1. HDR概述

HDR(High-Dynamic Range)算法根据不同曝光的图片，合成最终HDR图片，比一般图片具有更宽的动态范围和图像细节。

一般HDR算法有两种：一种是基于不同曝光时间的连续几幅图片合现,这种方法实现简单，只要能调曝光的sensor都可以实合成一幅图片；第二种是基于同一行不同曝光，最终成一幅图片，这种方法需要sensor支持行间长短曝光。

这里使用500万分辨率摄像头芯片实现行间长短曝光实现HDR算法。

2. HDR模式传输方式

在摄像头芯片中，视频信号通过MIPI接口传输，根据MIPI协议可将长短曝光行数据，通过两个virtual channel来传输。

行间HDR数据读出时序如下：

Fram_long与Fram_short输出偏差为max short exposure。

max long exposure={帧长}-max short exposure。

3. sensor的库文件生成(.so)

Sensor的库文件需要在Linux服务器中的SDK包中编译得到，将生成的.so文件放到SDK包中的stream软件包中的Hi3516A_Stream_xxx/libs目录下。

XXXX_sensor_ctl.c实现sensor的初始化：

voidsensor_init_5M_2lan_10bit_hdr(){sensor_write_register(0x0100,0x00);sensor_write_register(0x363f,0x1c);sensor_write_register(0x3e03,0x03);sensor_write_register(0x3e08,0x00);sensor_write_register(0x3e09,0x10);sensor_write_register(0x3400,0x52);sensor_write_register(0x5000,0x21);sensor_write_register(0x5001,0x04);sensor_write_register(0x3627,0x02);sensor_write_register(0x320c,0x06);sensor_write_register(0x3f00,0xc6);sensor_write_register(0x3f01,0x04);sensor_write_register(0x3306,0x20);sensor_write_register(0x330b,0x38);sensor_write_register(0x4503,0xbb);sensor_write_register(0x3623,0x00);sensor_write_register(0x3622,0x0e);sensor_write_register(0x3630,0x34);sensor_write_register(0x3303,0x30);sensor_write_register(0x3309,0x30);sensor_write_register(0x331e,0x28);sensor_write_register(0x331f,0x28);sensor_write_register(0x3320,0x2c);sensor_write_register(0x3321,0x2c);sensor_write_register(0x3322,0x2c);sensor_write_register(0x3323,0x2c);sensor_write_register(0x5001,0x05);sensor_write_register(0x3902,0x05);sensor_write_register(0x3909,0x02);sensor_write_register(0x3907,0x00);sensor_write_register(0x3908,0x40);sensor_write_register(0x3416,0x00);sensor_write_register(0x3621,0x18);sensor_write_register(0x3627,0x04);sensor_write_register(0x3333,0x00);sensor_write_register(0x3334,0xf0);sensor_write_register(0x3662,0x82);sensor_write_register(0x3e09,0x50);sensor_write_register(0x3908,0x00);sensor_write_register(0x3620,0x62);sensor_write_register(0x5000,0x21);sensor_write_register(0x3e09,0xf0);sensor_write_register(0x3400,0x52);sensor_write_register(0x3638,0x84);sensor_write_register(0x3637,0x82);sensor_write_register(0x363f,0x0c);sensor_write_register(0x3622,0x02);sensor_write_register(0x330b,0x3c);sensor_write_register(0x363a,0x1c);sensor_write_register(0x3c00,0x41);sensor_write_register(0x3e01,0x10);sensor_write_register(0x3e05,0x00);sensor_write_register(0x3e06,0xf0);sensor_write_register(0x3221,0x80);sensor_write_register(0x4816,0x11);sensor_write_register(0x3e04,0x03);sensor_write_register(0x6000,0x21);sensor_write_register(0x320e,0x0f);//maxinttimesensor_write_register(0x320f,0x80);//maxinttimesensor_write_register(0x3e15,0x00);//maxshortexposuresensor_write_register(0x3e16,0x40);//maxshortexposuresensor_write_register(0x3c00,0x00);//[2]:0mipi->fifosensor_write_register(0x303f,0x02);//[7]:0selpll_pclksensor_write_register(0x3031,0x0a);//[3:0]10bitsensor_write_register(0x3018,0x33);//[7:5]sellane=reg+1sensor_write_register(0x3c03,0x10);//fifofor4lanesensor_write_register(0x3030,0x04);sensor_write_register(0x303d,0x01);sensor_write_register(0x303b,0x02);sensor_write_register(0x303c,0x08);sensor_write_register(0x3650,0x37);sensor_write_register(0x363f,0x0c);sensor_write_register(0x3300,0x10);sensor_write_register(0x3654,0x45);sensor_write_register(0x3902,0x45);sensor_write_register(0x3909,0x00);sensor_write_register(0x390a,0x00);sensor_write_register(0x3400,0x53);sensor_write_register(0x3039,0x10);sensor_write_register(0x303a,0x18);sensor_write_register(0x330a,0x01);sensor_write_register(0x330b,0x40);sensor_write_register(0x3306,0x80);sensor_write_register(0x3308,0x08);sensor_write_register(0x3416,0x20);sensor_write_register(0x320c,0x04);sensor_write_register(0x3907,0x03);sensor_write_register(0x3626,0x30);//0909sensor_write_register(0x5000,0x21);sensor_write_register(0x330b,0xa0);sensor_write_register(0x3630,0x24);//0x14sensor_write_register(0x3620,0x48);sensor_write_register(0x3f05,0xf0);sensor_write_register(0x320c,0x05);sensor_write_register(0x3e09,0x10);sensor_write_register(0x320d,0xa0);//25fpssensor_write_register(0x3c00,0x41);//fifoconfigsensor_write_register(0x3622,0x02);sensor_write_register(0x3638,0x83);sensor_write_register(0x3306,0x90);sensor_write_register(0x3f05,0xe0);sensor_write_register(0X3620,0X42);sensor_write_register(0x363a,0x14);sensor_write_register(0x3416,0x11);sensor_write_register(0x3334,0xa0);sensor_write_register(0x3333,0x90);sensor_write_register(0x3620,0x46);//0x66gain<2sensor_write_register(0x3303,0x48);sensor_write_register(0x3309,0x48);sensor_write_register(0x3627,0x08);sensor_write_register(0x335d,0x00);sensor_write_register(0x330e,0x10);sensor_write_register(0x303c,0x08);//halfmipispeedsensor_write_register(0x363c,0xc3);sensor_write_register(0x3010,0xe0);//closedvpoutsensor_write_register(0x300f,0xff);sensor_write_register(0x300e,0x0f);sensor_write_register(0x3635,0x38);sensor_write_register(0x3636,0x38);sensor_write_register(0x363f,0x80);sensor_write_register(0x3631,0x02);sensor_write_register(0x3637,0x82);sensor_write_register(0x3035,0xca);sensor_write_register(0x3300,0x30);sensor_write_register(0x330b,0x60);sensor_write_register(0x3f04,0x03);sensor_write_register(0x3f05,0x30);sensor_write_register(0x3633,0x1e);sensor_write_register(0x3630,0x1c);sensor_write_register(0x3622,0x06);sensor_write_register(0x0100,0x01);}

