Restructure ffmpeg (#2392)

* Refactor transcode generation
* Move phash generation into separate package
* Refactor image thumbnail generation
* Move JSONTime to separate package
* Ffmpeg refactoring
* Refactor live transcoding
* Refactor scene marker preview generation
* Refactor preview generation
* Refactor screenshot generation
* Refactor sprite generation
* Change ffmpeg.IsStreamable to return error
* Move frame rate calculation into ffmpeg
* Refactor file locking
* Refactor title set during scan
* Add missing lockmanager instance
* Return error instead of logging in MatchContainer

pkg/scene/generate/screenshot.go

@@ -0,0 +1,101 @@
+package generate
+
+import (
+	"context"
+
+	"github.com/stashapp/stash/pkg/ffmpeg/transcoder"
+	"github.com/stashapp/stash/pkg/fsutil"
+	"github.com/stashapp/stash/pkg/logger"
+)
+
+const (
+	thumbnailWidth   = 320
+	thumbnailQuality = 5
+
+	screenshotQuality = 2
+
+	screenshotDurationProportion = 0.2
+)
+
+type ScreenshotOptions struct {
+	At *float64
+}
+
+func (g Generator) Screenshot(ctx context.Context, input string, hash string, videoWidth int, videoDuration float64, options ScreenshotOptions) error {
+	lockCtx := g.LockManager.ReadLock(ctx, input)
+	defer lockCtx.Cancel()
+
+	output := g.ScenePaths.GetScreenshotPath(hash)
+	if !g.Overwrite {
+		if exists, _ := fsutil.FileExists(output); exists {
+			return nil
+		}
+	}
+
+	at := screenshotDurationProportion * videoDuration
+	if options.At != nil {
+		at = *options.At
+	}
+
+	if err := g.generateFile(lockCtx, g.ScenePaths, jpgPattern, output, g.screenshot(input, screenshotOptions{
+		Time:    at,
+		Quality: screenshotQuality,
+		// default Width is video width
+	})); err != nil {
+		return err
+	}
+
+	logger.Debug("created screenshot: ", output)
+
+	return nil
+}
+
+func (g Generator) Thumbnail(ctx context.Context, input string, hash string, videoDuration float64, options ScreenshotOptions) error {
+	lockCtx := g.LockManager.ReadLock(ctx, input)
+	defer lockCtx.Cancel()
+
+	output := g.ScenePaths.GetThumbnailScreenshotPath(hash)
+	if !g.Overwrite {
+		if exists, _ := fsutil.FileExists(output); exists {
+			return nil
+		}
+	}
+
+	at := screenshotDurationProportion * videoDuration
+	if options.At != nil {
+		at = *options.At
+	}
+
+	if err := g.generateFile(lockCtx, g.ScenePaths, jpgPattern, output, g.screenshot(input, screenshotOptions{
+		Time:    at,
+		Quality: thumbnailQuality,
+		Width:   thumbnailWidth,
+	})); err != nil {
+		return err
+	}
+
+	logger.Debug("created thumbnail: ", output)
+
+	return nil
+}
+
+type screenshotOptions struct {
+	Time    float64
+	Width   int
+	Quality int
+}
+
+func (g Generator) screenshot(input string, options screenshotOptions) generateFn {
+	return func(lockCtx *fsutil.LockContext, tmpFn string) error {
+		ssOptions := transcoder.ScreenshotOptions{
+			OutputPath: tmpFn,
+			OutputType: transcoder.ScreenshotOutputTypeImage2,
+			Quality:    options.Quality,
+			Width:      options.Width,
+		}
+
+		args := transcoder.ScreenshotTime(input, options.Time, ssOptions)
+
+		return g.generate(lockCtx, args)
+	}
+}