Added scene preview generator

api/resolver_query_metadata.go

@@ -21,7 +21,8 @@ func (r *queryResolver) MetadataExport(ctx context.Context) (string, error) {
 }
 
 func (r *queryResolver) MetadataGenerate(ctx context.Context) (string, error) {
-	panic("not implemented")
+	manager.GetInstance().Generate(true, true, true, true)
+	return "todo", nil
 }
 
 func (r *queryResolver) MetadataClean(ctx context.Context) (string, error) {

ffmpeg/encoder.go

@@ -1,7 +1,6 @@
 package ffmpeg
 
 import (
-	"fmt"
 	"github.com/stashapp/stash/logger"
 	"io/ioutil"
 	"os/exec"
@@ -11,65 +10,17 @@ import (
 
 var progressRegex = regexp.MustCompile(`time=(\d+):(\d+):(\d+.\d+)`)
 
-type encoder struct {
+type Encoder struct {
 	Path string
 }
 
-func NewEncoder(ffmpegPath string) encoder {
+func NewEncoder(ffmpegPath string) Encoder {
-	return encoder{
+	return Encoder{
 		Path: ffmpegPath,
 	}
 }
 
-type ScreenshotOptions struct {
+func (e *Encoder) run(probeResult VideoFile, args []string) (string, error) {
-	OutputPath string
-	Quality int
-	Time float64
-	Width int
-	Verbosity string
-}
-
-type TranscodeOptions struct {
-	OutputPath string
-}
-
-func (e *encoder) Screenshot(probeResult FFProbeResult, options ScreenshotOptions) {
-	if options.Verbosity == "" {
-		options.Verbosity = "quiet"
-	}
-	if options.Quality == 0 {
-		options.Quality = 1
-	}
-	args := []string{
-		"-v", options.Verbosity,
-		"-ss", fmt.Sprintf("%v", options.Time),
-		"-y",
-		"-i", probeResult.Path, // TODO: Wrap in quotes?
-		"-vframes", "1",
-		"-q:v", fmt.Sprintf("%v", options.Quality),
-		"-vf", fmt.Sprintf("scale=%v:-1", options.Width),
-		"-f", "image2",
-		options.OutputPath,
-	}
-	_, _ = e.run(probeResult, args)
-}
-
-func (e *encoder) Transcode(probeResult FFProbeResult, options TranscodeOptions) {
-	args := []string{
-		"-i", probeResult.Path,
-		"-c:v", "libx264",
-		"-profile:v", "high",
-		"-level", "4.2",
-		"-preset", "superfast",
-		"-crf", "23",
-		"-vf", "scale=iw:-2",
-		"-c:a", "aac",
-		options.OutputPath,
-	}
-	_, _ = e.run(probeResult, args)
-}
-
-func (e *encoder) run(probeResult FFProbeResult, args []string) (string, error) {
 	cmd := exec.Command(e.Path, args...)
 
 	stderr, err := cmd.StderrPipe()

ffmpeg/encoder_scene_preview_chunk.go

@@ -0,0 +1,65 @@
+package ffmpeg
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type ScenePreviewChunkOptions struct {
+	Time       int
+	Width      int
+	OutputPath string
+}
+
+func (e *Encoder) ScenePreviewVideoChunk(probeResult VideoFile, options ScenePreviewChunkOptions) {
+	args := []string{
+		"-v", "quiet",
+		"-ss", strconv.Itoa(options.Time),
+		"-t", "0.75",
+		"-i", probeResult.Path,
+		"-y",
+		"-c:v", "libx264",
+		"-profile:v", "high",
+		"-level", "4.2",
+		"-preset", "veryslow",
+		"-crf", "21",
+		"-threads", "4",
+		"-vf", fmt.Sprintf("scale=%v:-2", options.Width),
+		"-c:a", "aac",
+		"-b:a", "128k",
+		options.OutputPath,
+	}
+	_, _ = e.run(probeResult, args)
+}
+
+func (e *Encoder) ScenePreviewVideoChunkCombine(probeResult VideoFile, concatFilePath string, outputPath string) {
+	args := []string{
+		"-v", "quiet",
+		"-f", "concat",
+		"-i", concatFilePath,
+		"-y",
+		"-c", "copy",
+		outputPath,
+	}
+	_, _ = e.run(probeResult, args)
+}
+
+func (e *Encoder) ScenePreviewVideoToImage(probeResult VideoFile, width int, videoPreviewPath string, outputPath string) error {
+	args := []string{
+		"-v", "quiet",
+		"-i", videoPreviewPath,
+		"-y",
+		"-c:v", "libwebp",
+		"-lossless", "1",
+		"-q:v", "70",
+		"-compression_level", "6",
+		"-preset", "default",
+		"-loop", "0",
+		"-threads", "4",
+		"-vf", fmt.Sprintf("scale=%v:-2,fps=12", width),
+		"-an",
+		outputPath,
+	}
+	_, err := e.run(probeResult, args)
+	return err
+}