XXXX_cmos.c主要实现ISP需要的回调函数，传递参数，包括ISP、AE、AWB等。还需将变量genSensorMode赋值为WDR_MODE_2To1_LINE，以选择行间HDR模式。

//ISPfunctionHI_S32cmos_init_sensor_exp_function(ISP_SENSOR_EXP_FUNC_S*pstSensorExpFunc){memset(pstSensorExpFunc,0,sizeof(ISP_SENSOR_EXP_FUNC_S));pstSensorExpFunc->pfn_cmos_sensor_init=sensor_init;pstSensorExpFunc->pfn_cmos_sensor_exit=sensor_exit;pstSensorExpFunc->pfn_cmos_sensor_global_init=sensor_global_init;pstSensorExpFunc->pfn_cmos_set_p_w_picpath_mode=cmos_set_p_w_picpath_mode;pstSensorExpFunc->pfn_cmos_set_wdr_mode=cmos_set_wdr_mode;pstSensorExpFunc->pfn_cmos_get_isp_default=cmos_get_isp_default;pstSensorExpFunc->pfn_cmos_get_isp_black_level=cmos_get_isp_black_level;pstSensorExpFunc->pfn_cmos_set_pixel_detect=cmos_set_pixel_detect;pstSensorExpFunc->pfn_cmos_get_sns_reg_info=cmos_get_sns_regs_info;return0;}//AEfunctionHI_S32cmos_init_ae_exp_function(AE_SENSOR_EXP_FUNC_S*pstExpFuncs){memset(pstExpFuncs,0,sizeof(AE_SENSOR_EXP_FUNC_S));pstExpFuncs->pfn_cmos_get_ae_default=cmos_get_ae_default;pstExpFuncs->pfn_cmos_fps_set=cmos_fps_set;pstExpFuncs->pfn_cmos_slow_framerate_set=cmos_slow_framerate_set;pstExpFuncs->pfn_cmos_inttime_update=cmos_inttime_update;pstExpFuncs->pfn_cmos_gains_update=cmos_gains_update;pstExpFuncs->pfn_cmos_again_calc_table=cmos_again_calc_table;pstExpFuncs->pfn_cmos_get_inttime_max=cmos_get_inttime_max;return0;}//AWBfunctionHI_S32cmos_init_awb_exp_function(AWB_SENSOR_EXP_FUNC_S*pstExpFuncs){memset(pstExpFuncs,0,sizeof(AWB_SENSOR_EXP_FUNC_S));pstExpFuncs->pfn_cmos_get_awb_default=cmos_get_awb_default;return0;}HI_U8gu8SensorImageMode=SENSOR_5M_25FPS_MODE;WDR_MODE_EgenSensorMode=WDR_MODE_2To1_LINE;

