| C_COMPRESSED_IMG_INFO | Basic physical information of a compressed image buffer |
| C_FoundText | Search result |
| C_IMG_INFO | Structure of an image containing basic physical information |
| C_OUTPUTCONVERTERINFO | Output document converter information (ANSI) |
| C_R_IOStreamfuncs | Container structure of the IOStream callback functions |
| C_RPPERRORS | Error list item |
| C_ZONE | ZONE structure |
| CBAR_INFO | Barcode information |
| CCELL_INFO | Structure of a cell in a table |
| CCLASSIFY_INFO | Structure for information about classification |
| CCOMB_CELL_INFO | Structure of a comb-cell in a comb |
| CCUT_INFO | Structure for book images |
| COmniPageCSDK.RecPDF.Document | A PDF document |
| CHNR_BOXDATA | Character box of HNR |
| CKRECMODULEINFO | Module info |
| CLANGUAGE_INFO | Language info |
| CLETTER | The LETTER structure |
| CLSPC | Additional information about the space character |
| COmniPageCSDK.RecPDF.Manager | Manager class for the RecPDF |
| COmniPageCSDK.RecPDF.Operation | A PDF operation |
| COmniPageCSDK.RecPDF.OptDocument | A PDF document for PDF optimizing operations |
| COUTPUTCONVERTERINFOW | Output document converter information (Unicode) |
| ▼COmniPageCSDK.RecPDF.PDFException | PDF exception |
| COmniPageCSDK.RecPDF.AlreadyInitializedException | RecPDF already initialized |
| COmniPageCSDK.RecPDF.ParameterIsNullException | Null parameter |
| COmniPageCSDK.RecPDF.RecAPIError | RecAPI error |
| CPREPROC_INFO | Information about preprocessing |
| CPROGRESSMONITOR | Progress information |
| COmniPageCSDK.RecPDF.RecPDF | Main class for RecPDF |
| CRLINE | Structure of a line |
| CSEnumTypeElement | Descriptor structure of an enum type element |
| CSTATISTIC | Recognition statistics |
| CZONEDATA | ZONEDATA structure |