Auto Threshold Example

#include <stdio.h>  
#include <stdlib.h>  
  
#define STB_IMAGE_IMPLEMENTATION  
#include "stb_image/stb_image.h"  
#define STB_IMAGE_WRITE_IMPLEMENTATION  
#include "stb_image/stb_image_write.h"  
  
int main(void) {  
    int width, height, channels;  
    unsigned char* inputImage = stbi_load("test.jpg", &width, &height, &channels, 0);  
    if (inputImage) {  
        unsigned char* outputImage = (unsigned char*)calloc(width * channels * height * sizeof(unsigned char), 1);  
        if (outputImage) {  
  
            int stride = width * channels;  
  
            OC_STATUS status;
 
            // input expects a single channel image
            status = ocularGrayscaleFilter(inputImage, inputImage, width, height, stride);
            if (status == OC_STATUS_OK) {
                // methods are defined under OcAutoThresholdMethod in "lib/ocular.h"
                status = ocularAutoThreshold(inputImage, outputImage, width, height, width, OC_AUTO_THRESHOLD_OTSU);  // single channel, so stride = width
                if (status == OC_STATUS_OK) {
                    channels = 1;  
                    stbi_write_jpg("test_out.jpg", width, height, channels, outputImage, 100);  
                }
            }
        }  
        free(outputImage);  
    }  
  
    stbi_image_free(inputImage);  
}

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