pipeline: ipa: raspberrypi: Refactor and move the Raspberry Pi code

Split the Raspberry Pi pipeline handler and IPA source code into common
and VC4/BCM2835 specific file structures.

For the pipeline handler, the common code files now live in
src/libcamera/pipeline/rpi/common/
and the VC4-specific files in src/libcamera/pipeline/rpi/vc4/.

For the IPA, the common code files now live in
src/ipa/rpi/{cam_helper,controller}/
and the vc4 specific files in src/ipa/rpi/vc4/. With this change, the
camera tuning files are now installed under share/libcamera/ipa/rpi/vc4/.

To build the pipeline and IPA, the meson configuration options have now
changed from "raspberrypi" to "rpi/vc4":

meson setup build -Dipas=rpi/vc4 -Dpipelines=rpi/vc4

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/src/ipa/rpi/controller/lux_status.h b/src/ipa/rpi/controller/lux_status.h
new file mode 100644
index 00000000..5eb9faac
--- /dev/null
+++ b/src/ipa/rpi/controller/lux_status.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2019, Raspberry Pi Ltd
+ *
+ * lux_status.h - Lux control algorithm status
+ */
+#pragma once
+
+/*
+ * The "lux" algorithm looks at the (AGC) histogram statistics of the frame and
+ * estimates the current lux level of the scene. It does this by a simple ratio
+ * calculation comparing to a reference image that was taken in known conditions
+ * with known statistics and a properly measured lux level. There is a slight
+ * problem with aperture, in that it may be variable without the system knowing
+ * or being aware of it. In this case an external application may set a
+ * "current_aperture" value if it wishes, which would be used in place of the
+ * (presumably meaningless) value in the image metadata.
+ */
+
+struct LuxStatus {
+	double lux;
+	double aperture;
+};