Python PIL.ImageFilter.MinFilter() Examples

def test_sanity(self):

        def filter(filter):
            for mode in ["L", "RGB", "CMYK"]:
                im = hopper(mode)
                out = im.filter(filter)
                self.assertEqual(out.mode, im.mode)
                self.assertEqual(out.size, im.size)

        filter(ImageFilter.BLUR)
        filter(ImageFilter.CONTOUR)
        filter(ImageFilter.DETAIL)
        filter(ImageFilter.EDGE_ENHANCE)
        filter(ImageFilter.EDGE_ENHANCE_MORE)
        filter(ImageFilter.EMBOSS)
        filter(ImageFilter.FIND_EDGES)
        filter(ImageFilter.SMOOTH)
        filter(ImageFilter.SMOOTH_MORE)
        filter(ImageFilter.SHARPEN)
        filter(ImageFilter.MaxFilter)
        filter(ImageFilter.MedianFilter)
        filter(ImageFilter.MinFilter)
        filter(ImageFilter.ModeFilter)
        filter(ImageFilter.GaussianBlur)
        filter(ImageFilter.GaussianBlur(5))
        filter(ImageFilter.BoxBlur(5))
        filter(ImageFilter.UnsharpMask)
        filter(ImageFilter.UnsharpMask(10))

        self.assertRaises(TypeError, filter, "hello") 

def test_rankfilter(self):

        def rankfilter(mode):
            im = Image.new(mode, (3, 3), None)
            im.putdata(list(range(9)))
            # image is:
            #   0 1 2
            #   3 4 5
            #   6 7 8
            minimum = im.filter(ImageFilter.MinFilter).getpixel((1, 1))
            med = im.filter(ImageFilter.MedianFilter).getpixel((1, 1))
            maximum = im.filter(ImageFilter.MaxFilter).getpixel((1, 1))
            return minimum, med, maximum

        self.assertEqual(rankfilter("1"), (0, 4, 8))
        self.assertEqual(rankfilter("L"), (0, 4, 8))
        self.assertRaises(ValueError, rankfilter, "P")
        self.assertEqual(rankfilter("RGB"), ((0, 0, 0), (4, 0, 0), (8, 0, 0)))
        self.assertEqual(rankfilter("I"), (0, 4, 8))
        self.assertEqual(rankfilter("F"), (0.0, 4.0, 8.0)) 

def test_pillow_image_filter_filter():
    stim = ImageStim(join(IMAGE_DIR, 'thai_people.jpg'))
    with pytest.raises(ValueError):
        filt = PillowImageFilter()
    filt = PillowImageFilter('BLUR')
    blurred = filt.transform(stim)
    assert blurred is not None

    from PIL import ImageFilter
    filt2 = PillowImageFilter(ImageFilter.FIND_EDGES)
    edges = filt2.transform(stim)
    assert np.array_equal(edges.data[0, 0], [134, 85, 45])

    filt3 = PillowImageFilter(ImageFilter.MinFilter(3))
    min_img = filt3.transform(stim)
    assert np.array_equal(min_img.data[0, 0], [122, 74, 36])

    filt4 = PillowImageFilter('MinFilter')
    min_img = filt4.transform(stim)
    assert np.array_equal(min_img.data[0, 0], [122, 74, 36])

    filt5 = PillowImageFilter(ImageFilter.MaxFilter, size=3)
    med_img = filt5.transform(stim)
    assert np.array_equal(med_img.data[0, 0], [136, 86, 49]) 

def detect_gf_result(image_path):
    from PIL import ImageFilter, Image
    import pytesseract
    img = Image.open(image_path)
    for x in range(img.width):
        for y in range(img.height):
            if img.getpixel((x, y)) < (100, 100, 100):
                img.putpixel((x, y), (256, 256, 256))
    gray = img.convert('L')
    two = gray.point(lambda x: 0 if 68 < x < 90 else 256)
    min_res = two.filter(ImageFilter.MinFilter)
    med_res = min_res.filter(ImageFilter.MedianFilter)
    for _ in range(2):
        med_res = med_res.filter(ImageFilter.MedianFilter)
    res = pytesseract.image_to_string(med_res, config='-psm 6')
    return res.replace(' ', '') 

def detect_gf_result(image_path):
    from PIL import ImageFilter, Image

    img = Image.open(image_path)
    if hasattr(img, "width"):
        width, height = img.width, img.height
    else:
        width, height = img.size
    for x in range(width):
        for y in range(height):
            if img.getpixel((x, y)) < (100, 100, 100):
                img.putpixel((x, y), (256, 256, 256))
    gray = img.convert("L")
    two = gray.point(lambda p: 0 if 68 < p < 90 else 256)
    min_res = two.filter(ImageFilter.MinFilter)
    med_res = min_res.filter(ImageFilter.MedianFilter)
    for _ in range(2):
        med_res = med_res.filter(ImageFilter.MedianFilter)
    return invoke_tesseract_to_recognize(med_res) 

def vcode(self):

