lyx_mirror/lib/scripts/legacy_lyxpreview2ppm.py
José Matos d06a034578 Python 3.13 removed the pipes module from the standard library
That module was a wrapper over the popen module and it was scheduled to
be removed in Python 3.11.

This code is also compatible with Python 2.
2024-08-25 10:14:18 +01:00

588 lines
22 KiB
Python

# file legacy_lyxpreview2ppm.py
# This file is part of LyX, the document processor.
# Licence details can be found in the file COPYING.
# author Angus Leeming
# Full author contact details are available in file CREDITS
# with much advice from members of the preview-latex project:
# David Kastrup, dak@gnu.org and
# Jan-Åke Larsson, jalar@mai.liu.se.
# and with much help testing the code under Windows from
# Paul A. Rubin, rubin@msu.edu.
# This script takes a LaTeX file and generates a collection of
# png or ppm image files, one per previewed snippet.
# Example usage:
# legacy_lyxpreview2bitmap.py 0lyxpreview.tex 128 ppm 000000 faf0e6
# This script takes five arguments:
# TEXFILE: the name of the .tex file to be converted.
# SCALEFACTOR: a scale factor, used to ascertain the resolution of the
# generated image which is then passed to gs.
# OUTPUTFORMAT: the format of the output bitmap image files.
# This particular script can produce only "ppm" format output.
# FG_COLOR: the foreground color as a hexadecimal string, eg '000000'.
# BG_COLOR: the background color as a hexadecimal string, eg 'faf0e6'.
# Decomposing TEXFILE's name as DIR/BASE.tex, this script will,
# if executed successfully, leave in DIR:
# * a (possibly large) number of image files with names
# like BASE[0-9]+.(ppm|png)
# * a file BASE.metrics, containing info needed by LyX to position
# the images correctly on the screen.
# The script uses several external programs and files:
# * python 2.4 or later (subprocess module);
# * A latex executable;
# * preview.sty;
# * dvips;
# * gs;
# * pdflatex (optional);
# * pnmcrop (optional).
# * pdftocairo (optional).
# * epstopdf (optional).
# preview.sty is part of the preview-latex project
# http://preview-latex.sourceforge.net/
# Alternatively, it can be obtained from
# CTAN/support/preview-latex/
# What does this script do?
# [legacy_conversion]
# 0) Process command-line arguments
# [legacy_conversion_step1]
# 1) Call latex to create a DVI file from LaTeX
# [legacy_conversion_step2]
# 2) Call dvips to create one PS file for each DVI page
# [legacy_conversion_step3]
# 3) If dvips fails look for PDF and call pdftocairo or gs to produce bitmaps
# 4) Otherwise call pdftocairo or gs on each PostScript file to produce bitmaps
# [legacy_conversion_pdflatex]
# 5) Keep track of pages on which gs failed and pass them to pdflatex
# 6) Call pdftocairo or gs on the PDF output from pdflatex to produce bitmaps
# 7) Extract and write to file (or return to lyxpreview2bitmap)
# metrics from both methods (standard and pdflatex)
# The script uses the old dvi->ps->png conversion route,
# which is good when using PSTricks, TikZ or other packages involving
# PostScript literals (steps 1, 2, 4).
# This script also generates bitmaps from PDF created by a call to
# lyxpreview2bitmap.py passing "pdflatex" to the CONVERTER parameter
# (step 3).
# Finally, there's also has a fallback method based on pdflatex, which
# is required in certain cases, if hyperref is active for instance,
# (step 5, 6).
# If possible, dvipng should be used, as it's much faster.
# If possible, the script will use pdftocairo instead of gs,
# as it's much faster and gives better results.
import glob, os, re, subprocess, sys, tempfile
from lyxpreview_tools import check_latex_log, copyfileobj, error, filter_pages,\
find_exe, find_exe_or_terminate, join_metrics_and_rename, latex_commands, \
latex_file_re, make_texcolor, pdflatex_commands, progress, \
run_command, run_latex, warning, write_metrics_info
def usage(prog_name):
