Add support to extract preview frames.

src/main/java/me/kavin/piped/utils/CollectionUtils.java

@@ -22,6 +22,11 @@ public class CollectionUtils {
         info.getStreamSegments().forEach(segment -> chapters.add(new ChapterSegment(segment.getTitle(), rewriteURL(segment.getPreviewUrl()),
                 segment.getStartTimeSeconds())));
 
+        final List<PreviewFrames> previewFrames = new ObjectArrayList<>();
+
+        info.getPreviewFrames().forEach(frame -> new PreviewFrames(frame.getUrls(), frame.getFrameWidth(), frame.getFrameHeight(),
+                frame.getTotalCount(), frame.getDurationPerFrame(), frame.getFramesPerPageX(), frame.getFramesPerPageY()));
+
         info.getSubtitles()
                 .forEach(subtitle -> subtitles.add(new Subtitle(rewriteURL(subtitle.getContent()),
                         subtitle.getFormat().getMimeType(), subtitle.getDisplayLanguageName(),
@@ -51,14 +56,12 @@ public class CollectionUtils {
 
         final List<ContentItem> relatedStreams = collectRelatedItems(info.getRelatedItems());
 
-        final Streams streams = new Streams(info.getName(), info.getDescription().getContent(),
+        return new Streams(info.getName(), info.getDescription().getContent(),
                 info.getTextualUploadDate(), info.getUploaderName(), substringYouTube(info.getUploaderUrl()),
                 rewriteURL(info.getUploaderAvatarUrl()), rewriteURL(info.getThumbnailUrl()), info.getDuration(),
                 info.getViewCount(), info.getLikeCount(), info.getDislikeCount(), info.getUploaderSubscriberCount(), info.isUploaderVerified(),
                 audioStreams, videoStreams, relatedStreams, subtitles, livestream, rewriteVideoURL(info.getHlsUrl()),
-                rewriteVideoURL(info.getDashMpdUrl()), null, chapters);
+                rewriteVideoURL(info.getDashMpdUrl()), null, chapters, previewFrames);
-
-        return streams;
     }
 
     public static List<ContentItem> collectRelatedItems(List<? extends InfoItem> items) {

src/main/java/me/kavin/piped/utils/obj/PreviewFrames.java

@@ -0,0 +1,20 @@
+package me.kavin.piped.utils.obj;
+
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+
+@AllArgsConstructor
+@NoArgsConstructor
+public class PreviewFrames {
+
+    public List<String> urls;
+    public int frameWidth;
+    public int frameHeight;
+    public int totalCount;
+    public int durationPerFrame;
+    public int framesPerPageX;
+    public int framesPerPageY;
+
+}

src/main/java/me/kavin/piped/utils/obj/Streams.java

@@ -27,11 +27,13 @@ public class Streams {
 
     public List<ChapterSegment> chapters;
 
+    public List<PreviewFrames> previewFrames;
+
     public Streams(String title, String description, String uploadDate, String uploader, String uploaderUrl,
                    String uploaderAvatar, String thumbnailUrl, long duration, long views, long likes, long dislikes, long uploaderSubscriberCount,
                    boolean uploaderVerified, List<PipedStream> audioStreams, List<PipedStream> videoStreams,
                    List<ContentItem> relatedStreams, List<Subtitle> subtitles, boolean livestream, String hls, String dash,
-                   String lbryId, List<ChapterSegment> chapters) {
+                   String lbryId, List<ChapterSegment> chapters, List<PreviewFrames> previewFrames) {
         this.title = title;
         this.description = description;
         this.uploadDate = uploadDate;
@@ -54,5 +56,6 @@ public class Streams {
         this.dash = dash;
         this.lbryId = lbryId;
         this.chapters = chapters;
+        this.previewFrames = previewFrames;
     }
 }