property (nonatomic, strong) GPUImageStillCamera *camera;
@property (nonatomic, strong) GPUImageCropFilter *cropFilter;
@end

@implementation ViewController

- (void)viewDidAppear:(BOOL)animated
{
  [super viewDidAppear:animated];
  [self setupCameraCapture];
}

- (void)setupCameraCapture
{
  if (self.camera) {
    return;
  }

  self.cropFilter = [[GPUImageCropFilter alloc] initWithCropRegion:CGRectMake(0, 0, 1, 0.5625)];

  if ([UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear]) {
    self.camera = [[GPUImageStillCamera alloc] initWithSessionPreset:AVCaptureSessionPresetPhoto cameraPosition:AVCaptureDevicePositionBack];
  }
  else {
    self.camera = [[GPUImageStillCamera alloc] initWithSessionPreset:AVCaptureSessionPresetPhoto cameraPosition:AVCaptureDevicePositionFront];
  }

  self.camera.outputImageOrientation = UIInterfaceOrientationPortrait;

  NSError *error = nil;
  [self.camera.inputCamera lockForConfiguration:&error];
  [self.camera.inputCamera setExposureMode:AVCaptureExposureModeContinuousAutoExposure];
  [self.camera.inputCamera setWhiteBalanceMode:AVCaptureWhiteBalanceModeContinuousAutoWhiteBalance];
  if ([self.camera.inputCamera respondsToSelector:@selector(isLowLightBoostSupported)]) {
    BOOL isSupported = self.camera.inputCamera.isLowLightBoostSupported;
    if (isSupported) {
      [self.camera.inputCamera setAutomaticallyEnablesLowLightBoostWhenAvailable:YES];
    }
  }
  [self.camera.inputCamera unlockForConfiguration];

  [self.camera addTarget:self.cropFilter];
  [self.cropFilter addTarget:self.gpuImageView];
  [self.camera startCameraCapture];
}

- (IBAction)capturePressed:(id)sender
{
  [self.camera capturePhotoAsImageProcessedUpToFilter:self.cropFilter withCompletionHandler:^(UIImage *image, NSError *error) {
    // do something with the image here
  }];
}

@end

Upvotes: 0

Views: 593

Answers (1)

Jon Hocking
Jon Hocking

Reputation: 229

The actual culprit was a swizzled method found by my colleague Marek. Hidden away in the depths of the old codebase. The above code works fine.

Lesson: if you really have to swizzle something, make sure you leave proper documentation for the future devs.

Upvotes: 3

Related Questions