diff options
Diffstat (limited to 'demos/python/examples.py')
| -rwxr-xr-x | demos/python/examples.py | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/demos/python/examples.py b/demos/python/examples.py new file mode 100755 index 00000000..d5c8b6ad --- /dev/null +++ b/demos/python/examples.py @@ -0,0 +1,171 @@ +#!/usr/bin/env python3 +# -*- coding: utf-8 -*- +""" +Created on Tue Jul 21 10:05:07 2020 +Example use of gsapi for various tasks. + +@author: Michael Vrhel +""" + +try: + import gsapi +except Exception: + print('Failure to import gsapi. Check shared library path') + raise + +import os + +ghostpdl_root = os.path.abspath('%s/../../..' % __file__) +print('ghostpdl_root=%s' % ghostpdl_root) + +def run_gpdl(params, path): + instance = gsapi.gsapi_new_instance(0) + gsapi.gsapi_set_arg_encoding(instance, gsapi.GS_ARG_ENCODING_UTF8) + gsapi.gsapi_add_control_path(instance, gsapi.GS_PERMIT_FILE_READING, path) + gsapi.gsapi_init_with_args(instance, params) + end_gpdl(instance) + +def init_gpdl(params): + instance = gsapi.gsapi_new_instance(0) + gsapi.gsapi_set_arg_encoding(instance, gsapi.GS_ARG_ENCODING_UTF8) + gsapi.gsapi_init_with_args(instance, params) + return instance + +def run_file(instance, filename): + exitcode = gsapi.gsapi_run_file(instance, filename, None) + return exitcode + +def end_gpdl(instance): + gsapi.gsapi_exit(instance) + gsapi.gsapi_delete_instance(instance) + +# run multiple files through same instance +def multiple_files(): + + out_filename = 'multi_file_output_%d.png' + + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=pngalpha', + '-r72', '-o', out_filename] + instance = init_gpdl(params) + run_file(instance, '%s/examples/tiger.eps' % ghostpdl_root) + run_file(instance, '%s/examples/snowflak.ps' % ghostpdl_root) + run_file(instance, '%s/examples/annots.pdf' % ghostpdl_root) + + end_gpdl(instance) + +# Extract text from source file +def extract_text(): + + in_filename = '%s/examples/alphabet.ps' % ghostpdl_root + out_filename = 'alphabet.txt' + print('Extracting text from %s to %s' % (in_filename, out_filename)) + + params =['gs', '-dNOPAUSE', '-dBATCH','-sDEVICE=txtwrite', + '-dTextFormat=3','-o', out_filename, '-f', in_filename] + run_gpdl(params, in_filename) + +# Perform different color conversions on text, graphic, and image content +# through the use of different destination ICC profiles +def object_dependent_color_conversion(): + + in_filename = '%s/examples/text_graph_image_cmyk_rgb.pdf' % ghostpdl_root + out_filename = 'rendered_profile.tif' + image_icc = '%s/toolbin/color/icc_creator/effects/cyan_output.icc' % ghostpdl_root + graphic_icc = '%s/toolbin/color/icc_creator/effects/magenta_output.icc' % ghostpdl_root + text_icc = '%s/toolbin/color/icc_creator/effects/yellow_output.icc' % ghostpdl_root + print('Object dependent color conversion on %s to %s' % (in_filename, out_filename)) + + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=tiff32nc', + '-r72','-sImageICCProfile=' + image_icc, + '-sTextICCProfile=' + text_icc, + '-sGraphicICCProfile=' + graphic_icc, + '-o', out_filename, '-f', in_filename] + + # Include ICC profile location to readable path + run_gpdl(params, '../../toolbin/color/icc_creator/effects/') + +# Perform different color conversions on text, graphic, and image content +# through the use of different rendering intents +def object_dependent_rendering_intent(): + + in_filename = '%s/examples/text_graph_image_cmyk_rgb.pdf' % ghostpdl_root + out_filename = 'rendered_intent.tif' + output_icc_profile = '%s/toolbin/color/src_color/cmyk_des_renderintent.icc' % ghostpdl_root + print('Object dependent rendering intents on %s to %s' % (in_filename, out_filename)) + + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=tiff32nc', + '-r72', '-sOutputICCProfile=' + output_icc_profile, + '-sImageICCIntent=0', '-sTextICCIntent=1', + '-sGraphicICCIntent=2', '-o', out_filename, + '-f', in_filename] + + # Include ICC profile location to readable path + run_gpdl(params, '../../toolbin/color/src_color/') + +# Distill +def distill(): + + in_filename = '%s/examples/tiger.eps' % ghostpdl_root + out_filename = 'tiger.pdf' + print('Distilling %s to %s' % (in_filename, out_filename)) + + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=pdfwrite', + '-o', out_filename, '-f', in_filename] + run_gpdl(params, in_filename) + +# Transparency in Postscript +def trans_ps(): + + in_filename = '%s/examples/transparency_example.ps' % ghostpdl_root + out_filename = 'transparency.png' + print('Rendering Transparency PS file %s to %s' % (in_filename, out_filename)) + + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=pngalpha', + '-dALLOWPSTRANSPARENCY', '-o', out_filename, '-f', in_filename] + run_gpdl(params, in_filename) + +# Run string to feed chunks +def run_string(): + + f = None + size = 1024; + in_filename = '%s/examples/tiger.eps' % ghostpdl_root + out_filename = 'tiger_byte_fed.png' + params =['gs', '-dNOPAUSE', '-dBATCH', '-sDEVICE=pngalpha', + '-o', out_filename] + + instance = gsapi.gsapi_new_instance(0) + + gsapi.gsapi_set_arg_encoding(instance, gsapi.GS_ARG_ENCODING_UTF8) + gsapi.gsapi_init_with_args(instance, params) + + exitcode = gsapi.gsapi_run_string_begin(instance, 0) + + with open(in_filename,"rb") as f: + while True: + data = f.read(size) + if not data: + break + exitcode = gsapi.gsapi_run_string_continue(instance, data, 0) + + exitcode = gsapi.gsapi_run_string_end(instance, 0) + + end_gpdl(instance) + + +# Examples +print('***********Text extraction***********'); +extract_text() +print('***********Color conversion***********') +object_dependent_color_conversion() +print('***********Rendering intent***********') +object_dependent_rendering_intent() +print('***********Distillation***************') +distill() +print('***********Postscript with transparency********') +trans_ps() +print('***********Multiple files********') +multiple_files() +print('***********Run string********') +run_string() +wait = input("press enter to exit") |