Android MTK Metadata Configuration

(1) Camera_metadata Introduction

Camera API2/HAL3的核心为per-frame control，为了达成这个目标产生了metadata的机制.metadata一共分为三类;
Control(request):
当APK query出static metadata后，可以从中作总结想要的控制
Dynamic(result):
当Hal层收到control metadata后，设定进ISP最终产生对应的结果
Static(charateristics):
描述此logcial device的规格与提供的功能

(2) Loading Static metadata

Camera static metadata再camerahalserver进程驱动就会进行加载，再onEnumerateDevicesLocked中会去分别加载相关的static_metadata；主要就是分为两类

auto CameraDeviceManagerImpl::
onEnumerateDevicesLocked() -> android::status_t{
...
    sizet const deviceNum = pHalDeviceList->searchDevices();//加载sensor&3A相关的 static metadata
    
    pMetadataProvider = IMetadataProvider::create(instance);//加载其他的static metadata
}

(1) 加载 sensor & 3A相关的static metadata

vendor/mediatek/proprietary/hardware/mtkcam/utils/LogicalCam/HalLogicalDeviceList.cpp searchDevices
vendor/mediatek/proprietary/hardware/mtkcam/utils/LogicalCam/HalLogicalDeviceList.cpp createDeviceMap
vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/common/v1_1/HalSensorList.cpp searchSensors

HalSensorList::EnumInfo const*
HalSensorList::
addAndInitSensorEnumInof_Locked(
    IMGSENSOR_SENSOR_IDX eSensorDev,
    MUINT                eSensorType,
    char                 *szSensorDrvName){
...   
    buildStaticInfo(rEnumInfo,rEnumInfo.mMetadata);
...
}

最终会通过addSensorMetadata()->buildStaticInfo()从camera metadata配置文件加载sensor与3A相关的static metadata或者自动生成特定的static metadata。在Android Q中首先会通过impBuildStaticInfo_v1这一路进行加载，然后回调用impBuildStaticInfo兼容Android P，加载自动生成的metadata，最后调用impBuildStaticInfo_v1_overwrite,加载需要强制复写的metadata，如下

MBOOL
HalSensorList::
buildStaticInfo(Info const& rInfo, IMetadata& rMetadata) const
{

    if( !impBuildStaticInfo_v1(rInfo, rMetadata) ) //加载Android Q架构的metadata

    if( !impBuildStaticInfo(rInfo, rMetadata)) //兼容加载Android P架构的metadata
    
    //Sensor manual add tag_list  //加载自动产生的metadata
    IMetadata::IEntry entryA(MTK_MULTI_CAM_FEAUTRE_SENSOR_MANULA_UPDATED);
    entryA.push_back((MINT64)MTK_SENSOR_INFO_ACTIVE_ARRAT_REGION, Type2Type<MUINT64>());

    impBuildStaticInfo_v1_overwrite(rInfo, rMetadata);//提供强制修改metadata的接口
}

impBuildStaticInfo_v1加载类型

Android Q的加载类型主要有

static
char const*const
kCommonStaticMetadataNames[] = {
    // MODULE
    "CAMERA",
    "CONTROL_AE",
    "CONTROL_AF",
    "CONTROL_AWB",
    "TUNNING",
    "FLASHLIGHT",
    "SENSOR",
    "LENS",
    // // PROJECT
    // "AVAILABLE_KEYS",
    // "FEATURE",
    // "MULTICAM",
    // "REQUEST",
    // "SCALER",
    // "VENDOR",
    NULL
};
static 
char const* const
kPlatformStaticMetadataNames[] = 
{
    "MODULE",
    "LENS",
    // "MOD_OVERWRITE"
    // "PROJECT",
    // // "PRO_OVERWRITE"
    NULL
};

impBuildStaticInof加载类型

impBuildStaticInfo()兼容Android P架构，加载的是Android P类型的metadata，主要类型是

static 
char const* const
kStaticMetadataTypeNames[] = 
{
    "LENS",
    "SENSOR",
    "TUNNING_3A",
    "FLASHLIGHT",
    "SCALER",
    "FEATURE",
    "CAMERA",
    "REQUEST",
    NULL
};

impBuildStaticInfo_v1_overwrite加载类型

impBuildStaticInfo_v1_overwrite提供强制修改metadata的接口，加载的类型是[MOD_OVERWRITE]

static 
char const* const
kPlatformOverwriteStaticMetadataNames[] = 
{
    // "MODULE"
    // "LENS",
    "MOD_OVERWRITE",
    // "PROJECT",
    // // "PRO_OVERWRITE"
    NULL
};

