add caption

goutubedl.go

@@ -134,6 +134,7 @@ type Info struct {
 
 	Formats           []Format              `json:"formats"`
 	Subtitles         map[string][]Subtitle `json:"subtitles"`
+	AutomaticCaptions map[string][]*Caption `json:"automatic_captions"`
 
 	// Playlist entries if _type is playlist
 	Entries []Info `json:"entries"`
@@ -183,6 +184,13 @@ type Subtitle struct {
 	Bytes []byte `json:"-"`
 }
 
+type Caption struct {
+	Ext   string `json:"ext"`
+	URL   string `json:"url"`
+	Name  string `json:"name"`
+	Bytes []byte `json:"-"`
+}
+
 func (f Format) String() string {
 	return fmt.Sprintf("%s:%s:%s abr:%f vbr:%f tbr:%f",
 		f.FormatID,
@@ -223,6 +231,7 @@ type Options struct {
 	Downloader            string // --downloader
 	DownloadThumbnail     bool
 	DownloadSubtitles     bool
+	DownloadSubtitlesLang []string
 	DownloadSections      string // --download-sections
 	Impersonate           string // --impersonate
 
@@ -476,6 +485,22 @@ func infoFromURL(
 		}
 	}
 
+	for _, lang := range options.DownloadSubtitlesLang {
+		if _, ok := info.AutomaticCaptions[lang]; !ok {
+			continue
+		}
+
+		for _, caption := range info.AutomaticCaptions[lang] {
+			resp, respErr := get(caption.URL)
+			if respErr == nil {
+				buf, _ := io.ReadAll(resp.Body)
+				resp.Body.Close()
+				caption.Bytes = buf
+			}
+		}
+
+	}
+
 	if options.DownloadSubtitles {
 		for _, subtitles := range info.Subtitles {
 			for i, subtitle := range subtitles {