Convert RGB Image to Grayscale using Java

readme.md

Read the complete article on converting RGB images to grayscale using Java: https://blog.aspose.com/2021/08/06/convert-rgb-images-to-grayscale-in-java/

convert-image-to-binary-fixed.java

// Load an image in an instance of Image
try (Image image = Image.load("aspose-logo.jpg"))
{
    // Cast the image to RasterCachedImage and Check if image is cached                
    RasterCachedImage rasterCachedImage = (RasterCachedImage)image;
    if (!rasterCachedImage.IsCached)
    {
        // Cache image if not already cached
        rasterCachedImage.CacheData();
    }

    // Binarize image with predefined fixed threshold and Save the resultant image                
    rasterCachedImage.binarizeFixed((byte) 100);
    rasterCachedImage.save("BinarizationWithFixedThreshold_out.jpg");
}

convert-image-to-binary-otsu.java

// Load an image in an instance of Image
try (Image image = Image.load("aspose-logo.jpg"))
{
    // Cast the image to RasterCachedImage and Check if image is cached
    RasterCachedImage rasterCachedImage = (RasterCachedImage) image;
    if (!rasterCachedImage.isCached())
    {
        // Cache image if not already cached
        rasterCachedImage.cacheData();
    }
    // Binarize image with Otsu Thresholding
    rasterCachedImage.binarizeOtsu();
  
    // Save the resultant image
    rasterCachedImage.save("BinarizationWithOtsuThreshold_out.jpg");
}

convert-rgb-image-to-grayscale.java

// Load an image in an instance of Image
try (Image image = Image.load("aspose-logo.jpg"))
{
    // Cast the image to RasterCachedImage
    RasterCachedImage rasterCachedImage = (RasterCachedImage) image;
    
    // Check if image is cached
    if (!rasterCachedImage.isCached()) {
        // Cache image if not already cached
        rasterCachedImage.cacheData();
    }
    // Transform image to its grayscale representation
    rasterCachedImage.grayscale();
    
    // Save the resultant image
    rasterCachedImage.save("Grayscaling_out.jpg");
}