Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5710>
* ## Example launch line to generate annex B format AV1 stream:
* ```
* gst-launch-1.0 filesrc location=sample.av1 ! ivfparse ! av1parse ! \
- * video/x-av1,alignment=\(string\)tu,stream-format=\(string\)annexb ! \
- * filesink location=matroskamux ! filesink location=trans.mkv
+ * video/x-av1,alignment=\(string\)tu,stream-format=\(string\)obu-stream ! \
+ * matroskamux ! filesink location=trans.mkv
* ```
*
* Since: 1.20