加载类型与metadata的对应关系

以impBuildStaticInfo为例，介绍加载类型是如何对应上配置中的metadata

static 
MBOOL
impBuildStaticInfo(
    Info const&    rInfo,
    IMetadata&     rMetadata ){
...
    String8 const s8Symbol_Sensor = String8::format("%s_DEVICE_%s_%s", PREFIX_FUNCTION_STATIC_METADATA, 
    pTypeName, rInfo.getSensorDrvName().string());
    status = impConstructStaticMetadata_by_SymbolName(s8Symbol_sensor, rInfo, rMetadata);

    String8 const s8Symbol_Common = String8::format("%s_DEVICE_%s_%s", PREFIX_FUNCTION_STATIC_METADATA, 
    pTypeName, "COMMON");
    status = impConstructStaticMetadata_by_SymbolName(s8Symbol_Common , rInfo, rMetadata);
}

上面部分使用类型等参数从camera metadata配置文件中找到对应文件中的函数指针进行加载，
String8::format("%s_DEVICE_%s_%s", PREFIX_FUNCTION_STATIC_METADATA, pTypeName, rInfo.getSensorDrvName().string());
以LENS类型为例，pTypeName = “LENS”, rInfo.getSensorDevName表示sensorName，
对应的函数指针即
STATIC_METADATA2_BEGIN(DEVICE,LENS,SENSOR_DRVNAME_IMX135_MIPI_RAW),
对应加载的配置文件即
config_static_metadata.lens.imx135mipiraw.h
HalSensorList.cpp加载sensor与3A的metadata，主要就是通过impConstructStaticMetadata_by_SymbolName函数去open对应的so库，这里是"libcam.halsensor.so"

MBOOL
impConstructStaticMetadata_by_SymbolName(
    String8 const& s8Symbol,
    Info const&    rInfo,
    IMetadata&     rMetadata){
...
    Sting8 const s8LibPath = String8::format("libcam.halsensor.so");
    void *handle = ::dlopen(s8LibPath.string(), RTLD_GLOBAL);
    
}

metadata文件的命令主要有三种，
“config_request_metadata_*.h”、" config_static_metadata_ *. h"、“config_static_metadata. * .h”;

libcam.halsensor.so默认会加载libcam.halsensor.custom.a这个static lib，而这个static lib加载的则是"config_static_metadata.*.h"类型的文件；类似
config_static_metadata.lens.imx135mipiraw.h
config_static_metadata.project.camera.imx135mipiraw.h
config_static_metadata.project.flashlight.imx135mipiraw.h
config_static_metadata.sensor.imx135mipiraw.h等
vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/mtxxx/custom/Android.mk

#define my-all-config.sensor-metadata-under
$(patsubst ./%,%, \
    $(shell find $(1) -maxdepth 4 \( -name "config_static_metadata.*.h") \) -and -not -name ".*") \
    )
#endef

(2) 加载其他类型的static metadata

上述说到除了生成libcam.halsensor.custom.a类型的metadata，还剩下"config_request_metadata_* .h"、" config_static_metadata_ * . h"两类；其他类型的主要是指" config_static_ metadata_ * . h"

status_t
MetadataProvider::
onCreate()
{
...
    status = (mVersion==0)?
        constructStaticMetadata(pMetadataConverter, mpStaticCharacteristics, mpHALMetadata):
        constructStaticMetadata_v1(pMetadataConverter, mpStaticCharacteristics, mpHALMetadata);
}

constructStaticMetadata是Android P的加载流程，Android Q开始默认走的是constructStaticMetadata_v1这一路函数，同加载Sensor与3A metadata一样，这类同样会调用到impConstructStaticMetadata_v1进行配置文件中的static metadata记载，再updata(mtkMetadata)中会自动生成特定的metadata；
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/metadataprovider/constructStaticMetadata.cpp

impConstrucStaticMetadata_by_SymbolName会去加载so库，constructStaticMetadata.cpp加载的默认路径的so，这里加载的时libmtkcam_metastore.so;

status_t
MetadataProvider::
impConstructStaticMetadata_by_SymbolName(
    String8 const&  s8Symbol,
    IMetadata  &metadata){
    typedef status_t (*PFN_T)(
        IMetadata &   metadata,
        Info const&   info);
    PFN_T pfn = (PFN_T)::dlsym(RTKD_DEFAULT, s8Symbol.string());
    
