Videos: Transcode supported formats if bitrate exceeds limit #2461

Implements Option (1) as described in the issue comments.

internal/api/video.go

@@ -3,6 +3,7 @@ package api
 import (
 	"fmt"
 	"net/http"
+	"strings"
 
 	"github.com/photoprism/photoprism/pkg/video"
 
@@ -64,6 +65,14 @@ func GetVideo(router *gin.RouterGroup) {
 		}
 
 		fileName := photoprism.FileName(f.FileRoot, f.FileName)
+		fileBitrate := f.Bitrate()
+
+		// File format supported by the client/browser?
+		supported := f.FileCodec != "" && f.FileCodec == string(format.Codec) || format.Codec == video.UnknownCodec && f.FileType == string(format.File)
+
+		// File bitrate too high (for streaming)?
+		conf := service.Config()
+		transcode := !supported || conf.FFmpegEnabled() && conf.FFmpegBitrateExceeded(fileBitrate)
 
 		if mf, err := photoprism.NewMediaFile(fileName); err != nil {
 			// Set missing flag so that the file doesn't show up in search results anymore.
@@ -73,15 +82,13 @@ func GetVideo(router *gin.RouterGroup) {
 			log.Errorf("video: file %s is missing", clean.Log(f.FileName))
 			fileName = service.Config().StaticFile("video/404.mp4")
 			AddContentTypeHeader(c, ContentTypeAvc)
-		} else if f.FileCodec != "" && f.FileCodec == string(format.Codec) || format.Codec == video.UnknownCodec && f.FileType == string(format.File) {
-			if f.FileCodec != "" && f.FileCodec != f.FileType {
-				log.Debugf("video: %s has matching codec %s", clean.Log(f.FileName), clean.Log(f.FileCodec))
-				AddContentTypeHeader(c, fmt.Sprintf("%s; codecs=\"%s\"", f.FileMime, clean.Codec(f.FileCodec)))
+		} else if transcode {
+			if f.FileCodec != "" {
+				log.Debugf("video: %s is %s compressed and cannot be streamed directly, average bitrate %.1f MBit/s", clean.Log(f.FileName), clean.Log(strings.ToUpper(f.FileCodec)), fileBitrate)
 			} else {
-				log.Debugf("video: %s has matching type %s", clean.Log(f.FileName), clean.Log(f.FileType))
-				AddContentTypeHeader(c, f.FileMime)
+				log.Debugf("video: %s cannot be streamed directly, average bitrate %.1f MBit/s", clean.Log(f.FileName), fileBitrate)
 			}
-		} else {
+
 			conv := service.Convert()
 
 			if avcFile, err := conv.ToAvc(mf, service.Config().FFmpegEncoder(), false, false); err != nil {
@@ -93,6 +100,14 @@ func GetVideo(router *gin.RouterGroup) {
 			}
 
 			AddContentTypeHeader(c, ContentTypeAvc)
+		} else {
+			if f.FileCodec != "" && f.FileCodec != f.FileType {
+				log.Debugf("video: %s is %s compressed and requires no transcoding, average bitrate %.1f MBit/s", clean.Log(f.FileName), clean.Log(strings.ToUpper(f.FileCodec)), fileBitrate)
+				AddContentTypeHeader(c, fmt.Sprintf("%s; codecs=\"%s\"", f.FileMime, clean.Codec(f.FileCodec)))
+			} else {
+				log.Debugf("video: %s is streamed directly, average bitrate %.1f MBit/s", clean.Log(f.FileName), fileBitrate)
+				AddContentTypeHeader(c, f.FileMime)
+			}
 		}
 
 		if c.Query("download") != "" {

internal/config/config_ffmpeg.go

@@ -28,3 +28,14 @@ func (c *Config) FFmpegBitrate() int {
 		return c.options.FFmpegBitrate
 	}
 }
+
+// FFmpegBitrateExceeded tests if the ffmpeg bitrate limit is exceeded.
+func (c *Config) FFmpegBitrateExceeded(mbit float64) bool {
+	if mbit <= 0 {
+		return false
+	} else if max := c.FFmpegBitrate(); max <= 0 {
+		return false
+	} else {
+		return mbit > float64(max)
+	}
+}

