Nashville [instagram] And iosinstagram with iOS Filter Implementation

Nashville [instagram] And iosinstagram with iOS Filter Implementation

Nashville is one of the most amazing among Instagram's many filters. Its unique milkshake tones give the photos a fairy tale of beauty.
Applicability: Create a romantic and beautiful feeling.
Indeed.
Two input images

Vertex coloring
There are two sets of coordinates
NSString * const kGPUImageTwoInputTextureVertexShaderString = SHADER_STRING

(Attribute vec4 position;
// Input coordinate attribute vec4 inputTextureCoordinate; attribute vec4 rectangle; // output coordinate, with fragment shader varying vec2 textureCoordinate; varying vec2 textureCoordinate2; void main (){
// Tell the fragment shader which pixels I am processing gl_Position = position; textureCoordinate = inputTextureCoordinate. xy; textureCoordinate2 = inputTextureCoordinate2.xy ;});

Segment coloring

NSString *const kFWNashvilleShaderString = SHADER_STRING( precision lowp float;  varying highp vec2 textureCoordinate;  uniform sampler2D inputImageTexture; uniform sampler2D inputImageTexture2;  void main() {     vec3 texel = texture2D(inputImageTexture, textureCoordinate).rgb;     texel = vec3(                  texture2D(inputImageTexture2, vec2(texel.r, .16666)).r,                  texture2D(inputImageTexture2, vec2(texel.g, .5)).g,                  texture2D(inputImageTexture2, vec2(texel.b, .83333)).b);     gl_FragColor = vec4(texel, 1.0); } );

 

Initialization

- (id)init{    if (!(self = [super init]))    {        return nil;    }        UIImage *image = [UIImage imageNamed:@"nashvilleMap.png"];        imageSource = [[GPUImagePicture alloc] initWithImage:image];    FWFilter1 *filter = [[FWFilter1 alloc] init];        [self addFilter:filter];    [imageSource addTarget:filter atTextureLocation:1];    [imageSource processImage];        self.initialFilters = [NSArray arrayWithObjects:filter, nil];    self.terminalFilter = filter;        return self;}

/// FWNashvilleFilter. h // FWMeituApp // Created by hzkmn on 16/1/8. // Copyright©2016 ForrestWoo co,. ltd. All rights reserved. // # import "authorization. h" @ interface FWFilter1: reply @ end @ interface FWNashvilleFilter: GPUImageFilterGroup {GPUImagePicture * imageSource;} @ end

 

/// FWNashvilleFilter. m // FWMeituApp // Created by hzkmn on 16/1/8. // Copyright©2016 ForrestWoo co ,. ltd. all rights reserved. // # import "FWNashvilleFilter. h "NSString * const inline = SHADER_STRING (precision lowp float; varying highp vec2 inline; uniform sampler2D inline; uniform sampler2D inline; void main () {vec3 texel = texture2D (Inline, textureCoordinate ). rgb; texel = vec3 (texture2D (inputImageTexture2, vec2 (te Xel. r ,. 16666 )). r, texture2D (inputImageTexture2, vec2 (texel. g ,. 5 )). g, texture2D (inputImageTexture2, vec2 (texel. B ,. 83333 )). b); gl_FragColor = vec4 (texel, 1.0) ;}); @ implementation FWFilter1-(id) init; {if (! (Self = [super initWithFragmentShaderFromString: kFWNashvilleShaderString]) {return nil;} return self ;}@ end @ implementation FWNashvilleFilter-(id) init {if (! (Self = [super init]) {return nil;} UIImage * image = [UIImage imageNamed: @ "nashvilleMap.png"]; imageSource = [[GPUImagePicture alloc] initWithImage: image]; FWFilter1 * filter = [FWFilter1 alloc] init]; [self addFilter: filter]; [imageSource addTarget: filter atTextureLocation: 1]; [imageSource processImage]; self. initialFilters = [NSArray arrayWithObjects: filter, nil]; self. terminalFilter = filter; return self;} @ end

 

Source image

View the complete project code on github.

 

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