JPEG XS is a visually lossless, low-latency, intra-only video codec for video production workflows, standardised in ISO/IEC 21122.
A few months ago we added support for JPEG XS encoding and decoding in GStreamer, alongside MPEG-TS container support.
This initially covered progressive scan only though.
Unfortunately interlaced scan, which harks back to the days when TVs had cathode ray tube displays, is still quite common, especially in the broadcasting industry, so it was only a matter of time until support for that would be needed as well.
Long story short, GStreamer can now (with this pending Merge Request) also encode and decode interlaced video into/from JPEG XS.
When putting JPEG XS into MPEG-TS, the individual fields are actually coded separately, so there are two JPEG XS code streams per frame. Inside GStreamer pipelines interlaced raw video can be carried in multiple ways, but the most common one is an "interleaved" image, where the two fields are interleaved row by row, and this is also what capture cards such as AJA or Decklink Blackmagic produce in GStreamer.
When encoding interlaced video in this representation, we need to go twice over each frame and feed every second row of pixels to the underlying SVT JPEG XS encoder which itself is not aware of the interlaced nature of the video content. We do this by specifying double the usual stride as rowstride. This works fine, but unearthed some minor issues with the size checks on the codec side, for which we filed a pull request.
Please give it a spin, and let us know if you have any questions or are interested in additional container mappings such as MP4 or MXF, or RTP payloaders / depayloaders.