IM: Image Conversion

IM - An Imaging Tool

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Image Conversion
[imImage]

Detailed Description

Converts one type of image into another. Can convert between color modes and between data types.
See im_convert.h


Enumerations

enum  imComplex2Real { IM_CPX_REAL, IM_CPX_IMAG, IM_CPX_MAG, IM_CPX_PHASE }
enum  imGammaFactor {
  IM_GAMMA_LINEAR = 0, IM_GAMMA_LOGLITE = -10, IM_GAMMA_LOGHEAVY = -1000, IM_GAMMA_EXPLITE = 2,
  IM_GAMMA_EXPHEAVY = 7
}
enum  imCastMode { IM_CAST_MINMAX, IM_CAST_FIXED, IM_CAST_DIRECT }

Functions

int imConvertDataType (const imImage *src_image, imImage *dst_image, int cpx2real, float gamma, int abssolute, int cast_mode)
int imConvertColorSpace (const imImage *src_image, imImage *dst_image)
int imConvertToBitmap (const imImage *src_image, imImage *dst_image, int cpx2real, float gamma, int abssolute, int cast_mode)

Enumeration Type Documentation

enum imComplex2Real
 

Complex to real conversions 

00029 {
00030   IM_CPX_REAL, 
00031   IM_CPX_IMAG, 
00032   IM_CPX_MAG, 
00033   IM_CPX_PHASE
00034 };

enum imGammaFactor
 

Predefined Gamma factors. Gamma can be any real number. When gamma<0 use logarithmic, when gamma>0 use exponential. gamma(x,g) = ((e^(g*x))-1)/(exp(g)-1) gamma(x,g) = (log((g*x)+1))/(log(g+1)) 

00042 {
00043   IM_GAMMA_LINEAR   = 0,
00044   IM_GAMMA_LOGLITE  = -10,
00045   IM_GAMMA_LOGHEAVY = -1000,
00046   IM_GAMMA_EXPLITE  = 2,
00047   IM_GAMMA_EXPHEAVY = 7
00048 };

enum imCastMode
 

Predefined Cast Modes

Enumerator:
IM_CAST_MINMAX  scan for min and max values
IM_CAST_FIXED  use predefied 0-max values, see Color Manipulation Color Manipulation.
IM_CAST_DIRECT  direct type cast the value. Only byte and ushort will be cropped. 
00053 {
00054   IM_CAST_MINMAX, /**< scan for min and max values */
00055   IM_CAST_FIXED,  /**< use predefied 0-max values, see \ref color Color Manipulation. */
00056   IM_CAST_DIRECT  /**< direct type cast the value. Only byte and ushort will be cropped. */
00057 };

Function Documentation

int imConvertDataType (  const imImage *  src_image,
imImage *  dst_image,
int  cpx2real,
float  gamma,
int  abssolute,
int  cast_mode
) 
 

Changes the image data type, using a complex2real conversion, a gamma factor, and an abssolute mode (modulus).
When demoting the data type the function will scan for min/max values or use fixed values (cast_mode) to scale the result according to the destiny range.
Except complex to real that will use only the complex2real conversion.
Images must be of the same size and color mode.
Returns IM_ERR_NONE, IM_ERR_DATA or IM_ERR_COUNTER, see also imErrorCodes. See also imComplex2Real, imGammaFactor and imCastMode.

im.ConvertDataType(src_image: imImage, dst_image: imImage, cpx2real: number, gamma: number, abssolute: bool, cast_mode: number) -> error: number [in Lua 5]

int imConvertColorSpace (  const imImage *  src_image,
imImage *  dst_image
) 
 

Converts one color space to another. Images must be of the same size and data type.
CMYK can be converted to RGB only, and it is a very simple conversion.
All colors can be converted to Binary, the non zero gray values are converted to 1.
RGB to Map uses the median cut implementation from the free IJG JPEG software, copyright Thomas G. Lane.
All other color space conversions assume sRGB and CIE definitions.
Returns IM_ERR_NONE, IM_ERR_DATA or IM_ERR_COUNTER, see also imErrorCodes.

im.ConvertColorSpace(src_image: imImage, dst_image: imImage) -> error: number [in Lua 5]

int imConvertToBitmap (  const imImage *  src_image,
imImage *  dst_image,
int  cpx2real,
float  gamma,
int  abssolute,
int  cast_mode
) 
 

Converts the image to its bitmap equivalent, uses imConvertColorSpace and imConvertDataType.
Returns IM_ERR_NONE, IM_ERR_DATA or IM_ERR_COUNTER, see also imErrorCodes. See also imComplex2Real, imGammaFactor and imCastMode.

im.ConvertToBitmap(src_image: imImage, dst_image: imImage, cpx2real: number, gamma: number, abssolute: bool, cast_mode: number) -> error: number [in Lua 5]


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