Check version of ffmpeg. Closes #587

config/verifyInstall.go

@@ -4,6 +4,10 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"os/exec"
+	"strings"
+
+	"golang.org/x/mod/semver"
 )
 
 // verifyFFMpegPath verifies that the path exists, is a file, and is executable.
@@ -28,5 +32,22 @@ func verifyFFMpegPath(path string) error {
 		return errors.New("ffmpeg path is not executable")
 	}
 
+	suggestedVersion := "v4.1.5"
+	cmd := exec.Command(path)
+	out, err := cmd.CombinedOutput()
+
+	response := string(out)
+	if response == "" {
+		fmt.Println(err)
+		return fmt.Errorf("unable to determine the version of your ffmpeg installation at %s. you may experience issues with video.", path)
+	}
+
+	responseComponents := strings.Split(response, " ")
+	fullVersionString := responseComponents[2]
+	versionString := "v" + strings.Split(fullVersionString, "-")[0]
+	if !semver.IsValid(versionString) || semver.Compare(versionString, suggestedVersion) == -1 {
+		return fmt.Errorf("your %s version of ffmpeg at %s may be older than the suggested version of %s. you may experience issues with video.", versionString, path, suggestedVersion)
+	}
+
 	return nil
 }