Use copy if we can

manager.go

@@ -38,6 +38,7 @@ type ProbeVideoData struct {
 	Height    int
 	Duration  time.Duration
 	FrameRate int
+	CodecName string
 }
 
 func NewManager(c *Config, path string, id string, close chan string) (*Manager, error) {
@@ -214,7 +215,7 @@ func (m *Manager) ffprobe() error {
 
 		// video
 		"-show_entries", "format=duration",
-		"-show_entries", "stream=duration,width,height,avg_frame_rate",
+		"-show_entries", "stream=duration,width,height,avg_frame_rate,codec_name",
 		"-select_streams", "v", // Video stream only, we're not interested in audio
 
 		"-of", "json",
@@ -240,6 +241,7 @@ func (m *Manager) ffprobe() error {
 			Height    int    `json:"height"`
 			Duration  string `json:"duration"`
 			FrameRate string `json:"avg_frame_rate"`
+			CodecName string `json:"codec_name"`
 		} `json:"streams"`
 		Format struct {
 			Duration string `json:"duration"`
@@ -286,6 +288,7 @@ func (m *Manager) ffprobe() error {
 		Height:    out.Streams[0].Height,
 		Duration:  duration,
 		FrameRate: int(frameRate),
+		CodecName: out.Streams[0].CodecName,
 	}
 
 	return nil

stream.go

@@ -280,10 +280,13 @@ func (s *Stream) transcode(startId int) {
 		}...)
 	}
 
-	// QSV / encoder selection
-	VAAPI := os.Getenv("VAAPI") == "1"
+	// encoder selection
 	CV := "libx264"
-	if VAAPI {
+
+	// no need to transcode h264 streams for max quality
+	if s.quality == "max" && s.m.probe.CodecName == "h264" {
+		CV = "copy"
+	} else if os.Getenv("VAAPI") == "1" {
 		CV = "h264_vaapi"
 		extra := "-hwaccel vaapi -hwaccel_device /dev/dri/renderD128 -hwaccel_output_format vaapi"
 		args = append(args, strings.Split(extra, " ")...)
@@ -298,7 +301,7 @@ func (s *Stream) transcode(startId int) {
 
 	// Scaling for output
 	var scale string
-	if VAAPI {
+	if CV == "h264_vaapi" {
 		scale = fmt.Sprintf("scale_vaapi=w=%d:h=%d:force_original_aspect_ratio=decrease", s.width, s.height)
 	} else if s.width >= s.height {
 		scale = fmt.Sprintf("scale=-2:%d", s.height)
@@ -306,26 +309,26 @@ func (s *Stream) transcode(startId int) {
 		scale = fmt.Sprintf("scale=%d:-2", s.width)
 	}
 
-	// not original (max)
+	// do not scale or set bitrate for full quality
 	if s.quality != "max" {
 		args = append(args, []string{
 			"-vf", scale,
 			"-b:v", fmt.Sprintf("%dk", s.bitrate/1000),
+			"-profile:v", "high",
 		}...)
 	}
 
 	// Output specs
 	args = append(args, []string{
 		"-c:v", CV,
-		"-profile:v", "high",
 	}...)
 
 	// Device specific output args
-	if VAAPI {
+	if CV == "h264_vaapi" {
 		args = append(args, []string{
 			"-low_power", "1",
 		}...)
-	} else {
+	} else if CV == "libx264" {
 		args = append(args, []string{
 			"-preset", "faster",
 			"-level:v", "4.0",