qandroidvideodevices.cpp

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// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qandroidvideodevices_p.h"
 
#include <private/qcameradevice_p.h>
 
#include <QtCore/QLoggingCategory>
#include <QtCore/qcoreapplication.h>
#include <QtCore/private/qandroidextras_p.h>
#include <QtCore/qcoreapplication_platform.h>
#include <QJniEnvironment>
#include <jni.h>
 
static Q_LOGGING_CATEGORY(qLCAndroidVideoDevices, "qt.multimedia.ffmpeg.android.videoDevices")
 
Q_DECLARE_JNI_CLASS(QtVideoDeviceManager,
                    "org/qtproject/qt/android/multimedia/QtVideoDeviceManager");
Q_DECLARE_JNI_TYPE(StringArray, "[Ljava/lang/String;")
Q_DECLARE_JNI_CLASS(AndroidImageFormat, "android/graphics/ImageFormat");
 
QCameraFormat createCameraFormat(int width, int height, int fpsMin, int fpsMax)
{
    QCameraFormatPrivate *format = new QCameraFormatPrivate();
 
    format->resolution = { width, height };
 
    format->minFrameRate = fpsMin;
    format->maxFrameRate = fpsMax;
 
    format->pixelFormat = QVideoFrameFormat::PixelFormat::Format_YUV420P;
 
    return format->create();
}
 
QList<QCameraDevice> QAndroidVideoDevices::findVideoDevices()
{
    QList<QCameraDevice> devices;
 
    QJniObject deviceManager(QtJniTypes::className<QtJniTypes::QtVideoDeviceManager>(),
                             QNativeInterface::QAndroidApplication::context());
 
    if (!deviceManager.isValid()) {
        qCWarning(qLCAndroidVideoDevices) << "Failed to connect to Qt Video Device Manager.";
        return devices;
    }
 
    QJniObject cameraIdList = deviceManager.callMethod<QtJniTypes::StringArray>("getCameraIdList");
 
    QJniEnvironment jniEnv;
    int numCameras = jniEnv->GetArrayLength(cameraIdList.object<jarray>());
    if (jniEnv.checkAndClearExceptions())
        return devices;
 
    for (int cameraIndex = 0; cameraIndex < numCameras; cameraIndex++) {
 
        QJniObject cameraIdObject =
                jniEnv->GetObjectArrayElement(cameraIdList.object<jobjectArray>(), cameraIndex);
        if (jniEnv.checkAndClearExceptions())
            continue;
 
        jstring cameraId = cameraIdObject.object<jstring>();
 
        QCameraDevicePrivate *info = new QCameraDevicePrivate;
        info->id = cameraIdObject.toString().toUtf8();
 
        info->orientation = deviceManager.callMethod<jint>("getSensorOrientation", cameraId);
 
        int facing = deviceManager.callMethod<jint>("getLensFacing", cameraId);
 
        const int LENS_FACING_FRONT = 0;
        const int LENS_FACING_BACK = 1;
        const int LENS_FACING_EXTERNAL = 2;
 
        switch (facing) {
        case LENS_FACING_EXTERNAL:
        case LENS_FACING_BACK:
            info->position = QCameraDevice::BackFace;
            info->description = QString("Rear Camera: %1").arg(cameraIndex);
            break;
        case LENS_FACING_FRONT:
            info->position = QCameraDevice::FrontFace;
            info->description = QString("Front Camera: %1").arg(cameraIndex);
            break;
        }
 
        QJniObject fpsRangesObject =
                deviceManager.callMethod<QtJniTypes::StringArray>("getFpsRange", cameraId);
        jobjectArray fpsRanges = fpsRangesObject.object<jobjectArray>();
 
        int numRanges = jniEnv->GetArrayLength(fpsRanges);
        if (jniEnv.checkAndClearExceptions())
            continue;
 
        int maxFps = 0, minFps = 0;
 
        for (int rangeIndex = 0; rangeIndex < numRanges; rangeIndex++) {
 
            QJniObject rangeString = jniEnv->GetObjectArrayElement(fpsRanges, rangeIndex);
            if (jniEnv.checkAndClearExceptions())
                continue;
 
            QString range = rangeString.toString();
 
            range = range.remove("[");
            range = range.remove("]");
 
            auto split = range.split(",");
 
            int min = split[0].toInt();
            int max = split[1].toInt();
 
            if (max > maxFps) {
                maxFps = max;
                minFps = min;
            }
        }
 
        const static int imageFormat =
                QJniObject::getStaticField<QtJniTypes::AndroidImageFormat, jint>("YUV_420_888");
 
        QJniObject sizesObject = deviceManager.callMethod<QtJniTypes::StringArray>(
                "getStreamConfigurationsSizes", cameraId, imageFormat);
 
        jobjectArray streamSizes = sizesObject.object<jobjectArray>();
        int numSizes = jniEnv->GetArrayLength(streamSizes);
        if (jniEnv.checkAndClearExceptions())
            continue;
 
        for (int sizesIndex = 0; sizesIndex < numSizes; sizesIndex++) {
 
            QJniObject sizeStringObject = jniEnv->GetObjectArrayElement(streamSizes, sizesIndex);
            if (jniEnv.checkAndClearExceptions())
                continue;
 
            QString sizeString = sizeStringObject.toString();
 
            auto split = sizeString.split("x");
 
            int width = split[0].toInt();
            int height = split[1].toInt();
 
            info->videoFormats.append(createCameraFormat(width, height, minFps, maxFps));
        }
 
        devices.push_back(info->create());
    }
 
    return devices;
}