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：
void sensor_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); //max inttime
sensor_write_register(0x320f,0x80); //max inttime
sensor_write_register(0x3e15,0x00); //max short exposure
sensor_write_register(0x3e16,0x40); //max short exposure
sensor_write_register(0x3c00,0x00); //[2]: 0 mipi->fifo
sensor_write_register(0x303f,0x02); //[7]: 0 sel pll_pclk
sensor_write_register(0x3031,0x0a); //[3:0] 10bit
sensor_write_register(0x3018,0x33); //[7:5] sel lane=reg+1
sensor_write_register(0x3c03,0x10); //fifo for 4lane
sensor_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); //0909
sensor_write_register(0x5000,0x21);sensor_write_register(0x330b,0xa0);
sensor_write_register(0x3630,0x24); //0x14
sensor_write_register(0x3620,0x48);sensor_write_register(0x3f05,0xf0);
sensor_write_register(0x320c,0x05);sensor_write_register(0x3e09,0x10);
sensor_write_register(0x320d,0xa0); //25fps
sensor_write_register(0x3c00,0x41); //fifo configsensor_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); //0x66 gain<2
sensor_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); //half mipi speed
sensor_write_register(0x363c,0xc3);
sensor_write_register(0x3010,0xe0); //close dvp out
sensor_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。
//ISP function
HI_S32 cmos_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;
return 0;
}
//AE function
HI_S32 cmos_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;
return 0;
}
//AWB function
HI_S32 cmos_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;
return 0;
}
HI_U8 gu8SensorImageMode = SENSOR_5M_25FPS_MODE;
WDR_MODE_E genSensorMode = 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：
static HI_VOID cmos_inttime_update(HI_U32 u32IntTime)
{
static HI_BOOL bFirst = HI_TRUE;
if (WDR_MODE_2To1_LINE == genSensorMode)
{
if (bFirst) //short exposure
{
au32WDRIntTime[0] = u32IntTime;
g_stSnsRegsInfo.astI2cData[4].u32Data = (u32IntTime >> 4) & 0xFF; ;
g_stSnsRegsInfo.astI2cData[5].u32Data = (u32IntTime<<4) & 0xF0;
bFirst = HI_FALSE;
}
else //long exposure
{
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 ;sensor name Mode =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 ...etc DllFile =libs/libsns_XXXX_2lan.so ;sensor lib path [mode] input_mode =0 ;INPUT_MODE_MIPI = 0 ;INPUT_MODE_SUBLVDS = 1 ;INPUT_MODE_LVDS = 2 ...etc dev_attr = 0 ;mipi_dev_attr_t = 0 ;lvds_dev_attr_t = 1 ;NULL =2 [mipi] ;----------only for mipi_dev--------- data_type = 1 ;raw data type: 8/10/12/14 bit ;RAW_DATA_8BIT = 0 ;RAW_DATA_10BIT = 1 ;RAW_DATA_12BIT = 2 ;RAW_DATA_14BIT = 3 lane_id = 0| 1 | -1 | -1 |-1|-1|-1|-1| ;lane_id: -1 - disable [isp_p_w_picpath] Isp_x =0 Isp_y =0 Isp_W =2560 Isp_H =1920 Isp_FrameRate=25 Isp_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。
cd Hi3516A_Stream_V1.0.5.0 ./HiIspTools.sh -a -p XXXX_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。
