goptimize/main.go
2019-08-03 00:46:32 +12:00

119 lines
3.1 KiB
Go

package main
import (
"flag"
"fmt"
"os"
"os/exec"
"regexp"
"strconv"
)
var (
quality int
maxWidth int
maxHeight int
outputDir string
preserveModificationTimes bool
jpegoptim string
jpegtran string
optipng string
pngquant string
gifsicle string
)
func main() {
// set the default help
flag.Usage = func() {
fmt.Println("Goptimize - downscales and optimizes images")
fmt.Printf("\nUsage: %s [options] <images>\n", os.Args[0])
fmt.Println("\nOptions:")
flag.PrintDefaults()
fmt.Println("\nExamples:")
fmt.Printf(" %s image.png\n", os.Args[0])
fmt.Printf(" %s -m 800x800 *.jpg\n", os.Args[0])
fmt.Printf(" %s -o out/ -q 90 -m 1600x1600 *.jpg\n", os.Args[0])
fmt.Println("\nDetected optimizers:")
if err := displayDelectedOptimizer("jpegtran ", jpegtran); err != nil {
displayDelectedOptimizer("jpegoptim", jpegoptim)
}
displayDelectedOptimizer("optipng ", optipng)
displayDelectedOptimizer("pngquant ", pngquant)
displayDelectedOptimizer("gifsicle ", gifsicle)
}
var maxSizes string
flag.IntVar(&quality, "q", 75, "quality - JPEG only")
flag.StringVar(&outputDir, "o", "", "output directory (default overwrites original)")
flag.BoolVar(&preserveModificationTimes, "p", true, "preserve file modification times")
flag.StringVar(&maxSizes, "m", "", "downscale to a maximum width & height in pixels (<width>x<height>)")
// third-party optimizers
flag.StringVar(&gifsicle, "gifsicle", "gifsicle", "gifsicle binary")
flag.StringVar(&jpegoptim, "jpegoptim", "jpegoptim", "jpegoptim binary")
flag.StringVar(&jpegtran, "jpegtran", "jpegtran", "jpegtran binary")
flag.StringVar(&optipng, "optipng", "optipng", "optipng binary")
flag.StringVar(&pngquant, "pngquant", "pngquant", "pngquant binary")
// parse flags
flag.Parse()
// detect optimizer paths
gifsicle, _ = exec.LookPath(gifsicle)
jpegoptim, _ = exec.LookPath(jpegoptim)
jpegtran, _ = exec.LookPath(jpegtran)
optipng, _ = exec.LookPath(optipng)
pngquant, _ = exec.LookPath(pngquant)
if len(flag.Args()) < 1 {
flag.Usage()
return
}
if maxSizes != "" {
// calculate max sizes from arg[0]
r := regexp.MustCompile(`^(\d+)(x|X|\*|:)(\d+)$`)
matches := r.FindStringSubmatch(maxSizes)
if len(matches) != 4 {
flag.Usage()
return
}
maxWidth, _ = strconv.Atoi(matches[1])
maxHeight, _ = strconv.Atoi(matches[3])
}
// parse arguments
args := flag.Args()
if outputDir != "" {
// ensure the output directory exists
if _, err := os.Stat(outputDir); os.IsNotExist(err) {
err := os.MkdirAll(outputDir, os.ModePerm)
if err != nil {
fmt.Printf("Cannot create output directory: %s\n", outputDir)
return
}
}
}
for _, img := range args {
Goptimize(img)
}
}
// displayDelectedOptimizer prints whether the optimizer was found
func displayDelectedOptimizer(name, bin string) error {
exe, err := exec.LookPath(bin)
if err != nil {
// fmt.Printf(" - %s: [undetected]\n", name)
return err
}
fmt.Printf(" - %s: %s\n", name, exe)
return nil
}