media_segment_extractor.go

// media_segment_extractor
// primarily generated by ChatGPT 4o
// with edits by Mike Quentel

package main

import (
	"flag"
	"fmt"
	"github.com/u2takey/ffmpeg-go"
	"log"
	"path/filepath"
)

func main() {
	inputFile := flag.String("input", "", "Input media file path (mp4 or mp3)")
	outputFile := flag.String("output", "", "Output media file path (mp4 or mp3)")
	startMark := flag.String("start", "00:00:00", "Start mark (format: HH:MM:SS)")
	duration := flag.String("duration", "00:00:30", "Duration (format: HH:MM:SS)")
	stripAudioFlag := flag.Bool("strip-audio", false, "Strip audio from input mp4 file")
	addAudioFlag := flag.Bool("add-audio", false, "Add mp3 audio to input mp4 file")
	audioFile := flag.String("audio", "", "Input mp3 audio file to add to mp4")

	flag.Parse()

	if *inputFile == "" || *outputFile == "" {
		flag.Usage()
		log.Fatal("input and output file paths are required")
	}

	inputExt := filepath.Ext(*inputFile)
	outputExt := filepath.Ext(*outputFile)

	if inputExt != outputExt {
		log.Fatal("Input and output file extensions must match and be either .mp4 or .mp3")
	}

	if inputExt != ".mp4" && inputExt != ".mp3" {
		log.Fatal("Unsupported file extension. Only .mp4 and .mp3 are supported")
	}

	if *stripAudioFlag {
		if inputExt != ".mp4" {
			log.Fatal("strip-audio option is only supported for .mp4 files")
		}
		fmt.Printf("Stripping audio from %s to %s\n", *inputFile, *outputFile)
		err := stripAudio(*inputFile, *outputFile)
		if err != nil {
			log.Fatal(err)
		}
		log.Println("Audio stripped successfully.")
		return
	}
	if *addAudioFlag {
		if inputExt != ".mp4" || filepath.Ext(*audioFile) != ".mp3" {
			log.Fatal("add-audio option requires an input mp4 file and an mp3 audio file")
		}
		fmt.Printf("Adding audio from %s to %s and saving as %s\n", *audioFile, *inputFile, *outputFile)
		err := addAudioToVideo(*inputFile, *audioFile, *outputFile)
		if err != nil {
			log.Fatal(err)
		}
		log.Println("Audio added successfully.")
		return
	}
	fmt.Printf("Extracting segment from %s to %s, starting at %s, for duration %s\n", *inputFile, *outputFile, *startMark, *duration)

	err := ffmpeg_go.Input(*inputFile, ffmpeg_go.KwArgs{"ss": *startMark}).Output(*outputFile, ffmpeg_go.KwArgs{"t": *duration}).Run()
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Media segment extracted successfully.")
}
func stripAudio(inputFile, outputFile string) error {
	err := ffmpeg_go.Input(inputFile).Output(outputFile, ffmpeg_go.KwArgs{"an": ""}).Run()
	return err
}
func addAudioToVideo(inputVideo, inputAudio, outputVideo string) error {
	videoStream := ffmpeg_go.Input(inputVideo)
	audioStream := ffmpeg_go.Input(inputAudio)
	err := ffmpeg_go.Output([]*ffmpeg_go.Stream{videoStream, audioStream}, outputVideo, ffmpeg_go.KwArgs{"c:v": "copy", "c:a": "aac", "strict": "experimental"}).Run()
	return err
}