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optimize: Modernize pikepdf usage

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This commit is contained in:
James R. Barlow
2019-02-16 14:03:10 -08:00
parent e2847ea4c3
commit 0bf26b03ae
1 changed files with 15 additions and 18 deletions
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src/ocrmypdf/optimize.py
+15 -18
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@@ -25,6 +25,7 @@ from pathlib import Path
from PIL import Image
import pikepdf
from pikepdf import Name, Dictionary
from . import leptonica
from ._jobcontext import JobContext
@@ -52,7 +53,7 @@ def tif_name(root, xref):
def extract_image_filter(pike, root, log, image, xref):
if image.Subtype != '/Image':
if image.Subtype != Name.Image:
return None
if image.Length < 100:
log.debug("Skipping small image, xref %s", xref)
@@ -68,7 +69,7 @@ def extract_image_filter(pike, root, log, image, xref):
if pim.bits_per_component > 8:
return None # Don't mess with wide gamut images
if filtdp[0] == '/JPXDecode':
if filtdp[0] == Name.JPXDecode:
return None # Don't do JPEG2000
return pim, filtdp
@@ -82,7 +83,7 @@ def extract_image_jbig2(*, pike, root, log, image, xref, options):
if (
pim.bits_per_component == 1
and filtdp != '/JBIG2Decode'
and filtdp != Name.JBIG2Decode
and jbig2enc.available()
):
try:
@@ -102,7 +103,7 @@ def extract_image_generic(*, pike, root, log, image, xref, options):
return None
pim, filtdp = result
if filtdp[0] == '/DCTDecode' and options.optimize >= 2:
if filtdp[0] == Name.DCTDecode and options.optimize >= 2:
# This is a simple heuristic derived from some training data, that has
# about a 70% chance of guessing whether the JPEG is high quality,
# and possibly recompressible, or not. The number itself doesn't mean
@@ -281,7 +282,7 @@ def convert_to_jbig2(pike, jbig2_groups, root, log, options):
if jbig2_symfile.exists():
jbig2_globals_data = jbig2_symfile.read_bytes()
jbig2_globals = pikepdf.Stream(pike, jbig2_globals_data)
jbig2_globals_dict = pikepdf.Dictionary({'/JBIG2Globals': jbig2_globals})
jbig2_globals_dict = Dictionary(JBIG2Globals=jbig2_globals)
elif options.jbig2_page_group_size == 1:
jbig2_globals_dict = None
else:
@@ -293,9 +294,7 @@ def convert_to_jbig2(pike, jbig2_groups, root, log, options):
jbig2_im_data = jbig2_im_file.read_bytes()
im_obj = pike.get_object(xref, 0)
im_obj.write(
jbig2_im_data,
filter=pikepdf.Name('/JBIG2Decode'),
decode_parms=jbig2_globals_dict,
jbig2_im_data, filter=Name.JBIG2Decode, decode_parms=jbig2_globals_dict
)
@@ -317,7 +316,7 @@ def transcode_jpegs(pike, jpegs, root, log, options):
compdata = leptonica.CompressedData.open(opt_jpg)
im_obj = pike.get_object(xref, 0)
im_obj.write(compdata.read(), filter=pikepdf.Name('/DCTDecode'))
im_obj.write(compdata.read(), filter=Name.DCTDecode)
def transcode_pngs(pike, pngs, root, log, options):
@@ -360,7 +359,7 @@ def transcode_pngs(pike, pngs, root, log, options):
predictor = None
if compdata.predictor > 0:
predictor = pikepdf.Dictionary({'/Predictor': compdata.predictor})
predictor = Dictionary(Predictor=compdata.predictor)
im_obj.BitsPerComponent = compdata.bps
im_obj.Width = compdata.w
@@ -371,23 +370,21 @@ def transcode_pngs(pike, pngs, root, log, options):
palette_data = pikepdf.Object.parse(palette_pdf_string)
palette_stream = pikepdf.Stream(pike, bytes(palette_data))
palette = [
pikepdf.Name('/Indexed'),
pikepdf.Name('/DeviceRGB'),
Name.Indexed,
Name.DeviceRGB,
compdata.ncolors - 1,
palette_stream,
]
cs = palette
else:
if compdata.spp == 1:
cs = pikepdf.Name('/DeviceGray')
cs = Name.DeviceGray
elif compdata.spp == 3:
cs = pikepdf.Name('/DeviceRGB')
cs = Name.DeviceRGB
elif compdata.spp == 4:
cs = pikepdf.Name('/DeviceCMYK')
cs = Name.DeviceCMYK
im_obj.ColorSpace = cs
im_obj.write(
compdata.read(), filter=pikepdf.Name('/FlateDecode'), decode_parms=predictor
)
im_obj.write(compdata.read(), filter=Name.FlateDecode, decode_parms=predictor)
def optimize(input_file, output_file, log, context):