Resize Image in Parallel

resize_parallel.go

package resizeparallel

import (
	"Exercise/ResizeImage/lib/resizer"
	"Exercise/ResizeImage/lib/types"
	"flag"
	"fmt"
	"os"
	"runtime"
	"time"
)

// ResizeParallel - Resize sequentially a file input, to several sizes
func ResizeParallel(input string, sizes []types.Size, maxprocs int) {
	if maxprocs > 0 {
		runtime.GOMAXPROCS(maxprocs)
	}
	start := time.Now()
	if input == "" {
		fmt.Printf("No input file \n")
		flag.Usage()
		os.Exit(0)
	}

	channel := make(chan types.ReturnValue)

	for _, size := range sizes {
		go resizer.ResizeImageNonBlocking(
			input,
			size.Width,
			size.Height,
			channel,
		)
	}

	for i := 0; i < len(sizes); i++ {
		returnValue := <-channel
		if returnValue.Error != nil {
			fmt.Printf("Error happens %v", returnValue.Error)
			os.Exit(0)
		}
		fmt.Printf("\nImage resized %v\n", returnValue.FileName)
	}
	fmt.Println("\nResizeParallel time: ", time.Since(start))
}