}

libmtkcam_metastore.so加载了libmtkcam_metastore.static.custom.a，默认会加载"config_static_metadata_*.h"类型,类似
config_static_metadata_feature.h
config_static_metadata_request_commonType.h
config_static_metadata_scaler.h
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/metadataprovider/custom/Android.mk

#define my-all-config.metadata-under
$(patsubst ./%,%, \
  $(shell if [ 0d $(1) ]; then find $(1) -maxdepth 4 \( name  'config_static_metadata_*.h' \) -and -not -name '.*'; fi) \
)

impConstructStaticMetadata_v1()加载类型

impConstructStaticMetadata_v1()也保留了向前兼容Android P版本的metadata配置，在metadata配置中可以直接按Android P的结构进行配置，这部分加载的类型主要是

static
char const*const
kCommonStaticMetadataNames[] = 
{
    // // MODULE
    // "CAMERA",
    // "CONTROL_AE",
    // "CONTROL_AF",
    // "CONTROL_AWB",
    // "TUNNING",
    // "FLASHLIGHT",
    // "SENSOR",
    // "LENS",
    // PROJECT
    "AVAILABLE_KEYS",
    "AVAILABLE_KEYS_VENDOR",
    "AVAILABLE_KEYS_CUSTOM",
    "FEAUTRE",
    "MULTICAM",
    "REQUEST",
    "SCALER",
    "VENDOR",
    "CUSTOM",
    NULL
};

static
char const*const
kPlatformStaticMetadataNames[] = 
{
    // "MODULE",
    // "LENS",
    // // "MOD_OVERWRITE"
    "PROJECT",
    // "PRO_OVERWRITE"
    NULL
};

impConstructStaticMetadata_v1_ext()加载类型

加载的是可选的平台相关的配置，对应的加载类型是

static 
char const* const
kPlatformOptionalStaticMetadataNames[] = 
{
    "AVAILABLE_KEYS",
    "VENDOR",
    "CUSTOM",
    NULL
};

(3) request相关的static metadata

如上，最后还剩下"config_request_metadata_* .h"类型的static metadata ；
当APK调用CameraDevice.createCaptureRequest(eg:CameraDevice.TEMPLATE_PREVIEW)，会触发RequestTempalte的加载过程，通过HIDL接口调用到CameraDevice3SessionImpl.cpp中的constructDefaultRequestSettings()方法并创建TemplateRequest实例
vendor/mediatek/proprietary/hardware/mtkcam3/main/hal/device/3.x/device/CameraDevice3SessionImpl.cpp

Return<void>
ThisNamespace::
constructDefaultRequestSettings(RequestTemplate type, constructDefaultRequestSettings_cb_hidl_cb)
{
    ITemplateRequest* obj = NSTemplateRequestManager::valueFor(getInstanceId());
    if (obj == nullptr){
        obj = ITemplateRequest::getInstance(getInstanceID());
        NSTemplateRequestManager::add(getInstanceId(),obj);
    }
    CameraMetadata metadata;
    {
        camera_metadata const* p_camera_metadata = obj->getData(static_cast<int>(type));
    }
}

在ITemplateRequest的getIstance方法中会进行Template.onCreate()的创建动作，紧着调用constructRequsetMetadata加载TempalteRequest还是与之前一样，impConstructRequestMetadata()加载的时配置文件中的TemplateRequest信息，updata()是自动生成的TemplateRequest信息
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/templateRequest/TemplateRequest.cpp

TemplateRequest::
constuctRequestMetadata(
     int const           requestType,
     camera_metadata*&   rpMetadata,
     IMetadata&          rMtkMetadata){
     MY_LOGD("constructRequestMetadata");
    
    //-----(1)-----//
     if( OK != (status = impConstructRequestMetadata(rMtkMetadata, rquestType)) ){
         MY_LOGE("Unable evaluate the size for camera staic info -status[%s(%d)]\n",::strerror(-status), -status);
         return status;
     }
     //-----(2)-----/
     //overwrite
     updateData(rMtkMetadata);
    
}

RequestTemplate类型：
CAMERA3_TEMPLATE_PREVIEW
CAMERA3_TEMPLATE_STILL_CAPTURE
CAMERA3_TEMPLATE_VIDEO_RECORD
CAMERA3_TEMPLATE_VIDEO_SNAPSHOT
CAMERA3_TEMPLATE_ZERO_SHUTTER_LAG
impConstructRequestMetadata加载的是默认的搜索路径的so们这里加载的是libmtkcam_metastore.so，这个动态库会加载libmtkcam_metastore.requset.custom.a，它会从metadata配置中加载名为"config_request_metadata_*.h"类型的文件,主要是
config_request_metadata_.h
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/templateRequest/custom/Android.mk

