Python modules implementing OCR-D specs and related tools
This repository contains the python packages that form the base for tools within the OCR-D ecosphere.
All packages are also published to PyPI.
NOTE Unless you want to contribute to OCR-D/core, we recommend installation as part of ocrd_all which installs a complete stack of OCR-D-related software.
The easiest way to install is via pip
:
pip install ocrd
# or just the functionality you need, e.g.
pip install ocrd_modelfactory
All python software released by OCR-D requires Python 3.6 or higher.
NOTE Some OCR-D-Tools (or even test cases) might reveal an unintended behavior if you have specific environment modifications, like:
- using a custom build of ImageMagick, whose format delegates are different from what OCR-D supposes
- custom Python logging configurations in your personal account
NOTE: All OCR-D CLI tools support a --help
flag which shows usage and
supported flags, options and arguments.
A minimal OCR-D processor that copies from -I/-input-file-grp
to -O/-output-file-grp
Almost all behaviour of the OCR-D/core software is configured via CLI options and flags, which can be listed with the --help
flag that all CLI support.
Some parts of the software are configured via environement variables:
OCRD_METS_CACHING
: If set totrue
, access to the METS file is cached, speeding in-memory search and modification.OCRD_PROFILE
: This variable configures the built-in CPU and memory profiling. If empty, no profiling is done. Otherwise expected to contain any of the following tokens:CPU
: Enable CPU profiling of processor runsRSS
: Enable RSS memory profilingPSS
: Enable proportionate memory profiling
OCRD_PROFILE_FILE
: If set, then the CPU profile is written to this file for later peruse with a analysis tools like snakeviz
Contains utilities and constants, e.g. for logging, path normalization, coordinate calculation etc.
See README for ocrd_utils
for further information.
Contains file format wrappers for PAGE-XML, METS, EXIF metadata etc.
See README for ocrd_models
for further information.
Code to instantiate models from existing data.
See README for ocrd_modelfactory
for further information.
Schemas and routines for validating BagIt, ocrd-tool.json
, workspaces, METS, page, CLI parameters etc.
See README for ocrd_validators
for further information.
Depends on all of the above, also contains decorators and classes for creating OCR-D processors and CLIs.
Also contains the command line tool ocrd
.
See README for ocrd
for further information.
Builds a bash script that can be sourced by other bash scripts to create OCRD-compliant CLI.
For example:
source `ocrd bashlib filename`
declare -A NAMESPACES MIMETYPES
eval NAMESPACES=( `ocrd bashlib constants NAMESPACES` )
echo ${NAMESPACES[page]}
eval MIMETYPES=( `ocrd bashlib constants EXT_TO_MIME` )
echo ${MIMETYPES[.jpg]}
See CLI usage
Raise an error and exit.
Delegate logging to ocrd log
Ensure minimum version
Output ocrd-tool.json content verbatim.
Requires $OCRD_TOOL_JSON
and $OCRD_TOOL_NAME
to be set:
export OCRD_TOOL_JSON=/path/to/ocrd-tool.json
export OCRD_TOOL_NAME=ocrd-foo-bar
(Which you automatically get from ocrd__wrap
.)
Output given resource file's content.
Output all resource files' names.
Print help on CLI usage.
Parses arguments according to OCR-D CLI. In doing so, depending on the values passed to it, may delegate to …
ocrd__raise
and exit (if something went wrong)ocrd__usage
and exitocrd__dumpjson
and exitocrd__show_resource
and exitocrd__list_resources
and exitocrd validate tasks
and return
Expects an associative array ("hash"/"dict") ocrd__argv
to be defined
(to e filled by the parser):
declare -A ocrd__argv=()
Parses an ocrd-tool.json for a specific tool
(i.e. processor executable
).
(Delegates to ocrd__parse_argv
, creating the ocrd__argv
associative array.)
Usage: ocrd__wrap PATH/TO/OCRD-TOOL.JSON EXECUTABLE ARGS
For example:
ocrd__wrap $SHAREDIR/ocrd-tool.json ocrd-olena-binarize "$@"
Access information on the input files according to the parsed CLI arguments:
- their file
url
- their file
ID
- their
mimetype
- their
pageId
Usage: ocrd__input_file NR KEY
For example:
pageId=`ocrd__input_file 3 pageId`
To be used in conjunction with ocrd bashlib input-files
in a loop.
(Requires ocrd__wrap
to have been run first.)
Download assets (make assets
)
Test with local files: make test
- Test with remote assets:
make test OCRD_BASEURL='https://github.com/OCR-D/assets/raw/master/data/'
- OCR-D Specifications (Repo)
- OCR-D core API documentation (built here via
make docs
) - OCR-D Website (Repo)