[feature] Use gifv type for short soundless mp4 videos (#3182)

internal/gtsmodel/mediaattachment.go

@@ -91,6 +91,7 @@ const (
 	FileTypeImage   FileType = 1 // FileTypeImage is for jpegs, pngs, and standard gifs
 	FileTypeAudio   FileType = 2 // FileTypeAudio is for audio-only files (no video)
 	FileTypeVideo   FileType = 3 // FileTypeVideo is for files with audio + visual
+	FileTypeGifv    FileType = 4 // FileTypeGifv is for short video-only files (20s or less, mp4, no audio).
 )
 
 // String returns a stringified, frontend API compatible form of FileType.
@@ -104,6 +105,8 @@ func (t FileType) String() string {
 		return "audio"
 	case FileTypeVideo:
 		return "video"
+	case FileTypeGifv:
+		return "gifv"
 	default:
 		panic("invalid filetype")
 	}

internal/media/ffmpeg.go

@@ -305,7 +305,15 @@ func (res *result) GetFileType() (gtsmodel.FileType, string) {
 	case "mov,mp4,m4a,3gp,3g2,mj2":
 		switch {
 		case len(res.video) > 0:
-			return gtsmodel.FileTypeVideo, "mp4"
+			if len(res.audio) == 0 &&
+				res.duration <= 30 {
+				// Short, soundless
+				// video file aka gifv.
+				return gtsmodel.FileTypeGifv, "mp4"
+			} else {
+				// Video file (with or without audio).
+				return gtsmodel.FileTypeVideo, "mp4"
+			}
 		case len(res.audio) > 0 &&
 			res.audio[0].codec == "aac":
 			// m4a only supports [aac] audio.

internal/media/processingmedia.go

@@ -202,7 +202,8 @@ func (p *ProcessingMedia) store(ctx context.Context) error {
 
 	switch p.media.Type {
 	case gtsmodel.FileTypeImage,
-		gtsmodel.FileTypeVideo:
+		gtsmodel.FileTypeVideo,
+		gtsmodel.FileTypeGifv:
 		// Attempt to clean as metadata from file as possible.
 		if err := clearMetadata(ctx, temppath); err != nil {
 			return gtserror.Newf("error cleaning metadata: %w", err)