NAME

rgb.c - implements reading and writing sgi image files, uses io layer.

SYNOPSIS

io_glue *ig = io_new_fd( fd );
i_img *im   = i_readrgb_wiol(ig, 0); // disallow partial reads
// or 
io_glue *ig = io_new_fd( fd );
return_code = i_writergb_wiol(im, ig); 

DESCRIPTION

imsgi.c implements the basic functions to read and write portable SGI files. It uses the iolayer and needs either a seekable source or an entire memory mapped buffer.

FUNCTION REFERENCE

Some of these functions are internal.

rgb_header_unpack(header, headbuf)

Unpacks the header structure into from buffer and stores in the header structure.

header - header structure
headbuf - buffer to unpack from

rgb_header_pack(header, headbuf)

Packs header structure into buffer for writing.

header - header structure
headbuf - buffer to pack into

i_readsgi_wiol(ig, partial)

Read in an image from the iolayer data source and return the image structure to it. Returns NULL on error.

ig     - io_glue object
length - maximum length to read from data source, before closing it -1 
         signifies no limit.

i_writergb_wiol(img, ig)

Writes an image in targa format. Returns 0 on error.

img    - image to store
ig     - io_glue object