#!/usr/bin/python """ Main class This module contains the abstract base class :py:class:`Escpos`. :author: `Manuel F Martinez `_ and others :organization: Bashlinux and `python-escpos `_ :copyright: Copyright (c) 2012 Bashlinux :license: GNU GPL v3 """ from __future__ import absolute_import from __future__ import division from __future__ import print_function from __future__ import unicode_literals import six from PIL import Image import qrcode import textwrap import binascii import operator from .constants import * from .exceptions import * from abc import ABCMeta, abstractmethod # abstract base class support class Escpos(object): """ ESC/POS Printer object This class is the abstract base class for an esc/pos-printer. The printer implementations are children of this class. """ __metaclass__ = ABCMeta device = None def __init__(self, columns=32): """ Initialize ESCPOS Printer :param columns: Text columns used by the printer. Defaults to 32.""" self.columns = columns @abstractmethod def _raw(self, msg): """ Sends raw data to the printer This function has to be individually implemented by the implementations. :param msg: message string to be sent to the printer :type msg: bytes """ pass @staticmethod def _check_image_size(size): """ Check and fix the size of the image to 32 bits :param size: size of the image :returns: tuple of image borders :rtype: (int, int) """ if size % 32 == 0: return 0, 0 else: image_border = 32 - (size % 32) if (image_border % 2) == 0: return image_border // 2, image_border // 2 else: return image_border // 2, (image_border // 2) + 1 def _print_image(self, line, size): """ Print formatted image :param line: :param size: """ i = 0 cont = 0 pbuffer = b'' self._raw(S_RASTER_N) pbuffer = "%02X%02X%02X%02X" % (((size[0]//size[1])//8), 0, size[1] & 0xff, size[1] >> 8) self._raw(binascii.unhexlify(pbuffer)) pbuffer = "" while i < len(line): hex_string = int(line[i:i+8], 2) pbuffer += "%02X" % hex_string i += 8 cont += 1 if cont % 4 == 0: self._raw(binascii.unhexlify(pbuffer)) pbuffer = "" cont = 0 def _convert_image(self, im): """ Parse image and prepare it to a printable format :param im: image data :raises: :py:exc:`~escpos.exceptions.ImageSizeError` """ pixels = [] pix_line = "" im_left = "" im_right = "" switch = 0 img_size = [0, 0] if im.size[0] > 512: print ("WARNING: Image is wider than 512 and could be truncated at print time ") if im.size[1] > 0xffff: raise ImageSizeError() im_border = self._check_image_size(im.size[0]) for i in range(im_border[0]): im_left += "0" for i in range(im_border[1]): im_right += "0" for y in range(im.size[1]): img_size[1] += 1 pix_line += im_left img_size[0] += im_border[0] for x in range(im.size[0]): img_size[0] += 1 RGB = im.getpixel((x, y)) im_color = (RGB[0] + RGB[1] + RGB[2]) im_pattern = "1X0" pattern_len = len(im_pattern) switch = (switch - 1) * (-1) for x in range(pattern_len): if im_color <= (255 * 3 / pattern_len * (x+1)): if im_pattern[x] == "X": pix_line += "%d" % switch else: pix_line += im_pattern[x] break elif (255 * 3 / pattern_len * pattern_len) < im_color <= (255 * 3): pix_line += im_pattern[-1] break pix_line += im_right img_size[0] += im_border[1] self._print_image(pix_line, img_size) def image(self, path_img): """ Open and print an image file Prints an image. The image is automatically adjusted in size in order to print it. .. todo:: Seems to be broken. Write test that simply executes function with a dummy printer in order to check for bugs like these in the future. :param path_img: complete filename and path to image of type `jpg`, `gif`, `png` or `bmp` """ if not isinstance(path_img, Image.Image): im_open = Image.open(path_img) else: im_open = path_img # Remove the alpha channel on transparent images if im_open.mode == 'RGBA': im_open.load() im = Image.new("RGB", im_open.size, (255, 255, 255)) im.paste(im_open, mask=im_open.split()[3]) else: im = im_open.convert("RGB") # Convert the RGB image in printable image self._convert_image(im) def fullimage(self, img, max_height=860, width=512, histeq=True, bandsize=255): """ Resizes and prints an arbitrarily sized image .. todo:: Seems to be broken. Write test that simply executes function with a dummy printer in order to check for bugs like these in the future. """ if isinstance(img, Image.Image): im = img.convert("RGB") else: im = Image.open(img).convert("RGB") if histeq: # Histogram equaliztion h = im.histogram() lut = [] for b in range(0, len(h), 256): # step size step = reduce(operator.add, h[b:b+256]) / 255 # create equalization lookup table n = 0 for i in range(256): lut.append(n / step) n = n + h[i+b] im = im.point(lut) if width: ratio = float(width) / im.size[0] newheight = int(ratio * im.size[1]) # Resize the image im = im.resize((width, newheight), Image.ANTIALIAS) if max_height and im.size[1] > max_height: im = im.crop((0, 0, im.size[0], max_height)) # Divide into bands current = 0 while current < im.size[1]: self.image(im.crop((0, current, width or im.size[0], min(im.size[1], current + bandsize)))) current += bandsize def direct_image(self, image): """ Direct printing function for pictures This function is rather fragile and will fail when the Image object is not suited. :param image: PIL image object, containing a 1-bit picture """ mask = 0x80 i = 0 temp = 0 (width, height) = image.size self._raw(S_RASTER_N) headerX = int(width / 8) headerY = height buf = "%02X" % (headerX & 0xff) buf += "%02X" % ((headerX >> 8) & 0xff) buf += "%02X" % (headerY & 0xff) buf += "%02X" % ((headerY >> 8) & 0xff) #self._raw(binascii.unhexlify(buf)) for y in range(height): for x in range(width): value = image.getpixel((x, y)) value |= (value << 8) if value == 0: temp |= mask mask >>= 1 i += 1 if i == 8: buf += ("%02X" % temp) mask = 0x80 i = 0 temp = 0 self._raw(binascii.unhexlify(bytes(buf, "ascii"))) self._raw(b'\n') def qr(self, content, ec=QR_ECLEVEL_L, size=3, model=QR_MODEL_2, native=False): """ Print QR Code for the provided string :param content: The content of the code. Numeric data will be more efficiently compacted. :param ec: Error-correction level to use. One of QR_ECLEVEL_L (default), QR_ECLEVEL_M, QR_ECLEVEL_Q or QR_ECLEVEL_H. Higher error correction results in a less compact code. :param size: Pixel size to use. Must be 1-16 (default 3) :param model: QR code model to use. Must be one of QR_MODEL_1, QR_MODEL_2 (default) or QR_MICRO (not supported by all printers). :param native: True to render the code on the printer, False to render the code as an image and send it to the printer (Default) """ # Basic validation if not ec in [QR_ECLEVEL_L, QR_ECLEVEL_M, QR_ECLEVEL_H, QR_ECLEVEL_Q]: raise ValueError("Invalid error correction level") if not 1 <= size <= 16: raise ValueError("Invalid block size (must be 1-16)") if not model in [QR_MODEL_1, QR_MODEL_2, QR_MICRO]: raise ValueError("Invalid QR model (must be one of QR_MODEL_1, QR_MODEL_2, QR_MICRO)") if content == "": # Handle edge case by printing nothing. return if not native: # Map ESC/POS error correction levels to python 'qrcode' library constant and render to an image if model != QR_MODEL_2: raise ValueError("Invalid QR mocel for qrlib rendering (must be QR_MODEL_2)") python_qr_ec = { QR_ECLEVEL_H: qrcode.constants.ERROR_CORRECT_H, QR_ECLEVEL_L: qrcode.constants.ERROR_CORRECT_L, QR_ECLEVEL_M: qrcode.constants.ERROR_CORRECT_M, QR_ECLEVEL_Q: qrcode.constants.ERROR_CORRECT_Q } qr_code = qrcode.QRCode(version=None, box_size=size, border=1, error_correction=python_qr_ec[ec]) qr_code.add_data(content) qr_code.make(fit=True) qr_img = qr_code.make_image() im = qr_img._img.convert("RGB") # Convert the RGB image in printable image self._convert_image(im) return # Native 2D code printing cn = b'1' # Code type for QR code # Select model: 1, 2 or micro. self._send_2d_code_data(six.int2byte(65), cn, six.int2byte(48 + model) + six.int2byte(0)); # Set dot size. self._send_2d_code_data(six.int2byte(67), cn, six.int2byte(size)); # Set error correction level: L, M, Q, or H self._send_2d_code_data(six.int2byte(69), cn, six.int2byte(48 + ec)); # Send content & print self._send_2d_code_data(six.int2byte(80), cn, content.encode('utf-8'), b'0'); self._send_2d_code_data(six.int2byte(81), cn, b'', b'0'); def _send_2d_code_data(self, fn, cn, data, m=b''): """ Wrapper for GS ( k, to calculate and send correct data length. :param fn: Function to use. :param cn: Output code type. Affects available data. :param data: Data to send. :param m: Modifier/variant for function. Often '0' where used. """ if len(m) > 1 or len(cn) != 1 or len(fn) != 1: raise ValueError("cn and fn must be one