Add 1.2 multiplier also for the source video bitrate

livepeer · Sep 12, 2023 · 13a6bf2 · 13a6bf2
1 parent 4a96b00
commit 13a6bf2
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Showing 2 changed files with 13 additions and 12 deletions.
diff --git a/video/profiles.go b/video/profiles.go
@@ -13,6 +13,9 @@ const (
 	TrackTypeVideo          = "video"
 	TrackTypeAudio          = "audio"
 	defaultQuality          = 27
+	// Livepeer network uses bitrate to set max bitrate for encoding, so for the video to look good, we multiply
+	// it by a factor of 1.2.
+	maxBitrateFactor = 1.2
 )
 
 type InputVideo struct {
@@ -143,9 +146,7 @@ func GetDefaultPlaybackProfiles(video InputTrack) ([]EncodedProfile, error) {
 		lowerQualityThanSrc := profile.Height < video.Height && profile.Bitrate < video.Bitrate
 		if lowerQualityThanSrc {
 			// relativeBitrate needs to be slightly higher than the proportional average bitrate of the source video.
-			// Livepeer network uses bitrate to set max bitrate for encoding, so for the video to look good, we multiply
-			// it by a factor of 1.2.
-			relativeBitrate := 1.2 * float64(profile.Width*profile.Height) * (float64(videoBitrate) / float64(video.Width*video.Height))
+			relativeBitrate := maxBitrateFactor * float64(profile.Width*profile.Height) * (float64(videoBitrate) / float64(video.Width*video.Height))
 			br := math.Min(relativeBitrate, float64(profile.Bitrate))
 			profile.Bitrate = int64(br)
 			profiles = append(profiles, profile)
@@ -156,7 +157,7 @@ func GetDefaultPlaybackProfiles(video InputTrack) ([]EncodedProfile, error) {
 	}
 	profiles = append(profiles, EncodedProfile{
 		Name:    strconv.FormatInt(nearestEven(video.Height), 10) + "p0",
-		Bitrate: videoBitrate,
+		Bitrate: int64(math.Min(maxBitrateFactor*float64(videoBitrate), MaxVideoBitrate)),
 		FPS:     0,
 		Width:   nearestEven(video.Width),
 		Height:  nearestEven(video.Height),

diff --git a/video/profiles_test.go b/video/profiles_test.go
@@ -27,7 +27,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "low-bitrate", Width: 640, Height: 360, Bitrate: 500_000, Quality: defaultQuality},
-				{Name: "360p0", Width: 640, Height: 360, Bitrate: 1_000_001, Quality: defaultQuality},
+				{Name: "360p0", Width: 640, Height: 360, Bitrate: 1_200_001, Quality: defaultQuality},
 			},
 		},
 		{
@@ -42,7 +42,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "low-bitrate", Width: 640, Height: 360, Bitrate: 250_000, Quality: defaultQuality},
-				{Name: "360p0", Width: 640, Height: 360, Bitrate: 500_000, Quality: defaultQuality},
+				{Name: "360p0", Width: 640, Height: 360, Bitrate: 600_000, Quality: defaultQuality},
 			},
 		},
 		{
@@ -57,7 +57,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "360p0", Width: 640, Height: 360, Bitrate: 1_000_000, Quality: defaultQuality},
-				{Name: "720p0", Width: 1280, Height: 720, Bitrate: 4_000_001, Quality: defaultQuality},
+				{Name: "720p0", Width: 1280, Height: 720, Bitrate: 4_800_001, Quality: defaultQuality},
 			},
 		},
 		{
@@ -72,7 +72,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "360p0", Width: 640, Height: 360, Bitrate: 320_000, Quality: defaultQuality},
-				{Name: "720p0", Width: 1200, Height: 720, Bitrate: 1_000_001, Quality: defaultQuality},
+				{Name: "720p0", Width: 1200, Height: 720, Bitrate: 1_200_001, Quality: defaultQuality},
 			},
 		},
 		{
@@ -88,7 +88,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			want: []EncodedProfile{
 				{Name: "360p0", Width: 640, Height: 360, Bitrate: 666_666, Quality: defaultQuality},
 				{Name: "720p0", Width: 1280, Height: 720, Bitrate: 2_666_666, Quality: defaultQuality},
-				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 5_000_000, Quality: defaultQuality},
+				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 6_000_000, Quality: defaultQuality},
 			},
 		},
 		{
@@ -103,7 +103,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "low-bitrate", Width: 400, Height: 240, Bitrate: 258549, Quality: defaultQuality},
-				{Name: "240p0", Width: 400, Height: 240, Bitrate: 517099, Quality: defaultQuality},
+				{Name: "240p0", Width: 400, Height: 240, Bitrate: 620518, Quality: defaultQuality},
 			},
 		},
 		{
@@ -134,7 +134,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "360p0", Width: 640, Height: 360, Bitrate: 146_666, Quality: defaultQuality},
-				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 1_100_000, Quality: defaultQuality},
+				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 1_320_000, Quality: defaultQuality},
 			},
 		},
 		{
@@ -149,7 +149,7 @@ func TestGetDefaultPlaybackProfiles(t *testing.T) {
 			},
 			want: []EncodedProfile{
 				{Name: "360p0", Width: 640, Height: 360, Bitrate: 146_666, Quality: defaultQuality},
-				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 1_100_000, Quality: defaultQuality},
+				{Name: "1080p0", Width: 1920, Height: 1080, Bitrate: 1_320_000, Quality: defaultQuality},
 			},
 		},
 	}