From 50fb5f927a4da433809bab1ad9bed8082f9c9a53 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Torbj=C3=B6rn=20Einarson?= <torbjorn@einarssons.se>
Date: Thu, 8 Aug 2024 16:13:11 +0200
Subject: [PATCH 1/2] feat: add stpp as possible mediaType in CreateEmptyTrak

---
 CHANGELOG.md       | 1 +
 mp4/initsegment.go | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cc16b6a..081f085 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Event Message boxes evte, emib, emeb
 - GetBtrt method to StsdBox
 - Btrt pointer attribute in AudioSampleEnntry
+- stpp can be used as value to CreateEmptyTrak
 
 ## [0.45.1] - 2024-07-12
 
diff --git a/mp4/initsegment.go b/mp4/initsegment.go
index 0d06bb1..0bf8987 100644
--- a/mp4/initsegment.go
+++ b/mp4/initsegment.go
@@ -156,7 +156,7 @@ func CreateEmptyTrak(trackID, timeScale uint32, mediaType, language string) *Tra
 		minf.AddChild(CreateVmhd())
 	case "audio":
 		minf.AddChild(CreateSmhd())
-	case "subtitle", "subtitles":
+	case "subtitle", "subtitles", "stpp":
 		minf.AddChild(&SthdBox{})
 	case "text", "wvtt":
 		minf.AddChild(&NmhdBox{})

From cf62a63ea78d297bf3e9a82c21d0a5577825264b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Torbj=C3=B6rn=20Einarson?= <torbjorn@einarssons.se>
Date: Thu, 8 Aug 2024 16:13:51 +0200
Subject: [PATCH 2/2] chore: fixing typos

---
 mp4/mediasegment.go | 2 +-
 mp4/trun.go         | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/mp4/mediasegment.go b/mp4/mediasegment.go
index e85a6f6..8231a35 100644
--- a/mp4/mediasegment.go
+++ b/mp4/mediasegment.go
@@ -10,7 +10,7 @@ import (
 // MediaSegment is an MP4 Media Segment with one or more Fragments.
 type MediaSegment struct {
 	Styp        *StypBox
-	Sidx        *SidxBox   // The fist sidx box in a segment
+	Sidx        *SidxBox   // The first sidx box in a segment
 	Sidxs       []*SidxBox // All sidx boxes in a segment
 	Fragments   []*Fragment
 	EncOptimize EncOptimize
diff --git a/mp4/trun.go b/mp4/trun.go
index 4955f9f..c3cf061 100644
--- a/mp4/trun.go
+++ b/mp4/trun.go
@@ -115,7 +115,8 @@ func DecodeTrunSR(hdr BoxHeader, startPos uint64, sr bits.SliceReader) (Box, err
 	return t, sr.AccError()
 }
 
-// CreateTrun - create a TrunBox for filling up with samples
+// CreateTrun - create a TrunBox for filling up with samples.
+// writeOrderNr is only used for multi-trun offsets.
 func CreateTrun(writeOrderNr uint32) *TrunBox {
 	trun := &TrunBox{
 		Version:          1,     // Signed composition_time_offset