        # 获取校验码
        r = self._session.get('https://trade.gf.com.cn/yzm.jpgx')
        r.raise_for_status()

        # 通过内存保存图片，进行识别
        img_buffer = BytesIO(r.content)
        img = Image.open(img_buffer)
        if hasattr(img, "width"):
            width, height = img.width, img.height
        else:
            width, height = img.size
        for x in range(width):
            for y in range(height):
                if img.getpixel((x, y)) < (100, 100, 100):
                    img.putpixel((x, y), (256, 256, 256))

        gray = img.convert('L')
        two = gray.point(lambda x: 0 if 68 < x < 90 else 256)
        min_res = two.filter(ImageFilter.MinFilter)
        med_res = min_res.filter(ImageFilter.MedianFilter)
        for _ in range(1):
            med_res = med_res.filter(ImageFilter.MedianFilter)

        # 通过tesseract-ocr的工具进行校验码识别
        vcode = pytesseract.image_to_string(med_res)
        img.close()
        img_buffer.close()

        vcode = vcode.replace(' ', '')
        if self.code_rule.findall(vcode) != []:
            logger.debug('vcode is: %s' % vcode)
            return vcode
        else:
            raise VerifyCodeError('verify code error: %s' % vcode) 

def filter_footer(self, img):
        """Filter to remove the hight quality footer for an image."""
        # Some sites like MangaFox add an extra footer in the original
        # image.  This footer remove importan space in the Kindle, and
        # we need to remove it.
        #
        # The algorithm use as a leverage the normal noise present in
        # an scanned image, that is higher than the one in the footer.
        # This means that this filter will only work in medium quality
        # scanners, but possibly not in high quality ones.
        #
        # The process is like this:
        #
        #   1.- Binarize the image, moving the noise at the same level
        #       that the real information.
        #
        #   2.- Use a MinFilter of size 3 to a big mass of pixels that
        #       containg high frequency data.  That usually means
        #       pixels surrounded with blanks.
        #
        #   3.- Do a Gaussian filter to lower more the high frequency
        #       data, moving the mass close arround the pixel.  This
        #       will lower more the pixels surrounded with gaps.
        #
        #   4.- Discard the pixels with low mass.
        #
        _img = ImageOps.invert(img.convert(mode='L'))
        _img = _img.point(lambda x: x and 255)
        _img = _img.filter(ImageFilter.MinFilter(size=3))
        _img = _img.filter(ImageFilter.GaussianBlur(radius=5))
        _img = _img.point(lambda x: (x >= 48) and x)
        # If the image is white, we do not have bbox
        return img.crop(_img.getbbox()) if _img.getbbox() else img 

def downloader(self, url, counter, parser):
        """Method that downloads files"""

        # Check if we have the Download folder
        helper.createFolder(self.downloadfolder)

        imagepath = self.downloadfolder + "/" + str("{0:0=3d}".format(counter)) + ".png"
        tempdl = self.downloadfolder + "/" + str("{0:0=3d}".format(counter)) + ".tmp"

        # Download the image!
        f = open(tempdl, 'wb')
        f.write(requests.get(parser(url), headers={'referer': url}).content)
        f.close()

        # convert img to png
        imgtest = Image.open(tempdl)
        if imgtest.format != 'PNG':
            logging.debug("Image %s is not a PNG... convertig.", tempdl)
            imgtest.save(tempdl, "PNG")
        else:
            imgtest.close()

        # If everything is alright, write image to final name
        os.rename(tempdl, imagepath)


        # Cleanse image, remove footer
        #
        #   I have borrowed this code from the kmanga project.
        #   https://github.com/aplanas/kmanga/blob/master/mobi/mobi.py#L416
        #   Thanks a lot to Alberto Planas for coming up with it!
        #
        if self.origin == "mangafox.me" or self.origin == "mangafox.la" or self.origin == "fanfox.net":
            logging.debug("Cleaning Mangafox Footer")
            img = Image.open(imagepath)
            _img = ImageOps.invert(img.convert(mode='L'))
            _img = _img.point(lambda x: x and 255)
            _img = _img.filter(ImageFilter.MinFilter(size=3))
            _img = _img.filter(ImageFilter.GaussianBlur(radius=5))
            _img = _img.point(lambda x: (x >= 48) and x)

            cleaned = img.crop(_img.getbbox()) if _img.getbbox() else img
            cleaned.save(imagepath)