ffmpeg/encoder_screenshot.go

@@ -0,0 +1,32 @@
+package ffmpeg
+
+import "fmt"
+
+type ScreenshotOptions struct {
+	OutputPath string
+	Quality int
+	Time float64
+	Width int
+	Verbosity string
+}
+
+func (e *Encoder) Screenshot(probeResult VideoFile, options ScreenshotOptions) {
+	if options.Verbosity == "" {
+		options.Verbosity = "quiet"
+	}
+	if options.Quality == 0 {
+		options.Quality = 1
+	}
+	args := []string{
+		"-v", options.Verbosity,
+		"-ss", fmt.Sprintf("%v", options.Time),
+		"-y",
+		"-i", probeResult.Path, // TODO: Wrap in quotes?
+		"-vframes", "1",
+		"-q:v", fmt.Sprintf("%v", options.Quality),
+		"-vf", fmt.Sprintf("scale=%v:-1", options.Width),
+		"-f", "image2",
+		options.OutputPath,
+	}
+	_, _ = e.run(probeResult, args)
+}

ffmpeg/encoder_transcode.go

@@ -0,0 +1,20 @@
+package ffmpeg
+
+type TranscodeOptions struct {
+	OutputPath string
+}
+
+func (e *Encoder) Transcode(probeResult VideoFile, options TranscodeOptions) {
+	args := []string{
+		"-i", probeResult.Path,
+		"-c:v", "libx264",
+		"-profile:v", "high",
+		"-level", "4.2",
+		"-preset", "superfast",
+		"-crf", "23",
+		"-vf", "scale=iw:-2",
+		"-c:a", "aac",
+		options.OutputPath,
+	}
+	_, _ = e.run(probeResult, args)
+}

ffmpeg/ffprobe.go

@@ -6,18 +6,26 @@ import (
 	"math"
 	"os"
 	"os/exec"
-	"runtime"
 	"strconv"
 	"strings"
 	"time"
 )
 
-type ffprobeExecutable struct {
+var ValidCodecs = []string{"h264", "h265", "vp8", "vp9"}
-	Path string
+
+func IsValidCodec(codecName string) bool {
+	for _, c := range ValidCodecs {
+		if c == codecName {
+			return true
+		}
+	}
+	return false
 }
 
-type FFProbeResult struct {
+type VideoFile struct {
-	JSON ffprobeJSON
+	JSON FFProbeJSON
+	AudioStream *FFProbeStream
+	VideoStream *FFProbeStream
 
 	Path         string
 	Container    string
@@ -37,52 +45,62 @@ type FFProbeResult struct {
 	AudioCodec string
 }
 
-func NewFFProbe(ffprobePath string) ffprobeExecutable {
-	return ffprobeExecutable{
-		Path: ffprobePath,
-	}
-}
-
 // Execute exec command and bind result to struct.
-func (ffp *ffprobeExecutable) ProbeVideo(filePath string) (*FFProbeResult, error) {
+func NewVideoFile(ffprobePath string, videoPath string) (*VideoFile, error) {
-	args := []string{"-v", "quiet", "-print_format", "json", "-show_format", "-show_streams", "-show_error", filePath}
+	args := []string{"-v", "quiet", "-print_format", "json", "-show_format", "-show_streams", "-show_error", videoPath}
-	// Extremely slow on windows for some reason
+	//// Extremely slow on windows for some reason
-	if runtime.GOOS != "windows" {
+	//if runtime.GOOS != "windows" {
-		args = append(args, "-count_frames")
+	//	args = append(args, "-count_frames")
-	}
+	//}
-	out, err := exec.Command(ffp.Path, args...).Output()
+	out, err := exec.Command(ffprobePath, args...).Output()
 
 	if err != nil {
-		return nil, fmt.Errorf("FFProbe encountered an error with <%s>.\nError JSON:\n%s\nError: %s", filePath, string(out), err.Error())
+		return nil, fmt.Errorf("FFProbe encountered an error with <%s>.\nError JSON:\n%s\nError: %s", videoPath, string(out), err.Error())
 	}
 