#define my-all-config.metadata-under
$(patsubst ./%,%, \
  $(shell if [ 0d $(1) ]; then find $(1) -maxdepth 4 \( name  'config_request_metadata_*.h' \) -and -not -name '.*'; fi) \
)

Android Q上通过COMMON_HIERARCHY这个宏开关控制走Android Q的Flow，在Andorid Q架构上PLATFORM目录与PROJECT目录一般不妨REQUEST TEMPLATE数据
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/templateRequest/custom/TempalteRequest.cpp

#ifdef COMMON_HIERARCHY
    //
    int32_t result = 0;
    {
        String8 const s8Symbol_Common = String8::format("%s_COMMON_%s", PREFIX_FUNCTION_REQUEST_METADATA, "COMMON");
        status = impConstructRequestMetadata_by_SymbolName(s8Symbol_Common, metadata, requestType);
        if( !status ) result|=COMMON_COMMON;
        String8 const s8Symbol_Sensor = String8::format("%s_COMMON_%s", PREFIX_FUNCTION_REQUEST_METADATA, nInfo.getSensorDrvName());
        status = impConstructRequestMetadata_by_SymbolName(s8Symbol_Sensor , metadata, requestType);
        if( !status ) result|=COMMON_SENSOR;
    }
    //
    {
        String8 const s8Symbol_Common = String8::format("%s_DEVICE_%s", PREFIX_FUNCTION_REQUEST_METADATA, "DEFAULT");
        status = impConstructRequestMetadata_by_SymbolName(s8Symbol_Common, metadata, requestType);
        if( !status ) result|=PLATFORM_COMMON;
        String8 const s8Symbol_Sensor = String8::format("%s_DEVICE_%s", PREFIX_FUNCTION_REQUEST_METADATA, nInfo.getSensorDrvName());
        status = impConstructRequestMetadata_by_SymbolName(s8Symbol_Sensor , metadata, requestType);
        if( !status ) result|=PLATFORM_SENSOR;
    }
    //
    {
        String8 const s8Symbol_Sensor = String8::format("%s_PROJECT_%s", PREFIX_FUNCTION_REQUEST_METADATA, nInfo.getSensorDrvName());
        status = impConstructRequestMetadata_by_SymbolName(s8Symbol_Sensor , metadata, requestType);
        if( !status ) result|=PROJECT_SENSOR;
    }
    META_LOGD("%s: load status(0x%x)", "TemplateRequest", result);

(3) How to config metadata

(O - > Android 8 P - > Andorid 9 Q - > Android 10, R - > Android 11)
Android Q版本加载的metadata配置文件路径如下图：
Android 会先加载COMMON,再加载PLATFORM目录下的metadata，再加载PROJECT目录。Project目前很少用到；后面加载的会覆盖前面加载的metadata或者前面加载的metadata基础上追加

	Path	Priority
PROJECT	CUSTOM\$(PROJECT)\hal\imgsensor_metadata\common [PROJECT_COMMON] CUSTOM\$(PROJECT)\hal\imgsensor_metadata\imx_mipi_raw [PROJECT_SENSOR]	High
PLATFORM	CUSTOM\$(PROJECT)\hal\imgsensor_metadata\common [PALTFORM_COMMON] CUSTOM\$(PROJECT)\hal\imgsensor_metadata\imx_mipi_raw [PALTFORM_SENSOR]	Mid
PROJECT	CUSTOM\$(PROJECT)\hal\imgsensor_metadata\common [COMMON_COMMON] CUSTOM\$(PROJECT)\hal\imgsensor_metadata\imx_mipi_raw [COMMON_SENSOR]	Low

在同级目录下的加载顺序则为先COMMON目录，紧接着是PLATFORM目录，最后是PROJECT目录，对于某些tag，并不希望直接覆盖前面已经加载的tag对应的Metadata，那么则需要使用APPEND_METADATA_BEGIN/APPEND_METADATA_END接口。如在PLATFORM_SENSOR目录下希望增加MTK_REQUSET_AVAILABLE_REQUEST_KEYS中的key，如果直接使用CONFIG_METADATA_BEGIN/CONFIG_METADATA_END接口，就会直接覆盖COMMON_COMMOM中的config_static_metadata_availableKey.h加载的所有MTK_REQUEST_AVAILABLE_REQUEST_KEYS，最终可能只剩下PLATFORM_SENSOR中增加的这一个。

