Updates for subtitles

output.go

@@ -24,6 +24,8 @@ type output struct {
 	vCodec        string
 	vCodecOptions []string
 
+	sCodec string
+
 	format        string
 	formatOptions []string
 
@@ -49,8 +51,8 @@ func (out *output) process(job *transcodeJob) error {
 		job.proc.AppendArgs(out.aCodecOptions...)
 	}
 
-	if out.vCodec == "copy" || out.aCodec == "copy" {
-		job.proc.AppendArgs("-map", "0")
+	if out.sCodec != "" {
+		job.proc.AppendArgs("-c:s", out.sCodec)
 	}
 
 	if out.format != "" {
@@ -114,6 +116,14 @@ func CopyAudioOption() OutputOption {
 	}
 }
 
+// CopySubtitlesOption will set the subtitle codec to copy
+func CopySubtitlesOption() OutputOption {
+	return func(output *output) error {
+		output.sCodec = "copy"
+		return nil
+	}
+}
+
 // CopyOutput sets both the audio and video codecs to copy
 func CopyOutput() OutputOption {
 	return func(output *output) error {

transcode.go

@@ -146,7 +146,11 @@ func (job *transcodeJob) run(cancelCh chan struct{}, doneCh chan struct{}, stder
 
 	job.err = job.proc.Wait()
 	if job.err != nil {
-		job.err = errors.New(strings.Join(job.log[len(job.log)-2:], "\n"))
+		if len(job.log) >= 2 {
+			job.err = errors.New(strings.Join(job.log[len(job.log)-2:], "\n"))
+		} else if len(job.log) == 1 {
+			job.err = errors.New(job.log[0])
+		}
 	}
 }