-	probeJSON := &ffprobeJSON{}
+	probeJSON := &FFProbeJSON{}
 	if err := json.Unmarshal(out, probeJSON); err != nil {
 		return nil, err
 	}
 
-	result := ffp.newProbeResult(filePath, *probeJSON)
+	return parse(videoPath, probeJSON)
-	return result, nil
 }
 
-func (ffp *ffprobeExecutable) newProbeResult(filePath string, probeJson ffprobeJSON) *FFProbeResult {
+func parse(filePath string, probeJSON *FFProbeJSON) (*VideoFile, error) {
-	videoStreamIndex := ffp.getStreamIndex("video", probeJson)
+	if probeJSON == nil {
-	audioStreamIndex := ffp.getStreamIndex("audio", probeJson)
+		return nil, fmt.Errorf("failed to get ffprobe json")
+	}
+
+	result := &VideoFile{}
+	result.JSON = *probeJSON
+
+	if result.JSON.Error.Code != 0 {
+		return nil, fmt.Errorf("ffprobe error code %d: %s", result.JSON.Error.Code, result.JSON.Error.String)
+	}
+	//} else if (ffprobeResult.stderr.includes("could not find codec parameters")) {
+	//	throw new Error(`FFProbe [${filePath}] -> Could not find codec parameters`);
+	//} // TODO nil_or_unsupported.(video_stream) && nil_or_unsupported.(audio_stream)
 
-	result := &FFProbeResult{}
-	result.JSON = probeJson
 	result.Path = filePath
-	result.Container = probeJson.Format.FormatName
+
-	duration, _ := strconv.ParseFloat(probeJson.Format.Duration, 64)
+	result.Bitrate, _ = strconv.ParseInt(probeJSON.Format.BitRate, 10, 64)
+	result.Container = probeJSON.Format.FormatName
+	duration, _ := strconv.ParseFloat(probeJSON.Format.Duration, 64)
 	result.Duration = math.Round(duration*100)/100
-	result.StartTime, _ = strconv.ParseFloat(probeJson.Format.StartTime, 64)
-	result.Bitrate, _ = strconv.ParseInt(probeJson.Format.BitRate, 10, 64)
 	fileStat, _ := os.Stat(filePath)
 	result.Size = fileStat.Size()
-	result.CreationTime = probeJson.Format.Tags.CreationTime
+	result.StartTime, _ = strconv.ParseFloat(probeJSON.Format.StartTime, 64)
+	result.CreationTime = probeJSON.Format.Tags.CreationTime
 
-	if videoStreamIndex != -1 {
+	audioStream := result.GetAudioStream()
-		videoStream := probeJson.Streams[videoStreamIndex]
+	if audioStream != nil {
+		result.AudioCodec = audioStream.CodecName
+		result.AudioStream = audioStream
+	}
+
+	videoStream := result.GetVideoStream()
+	if videoStream != nil {
+		result.VideoStream = videoStream
 		result.VideoCodec = videoStream.CodecName
 		result.VideoBitrate, _ = strconv.ParseInt(videoStream.BitRate, 10, 64)
 		var framerate float64
@@ -104,14 +122,26 @@ func (ffp *ffprobeExecutable) newProbeResult(filePath string, probeJson ffprobeJ
 		}
 	}
 
-	if audioStreamIndex != -1 {
+	return result, nil
-		result.AudioCodec = probeJson.Streams[audioStreamIndex].CodecName
-	}
-
-	return result
 }
 
-func (ffp *ffprobeExecutable) getStreamIndex(fileType string, probeJson ffprobeJSON) int {
+func (v *VideoFile) GetAudioStream() *FFProbeStream {
+	index := v.getStreamIndex("audio", v.JSON)
+	if index != -1 {
+		return &v.JSON.Streams[index]
+	}
+	return nil
+}
+
+func (v *VideoFile) GetVideoStream() *FFProbeStream {
+	index := v.getStreamIndex("video", v.JSON)
+	if index != -1 {
+		return &v.JSON.Streams[index]
+	}
+	return nil
+}
+
+func (v *VideoFile) getStreamIndex(fileType string, probeJson FFProbeJSON) int {
 	for i, stream := range probeJson.Streams {
 		if stream.CodecType == fileType {
 			return i

ffmpeg/types.go

@@ -4,7 +4,7 @@ import (
 	"time"
 )
 