(1) COMMON_COMMON

该目录结构如下图，主要配置TemplateRequest，以及所有平添通用的3A或者metadta配置，该文件夹会最先被加载
vendor/mediatek/proprietary/custom/common/hal/imgsensor_metadata/common/

config_request_metadata_.h
config_static_metadata.ae.h
config_static_metadata.af.h
config_static_metadata.awb.h
config_static_metadata.camera.h
config_static_metadata.flashlight.h
config_static_metadata.tunning.h
config_static_metadata_availableKeys.h
config_static_metadata_custom.h
config_static_metadata_feature.h
config_static_metadata_multicam.h
config_static_metadata_request.h
config_static_metadata_scaler.h
config_static_metadata_vendor.h
//config_request_metadata_.h:配置 Template Request, android.*/com.mediatek.*

config_static_metadata.ae.h：配置CONTROL_AE类型的Metadata，第一个参数COMMON和最后一个参数COMMON表示
位于COMMON-COMMON目录下(后面都参考此规则)，第二个参数表示类型；
android.control.ae*
STATIC_METADATA_BEGIN(COMMON, CONTROL_AE, COMMON)
//--------------------------------------------
//android.control.ae*
//--------------------------------------------
android.control.af*
STATIC_METADATA_BEGIN(COMMON, CONTROL_AF, COMMON)
//--------------------------------------------
//android.control.af*
//--------------------------------------------

(2) COMMON_SENSOR

该目录结构如下，主要配置的是特定sensor相关的信息，所有平台都通用的camera sensor属性
vendor/mediatek/proprietary/custom/common/hal/imgsensor_metadata/sensor/imx_mipi_raw

config_static_metadata.sensor.imxmipiraw.h

(3) PLATFORM_COMMON

该目录下的文件结构如下所示，以DEVICE开头的都是Android P的Metadata加载方式，只有按照Android Q的方式没有加载到数据时才会使用
vendor/mediatek/proprietary/custom/mt6761/hal/imgsensor_metadata/common/

config_static_metadata.lens.h
config_static_metadata.project.flashlight.h
config_static_metadata.sensor.h
config_static_metadata.tunning_3a.h
config_static_metadata_common.h
config_static_metadata_feature.h
config_static_metadata_project.h
config_static_metadata_request_commonType.h
config_static_metadata_scaler.h

config_static_metadata_project.h 配置PROJECT类型的Metadata，位于PLAFTOFMR目录下目前存放了
PLATFORM通用的stream configuration
STATIC_METADATA2_BEGIN(PLATFORM, PROJECT, DEFAULT)
//--------------------------------------------
//android.requset

(4) PLATFORM_SENSOR

文件结构如下，该目录配置的时Platform中Camera Sensor特有的camera metadata配置
size=4>vendor/mediatek/proprietary/custom/mt6761/hal/imgsensor_metadata/imx_mipi_raw/

config_static_metadata.lens.imxmipiraw.h
config_static_metadata.module.imxmipiraw.h
config_static_metadata_availableKeys.h
config_static_metadata_custom.h
config_static_metadata_project.h
config_static_metadata_vendor.h

config_static_metadata_availableKeys.h 配置的是AVAILABLE_KEYS类型的Metadata，可以在这里添加自定义的Vendor Tag(sensor 特有的)
STATIC_METADATA2_BEGIN(PLATFORM, AVAILABLE_KEYS, SENSOR_DRVNAME_IMX_MIPI_RAW)
//--------------------------------------------
//android.requset

config_static_metadata_custom.h 配置的是CUSTOMER类型的Metadata，可以在这里添加自定义的Metadata(sensor特有的): com.xxx.*
STATIC_METADATA2_BEGIN(PLATFORM, CUSTOM, SENSOR_DRVNAME_IMX_MIPI_RAW)
//--------------------------------------------
//com.xxx.*

config_static_metadata_project.h 配置的是PROJECT类型的Metadata，可以在这里添加Stream Configuration
STATIC_METADATA2_BEGIN(PLATFORM, PROJECT, SENSOR_DRVNAME_IMX_MIPI_RAW)
//--------------------------------------------
//android.requset
config_static_metadata_vendor.h 配置的是VENDOR类型的Metadata，目前用于MTK 的Vendor Tag

STREAM 流的配置

HAL_PIXEL_FORMAT_BLOB表示Picture-size，必须是16 align，最大必须填到跟sensor的szie小于3%的差距，宽高比位标准4:3或16:9
HAL_PIXEL_FORMAT_YCbCr_420_888用于preview、video size，只要配置了YCbCr_420_888 output，同时需要配置相同的BLOB size，HAL_PIXEL_FORMAT_YCbCr_420_888的input config用于支持yuv-reporcessing
HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED则是用于private-reporcessing,仅用于input配置，不需要output，反而回引起问题
HAL_PIXEL_FORMAT_RAW16 只需要填一組output config, size同sensor size，支持拍raw图

