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Diffstat (limited to 'src/ipa/raspberrypi/cam_helper.h')
| -rw-r--r-- | src/ipa/raspberrypi/cam_helper.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/src/ipa/raspberrypi/cam_helper.h b/src/ipa/raspberrypi/cam_helper.h new file mode 100644 index 00000000..6c52bb52 --- /dev/null +++ b/src/ipa/raspberrypi/cam_helper.h @@ -0,0 +1,127 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2019, Raspberry Pi (Trading) Limited + * + * cam_helper.h - helper class providing camera information + */ +#pragma once + +#include <memory> +#include <string> + +#include <libcamera/base/span.h> +#include <libcamera/base/utils.h> + +#include "camera_mode.h" +#include "controller/controller.h" +#include "controller/metadata.h" +#include "md_parser.h" + +#include "libcamera/internal/v4l2_videodevice.h" + +namespace RPiController { + +/* + * The CamHelper class provides a number of facilities that anyone trying + * to drive a camera will need to know, but which are not provided by the + * standard driver framework. Specifically, it provides: + * + * A "CameraMode" structure to describe extra information about the chosen + * mode of the driver. For example, how it is cropped from the full sensor + * area, how it is scaled, whether pixels are averaged compared to the full + * resolution. + * + * The ability to convert between number of lines of exposure and actual + * exposure time, and to convert between the sensor's gain codes and actual + * gains. + * + * A function to return the number of frames of delay between updating exposure, + * analogue gain and vblanking, and for the changes to take effect. For many + * sensors these take the values 2, 1 and 2 respectively, but sensors that are + * different will need to over-ride the default function provided. + * + * A function to query if the sensor outputs embedded data that can be parsed. + * + * A function to return the sensitivity of a given camera mode. + * + * A parser to parse the embedded data buffers provided by some sensors (for + * example, the imx219 does; the ov5647 doesn't). This allows us to know for + * sure the exposure and gain of the frame we're looking at. CamHelper + * provides functions for converting analogue gains to and from the sensor's + * native gain codes. + * + * Finally, a set of functions that determine how to handle the vagaries of + * different camera modules on start-up or when switching modes. Some + * modules may produce one or more frames that are not yet correctly exposed, + * or where the metadata may be suspect. We have the following functions: + * HideFramesStartup(): Tell the pipeline handler not to return this many + * frames at start-up. This can also be used to hide initial frames + * while the AGC and other algorithms are sorting themselves out. + * HideFramesModeSwitch(): Tell the pipeline handler not to return this + * many frames after a mode switch (other than start-up). Some sensors + * may produce innvalid frames after a mode switch; others may not. + * MistrustFramesStartup(): At start-up a sensor may return frames for + * which we should not run any control algorithms (for example, metadata + * may be invalid). + * MistrustFramesModeSwitch(): The number of frames, after a mode switch + * (other than start-up), for which control algorithms should not run + * (for example, metadata may be unreliable). + */ + +class CamHelper +{ +public: + static CamHelper *create(std::string const &camName); + CamHelper(std::unique_ptr<MdParser> parser, unsigned int frameIntegrationDiff); + virtual ~CamHelper(); + void setCameraMode(const CameraMode &mode); + virtual void prepare(libcamera::Span<const uint8_t> buffer, + Metadata &metadata); + virtual void process(StatisticsPtr &stats, Metadata &metadata); + virtual uint32_t exposureLines(libcamera::utils::Duration exposure) const; + virtual libcamera::utils::Duration exposure(uint32_t exposureLines) const; + virtual uint32_t getVBlanking(libcamera::utils::Duration &exposure, + libcamera::utils::Duration minFrameDuration, + libcamera::utils::Duration maxFrameDuration) const; + virtual uint32_t gainCode(double gain) const = 0; + virtual double gain(uint32_t gainCode) const = 0; + virtual void getDelays(int &exposureDelay, int &gainDelay, + int &vblankDelay) const; + virtual bool sensorEmbeddedDataPresent() const; + virtual double getModeSensitivity(const CameraMode &mode) const; + virtual unsigned int hideFramesStartup() const; + virtual unsigned int hideFramesModeSwitch() const; + virtual unsigned int mistrustFramesStartup() const; + virtual unsigned int mistrustFramesModeSwitch() const; + +protected: + void parseEmbeddedData(libcamera::Span<const uint8_t> buffer, + Metadata &metadata); + virtual void populateMetadata(const MdParser::RegisterMap ®isters, + Metadata &metadata) const; + + std::unique_ptr<MdParser> parser_; + CameraMode mode_; + +private: + bool initialized_; + /* + * Smallest difference between the frame length and integration time, + * in units of lines. + */ + unsigned int frameIntegrationDiff_; +}; + +/* + * This is for registering camera helpers with the system, so that the + * CamHelper::Create function picks them up automatically. + */ + +typedef CamHelper *(*CamHelperCreateFunc)(); +struct RegisterCamHelper +{ + RegisterCamHelper(char const *camName, + CamHelperCreateFunc createFunc); +}; + +} /* namespace RPi */ |