-type ffprobeJSON struct {
+type FFProbeJSON struct {
 	Format struct {
 		BitRate        string `json:"bit_rate"`
 		Duration       string `json:"duration"`
@@ -24,67 +24,69 @@ type ffprobeJSON struct {
 			MinorVersion     string    `json:"minor_version"`
 		} `json:"tags"`
 	} `json:"format"`
-	Streams []struct {
+	Streams []FFProbeStream `json:"streams"`
-		AvgFrameRate       string `json:"avg_frame_rate"`
-		BitRate            string `json:"bit_rate"`
-		BitsPerRawSample   string `json:"bits_per_raw_sample,omitempty"`
-		ChromaLocation     string `json:"chroma_location,omitempty"`
-		CodecLongName      string `json:"codec_long_name"`
-		CodecName          string `json:"codec_name"`
-		CodecTag           string `json:"codec_tag"`
-		CodecTagString     string `json:"codec_tag_string"`
-		CodecTimeBase      string `json:"codec_time_base"`
-		CodecType          string `json:"codec_type"`
-		CodedHeight        int    `json:"coded_height,omitempty"`
-		CodedWidth         int    `json:"coded_width,omitempty"`
-		DisplayAspectRatio string `json:"display_aspect_ratio,omitempty"`
-		Disposition        struct {
-			AttachedPic     int `json:"attached_pic"`
-			CleanEffects    int `json:"clean_effects"`
-			Comment         int `json:"comment"`
-			Default         int `json:"default"`
-			Dub             int `json:"dub"`
-			Forced          int `json:"forced"`
-			HearingImpaired int `json:"hearing_impaired"`
-			Karaoke         int `json:"karaoke"`
-			Lyrics          int `json:"lyrics"`
-			Original        int `json:"original"`
-			TimedThumbnails int `json:"timed_thumbnails"`
-			VisualImpaired  int `json:"visual_impaired"`
-		} `json:"disposition"`
-		Duration          string  `json:"duration"`
-		DurationTs        int     `json:"duration_ts"`
-		HasBFrames        int     `json:"has_b_frames,omitempty"`
-		Height            int     `json:"height,omitempty"`
-		Index             int     `json:"index"`
-		IsAvc             string  `json:"is_avc,omitempty"`
-		Level             int     `json:"level,omitempty"`
-		NalLengthSize     string  `json:"nal_length_size,omitempty"`
-		NbFrames          string  `json:"nb_frames"`
-		PixFmt            string  `json:"pix_fmt,omitempty"`
-		Profile           string  `json:"profile"`
-		RFrameRate        string  `json:"r_frame_rate"`
-		Refs              int     `json:"refs,omitempty"`
-		SampleAspectRatio string  `json:"sample_aspect_ratio,omitempty"`
-		StartPts          int     `json:"start_pts"`
-		StartTime         string  `json:"start_time"`
-		Tags              struct {
-			CreationTime time.Time `json:"creation_time"`
-			HandlerName  string    `json:"handler_name"`
-			Language     string    `json:"language"`
-			Rotate		 string    `json:"rotate"`
-		} `json:"tags"`
-		TimeBase      string `json:"time_base"`
-		Width         int    `json:"width,omitempty"`
-		BitsPerSample int    `json:"bits_per_sample,omitempty"`
-		ChannelLayout string `json:"channel_layout,omitempty"`
-		Channels      int    `json:"channels,omitempty"`
-		MaxBitRate    string `json:"max_bit_rate,omitempty"`
-		SampleFmt     string `json:"sample_fmt,omitempty"`
-		SampleRate    string `json:"sample_rate,omitempty"`
-	} `json:"streams"`
 	Error struct {
 		Code   int    `json:"code"`
 		String string `json:"string"`
 	} `json:"error"`
+}
+
+type FFProbeStream struct {
+	AvgFrameRate       string `json:"avg_frame_rate"`
+	BitRate            string `json:"bit_rate"`
+	BitsPerRawSample   string `json:"bits_per_raw_sample,omitempty"`
+	ChromaLocation     string `json:"chroma_location,omitempty"`
+	CodecLongName      string `json:"codec_long_name"`
+	CodecName          string `json:"codec_name"`
+	CodecTag           string `json:"codec_tag"`
+	CodecTagString     string `json:"codec_tag_string"`
+	CodecTimeBase      string `json:"codec_time_base"`
+	CodecType          string `json:"codec_type"`
+	CodedHeight        int    `json:"coded_height,omitempty"`
+	CodedWidth         int    `json:"coded_width,omitempty"`
+	DisplayAspectRatio string `json:"display_aspect_ratio,omitempty"`
+	Disposition        struct {
+		AttachedPic     int `json:"attached_pic"`
+		CleanEffects    int `json:"clean_effects"`
+		Comment         int `json:"comment"`
+		Default         int `json:"default"`
+		Dub             int `json:"dub"`
+		Forced          int `json:"forced"`
+		HearingImpaired int `json:"hearing_impaired"`
+		Karaoke         int `json:"karaoke"`
+		Lyrics          int `json:"lyrics"`
+		Original        int `json:"original"`
+		TimedThumbnails int `json:"timed_thumbnails"`
+		VisualImpaired  int `json:"visual_impaired"`
+	} `json:"disposition"`
+	Duration          string  `json:"duration"`
+	DurationTs        int     `json:"duration_ts"`
+	HasBFrames        int     `json:"has_b_frames,omitempty"`
+	Height            int     `json:"height,omitempty"`
+	Index             int     `json:"index"`
+	IsAvc             string  `json:"is_avc,omitempty"`
+	Level             int     `json:"level,omitempty"`
+	NalLengthSize     string  `json:"nal_length_size,omitempty"`
+	NbFrames          string  `json:"nb_frames"`
+	PixFmt            string  `json:"pix_fmt,omitempty"`
+	Profile           string  `json:"profile"`
+	RFrameRate        string  `json:"r_frame_rate"`
+	Refs              int     `json:"refs,omitempty"`
+	SampleAspectRatio string  `json:"sample_aspect_ratio,omitempty"`
+	StartPts          int     `json:"start_pts"`
+	StartTime         string  `json:"start_time"`
+	Tags              struct {
+		CreationTime time.Time `json:"creation_time"`
+		HandlerName  string    `json:"handler_name"`
+		Language     string    `json:"language"`
+		Rotate		 string    `json:"rotate"`
+	} `json:"tags"`
+	TimeBase      string `json:"time_base"`
+	Width         int    `json:"width,omitempty"`
+	BitsPerSample int    `json:"bits_per_sample,omitempty"`
+	ChannelLayout string `json:"channel_layout,omitempty"`
+	Channels      int    `json:"channels,omitempty"`
+	MaxBitRate    string `json:"max_bit_rate,omitempty"`
+	SampleFmt     string `json:"sample_fmt,omitempty"`
+	SampleRate    string `json:"sample_rate,omitempty"`
 }

