Change SimpleVideoFilter Demo to allow all orientations.
Fix PortraitUpsideDown rotation on the back camera.

The back camera is natively landscape left, therefore upside down is a left rotation.
Added kGPUImageRotate180.

This is needed for the back facing camera on landscape right, since the back camera is left facing landscape.

NOTE: Since a 180 rotation is a flip vert and a flip horz, and both of those are marked as broken in GPUImageCropFilter's -calculateCropTextureCoordinates, so is the additional block to handle rotate180.
Fix front facing camera.
Added method to get the targets from a GPUImageOutput
Added an image buffet filter that delays frames, allowing for comparative processing of sequential frames. There are some slight issues with timing on the blends that I still need to fix.
Merge pull request #226 from acoomans/master

Added method to get the targets from a GPUImageOutput
Texel distances should be set properly for rotated images in a couple of filters now.
Fixed the GPUImageMaskFilter.
Added ability to enable/disabled GPUImageOutputs - fast way to turn them on or off. Replaced all references to self in blocks with __unsafe_unretained __typeof__(self) weakSelf = self; Added method to GPUImageStillCamera to take a photo and retrieve the CMSampleBufferRef directly. However, I left this method commented out, as to use it you have to have the camera pixel format in its native setting, which is incompatible with GPUImage.
Merge pull request #238 from iSkythe/master

Ability to enable/disable GPUImageOutputs. Replaced all references to self in blocks with __unsafe_unretained self. Added method to retrieve the CMSampleBufferRef directly from GPUImageStillCamera
Tweaked some of the weak self references to avoid compiler errors.
Added a filter to adjust the incoming opacity of images.
Merge pull request #201 from Philippe23/video-orientation

Fixes for video orientations & mirroring.
Added a compiler define to check whether this is on the Simulator, disable the texture caches if so. This should enable limited use with the Simulator.
Sphere refraction filter is now functional.
Chroma key blend now respects alpha channels.
Made significant changes to the internal architecture of two-input filters, which should fix many bugs. You no longer need to set targetToIgnoreForUpdates in almost all cases.
Fixed a resize bug with GPUImageView, an infinite loop with GPUImageTwoInputFilter, and filter resizing issues with GPUImageCropFilter.
Fixed a leak with resized still images.