Name
doc:LoadRawImage -- load raw image from file
Synopsis
img = doc:LoadRawImage(filename, width, height, colorspace)
Function
doc:LoadRawImage() loads an image from raw pixel data stored in an externa file. This function loads the data without any conversion. So it is usually faster than the other functions. Pixels are stored line by line from top to bottom in the color format specified by the colorspace parameter which must be set to one of the following constants:

#HPDF_CS_DEVICE_GRAY:
8 bit gray scale image. The gray scale color space describes each pixel with one byte. For each byte, 0 is maximum dark, and 255 is maximum light. The size of the image data is width * height bytes.

#HPDF_CS_DEVICE_RGB:
24 bit RGB color image. The 24 bit RGB color space describes each pixel with three bytes (red, green, blue). For each byte, 0 is maximum dark, 255 maximum light. The size of the image data is width * height * 3 bytes.

#HPDF_CS_DEVICE_CMYK
32 bit CMYK color image. The 32 bit CMYK color space describes each pixel with four bytes (cyan, magenta, yellow, black). The size of the image data is width * height * 4 bytes. For each byte, 0 is maximum dark, 255 maximum light.

When doc:LoadRawImage() succeeds, it returns the handle of an image object. Otherwise, it returns Nil and the error handler is called.

Inputs
filename
a path to an image file
width
the width of the raw pixel data
height
the height of the raw pixel data
colorspace
#HPDF_CS_DEVICE_GRAY, #HPDF_CS_DEVICE_RGB or #HPDF_CS_DEVICE_CMYK (see above)
Results
img
handle to an image
Errors
#HPDF_INVALID_DOCUMENT - An invalid document handle was set.

#HPDF_FAILED_TO_ALLOC_MEM - Memory allocation failed.

#HPDF_INVALID_COLOR_SPACE - An invalid color_space value is specified.

#HPDF_INVALID_IMAGE - The size of an image data is invalid.

#HPDF_FILE_IO_ERROR - Cannot read data from the file.


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