Add 'auto' output type for best-effort PDF/A without Ghostscript

- Add new '--output-type auto' option (now the default) that produces
  best-effort PDF/A without requiring Ghostscript
- When verapdf is available, use speculative PDF/A conversion
- Without verapdf, pass through as PDF/A if safe (input claims PDF/A
  or --force-ocr was used), otherwise output as regular PDF
- Make Ghostscript check conditional - only required for pdfa* output types
- Update soft error tests to explicitly use --output-type pdfa since they
  exercise Ghostscript failure modes
- Fix Tesseract OSD error handling to check both stdout and stderr for
  known non-fatal messages like "Too few characters"
This commit is contained in:
James R. Barlow
2026-01-09 00:56:00 -08:00
parent bdc50e9470
commit 0c4ee5af4e
7 changed files with 153 additions and 51 deletions
+36 -33
View File
@@ -101,38 +101,41 @@ def add_options(parser):
@hookimpl
def check_options(options):
"""Check that the options are valid for this plugin."""
check_external_program(
program='gs',
package='ghostscript',
version_checker=ghostscript.version,
need_version='9.54', # RHEL 9's version; Ubuntu 22.04 has 9.55
)
gs_version = ghostscript.version()
if gs_version in BLACKLISTED_GS_VERSIONS:
raise MissingDependencyError(
f"Ghostscript {gs_version} contains serious regressions and is not "
"supported. Please upgrade to a newer version."
# Only require Ghostscript for pdfa* output types (not 'auto' or 'pdf')
# 'auto' mode uses best-effort PDF/A without Ghostscript fallback
if options.output_type.startswith('pdfa'):
check_external_program(
program='gs',
package='ghostscript',
version_checker=ghostscript.version,
need_version='9.54', # RHEL 9's version; Ubuntu 22.04 has 9.55
)
if Version('10.0.0') <= gs_version < Version('10.02.1') and (
options.skip_text or options.redo_ocr
):
raise MissingDependencyError(
f"Ghostscript 10.0.0 through 10.02.0 (your version: {gs_version}) "
"contain serious regressions that corrupt PDFs with existing text, "
"such as those processed using --skip-text or --redo-ocr. "
"Please upgrade to a "
"newer version, or use --output-type pdf to avoid Ghostscript, or "
"use --force-ocr to discard existing text."
)
if gs_version >= Version('10.6.0') and options.output_type.startswith('pdfa'):
log.warning(
"Ghostscript 10.6.x contains JPEG encoding errors that may corrupt "
"images. OCRmyPDF will attempt to mitigate, but this version is "
"strongly not recommended. Please upgrade to a newer version. "
"As of 2025-12, 10.6.0 is the latest version of Ghostscript."
)
if options.output_type == 'pdfa':
options.output_type = 'pdfa-2'
gs_version = ghostscript.version()
if gs_version in BLACKLISTED_GS_VERSIONS:
raise MissingDependencyError(
f"Ghostscript {gs_version} contains serious regressions and is not "
"supported. Please upgrade to a newer version."
)
if Version('10.0.0') <= gs_version < Version('10.02.1') and (
options.skip_text or options.redo_ocr
):
raise MissingDependencyError(
f"Ghostscript 10.0.0 through 10.02.0 (your version: {gs_version}) "
"contain serious regressions that corrupt PDFs with existing text, "
"such as those processed using --skip-text or --redo-ocr. "
"Please upgrade to a "
"newer version, or use --output-type pdf to avoid Ghostscript, or "
"use --force-ocr to discard existing text."
)
if gs_version >= Version('10.6.0'):
log.warning(
"Ghostscript 10.6.x contains JPEG encoding errors that may corrupt "
"images. OCRmyPDF will attempt to mitigate, but this version is "
"strongly not recommended. Please upgrade to a newer version. "
"As of 2025-12, 10.6.0 is the latest version of Ghostscript."
)
if options.output_type == 'pdfa':
options.output_type = 'pdfa-2'
if (
options.ghostscript.color_conversion_strategy
@@ -144,11 +147,11 @@ def check_options(options):
)
if (
options.ghostscript.pdfa_image_compression != 'auto'
and not options.output_type.startswith('pdfa')
and options.output_type not in ('auto', 'pdfa', 'pdfa-1', 'pdfa-2', 'pdfa-3')
):
log.warning(
"--pdfa-image-compression argument only applies when "
"--output-type is one of 'pdfa', 'pdfa-1', or 'pdfa-2'"
"--output-type is 'auto' or one of 'pdfa', 'pdfa-1', 'pdfa-2', 'pdfa-3'"
)