byte each.") header = self._int_low_high(len(data) + len(m) + 2, 2); self._raw(GS + b'(k' + header + cn + fn + m + data) @staticmethod def _int_low_high(inp_number, out_bytes): """ Generate multiple bytes for a number: In lower and higher parts, or more parts as needed. :param inp_number: Input number :param out_bytes: The number of bytes to output (1 - 4). """ max_input = (256 << (out_bytes * 8) - 1); if not 1 <= out_bytes <= 4: raise ValueError("Can only output 1-4 byes") if not 0 <= inp_number <= max_input: raise ValueError("Number too large. Can only output up to {0} in {1} byes".format(max_input, out_bytes)) outp = b''; for _ in range(0, out_bytes): outp += six.int2byte(inp_number % 256) inp_number = inp_number // 256 return outp def charcode(self, code): """ Set Character Code Table Sends the control sequence from :py:mod:`escpos.constants` to the printer with :py:meth:`escpos.printer.'implementation'._raw()`. :param code: Name of CharCode :raises: :py:exc:`~escpos.exceptions.CharCodeError` """ if code.upper() == "USA": self._raw(CHARCODE_PC437) elif code.upper() == "JIS": self._raw(CHARCODE_JIS) elif code.upper() == "MULTILINGUAL": self._raw(CHARCODE_PC850) elif code.upper() == "PORTUGUESE": self._raw(CHARCODE_PC860) elif code.upper() == "CA_FRENCH": self._raw(CHARCODE_PC863) elif code.upper() == "NORDIC": self._raw(CHARCODE_PC865) elif code.upper() == "WEST_EUROPE": self._raw(CHARCODE_WEU) elif code.upper() == "GREEK": self._raw(CHARCODE_GREEK) elif code.upper() == "HEBREW": self._raw(CHARCODE_HEBREW) # elif code.upper() == "LATVIAN": # this is not listed in the constants # self._raw(CHARCODE_PC755) elif code.upper() == "WPC1252": self._raw(CHARCODE_PC1252) elif code.upper() == "CIRILLIC2": self._raw(CHARCODE_PC866) elif code.upper() == "LATIN2": self._raw(CHARCODE_PC852) elif code.upper() == "EURO": self._raw(CHARCODE_PC858) elif code.upper() == "THAI42": self._raw(CHARCODE_THAI42) elif code.upper() == "THAI11": self._raw(CHARCODE_THAI11) elif code.upper() == "THAI13": self._raw(CHARCODE_THAI13) elif code.upper() == "THAI14": self._raw(CHARCODE_THAI14) elif code.upper() == "THAI16": self._raw(CHARCODE_THAI16) elif code.upper() == "THAI17": self._raw(CHARCODE_THAI17) elif code.upper() == "THAI18": self._raw(CHARCODE_THAI18) else: raise CharCodeError() def barcode(self, code, bc, height=64, width=3, pos="BELOW", font="A", align_ct=True, function_type="A"): """ Print Barcode This method allows to print barcodes. The rendering of the barcode is done by the printer and therefore has to be supported by the unit. Currently you have to check manually whether your barcode text is correct. Uncorrect barcodes may lead to unexpected printer behaviour. There are two forms of the barcode function. Type A is default but has fewer barcodes, while type B has some more to choose from. .. todo:: Add a method to check barcode codes. Alternatively or as an addition write explanations about each barcode-type. Research whether the check digits can be computed autmatically. Use the parameters `height` and `width` for adjusting of the barcode size. Please take notice that the barcode will not be printed if it is outside of the printable area. (Which should be impossible with this method, so this information is probably more useful for debugging purposes.) .. todo:: On TM-T88II width from 1 to 6 is accepted. Try to acquire command reference and correct the code. .. todo:: Supplying pos does not have an effect for every barcode type. Check and document for which types this is true. If you do not want to center the barcode you can call the method with `align_ct=False`, which will disable automatic centering. Please note that when you use center alignment, then the alignment of text will be changed automatically to centered. You have to manually restore the alignment if necessary. .. todo:: If further barcode-types are needed they could be rendered transparently as an image. (This could also be of help if the printer does not support types that others do.) :param code: alphanumeric data to be printed as bar code :param bc: barcode format, possible values are for type A are: * UPC-A * UPC-E * EAN13 * EAN8 * CODE39 * ITF * NW7 Possible values for type B: * All types from function type A * CODE93 * CODE128 * GS1-128 * GS1 DataBar