- Added support for auto-translated subtitles with auto_captions => 1.

When the config-option `auto_captions` is set to 1 and the auto-generated subtitle is not in a language that we want (specified in `srt_languages`), then we try to return a translated version of the auto-generated subtitle in a preferred language.

Author: trizen

lib/WWW/YoutubeViewer.pm

@@ -994,7 +994,16 @@ sub get_streaming_urls {
         my $caption_data  = $self->parse_json_string($captions_json);
 
         if (eval { ref($caption_data->{captions}{playerCaptionsTracklistRenderer}{captionTracks}) eq 'ARRAY' }) {
+
             push @caption_urls, @{$caption_data->{captions}{playerCaptionsTracklistRenderer}{captionTracks}};
+
+            my $translationLanguages = $caption_data->{captions}{playerCaptionsTracklistRenderer}{translationLanguages};
+
+            if (ref($translationLanguages) eq 'ARRAY') {
+                foreach my $caption (@caption_urls) {
+                    $caption->{translationLanguages} = $translationLanguages;
+                }
+            }
         }
     }
 

lib/WWW/YoutubeViewer/GetCaption.pm

@@ -122,6 +122,27 @@ sub find_caption_data {
         return $caption if defined($caption);
     }
 
+    # Return a translated subtitle (if available)
+    if ($self->{auto_captions}) {
+        foreach my $caption (@{$self->{captions}}) {
+
+            $caption->{isTranslatable}                       or next;
+            exists($caption->{translationLanguages})         or next;
+            ref($caption->{translationLanguages}) eq 'ARRAY' or next;
+
+            foreach my $lang (@{$self->{languages}}) {
+                foreach my $trans_lang (@{$caption->{translationLanguages}}) {
+                    if ($trans_lang->{languageCode} =~ /^\Q$lang\E(?:\z|[_-])/i) {
+                        my %caption_copy = %{$caption};
+                        $caption_copy{languageCode} = $trans_lang->{languageCode};
+                        $caption_copy{baseUrl} .= "&tlang=$trans_lang->{languageCode}";
+                        return \%caption_copy;
+                    }
+                }
+            }
+        }
+    }
+
     return;
 }