NAME

ilFeedFromImage() − add to the pipe a producer that reads an image in strips

SYNOPSIS

ilBool
ilFeedFromImage (

ilPipe pipe,

ilObject image,

long height,

long stripHeight,

ilBool constantStrip);

DESCRIPTION

ilFeedFromImage() adds to the pipe a producer that reads bits from an image.  This allows the caller to feed pixels into a pipe in strips (horizontal slices of the image).  Refer to ilAddPipeElement(3X) for more information on strips.  To execute this pipe, you use ilFeedPipe() instead of ilExecutePipe().  If ilExecutePipe() is used an IL_ERROR_PIPE_NOT_FED error is returned. 

pipe is a pipe created by ilCreatePipe(). 

image is an ilObject data structure (of the type ilClientImage or ilInternalImage) that points to the image. 

height is the total height of the resulting image

stripHeight is the maximum value of nLines that can be passed to ilFeedPipe() when it executes this pipe; see ilFeedPipe(3X). 

constantStrip is TRUE if all strips, are stripHeight lines high, except for the last strip.  The last strip contains whatever lines remain, so it is allowed to be less than stripHeight lines high. 

EXAMPLE

The following example creates a pipe producer that will feed 16 lines of an image into the pipe on each subsequent call of ilFeedPipe(). 

ilPipe pipe;

ilClientImage image;

long height;

ilImageInfo *pClientInfo;

long stripHeight = 16;
.
.
.

if (!ilQueryClientImage(image, &pClientInfo, 0))
return(context->error);

if (!ilFeedFromImage(pipe, (ilObject)image, pClientInfo->height,

stripHeight, TRUE, 0)) return(context->error);

RETURN VALUE

Upon successful completion, ilFeedFromImage() returns TRUE. 

ERRORS

If the call fails, context->error receives a non-zero error code. 

AUTHOR

ilFeedFromImage() was developed by HP. 

SEE ALSO

ilAddPipeElement(3X), ilFeedPipe(3X), ilerror(3X). 

Using the Image Developer’s Kit.

Hewlett-Packard Company  —  Image Library: February, 1995