若是有支援reprocessing, 则需要定义如下

CONFIG_METADATA_BEGIN(MTK_REPROCESS_MAX_CAPTURE_STALL)
       CONFIG_ENTRY_VALUE(2 , MINT32)
CONFIG_METADATA_END()

CONFIG_ENTRY_VALUE(HAL_PIXEL_FORMAT_YCbCr_420_888, MINT64)
CONFIG_ENTRY_VALUE(4608, MINT64)
CONFIG_ENTRY_VALUE(3456, MINT64)
CONFIG_ENTRY_VALUE(MTK_SCALER_AVAILABLE_STREAM_CONFIGURATIONS_OUTPUT, MINT64)
CONFIG_ENTRY_VALUE(66666666, MINT64)
CONFIG_ENTRY_VALUE(0, MINT64) //CTS testStreamConfigurationMap

min frame duration 表示size streaming出的情況下, frame 与 frame之间的最短duration
stall duration 表示size因为后处理所要付出的额外时间 (例如jpeg的encode)
min frame duration 影响rrzo的大小，影响p1的出图规则(正常rrzo要小于picture size)(p1→p2 p2a 将raw图转yuv)
mtkcam3/pipeline/policy/config/mtkcam-P1HwSettingPolicy configP1HwSetting minDuration
mtkcam3/pipeline/policy/FeatureSettingPolicy.cpp evaluateCaptureSetting needCaptureNode
mtkcam3/pipeline/policy/requset/P2NodeDecisionPolicy.cpp decideStreamOut
sensor imgo im2go输出的都是raw图；preview只出im2go；capture两个都出(imgo 纯raw图)
P1Node负责输出raw图；P2CaptureNode主要负责拍照的frame的处理；P2StreamingNode主要负责录像预览的数据处理；
JpegNode的输入时main YUV、Thumbnail YUV及metadata，输出是Jpeg及App metadata

Slow Motion功能的配置

首先得确保再ProjectConfig.mk中 MTK_SLOW_MOTION_VIDEO_SUPPORT = yes

config_static_metadata_availablekeys.h

    APPEND_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_RESULT_KEYS)//new hidden
        //APPEND_ENTRY_VALUE(MTK_SMVR_FEATURE_SMVR_RESULT, MINT32)
    APPEND_METADATA_END()
    //==========================================================================
    APPEND_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS)//new hidden
        APPEND_ENTRY_VALUE(MTK_CONTROL_AVAILABLE_HIGH_SPEED_VIDEO_CONFIGURATIONS, MINT32)
    APPEND_METADATA_END()

config_static_metadata_project.h

    CONFIG_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_CAPABILITIES)//new
        CONFIG_ENTRY_VALUE(MTK_REQUEST_AVAILABLE_CAPABILITIES_CONSTRAINED_HIGH_SPEED_VIDEO, MUINT8)
    CONFIG_METADATA_END()
	//==========================================================================
    CONFIG_METADATA_BEGIN(MTK_CONTROL_AVAILABLE_HIGH_SPEED_VIDEO_CONFIGURATIONS)//new hidden
       CONFIG_ENTRY_VALUE(1920, MINT32)    // width
       CONFIG_ENTRY_VALUE(1080, MINT32)    // height
       CONFIG_ENTRY_VALUE(  30, MINT32)    // fps_min
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_max
       CONFIG_ENTRY_VALUE(   4, MINT32)    // batch_size_max
       CONFIG_ENTRY_VALUE(1920, MINT32)    // width
       CONFIG_ENTRY_VALUE(1080, MINT32)    // height
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_min
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_max
       CONFIG_ENTRY_VALUE(   4, MINT32)    // batch_size_max
       CONFIG_ENTRY_VALUE(1280, MINT32)    // width
       CONFIG_ENTRY_VALUE( 720, MINT32)    // height
       CONFIG_ENTRY_VALUE(  30, MINT32)    // fps_min
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_max
       CONFIG_ENTRY_VALUE(   4, MINT32)    // batch_size_max
       CONFIG_ENTRY_VALUE(1280, MINT32)    // width
       CONFIG_ENTRY_VALUE( 720, MINT32)    // height
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_min
       CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_max
       CONFIG_ENTRY_VALUE(   4, MINT32)    // batch_size_max
    CONFIG_METADATA_END()

