--- /dev/null
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * This class is a simple simulation of a typical CMOS cellphone imager chip,
+ * which outputs 12-bit Bayer-mosaic raw images.
+ *
+ * Unlike most real image sensors, this one's native color space is linear sRGB.
+ *
+ * The sensor is abstracted as operating as a pipeline 3 stages deep;
+ * conceptually, each frame to be captured goes through these three stages. The
+ * processing step for the sensor is marked off by vertical sync signals, which
+ * indicate the start of readout of the oldest frame. The interval between
+ * processing steps depends on the frame duration of the frame currently being
+ * captured. The stages are 1) configure, 2) capture, and 3) readout. During
+ * configuration, the sensor's registers for settings such as exposure time,
+ * frame duration, and gain are set for the next frame to be captured. In stage
+ * 2, the image data for the frame is actually captured by the sensor. Finally,
+ * in stage 3, the just-captured data is read out and sent to the rest of the
+ * system.
+ *
+ * The sensor is assumed to be rolling-shutter, so low-numbered rows of the
+ * sensor are exposed earlier in time than larger-numbered rows, with the time
+ * offset between each row being equal to the row readout time.
+ *
+ * The characteristics of this sensor don't correspond to any actual sensor,
+ * but are not far off typical sensors.
+ *
+ * Example timing diagram, with three frames:
+ * Frame 0-1: Frame duration 50 ms, exposure time 20 ms.
+ * Frame 2: Frame duration 75 ms, exposure time 65 ms.
+ * Legend:
+ * C = update sensor registers for frame
+ * v = row in reset (vertical blanking interval)
+ * E = row capturing image data
+ * R = row being read out
+ * | = vertical sync signal
+ *time(ms)| 0 55 105 155 230 270
+ * Frame 0| :configure : capture : readout : : :
+ * Row # | ..|CCCC______|_________|_________| : :
+ * 0 | :\ \vvvvvEEEER \ : :
+ * 500 | : \ \vvvvvEEEER \ : :
+ * 1000 | : \ \vvvvvEEEER \ : :
+ * 1500 | : \ \vvvvvEEEER \ : :
+ * 2000 | : \__________\vvvvvEEEER_________\ : :
+ * Frame 1| : configure capture readout : :
+ * Row # | : |CCCC_____|_________|______________| :
+ * 0 | : :\ \vvvvvEEEER \ :
+ * 500 | : : \ \vvvvvEEEER \ :
+ * 1000 | : : \ \vvvvvEEEER \ :
+ * 1500 | : : \ \vvvvvEEEER \ :
+ * 2000 | : : \_________\vvvvvEEEER______________\ :
+ * Frame 2| : : configure capture readout:
+ * Row # | : : |CCCC_____|______________|_______|...
+ * 0 | : : :\ \vEEEEEEEEEEEEER \
+ * 500 | : : : \ \vEEEEEEEEEEEEER \
+ * 1000 | : : : \ \vEEEEEEEEEEEEER \
+ * 1500 | : : : \ \vEEEEEEEEEEEEER \
+ * 2000 | : : : \_________\vEEEEEEEEEEEEER_______\
+ */
+
+#ifndef HW_EMULATOR_CAMERA2_SENSOR_H
+#define HW_EMULATOR_CAMERA2_SENSOR_H
+
+#include "utils/Thread.h"
+#include "utils/Mutex.h"
+#include "utils/Timers.h"
+
+#include "Scene.h"
+#include "Base.h"
+
+namespace android {
+
+class EmulatedFakeCamera2;
+
+class Sensor: private Thread, public virtual RefBase {
+ public:
+
+ Sensor();
+ ~Sensor();
+
+ /*
+ * Power control
+ */
+
+ status_t startUp();
+ status_t shutDown();
+
+ /*
+ * Access to scene
+ */
+ Scene &getScene();
+
+ /*
+ * Controls that can be updated every frame
+ */
+
+ void setExposureTime(uint64_t ns);
+ void setFrameDuration(uint64_t ns);
+ void setSensitivity(uint32_t gain);
+ // Buffer must be at least stride*height*2 bytes in size
+ void setDestinationBuffers(Buffers *buffers);
+ // To simplify tracking sensor's current frame
+ void setFrameNumber(uint32_t frameNumber);
+
+ /*
+ * Controls that cause reconfiguration delay
+ */
+
+ void setBinning(int horizontalFactor, int verticalFactor);
+
+ /*
+ * Synchronizing with sensor operation (vertical sync)
+ */
+
+ // Wait until the sensor outputs its next vertical sync signal, meaning it
+ // is starting readout of its latest frame of data. Returns true if vertical
+ // sync is signaled, false if the wait timed out.