manager/generator.go

@@ -0,0 +1,62 @@
+package manager
+
+import (
+	"fmt"
+	"github.com/stashapp/stash/ffmpeg"
+	"github.com/stashapp/stash/logger"
+	"github.com/stashapp/stash/utils"
+	"os/exec"
+	"strconv"
+)
+
+type Generator struct {
+	ChunkCount     int
+	FrameRate      float64
+	NumberOfFrames int
+	NthFrame       int
+
+	VideoFile ffmpeg.VideoFile
+}
+
+func newGenerator(videoFile ffmpeg.VideoFile) (*Generator, error) {
+	exists, err := utils.FileExists(videoFile.Path)
+	if !exists {
+		logger.Errorf("video file not found")
+		return nil, err
+	}
+
+	generator := &Generator{VideoFile: videoFile}
+	return generator, nil
+}
+
+func (g *Generator) configure() error {
+	videoStream := g.VideoFile.VideoStream
+	if videoStream == nil {
+		return fmt.Errorf("missing video stream")
+	}
+
+	var framerate float64
+	if g.VideoFile.FrameRate == 0 {
+		framerate, _ = strconv.ParseFloat(videoStream.RFrameRate, 64)
+	} else {
+		framerate = g.VideoFile.FrameRate
+	}
+	g.FrameRate = framerate
+
+	numberOfFrames, _ := strconv.Atoi(videoStream.NbFrames)
+	if numberOfFrames == 0 {
+		command := `ffmpeg -nostats -i `+g.VideoFile.Path+` -vcodec copy -f rawvideo -y /dev/null 2>&1 | \
+                       grep frame | \
+                       awk '{split($0,a,"fps")}END{print a[1]}' | \
+                       sed 's/.*= *//'`
+		commandResult, _ := exec.Command(command).Output()
+		numberOfFrames, _ := strconv.Atoi(string(commandResult))
+		if numberOfFrames == 0 { // TODO: test
+			numberOfFrames = int(framerate * g.VideoFile.Duration)
+		}
+	}
+	g.NumberOfFrames = numberOfFrames
+	g.NthFrame = g.NumberOfFrames / g.ChunkCount
+
+	return nil
+}