return "Usage: %s <latex file> <dpi> ppm <fg color> <bg color>\n" \
"\twhere the colors are hexadecimal strings, eg 'faf0e6'" \
% prog_name
# Returns a list of tuples containing page number and ascent fraction
# extracted from dvipng output.
# Use write_metrics_info to create the .metrics file with this info
def legacy_extract_metrics_info(log_file):
log_re = re.compile(b"Preview: ([ST])")
data_re = re.compile(b"(-?[0-9]+) (-?[0-9]+) (-?[0-9]+) (-?[0-9]+)")
tp_ascent = 0.0
tp_descent = 0.0
success = 0
results = []
try:
for line in open(log_file, 'rb').readlines():
match = log_re.match(line)
if match == None:
continue
snippet = (match.group(1) == b'S')
success = 1
match = data_re.search(line)
if match == None:
error(f"Unexpected data in {log_file}\n{line}")
if snippet:
ascent = float(match.group(2))
descent = float(match.group(3))
frac = 0.5
if ascent == 0 and descent == 0:
# This is an empty image, forbid its display
frac = -1.0
elif ascent >= 0 or descent >= 0:
ascent = ascent + tp_ascent
descent = descent - tp_descent
if abs(ascent + descent) > 0.1:
frac = ascent / (ascent + descent)
# Sanity check
if frac < 0 or frac > 1:
frac = 0.5
results.append((int(match.group(1)), frac))
else:
tp_descent = float(match.group(2))
tp_ascent = float(match.group(4))
except:
# Unable to open the file, but do nothing here because
# the calling function will act on the value of 'success'.
warning(f'Warning in legacy_extract_metrics_info! Unable to open "{log_file}"')
warning(repr(sys.exc_info()[0]) + ',' + repr(sys.exc_info()[1]))
if success == 0:
error(f"Failed to extract metrics info from {log_file}")
return results
def extract_resolution(log_file, dpi):
fontsize_re = re.compile(b"Preview: Fontsize")
magnification_re = re.compile(b"Preview: Magnification")
extract_decimal_re = re.compile(br"([0-9\.]+)")
extract_integer_re = re.compile(b"([0-9]+)")
found_fontsize = 0
found_magnification = 0
# Default values
magnification = 1000.0
fontsize = 10.0
try:
for line in open(log_file, 'rb').readlines():
if found_fontsize and found_magnification:
break
if not found_fontsize:
match = fontsize_re.match(line)
if match != None:
match = extract_decimal_re.search(line)
if match == None:
error(f"Unable to parse: {line}")
fontsize = float(match.group(1))
found_fontsize = 1
continue
if not found_magnification:
match = magnification_re.match(line)
if match != None:
match = extract_integer_re.search(line)
if match == None:
error("Unable to parse: %s" % line)
magnification = float(match.group(1))
found_magnification = 1
continue
except:
warning('Warning in extract_resolution! Unable to open "%s"' % log_file)
warning(repr(sys.exc_info()[0]) + ',' + repr(sys.exc_info()[1]))
# This is safe because both fontsize and magnification have
# non-zero default values.
return dpi * (10.0 / fontsize) * (1000.0 / magnification)
def legacy_latex_file(latex_file, fg_color, bg_color):
use_polyglossia_re = re.compile(b"\\s*\\\\usepackage{polyglossia}")
use_preview_re = re.compile(b"\\s*\\\\usepackage\\[([^]]+)\\]{preview}")
fg_color_gr = make_texcolor(fg_color, True)
bg_color_gr = make_texcolor(bg_color, True)
tmp = tempfile.TemporaryFile()
success = 0
try:
f = open(latex_file, 'rb')
except:
# Unable to open the file, but do nothing here because
# the calling function will act on the value of 'success'.
warning('Warning in legacy_latex_file! Unable to open "%s"' % latex_file)
warning(repr(sys.exc_info()[0]) + ',' + repr(sys.exc_info()[1]))
polyglossia = False
for line in f.readlines():
if success:
tmp.write(line)
continue
match = use_preview_re.match(line)
polymatch = use_polyglossia_re.match(line)
# Package order:
# * if polyglossia is used, we need to load color before that
# (also, we do not have to load lmodern)
# * else, color should be loaded before preview
if match == None:
if polymatch == None:
tmp.write(line)
continue
else:
tmp.write(b"""
\\usepackage{color}
\\definecolor{lyxfg}{rgb}{%s}
\\definecolor{lyxbg}{rgb}{%s}
\\pagecolor{lyxbg}
\\usepackage{polyglossia}
""" % (fg_color_gr, bg_color_gr))
polyglossia = True
continue
success = 1
# Preview options: add the options lyx and tightpage
previewopts = match.group(1)
if not polyglossia:
tmp.write(b"""
\\usepackage{color}
\\definecolor{lyxfg}{rgb}{%s}
\\definecolor{lyxbg}{rgb}{%s}
\\pagecolor{lyxbg}
\\makeatletter
\\def\\@tempa{cmr}
\\ifx\\f@family\\@tempa
\\IfFileExists{lmodern.sty}{\\usepackage{lmodern}}{\\usepackage{ae,aecompl}}
\\fi
""" % (fg_color_gr, bg_color_gr))
tmp.write(b"""
\\usepackage[%s,tightpage]{preview}
\\makeatletter
\\g@addto@macro\\preview{\\leavevmode\\begingroup\\color{lyxbg}\\special{background \\current@color}\\special{ps::clippath fill}\\color{lyxfg}}
\\g@addto@macro\\endpreview{\\endgroup}
\\let\\pr@set@pagerightoffset\\@empty
\\ifx\\pagerightoffset\\@undefined\\else
\\def\\pr@set@pagerightoffset{\\ifnum\\pagedirection=1
\\pagerightoffset=-1in
\\advance\\pagerightoffset-\\pr@bb@i
\\advance\\pagerightoffset\\pr@bb@iii
\\fi
}
\\fi
\\g@addto@macro\\pr@ship@end{\\pr@set@pagerightoffset}
\\makeatother
""" % previewopts)
if success:
copyfileobj(tmp, open(latex_file,"wb"), 1)
return success
def crop_files(pnmcrop, basename):
for file in glob.glob("%s*.ppm" % basename):
tmp = tempfile.TemporaryFile()
conv_call = f'{pnmcrop} -left -right -- {file}'
conv_status = subprocess.run(conv_call, stdout=tmp)
if conv_status:
continue
copyfileobj(tmp, open(file, "wb"), 1)
def legacy_conversion(argv, skipMetrics = False):
# Parse and manipulate the command line arguments.
if len(argv) == 7:
latex = [argv[6]]
elif len(argv) != 6:
error(usage(argv[0]))
else:
latex = None
dir, latex_file = os.path.split(argv[1])
if len(dir) != 0:
os.chdir(dir)
dpi = int(argv[2])
output_format = argv[3]
fg_color = argv[4]
bg_color = argv[5]
# External programs used by the script.
latex = find_exe_or_terminate(latex or latex_commands)
pdf_output = latex in pdflatex_commands
return legacy_conversion_step1(latex_file, dpi, output_format, fg_color,
bg_color, latex, pdf_output, skipMetrics)
# Add color info to the latex file, since ghostscript doesn't
# have the option to set foreground and background colors on
# the command line. Run the resulting file through latex.
def legacy_conversion_step1(latex_file, dpi, output_format, fg_color, bg_color,
latex, pdf_output = False, skipMetrics = False):
# Move color information, lyx and tightpage options into the latex file.
if not legacy_latex_file(latex_file, fg_color, bg_color):
error("""Unable to move the color information, and the lyx and tightpage
options of preview-latex, into the latex file""")
# Compile the latex file.
latex_status, latex_stdout = run_latex(latex, latex_file)
if latex_status:
progress("Will try to recover from %s failure" % latex)
if pdf_output:
return legacy_conversion_step3(latex_file, dpi, output_format, True, skipMetrics)
else:
return legacy_conversion_step2(latex_file, dpi, output_format, skipMetrics)
# Creates a new LaTeX file from the original with pages specified in
# failed_pages, pass it through pdflatex and updates the metrics
# from the standard legacy route
def legacy_conversion_pdflatex(latex_file, failed_pages, legacy_metrics,
use_pdftocairo, conv, gs_device, gs_ext, alpha, resolution, output_format):
error_count = 0
# Search for pdflatex executable
pdflatex = find_exe(["pdflatex"])
if pdflatex == None:
warning("Can't find pdflatex. Some pages failed with all the possible routes.")