+ bool waitForVSync(nsecs_t reltime);
+
+ // Wait until a new frame has been read out, and then return the time
+ // capture started. May return immediately if a new frame has been pushed
+ // since the last wait for a new frame. Returns true if new frame is
+ // returned, false if timed out.
+ bool waitForNewFrame(nsecs_t reltime,
+ nsecs_t *captureTime);
+
+ /*
+ * Interrupt event servicing from the sensor. Only triggers for sensor
+ * cycles that have valid buffers to write to.
+ */
+ struct SensorListener {
+ enum Event {
+ EXPOSURE_START, // Start of exposure
+ };
+
+ virtual void onSensorEvent(uint32_t frameNumber, Event e,
+ nsecs_t timestamp) = 0;
+ virtual ~SensorListener();
+ };
+
+ void setSensorListener(SensorListener *listener);
+
+ /**
+ * Static sensor characteristics
+ */
+ static const unsigned int kResolution[2];
+ static const unsigned int kActiveArray[4];
+
+ static const nsecs_t kExposureTimeRange[2];
+ static const nsecs_t kFrameDurationRange[2];
+ static const nsecs_t kMinVerticalBlank;
+
+ static const uint8_t kColorFilterArrangement;
+
+ // Output image data characteristics
+ static const uint32_t kMaxRawValue;
+ static const uint32_t kBlackLevel;
+ // Sensor sensitivity, approximate
+
+ static const float kSaturationVoltage;
+ static const uint32_t kSaturationElectrons;
+ static const float kVoltsPerLuxSecond;
+ static const float kElectronsPerLuxSecond;
+
+ static const float kBaseGainFactor;
+
+ static const float kReadNoiseStddevBeforeGain; // In electrons
+ static const float kReadNoiseStddevAfterGain; // In raw digital units
+ static const float kReadNoiseVarBeforeGain;
+ static const float kReadNoiseVarAfterGain;
+
+ // While each row has to read out, reset, and then expose, the (reset +
+ // expose) sequence can be overlapped by other row readouts, so the final
+ // minimum frame duration is purely a function of row readout time, at least
+ // if there's a reasonable number of rows.
+ static const nsecs_t kRowReadoutTime;
+
+ static const int32_t kSensitivityRange[2];
+ static const uint32_t kDefaultSensitivity;
+
+ private:
+ Mutex mControlMutex; // Lock before accessing control parameters
+ // Start of control parameters
+ Condition mVSync;
+ bool mGotVSync;
+ uint64_t mExposureTime;
+ uint64_t mFrameDuration;
+ uint32_t mGainFactor;
+ Buffers *mNextBuffers;
+ uint32_t mFrameNumber;
+
+ // End of control parameters
+
+ Mutex mReadoutMutex; // Lock before accessing readout variables
+ // Start of readout variables
+ Condition mReadoutAvailable;
+ Condition mReadoutComplete;
+ Buffers *mCapturedBuffers;
+ nsecs_t mCaptureTime;
+ SensorListener *mListener;
+ // End of readout variables
+
+ // Time of sensor startup, used for simulation zero-time point
+ nsecs_t mStartupTime;
+
+ /**
+ * Inherited Thread virtual overrides, and members only used by the
+ * processing thread
+ */
+ private:
+ virtual status_t readyToRun();
+
+ virtual bool threadLoop();
+
+ nsecs_t mNextCaptureTime;
+ Buffers *mNextCapturedBuffers;
+
+ Scene mScene;
+
+ void captureRaw(uint8_t *img, uint32_t gain, uint32_t stride);
+ void captureRGBA(uint8_t *img, uint32_t gain, uint32_t stride);
+ void captureRGB(uint8_t *img, uint32_t gain, uint32_t stride);
+ void captureNV21(uint8_t *img, uint32_t gain, uint32_t stride);
+ void captureDepth(uint8_t *img, uint32_t gain, uint32_t stride);
+ void captureDepthCloud(uint8_t *img);
+
+};
+
+}
+
+#endif // HW_EMULATOR_CAMERA2_SENSOR_H
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