manager/generator_preview.go

@@ -0,0 +1,127 @@
+package manager
+
+import (
+	"bufio"
+	"fmt"
+	"github.com/stashapp/stash/ffmpeg"
+	"github.com/stashapp/stash/logger"
+	"github.com/stashapp/stash/utils"
+	"os"
+	"path"
+)
+
+type PreviewGenerator struct {
+	generator *Generator
+
+	VideoFilename string
+	ImageFilename string
+	OutputDirectory string
+}
+
+func NewPreviewGenerator(videoFile ffmpeg.VideoFile, videoFilename string, imageFilename string, outputDirectory string) (*PreviewGenerator, error) {
+	exists, err := utils.FileExists(videoFile.Path)
+	if !exists {
+		return nil, err
+	}
+	generator, err := newGenerator(videoFile)
+	if err != nil {
+		return nil, err
+	}
+	generator.ChunkCount = 12 // 12 segments to the preview
+	if err := generator.configure(); err != nil {
+		return nil, err
+	}
+
+	return &PreviewGenerator{
+		generator: generator,
+		VideoFilename: videoFilename,
+		ImageFilename: imageFilename,
+		OutputDirectory: outputDirectory,
+	}, nil
+}
+
+func (g *PreviewGenerator) Generate() error {
+	instance.Paths.Generated.EmptyTmpDir()
+	logger.Infof("[generator] generating scene preview for %s", g.generator.VideoFile.Path)
+	encoder := ffmpeg.NewEncoder(instance.Paths.FixedPaths.FFMPEG)
+
+	if err := g.generateConcatFile(); err != nil {
+		return err
+	}
+	if err := g.generateVideo(&encoder); err != nil {
+		return err
+	}
+	if err := g.generateImage(&encoder); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (g *PreviewGenerator) generateConcatFile() error {
+	f, err := os.Create(g.getConcatFilePath())
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	w := bufio.NewWriter(f)
+	for i := 0; i < g.generator.ChunkCount; i++ {
+		num := fmt.Sprintf("%.3d", i)
+		filename := "preview"+num+".mp4"
+		_, _ = w.WriteString(fmt.Sprintf("file '%s'\n", filename))
+	}
+	return w.Flush()
+}
+
+func (g *PreviewGenerator) generateVideo(encoder *ffmpeg.Encoder) error {
+	outputPath := path.Join(g.OutputDirectory, g.VideoFilename)
+	outputExists, _ := utils.FileExists(outputPath)
+	if outputExists {
+		return nil
+	}
+
+	stepSize := int(g.generator.VideoFile.Duration / float64(g.generator.ChunkCount))
+	for i := 0; i < g.generator.ChunkCount; i++ {
+		time := i * stepSize
+		num := fmt.Sprintf("%.3d", i)
+		filename := "preview"+num+".mp4"
+		chunkOutputPath := instance.Paths.Generated.GetTmpPath(filename)
+
+		options := ffmpeg.ScenePreviewChunkOptions{
+			Time: time,
+			Width: 640,
+			OutputPath: chunkOutputPath,
+		}
+		encoder.ScenePreviewVideoChunk(g.generator.VideoFile, options)
+	}
+
+	videoOutputPath := path.Join(g.OutputDirectory, g.VideoFilename)
+	encoder.ScenePreviewVideoChunkCombine(g.generator.VideoFile, g.getConcatFilePath(), videoOutputPath)
+	logger.Debug("created video preview: ", videoOutputPath)
+	return nil
+}
+
+func (g *PreviewGenerator) generateImage(encoder *ffmpeg.Encoder) error {
+	outputPath := path.Join(g.OutputDirectory, g.ImageFilename)
+	outputExists, _ := utils.FileExists(outputPath)
+	if outputExists {
+		return nil
+	}
+
+	videoPreviewPath := path.Join(g.OutputDirectory, g.VideoFilename)
+	tmpOutputPath := instance.Paths.Generated.GetTmpPath(g.ImageFilename)
+	if err := encoder.ScenePreviewVideoToImage(g.generator.VideoFile, 640, videoPreviewPath, tmpOutputPath); err != nil {
+		return err
+	} else {
+		if err := os.Rename(tmpOutputPath, outputPath); err != nil {
+			return err
+		}
+		logger.Debug("created video preview image: ", outputPath)
+	}
+
+	return nil
+}
+
+func (g *PreviewGenerator) getConcatFilePath() string {
+	return instance.Paths.Generated.GetTmpPath("files.txt")
+}

