Practical overview
When it fits
Use it after a recognition model has produced softmax probabilities in the required CTC tensor layout, when dictionary constraints or word-level language-model scoring are useful.
Who it is for
- Developers adding dictionary-constrained decoding to a CTC-based text-recognition pipeline.
- Researchers or engineers evaluating word-level language-model scoring for recognition outputs.
- Python users who want to call a C++ decoder component.
Documented uses
- Decode CTC model probability outputs into character-label sequences.
- Constrain candidate words using a corpus-derived dictionary.
- Optionally score word sequences with a language model.
- Preserve numbers, punctuation, or other non-word characters between recognized words.
Requirements & limits
The public GitHub repository is licensed under MIT. Its README documents a Python package installation path and lists Python 3.11 and 3.12 support.
- The input must be a NumPy array shaped time steps × batch × (characters + 1), with softmax already applied and the CTC blank in the final position.
- The supplied character sequence must match the recognition model’s output-class order.
- The corpus is used to build the dictionary and, in language-model modes, the language model; word characters determine how words are extracted.
- The four scoring modes trade off dictionary-only decoding, n-gram scoring, and forecast-based scoring; the forecast-and-sample mode considers at most 20 possible next words.
- The repository documents both a Python package interface and C++ implementation, plus a TensorFlow custom-operation extra.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Install the Python package and check installation
Install CTCWordBeamSearch from the repository and run its documented installation check.
Before you start
- The CTCWordBeamSearch repository.
- Python; the README lists support for Python 3.11 and 3.12.
- pytest for the documented test command.
Steps
From the repository root, run the command below.
pip install .Change to the
tests/directory and runpytestto check whether installation worked.
Expected outcome
The README’s installation check runs the repository tests with pytest.
Guide limitations
- This procedure checks installation; it does not configure a recognition model or demonstrate decoding.
- The README does not specify additional environment or platform setup in these steps.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 14 October 2026
- Original website title
- githubharald/CTCWordBeamSearch · Official homepage title · retained in its source language

