Merge pull request #199 from Dash-Industry-Forum/hevc-and-ac3

HEVC and AC-3 test asset and bug fix

CHANGELOG.md

@@ -7,10 +7,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Short HEVC + AC-3 test content
+
 ### Fixed
 
 - Will now set contentType from mimeType on AdaptationSet or Representation level.
 - If contentType and mimedType is not present, contentType will be set from codecs string.
+- Issue with audio resegmentation.
 
 ## [1.4.1] - 2024-05-28
 

cmd/livesim2/app/audiosegmentation.go

@@ -92,11 +92,14 @@ func createAudioSeg(vodFS fs.FS, a *asset, cfg *ResponseConfig, rec audioRecipe)
 			itvl := sampleItvl{i, startSampleIdx, 0, 0}
 			sampleItvls = append(sampleItvls, itvl)
 		}
-		if rec.audioInEnd > s.EndTime {
+		if rec.audioInEnd >= s.EndTime {
 			endSampleIdx = uint32((s.EndTime - s.StartTime) / sampleDur)
 			sampleItvls[len(sampleItvls)-1].endIdx = endSampleIdx
 			timeCollected += sampleItvls[len(sampleItvls)-1].dur(sampleDur)
 			nextAudioStart = s.EndTime
+			if nextAudioStart == rec.audioInEnd {
+				break
+			}
 			if i < lastIdx {
 				sampleItvls = append(sampleItvls, sampleItvl{i + 1, 0, 0, 0})
 				continue

cmd/livesim2/app/livesegment_test.go

@@ -108,6 +108,29 @@ func TestLiveSegment(t *testing.T) {
 	}
 }
 
+// TestAc3Timing checks that the generated segments end within one frame from nominal segment duration.
+func TestAc3Timing(t *testing.T) {
+	vodFS := os.DirFS("testdata/assets")
+	am := newAssetMgr(vodFS, "", false)
+	err := am.discoverAssets()
+	require.NoError(t, err)
+
+	asset, ok := am.findAsset("bbb_hevc_ac3_8s")
+	require.True(t, ok)
+	cfg := NewResponseConfig()
+	nowMS := 20_000
+	for sNr := 0; sNr <= 5; sNr++ {
+		media := "audio_$NrOrTime$.m4s"
+		media = strings.Replace(media, "$NrOrTime$", fmt.Sprintf("%d", sNr), -1)
+		so, err := genLiveSegment(vodFS, asset, cfg, media, nowMS)
+		require.NoError(t, err)
+		bmdt := int(so.seg.Fragments[0].Moof.Traf.Tfdt.BaseMediaDecodeTime())
+		overShoot := bmdt - (2 * sNr * 48000)
+		require.Less(t, overShoot, 1536)
+		require.GreaterOrEqual(t, overShoot, 0)
+	}
+}
+
 func TestCheckAudioSegmentTimeAddressing(t *testing.T) {
 	vodFS := os.DirFS("testdata/assets")
 	am := newAssetMgr(vodFS, "", false)

cmd/livesim2/app/testdata/assets/bbb_hevc_ac3_8s/manifest.mpd

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" minBufferTime="PT1.500S" type="static" mediaPresentationDuration="PT0H0M8.000S" maxSegmentDuration="PT0H0M2.016S" profiles="urn:mpeg:dash:profile:isoff-live:2011">
+ <ProgramInformation>
+  <Title>BigBuckBunny 8s generated with ffmpeg and MP4Box</Title>
+ </ProgramInformation>
+ <Period duration="PT0H0M8.000S">
+  <AdaptationSet segmentAlignment="true" contentType="video" maxWidth="640" maxHeight="360" maxFrameRate="24" par="16:9" lang="und" startWithSAP="1">
+   <SegmentTemplate media="video_$Number$.m4s" initialization="video_init.mp4" timescale="12288" startNumber="1" duration="24576"/>
+   <Representation id="1" mimeType="video/mp4" codecs="hev1.1.6.L63.90" width="640" height="360" frameRate="24" sar="1:1" bandwidth="741142">
+   </Representation>
+  </AdaptationSet>
+  <AdaptationSet segmentAlignment="true" contentType="audio" lang="und" startWithSAP="1">
+   <SegmentTemplate media="audio_$Number$.m4s" initialization="audio_init.mp4" timescale="48000" startNumber="1" duration="96000"/>
+   <Representation id="2" mimeType="audio/mp4" codecs="ac-3" audioSamplingRate="48000" bandwidth="96000">
+    <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
+   </Representation>
+  </AdaptationSet>
+ </Period>
+</MPD>