manager/manager.go

@@ -4,6 +4,7 @@ import (
 	"github.com/bmatcuk/doublestar"
 	"github.com/stashapp/stash/logger"
 	"github.com/stashapp/stash/manager/paths"
+	"github.com/stashapp/stash/models"
 	"path/filepath"
 	"sync"
 )
@@ -85,10 +86,70 @@ func (s *singleton) Export() {
 	}()
 }
 
+func (s *singleton) Generate(sprites bool, previews bool, markers bool, transcodes bool) {
+	if s.Status != Idle { return }
+	s.Status = Generate
+
+	qb := models.NewSceneQueryBuilder()
+	//this.job.total = await ObjectionUtils.getCount(Scene);
+	instance.Paths.Generated.EnsureTmpDir()
+
+	go func() {
+		defer s.returnToIdleState()
+
+		scenes, err := qb.All()
+		if err != nil {
+			logger.Errorf("failed to get scenes for generate")
+			return
+		}
+
+		delta := btoi(sprites) + btoi(previews) + btoi(markers) + btoi(transcodes)
+		var wg sync.WaitGroup
+		for _, scene := range scenes {
+			wg.Add(delta)
+
+			if sprites {
+				go func() {
+					wg.Done() // TODO
+				}()
+			}
+
+			if previews {
+				task := GeneratePreviewTask{Scene: scene}
+				go task.Start(&wg)
+			}
+
+			if markers {
+				go func() {
+					wg.Done() // TODO
+				}()
+			}
+
+			if transcodes {
+				go func() {
+					wg.Done() // TODO
+				}()
+			}
+
+			wg.Wait()
+		}
+	}()
+}
+
 func (s *singleton) returnToIdleState() {
 	if r := recover(); r!= nil {
 		logger.Info("recovered from ", r)
 	}
 
+	if s.Status == Generate {
+		instance.Paths.Generated.RemoveTmpDir()
+	}
 	s.Status = Idle
 }
+
+func btoi(b bool) int {
+	if b {
+		return 1
+	}
+	return 0
+}

manager/task_generate_preview.go

@@ -0,0 +1,58 @@
+package manager
+
+import (
+	"github.com/stashapp/stash/ffmpeg"
+	"github.com/stashapp/stash/logger"
+	"github.com/stashapp/stash/models"
+	"github.com/stashapp/stash/utils"
+	"sync"
+)
+
+type GeneratePreviewTask struct {
+	Scene models.Scene
+}
+
+func (t *GeneratePreviewTask) Start(wg *sync.WaitGroup) {
+	videoFilename := t.videoFilename()
+	imageFilename := t.imageFilename()
+	if t.doesPreviewExist(videoFilename, imageFilename) {
+		wg.Done()
+		return
+	}
+
+	videoFile, err := ffmpeg.NewVideoFile(instance.Paths.FixedPaths.FFProbe, t.Scene.Path)
+	if err != nil {
+		logger.Errorf("error reading video file: %s", err.Error())
+		wg.Done()
+		return
+	}
+
+	generator, err := NewPreviewGenerator(*videoFile, videoFilename, imageFilename, instance.Paths.Generated.Screenshots)
+	if err != nil {
+		logger.Errorf("error creating preview generator: %s", err.Error())
+		wg.Done()
+		return
+	}
+
+	if err := generator.Generate(); err != nil {
+		logger.Errorf("error generating preview: %s", err.Error())
+		wg.Done()
+		return
+	}
+
+	wg.Done()
+}
+
+func (t *GeneratePreviewTask) doesPreviewExist(videoFilename string, imageFilename string) bool {
+	videoExists, _ := utils.FileExists(instance.Paths.Scene.GetStreamPreviewPath(videoFilename))
+	imageExists, _ := utils.FileExists(instance.Paths.Scene.GetStreamPreviewImagePath(imageFilename))
+	return videoExists && imageExists
+}
+
+func (t *GeneratePreviewTask) videoFilename() string {
+	return t.Scene.Checksum + ".mp4"
+}
+
+func (t *GeneratePreviewTask) imageFilename() string {
+	return t.Scene.Checksum + ".webp"
+}

