23. LDCI¶

23.1. Function Overview¶

Local Dynamic Contrast Improvement is a method to enhance image contrast and improve dark area details by adjusting histogram.

23.2. API Reference¶

CVI_ISP_SetLDCIAttr : Set LDCI parameter attribute
CVI_ISP_GetLDCIAttr : Get LDCI parameter attribute

23.2.1. CVI_ISP_SetLDCIAttr¶

【Description】

Set LDCI parameter attribute

【Syntax】

CVI_S32 CVI_ISP_SetLDCIAttr(VI_PIPE ViPipe, const ISP_LDCI_ATTR_S *pstLDCIAttr);

【Parameter】

Parameter	Description	Input/Output
ViPipe	VI_PIPE number	Input
pstLDCIAttr	DCI parameter properties	Input

【Retrun Value】

Return Value	Description
0	Success
non 0	Failure. An error code is returned. For details, see chapter Error Codes.

【Requirement】

Header files: cvi_isp.h, cvi_comm_isp.h
Library files: libisp.so

【Note】

None.

【Example】

None.

【Related Topic】

CVI_ISP_GetLDCIAttr

23.2.2. CVI_ISP_GetLDCIAttr¶

【Description】

Get LDCI parameter attribute

【Syntax】

CVI_S32 CVI_ISP_GetLDCIAttr(VI_PIPE ViPipe, ISP_LDCI_ATTR_S *pstLDCIAttr);

【Parameter】

Parameter	Description	Input/Output
ViPipe	VI_PIPE number	Input
pstLDCIAttr	DCI parameter properties	Output

【Retrun Value】

Return Value	Description
0	Success
non 0	Failure. An error code is returned. For details, see chapter Error Codes.

【Requirement】

Header files: cvi_isp.h, cvi_comm_isp.h
Library files: libisp.so

【Note】

None.

【Example】

None.

【Related Topic】

CVI_ISP_SetLDCIAttr

23.3. Data Types¶

ISP_LDCI_GAUSS_COEF_ATTR_S : LDCI Gaussian structure parameter attribute
ISP_LDCI_MANUAL_ATTR_S : LDCI parameter manual attribute
ISP_LDCI_AUTO_ATTR_S : LDCI parameter automatic attribute
ISP_LDCI_ATTR_S : LDCI parameter attribute

23.3.1. ISP_LDCI_GAUSS_COEF_ATTR_S¶

【Description】

LDCI Gaussian structure parameter attribute

【Syntax】

 typedef struct _ISP_LDCI_GAUSS_COEF_ATTR_S {
  CVI_U8 Wgt;
  CVI_U8 Sigma;
  CVI_U8 Mean;
} ISP_LDCI_GAUSS_COEF_ATTR_S;

【Member】

Member

Description

Wgt

Control the LDCI effect intensity according to the brightness, and determine the weight curve of the fusion of the LDCI result and the original image

Value range: [0x0, 0x80]

Data type: CVI_U8

Sigma

Control the LDCI effect intensity according to the brightness, and determine the weight curve of the fusion of the LDCI result and the original image

Value range: [0x0, 0xff]

Data type: CVI_U8

Mean

Control the LDCI effect intensity according to the brightness, and determine the weight curve of the fusion of the LDCI result and the original image

Value range: [0x0, 0xff]

Data type: CVI_U8

【Note】

None.

【Related Data Type and Interface】

None

23.3.2. ISP_LDCI_MANUAL_ATTR_S¶

【Description】

LDCI parameter manual attribute

【Syntax】

 typedef struct _ISP_LDCI_MANUAL_ATTR_S {
  CVI_U16 LdciStrength;
  CVI_U16 LdciRange;
  CVI_U16 TprCoef;
  CVI_U8 EdgeCoring;
  CVI_U8 LumaWgtMax;
  CVI_U8 LumaWgtMin;
  CVI_U8 VarMapMax;
  CVI_U8 VarMapMin;
  CVI_U8 UvGainMax;
  CVI_U8 UvGainMin;
  CVI_U8 BrightContrastHigh;
  CVI_U8 BrightContrastLow;
  CVI_U8 DarkContrastHigh;
  CVI_U8 DarkContrastLow;
  ISP_LDCI_GAUSS_COEF_ATTR_S LumaPosWgt;
} ISP_LDCI_MANUAL_ATTR_S;