Omnidirectional * GS1 DataBar Truncated * GS1 DataBar Limited * GS1 DataBar Expanded If none is specified, the method raises :py:exc:`~escpos.exceptions.BarcodeTypeError`. :param height: barcode height, has to be between 1 and 255 *default*: 64 :type height: int :param width: barcode width, has to be between 2 and 6 *default*: 3 :type width: int :param pos: where to place the text relative to the barcode, *default*: BELOW * ABOVE * BELOW * BOTH * OFF :param font: select font (see ESC/POS-documentation, the device often has two fonts), *default*: A * A * B :param align_ct: If this parameter is True the barcode will be centered. Otherwise no alignment command will be issued. :type align_ct: bool :param function_type: Choose between ESCPOS function type A or B, depending on printer support and desired barcode. *default*: A :raises: :py:exc:`~escpos.exceptions.BarcodeSizeError`, :py:exc:`~escpos.exceptions.BarcodeTypeError`, :py:exc:`~escpos.exceptions.BarcodeCodeError` """ # Align Bar Code() if align_ct: self._raw(TXT_ALIGN_CT) # Height if 1 <= height <= 255: self._raw(BARCODE_HEIGHT + six.int2byte(height)) else: raise BarcodeSizeError("height = {height}".format(height=height)) # Width if 2 <= width <= 6: self._raw(BARCODE_WIDTH + six.int2byte(width)) else: raise BarcodeSizeError("width = {width}".format(width=width)) # Font if font.upper() == "B": self._raw(BARCODE_FONT_B) else: # DEFAULT FONT: A self._raw(BARCODE_FONT_A) # Position if pos.upper() == "OFF": self._raw(BARCODE_TXT_OFF) elif pos.upper() == "BOTH": self._raw(BARCODE_TXT_BTH) elif pos.upper() == "ABOVE": self._raw(BARCODE_TXT_ABV) else: # DEFAULT POSITION: BELOW self._raw(BARCODE_TXT_BLW) bc_types = BARCODE_TYPES[function_type.upper()] if bc.upper() not in bc_types.keys(): # TODO: Raise a better error, or fix the message of this error type raise BarcodeTypeError("Barcode type {bc} not valid for barcode function type {function_type}".format( bc=bc, function_type=function_type, )) self._raw(bc_types[bc.upper()]) if function_type.upper() == "B": self._raw(chr(len(code))) # Print Code if code: self._raw(code.encode()) else: raise BarcodeCodeError() if function_type.upper() == "A": self._raw("\x00") def text(self, txt): """ Print alpha-numeric text The text has to be encoded in the currently selected codepage. .. todo:: rework this in order to proberly handle encoding :param txt: text to be printed :raises: :py:exc:`~escpos.exceptions.TextError` """ if txt: self._raw(txt.encode()) else: # TODO: why is it problematic to print an empty string? raise TextError() def block_text(self, txt, columns=None): """ Text is printed wrapped to specified columns :param txt: text to be printed :param columns: amount of columns :return: None """ colCount = self.columns if columns is None else columns self.text(textwrap.fill(txt, colCount)) def set(self, align='left', font='a', text_type='normal', width=1, height=1, density=9, invert=False, smooth=False, flip=False): """ Set text properties by sending them to the printer :param align: horizontal position for text, possible values are: * CENTER * LEFT * RIGHT *default*: LEFT :param font: font type, possible values are A or B, *default*: A :param text_type: text type, possible values are: * B for bold * U for underlined * U2 for underlined, version 2 * BU for bold and underlined * BU2 for bold and underlined, version 2 * NORMAL for normal text *default*: NORMAL :param width: text width multiplier, decimal range 1-8, *default*: 1 :param height: text height multiplier, decimal range 1-8, *default*: 1 :param density: print density, value from 0-8, if something else is supplied the density remains unchanged :param invert: True enables white on black printing, *default*: False :param smooth: True enables text smoothing. Effective on 4x4 size text and larger, *default*: False :param flip: True enables upside-down printing, *default*: False :type invert: bool """ # Width if height == 2 and width == 2: self._raw(TXT_NORMAL) self._raw(TXT_4SQUARE) elif height == 2 and width == 1: self._raw(TXT_NORMAL) self._raw(TXT_2HEIGHT) elif width == 2 and height == 1: self._raw(TXT_NORMAL) self._raw(TXT_2WIDTH) elif width == 1 and height == 1: self._raw(TXT_NORMAL) elif 1 <= width <= 8 and 1 <= height <= 8 and isinstance(width, int) and