manager/task_scan.go

@@ -70,8 +70,7 @@ func (t *ScanTask) scanGallery() {
 }
 
 func (t *ScanTask) scanScene() {
-	ffprobe := ffmpeg.NewFFProbe(instance.Paths.FixedPaths.FFProbe)
+	videoFile, err := ffmpeg.NewVideoFile(instance.Paths.FixedPaths.FFProbe, t.FilePath)
-	ffprobeResult, err := ffprobe.ProbeVideo(t.FilePath)
 	if err != nil {
 		logger.Error(err.Error())
 		return
@@ -90,7 +89,7 @@ func (t *ScanTask) scanScene() {
 		return
 	}
 
-	t.makeScreenshots(*ffprobeResult, checksum)
+	t.makeScreenshots(*videoFile, checksum)
 
 	scene, _ = qb.FindByChecksum(checksum)
 	ctx := context.TODO()
@@ -105,14 +104,14 @@ func (t *ScanTask) scanScene() {
 		newScene := models.Scene{
 			Checksum: checksum,
 			Path: t.FilePath,
-			Duration: sql.NullFloat64{Float64: ffprobeResult.Duration, Valid: true },
+			Duration: sql.NullFloat64{Float64: videoFile.Duration, Valid: true },
-			VideoCodec: sql.NullString{ String: ffprobeResult.VideoCodec, Valid: true},
+			VideoCodec: sql.NullString{ String: videoFile.VideoCodec, Valid: true},
-			AudioCodec: sql.NullString{ String: ffprobeResult.AudioCodec, Valid: true},
+			AudioCodec: sql.NullString{ String: videoFile.AudioCodec, Valid: true},
-			Width: sql.NullInt64{ Int64: int64(ffprobeResult.Width), Valid: true },
+			Width: sql.NullInt64{ Int64: int64(videoFile.Width), Valid: true },
-			Height: sql.NullInt64{ Int64: int64(ffprobeResult.Height), Valid: true },
+			Height: sql.NullInt64{ Int64: int64(videoFile.Height), Valid: true },
-			Framerate: sql.NullFloat64{ Float64: ffprobeResult.FrameRate, Valid: true },
+			Framerate: sql.NullFloat64{ Float64: videoFile.FrameRate, Valid: true },
-			Bitrate: sql.NullInt64{ Int64: ffprobeResult.Bitrate, Valid: true },
+			Bitrate: sql.NullInt64{ Int64: videoFile.Bitrate, Valid: true },
-			Size: sql.NullString{ String: strconv.Itoa(int(ffprobeResult.Size)), Valid: true },
+			Size: sql.NullString{ String: strconv.Itoa(int(videoFile.Size)), Valid: true },
 			CreatedAt: models.SQLiteTimestamp{ Timestamp: currentTime },
 			UpdatedAt: models.SQLiteTimestamp{ Timestamp: currentTime },
 		}
@@ -127,7 +126,7 @@ func (t *ScanTask) scanScene() {
 	}
 }
 
-func (t *ScanTask) makeScreenshots(probeResult ffmpeg.FFProbeResult, checksum string) {
+func (t *ScanTask) makeScreenshots(probeResult ffmpeg.VideoFile, checksum string) {
 	thumbPath := instance.Paths.Scene.GetThumbnailScreenshotPath(checksum)
 	normalPath := instance.Paths.Scene.GetScreenshotPath(checksum)
 
@@ -142,7 +141,7 @@ func (t *ScanTask) makeScreenshots(probeResult ffmpeg.FFProbeResult, checksum st
 	t.makeScreenshot(probeResult, normalPath, 2, probeResult.Width)
 }
 
-func (t *ScanTask) makeScreenshot(probeResult ffmpeg.FFProbeResult, outputPath string, quality int, width int) {
+func (t *ScanTask) makeScreenshot(probeResult ffmpeg.VideoFile, outputPath string, quality int, width int) {
 	encoder := ffmpeg.NewEncoder(instance.Paths.FixedPaths.FFMPEG)
 	options := ffmpeg.ScreenshotOptions{
 		OutputPath: outputPath,