【Member】

Member	Description
LdciStrength	Controls the LDCI enhancement effect parameters. The larger the value, the \| stronger the local contrast stretch Value range: [0x0, 0x100] Data type: CVI_U16
LdciRange	Controls the degree of contrast enhancement for high frequency areas of the image. The larger the value, the stronger the contrast of the high frequency area of the image Value range: [0x0, 0x3ff] Data type: CVI_U16
TprCoef	The smoothness of changes in the time domain of the LDCI curve. The smaller the value, the smoother the change in the time domain, and vice versa, the faster the change Value range: [0x0, 0x3ff] Data type: CVI_U16
EdgeCoring	Value range: [0x0, 0xff] Data type: CVI_U8
LumaWgtMax	Value range: [0x0, 0xff] Data type: CVI_U8
LumaWgtMin	Value range: [0x0, 0xff] Data type: CVI_U8
VarMapMax	Value range: [0x0, 0xff] Data type: CVI_U8
VarMapMin	Value range: [0x0, 0xff] Data type: CVI_U8
UvGainMax	Value range: [0x0, 0x7f] Data type: CVI_U8
UvGainMin	Value range: [0x0, 0x7f] Data type: CVI_U8
BrightContrastHigh	Value range: [0x0, 0xff] Data type: CVI_U8
BrightContrastLow	Value range: [0x0, 0xff] Data type: CVI_U8
DarkContrastHigh	Value range: [0x0, 0xff] Data type: CVI_U8
DarkContrastLow	Value range: [0x0, 0xff] Data type: CVI_U8
LumaPosWgt	Control the LDCI effect intensity according to the brightness, and determine the weight curve of the fusion of the LDCI result and the original image

【Note】

None.

【Related Data Type and Interface】

CVI_ISP_SetLDCIAttr
CVI_ISP_GetLDCIAttr

23.3.3. ISP_LDCI_AUTO_ATTR_S¶

【Description】

LDCI parameter automatic attribute

【Syntax】

 typedef struct _ISP_LDCI_AUTO_ATTR_S {
  CVI_U16 LdciStrength[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U16 LdciRange[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U16 TprCoef[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 EdgeCoring[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 LumaWgtMax[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 LumaWgtMin[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 VarMapMax[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 VarMapMin[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 UvGainMax[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 UvGainMin[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 BrightContrastHigh[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 BrightContrastLow[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 DarkContrastHigh[ISP_AUTO_ISO_STRENGTH_NUM];
  CVI_U8 DarkContrastLow[ISP_AUTO_ISO_STRENGTH_NUM];
  ISP_LDCI_GAUSS_COEF_ATTR_S LumaPosWgt[ISP_AUTO_ISO_STRENGTH_NUM];
} ISP_LDCI_AUTO_ATTR_S;

【Member】

Member	Description
LdciStrength	Controls the LDCI enhancement effect parameters. The larger the value, the \| stronger the local contrast stretch Value range: [0x0, 0x100] Data type: CVI_U16
LdciRange	Controls the degree of contrast enhancement for high frequency areas of the image. The larger the value, the stronger the contrast of the high frequency area of the image Value range: [0x0, 0x3ff] Data type: CVI_U16
TprCoef	The smoothness of changes in the time domain of the LDCI curve. The smaller the value, the smoother the change in the time domain, and vice versa, the faster the change Value range: [0x0, 0x3ff] Data type: CVI_U16
EdgeCoring	Value range: [0x0, 0xff] Data type: CVI_U8
LumaWgtMax	Value range: [0x0, 0xff] Data type: CVI_U8
LumaWgtMin	Value range: [0x0, 0xff] Data type: CVI_U8
VarMapMax	Value range: [0x0, 0xff] Data type: CVI_U8
VarMapMin	Value range: [0x0, 0xff] Data type: CVI_U8
UvGainMax	Value range: [0x0, 0x7f] Data type: CVI_U8
UvGainMin	Value range: [0x0, 0x7f] Data type: CVI_U8
BrightContrastHigh	Value range: [0x0, 0xff] Data type: CVI_U8
BrightContrastLow	Value range: [0x0, 0xff] Data type: CVI_U8
DarkContrastHigh	Value range: [0x0, 0xff] Data type: CVI_U8
DarkContrastLow	Value range: [0x0, 0xff] Data type: CVI_U8
LumaPosWgt	Control the LDCI effect intensity according to the brightness, and determine the weight curve of the fusion of the LDCI result and the original image

【Note】

None.

【Related Data Type and Interface】

CVI_ISP_SetLDCIAttr
CVI_ISP_GetLDCIAttr

23.3.4. ISP_LDCI_ATTR_S¶

【Description】

LDCI parameter attribute

【Syntax】

 typedef struct _ISP_LDCI_ATTR_S {
  CVI_BOOL Enable;
  ISP_OP_TYPE_E enOpType;
  CVI_U8 UpdateInterval;
  CVI_U8 GaussLPFSigma;
  ISP_LDCI_MANUAL_ATTR_S stManual;
  ISP_LDCI_AUTO_ATTR_S stAuto;
} ISP_LDCI_ATTR_S;

【Member】

Member	Description
Enable	LDCI module enable
enOpType	job type OP_TYPE_AUTO: automatic mode OP_TYPE_MANUAL: manual mode
UpdateInterval	Affects the parameter update terval, the larger the value, the slower the screen changes and the better the performance Value range: [0x0, 0xff] Data type: CVI_U8
GaussLPFSigma	Local filtering degree, the smaller the value, the more localized the local contrast enhancement effect, and vice versa, the more globalized Value range: [0x0, 0xff] Data type: CVI_U8
stManual	Manual Mode parameter Properties
stAuto	Auto Mode parameter Properties

【Note】

None.

【Related Data Type and Interface】

CVI_ISP_SetLDCIAttr
CVI_ISP_GetLDCIAttr