Add BBC Sounds and BBC iPlayer to supported apps (#18024)

Co-authored-by: Franck Nijhof <frenck@frenck.nl>

source/_integrations/cast.markdown

@@ -190,8 +190,9 @@ Optional:
 
 ### [Supla](https://www.supla.fi/)
 
-Example values to cast the item at <https://www.supla.fi/audio/3601824>
+#### Media parameters
 
+Mandatory:
 - `app_name`: `supla`
 - `media_id`: Supla item ID
 
@@ -201,6 +202,7 @@ Optional:
 
 #### Example:
 
+Example values to cast the item at <https://www.supla.fi/audio/3601824>
 ```yaml
 'cast_supla_to_my_chromecast':
   alias: "Cast supla to My Chromecast"
@@ -233,6 +235,95 @@ To cast media directly from a configured Plex server, set the fields [as documen
       media_content_id: 'plex://{"library_name": "Movies", "title": "Groundhog Day"}'
 ```
 
+### [BBC Sounds](https://www.bbc.co.uk/sounds)
+
+This app doesn't retrieve its own metadata, so if you want the cast interface or media player card to show titles and/or images you will have to provide the data yourself. See the examples below.
+
+#### Media parameters
+
+Mandatory:
+
+- `app_name`: `bbcsounds`
+- `media_id`: Item ID
+
+Optional:
+
+- `is_live`: Item is a live stream
+
+#### Example:
+
+Example values to cast [BBC Radio 1](https://www.bbc.co.uk/sounds/play/live:bbc_radio_one)
+
+```yaml
+  alias: "Cast BBC Sounds to My Chromecast"
+  sequence:
+    - service: media_player.play_media
+      target:
+        entity_id: media_player.my_chromecast
+      data:
+        media_content_type: cast
+        media_content_id: '
+          {
+            "app_name": "bbcsounds",
+            "media_id": "bbc_radio_one",
+            "is_live": true
+          }'
+        extra: 
+          metadata: 
+            metadataType: 0
+            title: "Radio 1"
+            images:
+              - url: "https://sounds.files.bbci.co.uk/2.3.0/networks/bbc_radio_one/background_1280x720.png"
+```
+
+### [BBC iPlayer](https://www.bbc.co.uk/iplayer)
+
+This app doesn't retrieve its own metadata, so if you want the cast interface or media player card to show titles and/or images you will have to provide the data yourself. See the examples below.
+
+Note: Media ID is NOT the 8 digit alpha-numeric in the URL, it can be found by right-clicking the playing video. E.g., [this episode](https://www.bbc.co.uk/iplayer/episode/b09w7fd9/bitz-bob-series-1-1-castle-makeover) shows:
+
+    2908kbps | dash (mf_cloudfront_dash_https)
+    b09w70r2 | 960x540
+
+With b09w70r2 being the `media_id`
+
+#### Media parameters
+
+Mandatory:
+
+- `app_name`: `bbciplayer`
+- `media_id`: Item ID
+
+Optional:
+
+- `is_live`: Item is a live stream
+
+#### Example:
+
+Example values to cast [this episode](https://www.bbc.co.uk/iplayer/episode/b09w7fd9/bitz-bob-series-1-1-castle-makeover)
+
+```yaml
+  alias: "Cast BBC iPlayer to My Chromecast"
+  sequence:
+    - service: media_player.play_media
+      target:
+        entity_id: media_player.my_chromecast
+      data:
+        media_content_type: cast
+        media_content_id: '
+          {
+            "app_name": "bbciplayer",
+            "media_id": "b09w70r2"
+          }'
+        extra: 
+          metadata: 
+            metadataType: 0
+            title: "Bitz & Bob"
+            subtitle: "Castle Makeover"
+            images:
+              - url: "https://ichef.bbci.co.uk/images/ic/1280x720/p07j4m3r.jpg"
+```
+
 ## Troubleshooting automatic discovery
 
 mDNS relies on UDP multicast, which may fail for various reasons. If none of the tips in this section helps, the recommended solution is to ensure all cast devices have static IPs assigned to them and configure a list of known hosts.