#!/usr/bin/env python # -*- coding: utf-8 -*- """ This implementation of EventListener renders a PDF to an SVG image """ import base64 import io import typing import xml.etree.ElementTree from decimal import Decimal from PIL import Image as PILImageModule from borb.pdf.canvas.canvas import Canvas from borb.pdf.canvas.canvas_stream_processor import CanvasStreamProcessor from borb.pdf.canvas.color.color import Color from borb.pdf.canvas.event.begin_page_event import BeginPageEvent from borb.pdf.canvas.event.chunk_of_text_render_event import ChunkOfTextRenderEvent from borb.pdf.canvas.event.end_page_event import EndPageEvent from borb.pdf.canvas.event.event_listener import Event from borb.pdf.canvas.event.event_listener import EventListener from borb.pdf.canvas.event.image_render_event import ImageRenderEvent from borb.pdf.document.document import Document from borb.pdf.page.page import Page from borb.pdf.page.page_size import PageSize class PDFToSVG(EventListener): """ This implementation of EventListener renders a PDF to an SVG image """ # # CONSTRUCTOR # def __init__( self, default_page_width: Decimal = Decimal(PageSize.A4_PORTRAIT.value[0]), default_page_height: Decimal = Decimal(PageSize.A4_PORTRAIT.value[1]), ): self._default_page_width = default_page_width self._default_page_height = default_page_height self._page: typing.Optional[Page] = None self._page_nr = Decimal(-1) self._svg_per_page: typing.Dict[int, xml.etree.ElementTree.Element] = {} # # PRIVATE # def _begin_page( self, page_nr: Decimal, page_width: Decimal, page_height: Decimal ) -> None: # init svg image xml.etree.ElementTree.register_namespace("", "http://www.w3.org/2000/svg") svg_element = xml.etree.ElementTree.Element("svg") svg_element.set("xmlns:xlink", "http://www.w3.org/1999/xlink") svg_element.set("viewbox", "0 0 %d %d" % (page_width, page_height)) # white background rct_element = xml.etree.ElementTree.Element("rect") rct_element.set("width", str(page_width)) rct_element.set("height", str(page_height)) rct_element.set("style", "fill:rgb(255, 255, 255);") svg_element.append(rct_element) self._svg_per_page[int(page_nr)] = svg_element # type: ignore [assignment] def _event_occurred(self, event: Event) -> None: # BeginPageEvent if isinstance(event, BeginPageEvent): self._page_nr += Decimal(1) self._page = event.get_page() self._begin_page( self._page_nr, self._page.get_page_info().get_width() or self._default_page_width, self._page.get_page_info().get_height() or self._default_page_height, ) # ImageRenderEvent if isinstance(event, ImageRenderEvent): assert self._page is not None self._render_image( self._page_nr, self._page.get_page_info().get_width() or self._default_page_width, self._page.get_page_info().get_height() or self._default_page_height, event.get_x(), event.get_y(), event.get_width(), event.get_height(), event.get_image(), ) # ChunkOfTextRenderEvent if isinstance(event, ChunkOfTextRenderEvent): assert self._page is not None font_name_as_str = "Helvetica" if event.get_font().get_font_name(): font_name_as_str = str(event.get_font().get_font_name()) self._render_text( self._page_nr, self._page.get_page_info().get_width() or self._default_page_width, self._page.get_page_info().get_height() or self._default_page_height, event.get_baseline().get_x(), event.get_baseline().get_y(), event.get_font_color(), event.get_font_size(), font_name_as_str.replace("#20", " ") .replace(",Bold", "") .replace(",bold", "") .replace("Bold", "") .replace("bold", "") .replace(",Italic", "") .replace(",italic", "") .replace("Italic", "") .replace("italic", ""), "BOLD" in font_name_as_str.upper(), "ITALIC" in font_name_as_str.upper(), event.get_text(), ) def _render_image( self, page_nr: Decimal, page_width: Decimal, page_height: Decimal, x: Decimal, y: Decimal, image_width: Decimal, image_height: Decimal, image: PILImageModule.Image, # type: ignore[valid-type] ): pass # base64 image with io.BytesIO() as output: image.convert("RGB").save(output, format="JPEG") # type: ignore[attr-defined] base64_image = "data:image/png;base64," + base64.b64encode( output.getvalue() ).decode("utf-8") image_element = xml.etree.ElementTree.Element("image") image_element.set("width", str(int(image_width))) image_element.set("height", str(int(image_height))) image_element.set("xlink:href", base64_image) # position image_element.set("x", str(int(x))) image_element.set("y", str(int(page_height - y - image_height))) # append assert self._svg_per_page[int(page_nr)] is not None self._svg_per_page[int(page_nr)].append(image_element) def _render_text( self, page_nr: Decimal, page_width: Decimal, page_height: Decimal, x: Decimal, y: Decimal, font_color: Color, font_size: Decimal, font_name: str, bold: bool, italic: bool, text: str, ): if len(text.strip()) == 0: return text_element = xml.etree.ElementTree.Element("text") # bold if bold: text_element.set("_font-weight", "bold") # italic if italic: text_element.set("_font-style", "italic") # font_color, font_size, preserve space font_color_rgb = font_color.to_rgb() text_element.set( "style", "fill:rgb(%d, %d, %d); _font-size:%d px; white-space: pre;" % ( font_color_rgb.red, font_color_rgb.green, font_color_rgb.blue, int(font_size), ), ) text_element.set("xml:space", "preserve") # set font-family text_element.set("_font-family", font_name) # text text_element.text = text # position text_element.set("x", str(int(x))) text_element.set("y", str(int(page_height - y))) # append assert self._svg_per_page[int(page_nr)] is not None self._svg_per_page[int(page_nr)].append(text_element) # # PUBLIC # @staticmethod def convert_pdf_to_svg( pdf: Document, ) -> typing.Dict[int, xml.etree.ElementTree.Element]: """ This function converts a PDF to an SVG xml.etree.ElementTree.Element """ image_of_each_page: typing.Dict[int, xml.etree.ElementTree.Element] = {} number_of_pages: int = int(pdf.get_document_info().get_number_of_pages() or 0) for page_nr in range(0, number_of_pages): # get Page object page: Page = pdf.get_page(page_nr) page_source: io.BytesIO = io.BytesIO(page["Contents"]["DecodedBytes"]) # register EventListener cse: "PDFToSVG" = PDFToSVG() # process Page cse._event_occurred(BeginPageEvent(page)) CanvasStreamProcessor(page, Canvas(), []).read(page_source, [cse]) cse._event_occurred(EndPageEvent(page)) # set in page image_of_each_page[page_nr] = cse.convert_to_svg()[0] # return return image_of_each_page def convert_to_svg(self) -> typing.Dict[int, xml.etree.ElementTree.Element]: """ This function returns the xml.etree.ElementTree.Element for a given page_nr """ return self._svg_per_page