以上是google AOSP 120fps的配置，MTK提供SMVR功能，SMVR与google AOSP不能同时配置，会导致慢动作crash，项目中有遇到前摄VTS测不过，使用原生接口有问题，后来就改成了MTK SMVR Batch Mode

SMVR(Slow Motion Video Record)，MTK支持三种模式
(1) constrained high speed recording
原生支持120fps，但仅能使用与Camera2 API,并且提供了 HD 和 FHD的分辨率
(2) continuos mode with batch-frames buffer
持续模式意味着，能一直录制知道用户停止，或达到内存上限，提供了240fps 和 HD resolution
(3)burst mode with dram-buffering
(3)是(2)的一个转变，提供更好帧率的录制同时减少了录制时间，提供480fps 和 HD resolution

config_static_metadata_availablekeys.h

    APPEND_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_RESULT_KEYS)//new hidden
        APPEND_ENTRY_VALUE(MTK_SMVR_FEATURE_SMVR_RESULT, MINT32)
    APPEND_METADATA_END()

config_static_metadata_vendor.h

    CONFIG_METADATA_BEGIN(MTK_SMVR_FEATURE_AVAILABLE_SMVR_MODES)//  new hidden
        CONFIG_ENTRY_VALUE(1280, MINT32)    // width
        CONFIG_ENTRY_VALUE( 720, MINT32)    // height
        CONFIG_ENTRY_VALUE( 120, MINT32)    // fps_max
        CONFIG_ENTRY_VALUE(   4, MINT32)    // p2-custom-batch-num
    CONFIG_METADATA_END()

没有慢动作选项或者效果需要注意media_profiles.xml中各sensor_id的支持能力，例如

       <EncoderProfile quality="highspeed720p" fileFormat="mp4" duration="30">
            <Video codec="h264"
                   bitRate="17000000"
                   width="1280"
                   height="720"
                   frameRate="240" />
            <Audio codec="aac"
                   bitRate="256000"
                   sampleRate="48000"
                   channels="2" />
        </EncoderProfile>

(4) How to add a vendor tag

(1) 添加客制化的vendor tag

无论是characteristic类型的，还是config阶段的session key 或者是 requset 阶段的control key都是需要进行如下定义的
vendor/mediatek/proprietary/hardware/mtkcam/include/mtkcam/utils/metadata/client/mtk_metadata_tag.h

typedef enum mtk_camera_metadata_section {
...
...
    //vendor tag
    MTK_VENDOR_TAG_SECTION          = 0x8000,
    MTK_FACE_FEATURE                = 0,
    MTK_NR_FEATURE                  = 1,
    MTK_STEREO_FEATURE              = 2,
    MTK_HDR_FEATURE                 = 3,
    MTK_MFNR_FEATURE                = 4,
    MTK_CSHOT_FEATURE               = 5,
    MTK_3A_FEATURE                  = 6,
    MTK_EIS_FEATURE                 = 7,
    MTK_STREAMING_FEATURE           = 8,
    MTK_VSDOF_FEATURE               = 9,
    MTK_MULTI_CAM_FEATURE           = 10,
    MTK_CONTROL_CAPTURE             = 11,
    MTK_BGSERVICE_FEATURE           = 12,
    MTK_CONFIGURE_SETTING           = 13,
    MTK_FLASH_FEATURE               = 14,
    MTK_SMVR_FEATURE                = 15,
    MTK_SINGLEHW_SETTING            = 16,
    MTK_ABF_FEATURE                 = 17,
    MTK_CUSTOM_FEATURE             = 18, //客制化
    MTK_VENDOR_SECTION_COUNT,
} mtk_camera_metadata_section_t;
//客制化feature段起始地址
typedef enum mtk_camera_metadata_section_start {
...
...
    MTK_SINGLEHW_SETTING_START                  = (MTK_SINGLEHW_SETTING + MTK_VENDOR_TAG_SECTION) << 16,
    MTK_ABF_FEATURE_START                       = (MTK_ABF_FEATURE + MTK_VENDOR_TAG_SECTION)   << 16,
    MTK_CUSTOM_FEATURE_START                   = (MTK_CUSTOM_FEATURE + MTK_VENDOR_TAG_SECTION)   << 16, //客制化
}
//客制化获取的metadata变量
typedef enum mtk_camera_metadata_tag{
...
...
    MTK_CUSTOM_FEATURE_SENSOR_INFO_NAME = MTK_CUSTOM_FEATURE_START, //客制化
    MTK_CUSTOM_FEATURE_END,
    ...
}mtk_camera_metadata_tag_t; 

vendor/mediatek/proprietary/hardware/mtkcam/include/mtkcam/utils/metadata/client/mtk_metadata_tag_info.inl