failed_pages = []
else:
# Create a new LaTeX file from the original but only with failed pages
pdf_latex_file = latex_file_re.sub("_pdflatex.tex", latex_file)
filter_pages(latex_file, pdf_latex_file, failed_pages)
# pdflatex call
error_pages = []
pdflatex_status, pdflatex_stdout = run_latex(pdflatex, pdf_latex_file)
if pdflatex_status:
error_pages = check_latex_log(latex_file_re.sub(".log", pdf_latex_file))
pdf_file = latex_file_re.sub(".pdf", pdf_latex_file)
latex_file_root = latex_file_re.sub("", pdf_latex_file)
# Converter call to produce bitmaps
if use_pdftocairo:
conv_call = '%s -png -transp -r %d "%s" "%s"' \
% (conv, resolution, pdf_file, latex_file_root)
conv_status, conv_stdout = run_command(conv_call)
if not conv_status:
seqnum_re = re.compile("-([0-9]+)")
for name in glob.glob("%s-*.png" % latex_file_root):
match = seqnum_re.search(name)
if match != None:
new_name = seqnum_re.sub(str(int(match.group(1))), name)
os.rename(name, new_name)
else:
conv_call = '%s -dNOPAUSE -dBATCH -dSAFER -sDEVICE=%s ' \
'-sOutputFile="%s%%d.%s" ' \
'-dGraphicsAlphaBit=%d -dTextAlphaBits=%d ' \
'-r%f "%s"' \
% (conv, gs_device, latex_file_root, \
gs_ext, alpha, alpha, resolution, pdf_file)
conv_status, conv_stdout = run_command(conv_call)
if conv_status:
# Give up!
warning("Some pages failed with all the possible routes")
failed_pages = []
else:
# We've done it!
pdf_log_file = latex_file_re.sub(".log", pdf_latex_file)
pdf_metrics = legacy_extract_metrics_info(pdf_log_file)
# Invalidate metrics for pages that produced errors
if len(error_pages) > 0:
for index in error_pages:
pdf_metrics.pop(index - 1)
pdf_metrics.insert(index - 1, (index, -1.0))
error_count += 1
original_bitmap = latex_file_re.sub("%d." + output_format, pdf_latex_file)
destination_bitmap = latex_file_re.sub("%d." + output_format, latex_file)
# Join the metrics with the those from dvips and rename the bitmap images
join_metrics_and_rename(legacy_metrics, pdf_metrics, failed_pages,
original_bitmap, destination_bitmap)
return error_count
# The file has been processed through latex and we expect dvi output.
# Run dvips, taking note whether it was successful.
def legacy_conversion_step2(latex_file, dpi, output_format, skipMetrics = False):
# External programs used by the script.
dvips = find_exe_or_terminate(["dvips"])
# Run the dvi file through dvips.
dvi_file = latex_file_re.sub(".dvi", latex_file)
ps_file = latex_file_re.sub(".ps", latex_file)
dvips_call = f'{dvips} -i -o "{ps_file}" "{dvi_file}"'
dvips_failed = False
dvips_status, dvips_stdout = run_command(dvips_call)
if dvips_status:
warning(f'Failed: {os.path.basename(dvips)} {dvi_file} ... looking for PDF')
dvips_failed = True
return legacy_conversion_step3(latex_file, dpi, output_format, dvips_failed, skipMetrics)
# Either latex and dvips have been run and we have a ps file, or
# pdflatex has been run and we have a pdf file. Proceed with pdftocairo or gs.
def legacy_conversion_step3(latex_file, dpi, output_format, dvips_failed, skipMetrics = False):
# External programs used by the script.
gs = find_exe_or_terminate(["gswin32c", "gswin64c", "gs"])
pnmcrop = find_exe(["pnmcrop"])
pdftocairo = find_exe(["pdftocairo"])
epstopdf = find_exe(["epstopdf"])
use_pdftocairo = pdftocairo != None and output_format == "png"
if use_pdftocairo and os.name == 'nt':
# On Windows, check for png support (see #10718)
conv_status, conv_stdout = run_command("%s --help" % pdftocairo)
use_pdftocairo = '-png' in conv_stdout
if use_pdftocairo:
conv = pdftocairo
else:
conv = gs
# Files to process
pdf_file = latex_file_re.sub(".pdf", latex_file)
ps_file = latex_file_re.sub(".ps", latex_file)
# The latex file name without extension
latex_file_root = latex_file_re.sub("", latex_file)