internal/config/config_ffmpeg_test.go

@@ -42,3 +42,24 @@ func TestConfig_FFmpegBitrate(t *testing.T) {
 	c.options.FFmpegBitrate = 800
 	assert.Equal(t, 800, c.FFmpegBitrate())
 }
+
+func TestConfig_FFmpegBitrateExceeded(t *testing.T) {
+	c := NewConfig(CliTestContext())
+	c.options.FFmpegBitrate = 0
+	assert.False(t, c.FFmpegBitrateExceeded(0.95))
+	assert.False(t, c.FFmpegBitrateExceeded(1.05))
+	assert.False(t, c.FFmpegBitrateExceeded(2.05))
+	c.options.FFmpegBitrate = 1
+	assert.False(t, c.FFmpegBitrateExceeded(0.95))
+	assert.False(t, c.FFmpegBitrateExceeded(1.0))
+	assert.True(t, c.FFmpegBitrateExceeded(1.05))
+	assert.True(t, c.FFmpegBitrateExceeded(2.05))
+	c.options.FFmpegBitrate = 50
+	assert.False(t, c.FFmpegBitrateExceeded(0.95))
+	assert.False(t, c.FFmpegBitrateExceeded(1.05))
+	assert.False(t, c.FFmpegBitrateExceeded(2.05))
+	c.options.FFmpegBitrate = -5
+	assert.False(t, c.FFmpegBitrateExceeded(0.95))
+	assert.False(t, c.FFmpegBitrateExceeded(1.05))
+	assert.False(t, c.FFmpegBitrateExceeded(2.05))
+}

internal/entity/file.go

@@ -661,6 +661,17 @@ func (m *File) SetDuration(d time.Duration) {
 	}
 }
 
+// Bitrate returns the average bitrate in MBit/s if the file has a duration.
+func (m *File) Bitrate() float64 {
+	// Make sure size and duration have a positive value.
+	if m.FileSize <= 0 || m.FileDuration <= 0 {
+		return 0
+	}
+
+	// Divide number of bits through the duration in seconds.
+	return ((float64(m.FileSize) * 8) / m.FileDuration.Seconds()) / 1e6
+}
+
 // SetFPS sets the average number of frames per second.
 func (m *File) SetFPS(frameRate float64) {
 	if frameRate <= 0 {

internal/entity/file_test.go

@@ -780,3 +780,21 @@ func TestFile_SetDuration(t *testing.T) {
 		assert.Equal(t, 216000, m.FileFrames)
 	})
 }
+
+func TestFile_Bitrate(t *testing.T) {
+	t.Run("HasDuration", func(t *testing.T) {
+		m := File{FileDuration: 1e9 * 20.302, FileSize: 1826192}
+
+		assert.InEpsilon(t, 0.719, m.Bitrate(), 0.01)
+	})
+	t.Run("NoDuration", func(t *testing.T) {
+		m := File{FileDuration: 0, FileSize: 1826192}
+
+		assert.Equal(t, float64(0), m.Bitrate())
+	})
+	t.Run("NoSize", func(t *testing.T) {
+		m := File{FileDuration: 1e9 * 20.302, FileSize: 0}
+
+		assert.Equal(t, float64(0), m.Bitrate())
+	})
+}

internal/photoprism/convert_avc.go

@@ -139,9 +139,11 @@ func (c *Convert) AvcConvertCommand(f *MediaFile, avcName string, encoder ffmpeg
 	case bitrate == "":
 		return nil, false, fmt.Errorf("convert: transcoding bitrate is empty - possible bug")
 	case ffmpegBin == "":
-		return nil, false, fmt.Errorf("convert: ffmpeg must be installed to transcode %s to avc", clean.Log(f.BaseName()))
+		return nil, false, fmt.Errorf("convert: ffmpeg must be installed to transcode %s", clean.Log(f.BaseName()))
+	case c.conf.DisableFFmpeg():
+		return nil, false, fmt.Errorf("convert: ffmpeg must be enabled to transcode %s", clean.Log(f.BaseName()))
 	case !f.IsAnimated():
-		return nil, false, fmt.Errorf("convert: file type %s of %s cannot be transcoded to avc", f.FileType(), clean.Log(f.BaseName()))
+		return nil, false, fmt.Errorf("convert: file type %s of %s cannot be transcoded", f.FileType(), clean.Log(f.BaseName()))
 	}
 
 	return ffmpeg.AvcConvertCommand(fileName, avcName, ffmpegBin, c.AvcBitrate(f), encoder)