API: Return actual stream height, width and fps (#4586)

At the moment Invidious will return hardcoded data for the 'size',
'qualityLabel' and 'fps' fields for streams, when such hardcoded data is
available, otherwise it just omits those fields from the response (e.g. with
the AV1 formats). Those issues are especially noticable when Invidious claims
that 50fps streams have 60fps and when it claims that the dimensions for a
vertical video are landscape. The DASH manifests that Invidious generates
already use the correct information.

This pull request corrects that issue by returning the information that
YouTube provides instead of hardcoded values and also fixes the long
standing bug of Invidious claiming that audio streams have 30 fps.

Here are two test cases:
50/25/13fps: https://youtu.be/GbXYZwUigCM (/api/v1/videos/GbXYZwUigCM)
vertical video: https://youtu.be/hxQwWEOOyU8 (/api/v1/videos/hxQwWEOOyU8)

Originally these problems were going to be solved by the complete refactor
of stream handling in 3620, but as that pull request got closed by the stale
bot over a month ago and has such a massive scope that it would require a
massive amount of work to complete it, I decided to open this pull request
that takes a less radical approach of just fixing bugs instead of a full
on refactoring.

FreeTube generates it's own DASH manifests instead of using Invidious' one,
so that it can support multiple audio tracks and HDR. Unfortunately due to
the missing and inaccurate information in the API responses, FreeTube has
to request the DASH manifest from Invidious to extract the height, width and
fps. With this pull request FreeTube could rely just on the API response,
saving that extra request to the Invidious instance. It would also make it
possible for FreeTube to use the vp9 streams with Invidious, which would
reduce the load on the video proxies.

Closes issue 4131

src/invidious/jsonify/api_v1/video_json.cr

@@ -114,25 +114,31 @@ module Invidious::JSONify::APIv1
 
               json.field "projectionType", fmt["projectionType"]
 
-              if fmt_info = Invidious::Videos::Formats.itag_to_metadata?(fmt["itag"])
+              height = fmt["height"]?.try &.as_i
-                fps = fmt_info["fps"]?.try &.to_i || fmt["fps"]?.try &.as_i || 30
+              width = fmt["width"]?.try &.as_i
+
+              fps = fmt["fps"]?.try &.as_i
+
+              if fps
                 json.field "fps", fps
+              end
+
+              if height && width
+                json.field "size", "#{width}x#{height}"
+                json.field "resolution", "#{height}p"
+
+                quality_label = "#{width > height ? height : width}p"
+
+                if fps && fps > 30
+                  quality_label += fps.to_s
+                end
+
+                json.field "qualityLabel", quality_label
+              end
+
+              if fmt_info = Invidious::Videos::Formats.itag_to_metadata?(fmt["itag"])
                 json.field "container", fmt_info["ext"]
                 json.field "encoding", fmt_info["vcodec"]? || fmt_info["acodec"]
-
-                if fmt_info["height"]?
-                  json.field "resolution", "#{fmt_info["height"]}p"
-
-                  quality_label = "#{fmt_info["height"]}p"
-                  if fps > 30
-                    quality_label += "60"
-                  end
-                  json.field "qualityLabel", quality_label
-
-                  if fmt_info["width"]?
-                    json.field "size", "#{fmt_info["width"]}x#{fmt_info["height"]}"
-                  end
-                end
               end
 
               # Livestream chunk infos
@@ -163,26 +169,31 @@ module Invidious::JSONify::APIv1
 
               json.field "bitrate", fmt["bitrate"].as_i.to_s if fmt["bitrate"]?
 
-              fmt_info = Invidious::Videos::Formats.itag_to_metadata?(fmt["itag"])
+              height = fmt["height"]?.try &.as_i
-              if fmt_info
+              width = fmt["width"]?.try &.as_i
-                fps = fmt_info["fps"]?.try &.to_i || fmt["fps"]?.try &.as_i || 30
+
+              fps = fmt["fps"]?.try &.as_i
+
+              if fps
                 json.field "fps", fps
+              end
+
+              if height && width
+                json.field "size", "#{width}x#{height}"
+                json.field "resolution", "#{height}p"
+
+                quality_label = "#{width > height ? height : width}p"
+
+                if fps && fps > 30
+                  quality_label += fps.to_s
+                end
+
+                json.field "qualityLabel", quality_label
+              end
+
+              if fmt_info = Invidious::Videos::Formats.itag_to_metadata?(fmt["itag"])
                 json.field "container", fmt_info["ext"]
                 json.field "encoding", fmt_info["vcodec"]? || fmt_info["acodec"]
-
-                if fmt_info["height"]?
-                  json.field "resolution", "#{fmt_info["height"]}p"
-
-                  quality_label = "#{fmt_info["height"]}p"
-                  if fps > 30
-                    quality_label += "60"
-                  end
-                  json.field "qualityLabel", quality_label
-
-                  if fmt_info["width"]?
-                    json.field "size", "#{fmt_info["width"]}x#{fmt_info["height"]}"
-                  end
-                end
               end
             end
           end