Handle non resize transcode (#755)

transcoder/src/filestream.go

@@ -91,8 +91,8 @@ func (fs *FileStream) GetMaster() string {
 	master += "\n"
 
 	// codec is the prefix + the level, the level is not part of the codec we want to compare for the same_codec check bellow
-	transmux_prefix := "avc1.6400"
-	transmux_codec := transmux_prefix + "28"
+	transcode_prefix := "avc1.6400"
+	transcode_codec := transcode_prefix + "28"
 	audio_codec := "mp4a.40.2"
 
 	var def_video *Video
@@ -108,10 +108,15 @@ func (fs *FileStream) GetMaster() string {
 
 	if def_video != nil {
 		qualities := Filter(Qualities, func(quality Quality) bool {
-			same_codec := def_video.MimeCodec != nil && strings.HasPrefix(*def_video.MimeCodec, transmux_prefix)
-			return quality.Height() < def_video.Height ||
-				(quality.Height() == def_video.Height && !same_codec)
+			return quality.Height() < def_video.Height
 		})
+		transcode_count := len(qualities)
+
+		// NoResize is the same idea as Original but we change the codec.
+		// This is only needed when the original's codec is different from what we would transcode it to.
+		if def_video.MimeCodec == nil || !strings.HasPrefix(*def_video.MimeCodec, transcode_prefix) {
+			qualities = append(qualities, NoResize)
+		}
 		qualities = append(qualities, Original)
 
 		for _, quality := range qualities {
@@ -137,34 +142,31 @@ func (fs *FileStream) GetMaster() string {
 		}
 		master += "\n"
 
-		// original stream
-		{
-			bitrate := float64(def_video.Bitrate)
-			master += "#EXT-X-STREAM-INF:"
-			master += fmt.Sprintf("AVERAGE-BANDWIDTH=%d,", int(math.Min(bitrate*0.8, float64(def_video.Quality().AverageBitrate()))))
-			master += fmt.Sprintf("BANDWIDTH=%d,", int(math.Min(bitrate, float64(def_video.Quality().MaxBitrate()))))
-			master += fmt.Sprintf("RESOLUTION=%dx%d,", def_video.Width, def_video.Height)
-			if def_video.MimeCodec != nil {
-				master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{*def_video.MimeCodec, audio_codec}, ","))
-			}
-			master += "AUDIO=\"audio\","
-			master += "CLOSED-CAPTIONS=NONE\n"
-			master += fmt.Sprintf("%d/%s/index.m3u8\n", def_video.Index, Original)
-		}
-
 		aspectRatio := float32(def_video.Width) / float32(def_video.Height)
-
 		for i, quality := range qualities {
-			if i == len(qualities)-1 {
-				// skip the original stream that already got handled
+			if i >= transcode_count {
+				// original & noresize streams
+				bitrate := float64(def_video.Bitrate)
+				master += "#EXT-X-STREAM-INF:"
+				master += fmt.Sprintf("AVERAGE-BANDWIDTH=%d,", int(math.Min(bitrate*0.8, float64(def_video.Quality().AverageBitrate()))))
+				master += fmt.Sprintf("BANDWIDTH=%d,", int(math.Min(bitrate, float64(def_video.Quality().MaxBitrate()))))
+				master += fmt.Sprintf("RESOLUTION=%dx%d,", def_video.Width, def_video.Height)
+				if quality != Original {
+					master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{transcode_codec, audio_codec}, ","))
+				} else if def_video.MimeCodec != nil {
+					master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{*def_video.MimeCodec, audio_codec}, ","))
+				}
+				master += "AUDIO=\"audio\","
+				master += "CLOSED-CAPTIONS=NONE\n"
+				master += fmt.Sprintf("%d/%s/index.m3u8\n", def_video.Index, quality)
 				continue
 			}
 
 			master += "#EXT-X-STREAM-INF:"
 			master += fmt.Sprintf("AVERAGE-BANDWIDTH=%d,", quality.AverageBitrate())
 			master += fmt.Sprintf("BANDWIDTH=%d,", quality.MaxBitrate())
 			master += fmt.Sprintf("RESOLUTION=%dx%d,", int(aspectRatio*float32(quality.Height())+0.5), quality.Height())
-			master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{transmux_codec, audio_codec}, ","))
+			master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{transcode_codec, audio_codec}, ","))
 			master += "AUDIO=\"audio\","
 			master += "CLOSED-CAPTIONS=NONE\n"
 			master += fmt.Sprintf("%d/%s/index.m3u8\n", def_video.Index, quality)

transcoder/src/quality.go

@@ -17,6 +17,7 @@ const (
 	P1440    Quality = "1440p"
 	P4k      Quality = "4k"
 	P8k      Quality = "8k"
+	NoResize Quality = "transcode"
 	Original Quality = "original"
 )
 
@@ -27,6 +28,9 @@ func QualityFromString(str string) (Quality, error) {
 	if str == string(Original) {
 		return Original, nil
 	}
+	if str == string(NoResize) {
+		return NoResize, nil
+	}
 
 	for _, quality := range Qualities {
 		if string(quality) == str {

transcoder/src/videostream.go

@@ -71,16 +71,30 @@ func (vs *VideoStream) getTranscodeArgs(segments string) []string {
 	}
 
 	args = append(args, Settings.HwAccel.EncodeFlags...)
-	width := int32(float64(vs.quality.Height()) / float64(vs.video.Height) * float64(vs.video.Width))
-	// force a width that is a multiple of two else some apps behave badly.
-	width = closestMultiple(width, 2)
+
+	quality := vs.quality
+	if vs.quality != NoResize {
+		width := int32(float64(vs.quality.Height()) / float64(vs.video.Height) * float64(vs.video.Width))
+		// force a width that is a multiple of two else some apps behave badly.
+		width = closestMultiple(width, 2)
+		args = append(args,
+			"-vf", fmt.Sprintf(Settings.HwAccel.ScaleFilter, width, vs.quality.Height()),
+		)
+	} else {
+		// NoResize doesn't have bitrate info, fallback to a know quality higher or equal.
+		for _, q := range Qualities {
+			if q.Height() >= vs.video.Height {
+				quality = q
+				break
+			}
+		}
+	}
 	args = append(args,
-		"-vf", fmt.Sprintf(Settings.HwAccel.ScaleFilter, width, vs.quality.Height()),
 		// Even less sure but bufsize are 5x the avergae bitrate since the average bitrate is only
 		// useful for hls segments.
-		"-bufsize", fmt.Sprint(vs.quality.MaxBitrate()*5),
-		"-b:v", fmt.Sprint(vs.quality.AverageBitrate()),
-		"-maxrate", fmt.Sprint(vs.quality.MaxBitrate()),
+		"-bufsize", fmt.Sprint(quality.MaxBitrate()*5),
+		"-b:v", fmt.Sprint(quality.AverageBitrate()),
+		"-maxrate", fmt.Sprint(quality.MaxBitrate()),
 		// Force segments to be split exactly on keyframes (only works when transcoding)
 		// forced-idr is needed to force keyframes to be an idr-frame (by default it can be any i frames)
 		// without this option, some hardware encoders uses others i-frames and the -f segment can't cut at them.