https://github.com/ocr-d/ocrd_im6convert

Run ImageMagick with an OCR-D CLI
https://github.com/ocr-d/ocrd_im6convert

ocr-d

Last synced: about 1 year ago
JSON representation

Run ImageMagick with an OCR-D CLI

• Host: GitHub
• URL: https://github.com/ocr-d/ocrd_im6convert
• Owner: OCR-D
• License: apache-2.0
• Created: 2018-06-25T21:05:18.000Z (almost 8 years ago)
• Default Branch: master
• Last Pushed: 2024-10-01T17:37:11.000Z (over 1 year ago)
• Last Synced: 2025-03-24T11:38:25.815Z (about 1 year ago)
• Topics: ocr-d
• Language: Shell
• Homepage:
• Size: 43.9 KB
• Stars: 5
• Watchers: 4
• Forks: 3
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

Awesome Lists containing this project

README

          
# ocrd_imageconvert

> Thin wrapper around convert(1)

## Introduction

[ImageMagick's](https://imagemagick.org) `convert` CLI contains a treasure trove of image operations. This wrapper aims to provide much of that as an [OCR-D compliant processor](https://ocr-d.github.io/CLI).

## Installation

This module requires GNU make (for installation) and the ImageMagick command line tools (at runtime). On Ubuntu 18.04 (or similar), you can install them by running:

    sudo apt-get install make

    sudo make deps-ubuntu # or: apt-get install imagemagick

Moreover, an installation of [OCR-D core](https://github.com/OCR-D/core) is needed:

    make deps # or: pip install ocrd

This will install the Python package `ocrd` in your current environment. (Setting up a [venv](https://ocr-d.github.io/docs/guide#python-setup) is strongly recommended.)

Lastly, the provided shell script `ocrd-im6convert` works best when copied into your `PATH`, referencing its ocrd-tool.json under a known path. This can be done by running:

    make install

This will copy the binary and JSON file under `$PREFIX`, which variable you can override to your needs. The default value is to use `PREFIX=$VIRTUAL_ENV` if you have already activated a venv, or `PREFIX=$PWD/.local` (i.e. under the current working directory).

## Usage

This package provides `ocrd-im6convert` as a [OCR-D processor](https://ocr-d.github.com/cli) (command line interface). It uses the following parameters:

```JSON

    "ocrd-im6convert": {

      "executable": "ocrd-im6convert",

      "categories": ["Image preprocessing"],

      "steps": ["preprocessing/optimization"],

      "description": "Convert and transform images",

      "input_file_grp": [

        "OCR-D-IMG"

      ],

      "output_file_grp": [

        "OCR-D-IMG"

      ],

      "parameters": {

        "input-options": {

          "type": "string",

          "description": "e.g. -density 600x600 -wavelet-denoise 1%x0.1",

          "default": ""

        },

        "output-format": {

          "type": "string",

          "description": "Desired media type of output",

          "required": true,

          "enum": ["image/tiff", "image/jp2", "image/png"]

        },

        "output-options": {

          "type": "string",

          "description": "e.g. -resample 300x300 -alpha deactivate -normalize -despeckle -noise 2 -negate -morphology close diamond",

          "default": ""

        }

      }

    }

```

Cf. [IM documentation](https://imagemagick.org/script/command-line-options.php) or man-page `convert(1)` for formats and options.

### Example

    ocrd-im6convert -I OCR-D-IMG -O OCR-D-IMG-SMALL -p '{ "output-format": "image/png", "output-options": "-resize 24%" }'

(This downscales the images in the input file group `OCR-D-IMG` to 24% and stores them as PNG files under the output file group `OCR-D-IMG-SMALL`.)

## Testing

None yet