All Questions
68 questions
1
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0
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124
views
Fetch specific pixels in the image from GPU to CPU using some technique like Transform feedback
I am working on an iOS OpenGLES 3.0 image filter app which need to read the pixel data from a texture, then loop through entire pixels, extract some pixels with some conditions like brightness over a ...
- 187
2
votes
1
answer
953
views
How to render wide color gamut (Display p3) correctly in OpenGL under IOS
IOS support wide color.
But when render a image in wide color, the image color is not correctly.
In EAGLLayer, there is drawableProperties which can choose the color format, but it doesn't have ...
- 21
0
votes
1
answer
283
views
How to convert `CVOpenGLESTextureCacheRef` to `CVMetalTextureCacheRef`?
I need to convert the following code in GPUImage pod from OpenGL to Metal, is that possible to do that?
CVReturn err = CVOpenGLESTextureCacheCreate(kCFAllocatorDefault, NULL, [self context], NULL, &...
- 2,174
1
vote
0
answers
224
views
How to pass OpenGL Shader 'sampler2d' in GPUImage?
I am writing a custom shader and I want to pass & change sampler2d property in OpenGL Shader in GPUImage at run time.
varying highp vec2 centerLocation;
varying highp float pointSpacing;
...
- 44
3
votes
1
answer
2k
views
How to convert UIImage to CVPixelBufferRef using YUV color space?
I am doing video recording. I need to snapshoot a view to a UIImage, and then convert it to CVPixelBufferRef. And it work fine with RGBA color space. But the CVPixelBufferRef I need should be with YUV ...
- 89
2
votes
1
answer
117
views
OpenGL-ES: selective blending
I'm using GPUImage's corner detector for extracting corners from camera captured frames. I'd like to render sparkles at the corners coordinates. When I've got the corners coordinates I pass it to my ...
- 301
3
votes
0
answers
440
views
GPUImage2: passing gl texture to shader
I'm trying to modify GPUImage2 Crosshair generator to replace default crosshairs with gl texture made of UIImage, my image is 128x128 png file.
I'm using GPUImage2 PictureInput for converting UIImage ...
- 301
0
votes
1
answer
585
views
How to integrate ARKit into GPUImage render with SCNRender?
The graph is below:
ARFrame -> 3DModelFilter(SCNScene + SCNRender) -> OtherFilters -> GPUImageView.
Load 3D model:
NSError* error;
SCNScene* scene =[SCNScene sceneWithURL:url options:nil error:&...
- 65
25
votes
3
answers
5k
views
iOS 11 beta 4 presentRenderbuffer crash
My app crashes on iOS 11 beta 4 (15A5327g) when [EAGLContext presentRenderbuffer:] method is called. It happens only when I debugging in Xcode. When I launch app manually it doesn't crashed. On ...
- 1,736
0
votes
1
answer
209
views
GPUImage - Custom Histogram Generator
I'm trying to use GPUImage to implement a histogram into my app. The example project on the GPUImage github called FilterShowcase comes with a good histogram generator, but due to the UI design of the ...
- 959
3
votes
0
answers
451
views
Add sunflare kind of lighting effect on image
I am looking for sunflare kind of lighting effect on Image. In my case light source is bulb instead of Sun. And I understand that changing light source changes rays effect and even different type of ...
- 1,243
1
vote
1
answer
749
views
GPUImage Histogram Equalization
I would like to use GPUImage's Histogram Equalization filter (link to .h) (link to .m) for a camera app. I'd like to use it in real time and present it as an option to be applied on the live camera ...
- 159
-1
votes
1
answer
130
views
Incorrect when using openGL to show GPUImageOutput's BRGA data, 1920*1080
For newcomer to OpengGL, this accident always has something wrong with imageWidth.
GPUImageOutput's data size isn't equal to image.width* image.height * bitsPerPixel. In some code, you may see that ...
- 149
1
vote
2
answers
2k
views
GPUImage Lookup Filter - creating a color depth greater than 512² colors
GPUImage's LookupFilter uses an RGB pixel map that's 512x512. When the filter executes, it creates a comparison between a modified version of this image with the original, and extrapolates an image ...
- 73.3k
0
votes
1
answer
681
views
iOS - How to create custom GPUImageFilters with OpenGLES
I'd like to know how to create custom filters for GPUImage. Right now I can create a sepia custom filter from this code(this was provided by Brad Larson on GitHub as an example):
varying highp vec2 ...
- 369