isinstance(height, int): self._raw(TXT_SIZE + six.int2byte(TXT_WIDTH[width] + TXT_HEIGHT[height])) else: raise SetVariableError() # Upside down if flip == True: self._raw(TXT_FLIP_ON) else: self._raw(TXT_FLIP_OFF) # Smoothing if smooth == True: self._raw(TXT_SMOOTH_ON) else: self._raw(TXT_SMOOTH_OFF) # Type if text_type.upper() == "B": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL_OFF) elif text_type.upper() == "U": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL_ON) elif text_type.upper() == "U2": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL2_ON) elif text_type.upper() == "BU": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL_ON) elif text_type.upper() == "BU2": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL2_ON) elif text_type.upper == "NORMAL": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL_OFF) # Font if font.upper() == "B": self._raw(TXT_FONT_B) else: # DEFAULT FONT: A self._raw(TXT_FONT_A) # Align if align.upper() == "CENTER": self._raw(TXT_ALIGN_CT) elif align.upper() == "RIGHT": self._raw(TXT_ALIGN_RT) elif align.upper() == "LEFT": self._raw(TXT_ALIGN_LT) # Density if density == 0: self._raw(PD_N50) elif density == 1: self._raw(PD_N37) elif density == 2: self._raw(PD_N25) elif density == 3: self._raw(PD_N12) elif density == 4: self._raw(PD_0) elif density == 5: self._raw(PD_P12) elif density == 6: self._raw(PD_P25) elif density == 7: self._raw(PD_P37) elif density == 8: self._raw(PD_P50) else: # DEFAULT: DOES NOTHING pass # Invert Printing if invert: self._raw(TXT_INVERT_ON) else: self._raw(TXT_INVERT_OFF) def cut(self, mode=''): """ Cut paper. Without any arguments the paper will be cut completely. With 'mode=PART' a partial cut will be attempted. Note however, that not all models can do a partial cut. See the documentation of your printer for details. .. todo:: Check this function on TM-T88II. :param mode: set to 'PART' for a partial cut """ # Fix the size between last line and cut # TODO: handle this with a line feed self._raw(b"\n\n\n\n\n\n") if mode.upper() == "PART": self._raw(PAPER_PART_CUT) else: # DEFAULT MODE: FULL CUT self._raw(PAPER_FULL_CUT) def cashdraw(self, pin): """ Send pulse to kick the cash drawer Kick cash drawer on pin 2 or pin 5 according to parameter. :param pin: pin number, 2 or 5 :raises: :py:exc:`~escpos.exceptions.CashDrawerError` """ if pin == 2: self._raw(CD_KICK_2) elif pin == 5: self._raw(CD_KICK_5) else: raise CashDrawerError() def hw(self, hw): """ Hardware operations :param hw: hardware action, may be: * INIT * SELECT * RESET """ if hw.upper() == "INIT": self._raw(HW_INIT) elif hw.upper() == "SELECT": self._raw(HW_SELECT) elif hw.upper() == "RESET": self._raw(HW_RESET) else: # DEFAULT: DOES NOTHING pass def control(self, ctl, pos=4): """ Feed control sequences :param ctl: string for the following control sequences: * LF *for Line Feed* * FF *for Form Feed* * CR *for Carriage Return* * HT *for Horizontal Tab* * VT *for Vertical Tab* :param pos: integer between 1 and 16, controls the horizontal tab position :raises: :py:exc:`~escpos.exceptions.TabPosError` """ # Set tab positions if pos < 1 or pos > 16: raise TabPosError() else: self._raw(CTL_SET_HT + six.int2byte(pos)) # Set position if ctl.upper() == "LF": self._raw(CTL_LF) elif ctl.upper() == "FF": self._raw(CTL_FF) elif ctl.upper() == "CR": self._raw(CTL_CR) elif ctl.upper() == "HT": self._raw(CTL_HT) elif ctl.upper() == "VT": self._raw(CTL_VT) def panel_buttons(self, enable=True): """ Controls the panel buttons on the printer (e.g. FEED) When enable is set to False the panel buttons on the printer will be disabled. Calling the method with enable=True or without argument will enable the panel buttons. If panel buttons are enabled, the function of the panel button, such as feeding, will be executed upon pressing the button. If the panel buttons are disabled, pressing them will not have any effect. This command is effective until the printer is initialized, reset or power-cycled. The default is enabled panel buttons. Some panel buttons will always work, especially when printer is opened. See for more information the manual of your printer and the escpos-command-reference. :param enable: controls the panel buttons :rtype: None """ if enable: self._raw(PANEL_BUTTON_ON) else: self._raw(PANEL_BUTTON_OFF)