.. _changelog_v3_9_1:

v3.9.1
======

v3.9.1 adds a **LoRa** library for the Arduino Portenta, :mod:`sensor` frame-rate
control (``set_framerate()`` / ``get_framerate()``), in-place ``draw_image()``
updates, and exFAT for the Portenta, and updates :mod:`ulab` to 2.1.3 with a more
accurate interpolated LAB color table. The :mod:`ulab` bump and LAB color change
are behavior changes — read the breaking changes below.

.. contents:: On this page
   :local:
   :depth: 1

Highlights
----------

- **LoRa library** for the Arduino Portenta.
- **Frame-rate control** — :func:`sensor.set_framerate` /
  :func:`sensor.get_framerate`.
- In-place ``draw_image()`` updates and consolidated ``to_*`` / ``copy``
  / ``crop`` image operations.
- **exFAT** filesystem enabled on the Portenta.
- **Breaking:** :mod:`ulab` was updated to 2.1.3 and color conversion now uses an
  interpolated LAB table — see the breaking changes.

New features
------------

- **LoRa** — added a LoRa library for the Arduino Portenta.
- **Sensor frame rate** — added :func:`sensor.set_framerate` and
  :func:`sensor.get_framerate`.
- **draw_image** — ``image.draw_image()`` now supports in-place updates.
- **exFAT** — enabled the exFAT filesystem on the Portenta.

Other changes and improvements
------------------------------

- Centralized and improved the ``to_*`` / ``copy`` / ``crop`` image
  operations and made ``copy_to_fb`` smarter about resource use; updated the
  HM01B0 driver; updated build scripts from upstream.

Bug fixes
---------

Camera and sensors:

- Fixed the default OV5640 ``SYSTEM_CTROL0`` value in ``sleep()``, the HM01B0
  default OSC register value, and the HM01B0 pixel-clock polarity.

System:

- Low-power fixes.

Breaking API changes
--------------------

User-visible API breaks between v3.9.0 and v3.9.1. Scope: Python C-modules in
``modules/`` and Python libraries in ``scripts/libraries/``.

Both breaking changes are *behavior* changes (same API, different results) —
re-check affected scripts. Each commit hash links to its diff on GitHub.

.. _v3_9_1_ulab:

:mod:`ulab` updated to 2.1.3 *(behavior)*
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The bundled :mod:`ulab` (NumPy-like) module was updated to 2.1.3. Array/numeric
behavior follows upstream :mod:`ulab` 2.1.3; re-check scripts that depend on
version-specific :mod:`ulab` behavior.

*Commits:* `2a190f35c <https://github.com/openmv/openmv/commit/2a190f35c>`__

.. _v3_9_1_lab:

Interpolated LAB color table *(behavior)*
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Color conversion now uses an interpolated LAB table, making LAB-based
operations (color thresholds, ``rgb_to_lab`` / ``lab_to_rgb``, color
statistics) more accurate. Results differ slightly from previous releases, so
re-check and re-tune color thresholds that were calibrated against the old
table.

*Commits:* `690a39c0c <https://github.com/openmv/openmv/commit/690a39c0c>`__

.. _v3_9_1_migration:

Migration checklist
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Re-validate scripts that depend on version-specific :mod:`ulab` behavior
(:ref:`the ulab update <v3_9_1_ulab>`) and re-tune LAB-based color thresholds
against the interpolated table (:ref:`the LAB color change <v3_9_1_lab>`). All
other scripts run unchanged.