#! /usr/bin/env python

"""Test script for the imageop module.  This has the side

   effect of partially testing the imgfile module as well.

   Roger E. Masse

"""

from test.test_support import verbose, unlink

import imageop, uu, os

import warnings

warnings.filterwarnings("ignore",

                        "the rgbimg module is deprecated",

                        DeprecationWarning,

                        ".*test_imageop")

def main(use_rgbimg=1):

    # Create binary test files

    uu.decode(get_qualified_path('testrgb'+os.extsep+'uue'), 'test'+os.extsep+'rgb')

    if use_rgbimg:

        image, width, height = getrgbimage('test'+os.extsep+'rgb')

    else:

        image, width, height = getimage('test'+os.extsep+'rgb')

    # Return the selected part of image, which should by width by height

    # in size and consist of pixels of psize bytes.

    if verbose:

        print 'crop'

    newimage = imageop.crop (image, 4, width, height, 0, 0, 1, 1)

    # Return image scaled to size newwidth by newheight. No interpolation

    # is done, scaling is done by simple-minded pixel duplication or removal.

    # Therefore, computer-generated images or dithered images will

    # not look nice after scaling.

    if verbose:

        print 'scale'

    scaleimage = imageop.scale(image, 4, width, height, 1, 1)

    # Run a vertical low-pass filter over an image. It does so by computing

    # each destination pixel as the average of two vertically-aligned source

    # pixels. The main use of this routine is to forestall excessive flicker

    # if the image two vertically-aligned source pixels,  hence the name.

    if verbose:

        print 'tovideo'

    videoimage = imageop.tovideo (image, 4, width, height)

    # Convert an rgb image to an 8 bit rgb

    if verbose:

        print 'rgb2rgb8'

    greyimage = imageop.rgb2rgb8(image, width, height)

    # Convert an 8 bit rgb image to a 24 bit rgb image

    if verbose:

        print 'rgb82rgb'

    image = imageop.rgb82rgb(greyimage, width, height)

    # Convert an rgb image to an 8 bit greyscale image

    if verbose:

        print 'rgb2grey'

    greyimage = imageop.rgb2grey(image, width, height)

    # Convert an 8 bit greyscale image to a 24 bit rgb image

    if verbose:

        print 'grey2rgb'

    image = imageop.grey2rgb(greyimage, width, height)

    # Convert a 8-bit deep greyscale image to a 1-bit deep image by

    # thresholding all the pixels. The resulting image is tightly packed

    # and is probably only useful as an argument to mono2grey.

    if verbose:

        print 'grey2mono'

    monoimage = imageop.grey2mono (greyimage, width, height, 0)

    # monoimage, width, height = getimage('monotest.rgb')

    # Convert a 1-bit monochrome image to an 8 bit greyscale or color image.

    # All pixels that are zero-valued on input get value p0 on output and

    # all one-value input pixels get value p1 on output. To convert a

    # monochrome  black-and-white image to greyscale pass the values 0 and

    # 255 respectively.

    if verbose:

        print 'mono2grey'

    greyimage = imageop.mono2grey (monoimage, width, height, 0, 255)

    # Convert an 8-bit greyscale image to a 1-bit monochrome image using a

    # (simple-minded) dithering algorithm.

    if verbose:

        print 'dither2mono'

    monoimage = imageop.dither2mono (greyimage, width, height)

    # Convert an 8-bit greyscale image to a 4-bit greyscale image without

    # dithering.

    if verbose:

        print 'grey2grey4'

    grey4image = imageop.grey2grey4 (greyimage, width, height)

    # Convert an 8-bit greyscale image to a 2-bit greyscale image without

    # dithering.

    if verbose:

        print 'grey2grey2'

    grey2image = imageop.grey2grey2 (greyimage, width, height)

    # Convert an 8-bit greyscale image to a 2-bit greyscale image with

    # dithering. As for dither2mono, the dithering algorithm is currently

    # very simple.

    if verbose:

        print 'dither2grey2'

    grey2image = imageop.dither2grey2 (greyimage, width, height)

    # Convert a 4-bit greyscale image to an 8-bit greyscale image.

    if verbose:

        print 'grey42grey'

    greyimage = imageop.grey42grey (grey4image, width, height)

    # Convert a 2-bit greyscale image to an 8-bit greyscale image.

    if verbose:

        print 'grey22grey'

    image = imageop.grey22grey (grey2image, width, height)

    # Cleanup

    unlink('test'+os.extsep+'rgb')

def getrgbimage(name):

    """return a tuple consisting of image (in 'imgfile' format but

    using rgbimg instead) width and height"""

    import rgbimg

    try:

        sizes = rgbimg.sizeofimage(name)

    except rgbimg.error:

        name = get_qualified_path(name)

        sizes = rgbimg.sizeofimage(name)

    if verbose:

        print 'rgbimg opening test image: %s, sizes: %s' % (name, str(sizes))

    image = rgbimg.longimagedata(name)

    return (image, sizes[0], sizes[1])

def getimage(name):

    """return a tuple consisting of

       image (in 'imgfile' format) width and height

    """

    import imgfile

    try:

        sizes = imgfile.getsizes(name)

    except imgfile.error:

        name = get_qualified_path(name)

        sizes = imgfile.getsizes(name)

    if verbose:

        print 'imgfile opening test image: %s, sizes: %s' % (name, str(sizes))

    image = imgfile.read(name)

    return (image, sizes[0], sizes[1])

def get_qualified_path(name):

    """ return a more qualified path to name"""

    import sys

    import os

    path = sys.path

    try:

        path = [os.path.dirname(__file__)] + path

    except NameError:

        pass

    for dir in path:

        fullname = os.path.join(dir, name)

        if os.path.exists(fullname):

            return fullname

    return name

# rgbimg (unlike imgfile) is portable to platforms other than SGI.

# So we prefer to use it.

main(use_rgbimg=1)