Golang 開発: 効率的な画像処理アルゴリズムの実装

import (
    "image"
    "image/jpeg"
    "os"
)

func loadImageFromFile(filename string) (image.Image, error) {
    file, err := os.Open(filename)
    if err != nil {
        return nil, err
    }
    defer file.Close()

    img, _, err := image.Decode(file)
    if err != nil {
        return nil, err
    }

    return img, nil
}

func saveImageToFile(filename string, img image.Image) error {
    file, err := os.Create(filename)
    if err != nil {
        return err
    }
    defer file.Close()

    err = jpeg.Encode(file, img, nil)
    if err != nil {
        return err
    }

    return nil
}

import (
    "image"
    "image/color"
)

func adjustBrightness(img image.Image, delta int) image.Image {
    bounds := img.Bounds()
    width, height := bounds.Dx(), bounds.Dy()

    newImage := image.NewRGBA(bounds)

    for y := 0; y < height; y++ {
        for x := 0; x < width; x++ {
            oldColor := img.At(x, y)
            r, g, b, _ := oldColor.RGBA()
            newR := uint8(int(r>>8) + delta)
            newG := uint8(int(g>>8) + delta)
            newB := uint8(int(b>>8) + delta)
            newColor := color.RGBA{newR, newG, newB, 255}
            newImage.Set(x, y, newColor)
        }
    }

    return newImage
}

func resizeImage(img image.Image, newWidth, newHeight int) image.Image {
    bounds := img.Bounds()
    width, height := bounds.Dx(), bounds.Dy()

    scaleX := float64(width) / float64(newWidth)
    scaleY := float64(height) / float64(newHeight)

    newImage := image.NewRGBA(image.Rect(0, 0, newWidth, newHeight))

    for y := 0; y < newHeight; y++ {
        for x := 0; x < newWidth; x++ {
            newX := int(float64(x) * scaleX)
            newY := int(float64(y) * scaleY)
            newColor := img.At(newX, newY)
            newImage.Set(x, y, newColor)
        }
    }

    return newImage
}

func main() {
    // 读取图像
    img, err := loadImageFromFile("input.jpg")
    if err != nil {
        fmt.Println("Failed to read image:", err)
        return
    }

    // 调整亮度
    delta := 50
    newImg := adjustBrightness(img, delta)

    // 保存图像
    err = saveImageToFile("output.jpg", newImg)
    if err != nil {
        fmt.Println("Failed to save image:", err)
        return
    }
}