_IMP_SECTION_INFO_(MTK_CUSTOM_FEATURE,             "mtk.custom")

_IMP_TAG_INFO_( MTK_CUSTOM_FEATURE,
                MUINT8,     "mtk.custom")

 ...

vendor/mediatek/proprietary/hardware/mtkcam/include/mtkcam/utils/metadata/vendortag/VendorTagTable.h

static auto& _MTKCustomFeature_()
{
    static const std::map<uint32_t, VendorTag_t>
    sInst = {
        _TAG_(MTK_CUSTOM_FEATURE,
            "mtk.custom",   TYPE_BYTE),

    };
    //
    return sInst;
}
static auto& getGlobalSections()
{
    static std::vector<VendorTagSection_t>
    sMTKSections = {
        _SECTION_( "com.mediatek.facefeature",
                    MTK_FACE_FEATURE_START,
                    MTK_FACE_FEATURE_END,
                    _FaceFeature_() ),
        ...
        ...
        _SECTION_( "mtk.custom",
                MTK_CUSTOM_FEATURE_START,
                MTK_CUSTOM_FEATURE_END,
                _MTKCustomFeature_() ),

    };
    ...
}

(2) 添加requset阶段的vendor tag

vendor/mediatek/proprietary/cutom/mtxxx/hal/imgsensor_metadata/xxx_mipi_raw/config_static_metadata_availablekeys.h

APPEND_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_REQUEST_KEYS)
	APPEND_ENTRY_VALUE(MTK_CUSTOM_FEATURE, MINT32)
APPEND_METADATA_END()

(3) 添加characteristic的vendor tag

CONFIG_METADATA_BEGIN(MTK_CUSTOM_FEATURE)
    CONFIG_ENTRY_VALUE(1, MINT32)
CONFIG_METADATA_END()

(4) 添加config阶段的vendor tag(即session key)

vendor/mediatek/proprietary/cutom/mtxxx/hal/imgsensor_metadata/xxx_mipi_raw/config_static_metadata_availablekeys.h

APPEND_METADATA_BEGIN(MTK_REQUEST_AVAILABLE_SESSION_KEYS)
	APPEND_ENTRY_VALUE(MTK_CUSTOM_FEATURE, MIN32)
APPEND_METADATA_END()

或者在constructStaticMetadata.cpp去动态更新
vendor/mediatek/proprietary/hardware/mtkcam/utils/metastore/metadataprovider/constructStaticMetadata.cpp

void 
MetadataProvider::
updataData(IMetadata &rMetadata)
{
	updataStreamConfiguration(rMetadata);
	updataRecommendedStreamConfiguration(rMetadata);
	updataAfRegions(rMetadata);
	...
	{
	    IMetadata::IEntry availCharactsEntry = rMetadata.entryFor(MTK_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS);
	    availCharactsEntry.push_back(MTK_HDR_FEATURE_AVAILABLE_HDR_MODES_PHOTO, Type2Type<MINT32 >());
	    availCharactsEntry.push_back(MTK_HDR_FEATURE_AVAILABLE_HDR_MODES_VIDEO, Type2Type<MINT32 >());
	    availCharactsEntry.push_back(MTK_HDR_FEATURE_AVAILABLE_MSTREAM_HDR_MODES, Type2Type<MINT32 >());
	    rMetadata.updata(availCharactsEntry.tag(), availCharactsEntry);
	}
	...
        IMetadata::IEntry customFeature = rMetadata.entryFor(MTK_REQUEST_AVAILABLE_SESSION_KEYS);
        customFeature.push_back(MTK_CUSTOM_FEATURE, Type2Type< MINT32 >());
        rMetadata.updata(customFeature.tag(), customFeature);

(5) How to acquire vendor tag in flow

//session key pParsedAppConfiguration结构体
auto const& pParsedAppCfg       = pPipelineUserConfiguration->pParsedAppConfiguration;
IMetadata::getEntry<MUINT8>(&pParsedAppCfg->sessionParams, MTK_CUSTOM_FEATURE, value);

//RequestPtr pRequest;
IMetadata* pAppMeta = pRequest->mIMetadataApp->acquire();
IMetadata* pHalMeta  = pRequest->mIMetadataHal->acquire();
IMetadata* IMetaDynamic = pRequest->mIMetadataDynamic->acquire();

IMetadata::setEntry<MINT32>(pHalMeta, MTK_3A_ISP_BYPASS_LCE, 0);//Bypass isp module