与一般sensor设置曝光不同，HDR行间模式需要行间交替实现曝光时间设置，也是在XXXX_cmos.c中实现，具体函数如下：

staticHI_VOIDcmos_inttime_update(HI_U32u32IntTime){staticHI_BOOLbFirst=HI_TRUE;if(WDR_MODE_2To1_LINE==genSensorMode){if(bFirst)//shortexposure{au32WDRIntTime[0]=u32IntTime;g_stSnsRegsInfo.astI2cData[4].u32Data=(u32IntTime>>4)&0xFF;;g_stSnsRegsInfo.astI2cData[5].u32Data=(u32IntTime<<4)&0xF0;bFirst=HI_FALSE;}else//longexposure{au32WDRIntTime[1]=u32IntTime;g_stSnsRegsInfo.astI2cData[0].u32Data=(u32IntTime>>4)&0xFF;;g_stSnsRegsInfo.astI2cData[1].u32Data=(u32IntTime<<4)&0xF0;bFirst=HI_TRUE;}}else{g_stSnsRegsInfo.astI2cData[0].u32Data=(u32IntTime>>4)&0xFF;;g_stSnsRegsInfo.astI2cData[1].u32Data=(u32IntTime<<4)&0xF0;bFirst=HI_TRUE;}return;}

4.修改stream软件包的.ini文件

[sensor]Sensor_type=XXXX;sensornameMode=2;WDR_MODE_NONE=0;WDR_MODE_BUILT_IN=1;WDR_MODE_2To1_LINE=2;WDR_MODE_2To1_FRAME=3;WDR_MODE_2To1_FRAME_FULL_RATE=4...etcDllFile=libs/libsns_XXXX_2lan.so;sensorlibpath[mode]input_mode=0;INPUT_MODE_MIPI=0;INPUT_MODE_SUBLVDS=1;INPUT_MODE_LVDS=2...etcdev_attr=0;mipi_dev_attr_t=0;lvds_dev_attr_t=1;NULL=2[mipi];----------onlyformipi_dev---------data_type=1;rawdatatype:8/10/12/14bit;RAW_DATA_8BIT=0;RAW_DATA_10BIT=1;RAW_DATA_12BIT=2;RAW_DATA_14BIT=3lane_id=0|1|-1|-1|-1|-1|-1|-1|;lane_id:-1-disable[isp_p_w_picpath]Isp_x=0Isp_y=0Isp_W=2560Isp_H=1920Isp_FrameRate=25Isp_Bayer=3;BAYER_RGGB=0,BAYER_GRBG=1,BAYER_GBRG=2,BAYER_BGGR=3

5.运行stream软件

运行stream软件包中的HiIspTool.sh脚本，通过以太网卡与上位机的PQTools建立通信。

cdHi3516A_Stream_V1.0.5.0./HiIspTools.sh-a-pXXXX_5m_2lan.ini

6.运行PQ Tools

双击PQ Tools图片，弹出如下对话框，设置IP地址。

在下拉菜单中选择TTP_Stream.exe选项.

7. 结果对比

正常光照下的图片，日光灯显示模糊。

打开灯板后，无法捕捉宽动态范围的的场景，盒中的水果不能正常显示(偏黑),灯板的LED阵列无法识别，背景也非常昏暗。

开启行间HDR功能后，盒中中的水果可以清晰辨认，灯板的LED阵列也可清晰辨认，背景可见度有很大提升。