# Extract resolution data for the converter from the log file.
log_file = latex_file_re.sub(".log", latex_file)
resolution = extract_resolution(log_file, dpi)
# Check whether some pages produced errors
error_pages = check_latex_log(log_file)
# Older versions of gs have problems with a large degree of
# anti-aliasing at high resolutions
alpha = 4
if resolution > 150:
alpha = 2
gs_device = "png16m"
gs_ext = "png"
if output_format == "ppm":
gs_device = "pnmraw"
gs_ext = "ppm"
# Extract the metrics from the log file
legacy_metrics = legacy_extract_metrics_info(log_file)
# List of pages which failed to produce a correct output
failed_pages = []
# Generate the bitmap images
if dvips_failed:
# dvips failed, maybe there's a PDF, try to produce bitmaps
if use_pdftocairo:
conv_call = '%s -png -transp -r %d "%s" "%s"' \
% (pdftocairo, resolution, pdf_file, latex_file_root)
conv_status, conv_stdout = run_command(conv_call)
if not conv_status:
seqnum_re = re.compile("-([0-9]+)")
for name in glob.glob("%s-*.png" % latex_file_root):
match = seqnum_re.search(name)
if match != None:
new_name = seqnum_re.sub(str(int(match.group(1))), name)
os.rename(name, new_name)
else:
conv_call = '%s -dNOPAUSE -dBATCH -dSAFER -sDEVICE=%s ' \
'-sOutputFile="%s%%d.%s" ' \
'-dGraphicsAlphaBit=%d -dTextAlphaBits=%d ' \
'-r%f "%s"' \
% (gs, gs_device, latex_file_root, \
gs_ext, alpha, alpha, resolution, pdf_file)
conv_status, conv_stdout = run_command(conv_call)
if conv_status:
error(f"Failed: {os.path.basename(conv)} {pdf_file}")
else:
# Model for calling the converter on each file
if use_pdftocairo and epstopdf != None:
conv_call = '%s -png -transp -singlefile -r %d "%%s" "%s%%d"' \
% (pdftocairo, resolution, latex_file_root)
else:
conv_call = '%s -dNOPAUSE -dBATCH -dSAFER -sDEVICE=%s ' \
'-sOutputFile="%s%%d.%s" ' \
'-dGraphicsAlphaBit=%d -dTextAlphaBits=%d ' \
'-r%f "%%s"' \
% (gs, gs_device, latex_file_root, \
gs_ext, alpha, alpha, resolution)
i = 0
# Collect all the PostScript files (like *.001, *.002, ...)
ps_files = glob.glob("%s.[0-9][0-9][0-9]" % latex_file_root)
ps_files.sort()
# Call the converter for each file
for file in ps_files:
i = i + 1
progress(f"Processing page {i}, file {file}")
if use_pdftocairo and epstopdf != None:
conv_name = "epstopdf"
conv_status, conv_stdout = run_command(f"{epstopdf} --outfile={file}.pdf {file}")
if not conv_status:
conv_name = "pdftocairo"
file = file + ".pdf"
conv_status, conv_stdout = run_command(conv_call % (file, i))
else:
conv_name = "ghostscript"
conv_status, conv_stdout = run_command(conv_call % (i, file))
if conv_status:
# The converter failed, keep track of this
warning(f"{conv_name} failed on page {i}, file {file}")
failed_pages.append(i)
# Pass failed pages to pdflatex
if len(failed_pages) > 0:
warning("Now trying to obtain failed previews through pdflatex")
error_count = legacy_conversion_pdflatex(latex_file, failed_pages,
legacy_metrics, use_pdftocairo, conv, gs_device, gs_ext, alpha,
resolution, output_format)
else:
error_count = 0
# Invalidate metrics for pages that produced errors
if len(error_pages) > 0:
for index in error_pages:
if index not in failed_pages:
legacy_metrics.pop(index - 1)
legacy_metrics.insert(index - 1, (index, -1.0))
error_count += 1
# Crop the ppm images
if pnmcrop != None and output_format == "ppm":
crop_files(pnmcrop, latex_file_root)
# Allow to skip .metrics creation for custom management
# (see the dvipng method)
if not skipMetrics:
# Extract metrics info from the log file.
metrics_file = latex_file_re.sub(".metrics", latex_file)
write_metrics_info(legacy_metrics, metrics_file)
if error_count:
warning("Failed to produce %d preview snippet(s)" % error_count)
return (0, legacy_metrics)
if __name__ == "__main__":
sys.exit(legacy_conversion(sys.argv)[0])