diff --git a/transcoder/src/filestream.go b/transcoder/src/filestream.go
index 3cd17901..555e573f 100644
--- a/transcoder/src/filestream.go
+++ b/transcoder/src/filestream.go
@@ -1,6 +1,7 @@
 package src
 
 import (
+	"fmt"
 	"math"
 	"os/exec"
 	"strconv"
@@ -11,19 +12,37 @@ type FileStream struct {
 	Path        string
 	Keyframes   []float64
 	CanTransmux bool
+	Info        *MediaInfo
 	streams     map[Quality]TranscodeStream
 }
 
 func NewFileStream(path string) (*FileStream, error) {
+	info_chan := make(chan struct {
+		info *MediaInfo
+		err  error
+	})
+	go func() {
+		ret, err := GetInfo(path)
+		info_chan <- struct {
+			info *MediaInfo
+			err  error
+		}{ret, err}
+	}()
+
 	keyframes, can_transmux, err := GetKeyframes(path)
 	if err != nil {
 		return nil, err
 	}
+	info := <-info_chan
+	if info.err != nil {
+		return nil, err
+	}
 
 	return &FileStream{
 		Path:        path,
 		Keyframes:   keyframes,
 		CanTransmux: can_transmux,
+		Info:        info.info,
 		streams:     make(map[Quality]TranscodeStream),
 	}, nil
 }
@@ -102,5 +121,45 @@ func (fs *FileStream) Destroy() {
 }
 
 func (fs *FileStream) GetMaster() string {
-	return ""
+	master := "#EXTM3U\n"
+	// TODO: also check if the codec is valid in a hls before putting transmux
+	if fs.CanTransmux {
+		master += "#EXT-X-STREAM-INF:"
+		master += fmt.Sprintf("AVERAGE-BANDWIDTH=%d,", fs.Info.Video.Bitrate)
+		master += fmt.Sprintf("BANDWIDTH=%d,", int(float32(fs.Info.Video.Bitrate)*1.2))
+		master += fmt.Sprintf("RESOLUTION=%dx%d,", fs.Info.Video.Width, fs.Info.Video.Height)
+		master += "AUDIO=\"audio\","
+		master += "CLOSED-CAPTIONS=NONE\n"
+		master += fmt.Sprintf("./%s/index.m3u8\n", Original)
+	}
+	aspectRatio := float32(fs.Info.Video.Width) / float32(fs.Info.Video.Height)
+	for _, quality := range Qualities {
+		if quality.Height() < fs.Info.Video.Quality.Height() && quality.AverageBitrate() < fs.Info.Video.Bitrate {
+			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 += "CODECS=\"avc1.640028\","
+			master += "AUDIO=\"audio\","
+			master += "CLOSED-CAPTIONS=NONE\n"
+			master += fmt.Sprintf("./%s/index.m3u8\n", quality)
+		}
+	}
+	for _, audio := range fs.Info.Audios {
+		master += "#EXT-X-MEDIA:TYPE=AUDIO,"
+		master += "GROUP-ID=\"audio\","
+		if audio.Language != nil {
+			master += fmt.Sprintf("LANGUAGE=\"%s\",", *audio.Language)
+		}
+		if audio.Title != nil {
+			master += fmt.Sprintf("NAME=\"%s\",", *audio.Title)
+		} else if audio.Language != nil {
+			master += fmt.Sprintf("NAME=\"%s\",", *audio.Language)
+		} else {
+			master += fmt.Sprintf("NAME=\"Audio %d\",", audio.Index)
+		}
+		master += "DEFAULT=YES,"
+		master += fmt.Sprintf("URI=\"./audio/%d/index.m3u8\"\n", audio.Index)
+	}
+	return master
 }
diff --git a/transcoder/src/info.go b/transcoder/src/info.go
index ecc83f8e..1aabf8db 100644
--- a/transcoder/src/info.go
+++ b/transcoder/src/info.go
@@ -158,10 +158,10 @@ var SubtitleExtensions = map[string]string{
 	"vtt":    "vtt",
 }
 
-func GetInfo(path string) (MediaInfo, error) {
+func GetInfo(path string) (*MediaInfo, error) {
 	mi, err := mediainfo.Open(path)
 	if err != nil {
-		return MediaInfo{}, err
+		return nil, err
 	}
 	defer mi.Close()
 
@@ -181,7 +181,7 @@ func GetInfo(path string) (MediaInfo, error) {
 	chapters_begin := ParseUint(mi.Parameter(mediainfo.StreamMenu, 0, "Chapters_Pos_Begin"))
 	chapters_end := ParseUint(mi.Parameter(mediainfo.StreamMenu, 0, "Chapters_Pos_End"))
 
-	return MediaInfo{
+	return &MediaInfo{
 		Sha:  sha,
 		Path: path,
 		// Remove leading .
diff --git a/transcoder/src/quality.go b/transcoder/src/quality.go
index 702fe5ba..d9b634dd 100644
--- a/transcoder/src/quality.go
+++ b/transcoder/src/quality.go
@@ -14,6 +14,57 @@ const (
 	Original Quality = "original"
 )
 
+var Qualities = []Quality{P240, P360, P480, P720, P1080, P1440, P4k, P8k, Original}
+
+// I'm not entierly sure about the values for bitrates. Double checking would be nice.
+func (v Quality) AverageBitrate() uint32 {
+	switch v {
+	case P240:
+		return 400000
+	case P360:
+		return 800000
+	case P480:
+		return 1200000
+	case P720:
+		return 2400000
+	case P1080:
+		return 4800000
+	case P1440:
+		return 9600000
+	case P4k:
+		return 16000000
+	case P8k:
+		return 28000000
+	case Original:
+		panic("Original quality must be handled specially")
+	}
+	panic("Invalid quality value")
+}
+
+func (v Quality) MaxBitrate() uint32 {
+	switch v {
+	case P240:
+		return 700000
+	case P360:
+		return 1400000
+	case P480:
+		return 2100000
+	case P720:
+		return 4000000
+	case P1080:
+		return 8000000
+	case P1440:
+		return 12000000
+	case P4k:
+		return 28000000
+	case P8k:
+		return 40000000
+	case Original:
+		panic("Original quality must be handled specially")
+	}
+	panic("Invalid quality value")
+}
+
 func (q Quality) Height() uint32 {
 	switch q {
 	case P240:
@@ -39,7 +90,7 @@ func (q Quality) Height() uint32 {
 }
 
 func QualityFromHeight(height uint32) Quality {
-	qualities := []Quality{P240, P360, P480, P720, P1080, P1440, P4k, P8k, Original}
+	qualities := Qualities
 	for _, quality := range qualities {
 		if quality.Height() >= height {
 			return quality