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Documentation VISION (VAPI)

Dernière mise à jour : 02/12/20


IMAGE INTERFACE

 

Summary
Interface prefix Im
Number of functions 7
Description Set of functions to manage images files

 

Prototype long cdecl ImGetInf(char* filename, void* ldv_img)
Parameters filename: name of the image file
ldv_img: pointer to a LDV_IMAGE structure
Return LDV_STATUS
Description Reads informatiuons from the file and fills in the LDV_IMAGE strucutre. Image is not loaded (see next function) but all image caracteristics such as width, height, number of planes, ... are fetched.
Comments Call ImFree to free related resources
Version VAPI 1.09 or more

 

Prototype long cdecl ImLoad(void* ldv_img)
Parameters ldv_img: pointer to LDV_IMAGE structure previously filled-in by ImGetInf
Return LDV_STATUS
Description Loads the image into memory
Comments Image data is read during this call
Version VAPI 1.09 or more

 

Prototype void cdecl ImFree(void* ldv_img)
Parameters ldv_img: pointer to LDV_IMAGE structure previously filled-in by ImGetInf
Return None
Description Frees resources allocated by ImGetInf and ImLoad
Comments .
Version VAPI 1.09 or more

Prototype long cdecl ImSave(char* filename, void* ldv_img, char* save_options) ;
Parameters filename: name of file to save image
ldv_img:  LDV_IMAGE structure defining image to save
save_options: standard options, separated by '';',(option=<value>):
fmt = <3 characters defining image format>
quality=<quality 0...100>    (JPEG)
flipflop=<0 ou 2> (0: no flip-flop, 2: Y flip-flop)   (TGA)
compression=<none or lzw> (TIF)
byteorder=<motorola or intel>  (TIF)
Return LDV_STATUS
Description Saves an image residing in memory to a file
Comments Example
status = Vapi->ImSave( "h:\\test.tif", ldv_img, "fmt=TIF;compression=LZW;byteorder=motorola" ) ;
Some options depend on the format; they may be ignored by the driver in charge of saving
Check out opnsav.vcs script for an example on the options
Version VAPI 1.09 or more

 

Prototype long cdecl ImDither(long method, long param, void* ldv_img_in, void* ldv_img_out)
Parameters method: dither method to use:
  • 0: Auto, let VISION decide
  • 1: monochrome mattrix
  • 2: grey level
  • 3: 216 colors
  • 4: dual-tone
ldv_img_in: LDV_IMAGE structure usually provided by VISION
ldv_img_out: LDV_IMAGE structure holding dithered  image
Return LDV_STATUS
Description Request VISION to dither an image using a method
Output number of planes shall be stated in variable out->Raster.fd_nplanes (1,4,8,16 ou32)
Comments
Version VAPI 1.09 or more

Prototype long cdecl ImGetStdData(void* ldv_img, char* query, char* out_data, long out_data_size) ;
Parameters ldv_img: pointer to LDV_IMAGE structure previously filled-in by ImGetInf
query: string to request standard atribute which list follows:
  • filename: filename passed to ImGetInf
out_data: string holding value of the requested attribute
out_data_size: size, in bytes, of out_data buffer
Return LDV_STATUS
Description Requests standard data on an image
Comments See optimg.ldv source code
Version VAPI 1.09 or more

Prototype long cdecl ImComputeHistogram(void* ldv_img, HISTO *histo) ;
Parameters ldv_img:  LDV_IMAGE structure defining image to compute histograms
histo: pointeur to a HISTO structure containing the result
Return LDV_STATUS
Description Requests VISION to compute histograms
Remarques .histo->norm shall be initialized to tell VISION what is the maximal value for the highest repetition frequency
See optimg.ldv source code
Version VAPI 1.09 or more



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Documentation VISION (VAPI)



IMAGE INTERFACE