Quickstart
==========

PyImgBatch is a batch image processor for python including a command
line interface.

Installation
------------

For installation open a terminal and type the following line into the
command line.

::

    pip install pyimgbatch

Usage on command line
---------------------

The simplest usage is to change to the folder containing the images with

::

    cd /folder/wit/images

and type

::

    pyimgbatch --width 300

This will resize all supported image files in the current folder to a
width of 300 pixels respecting the aspect ratio of the source file. The
results will be written to a "dest" subfolder.

Alternatively, you can set a source folder with the images to be
converted and/or a destination folder for the results as follow.

::

    pyimgbatch --source source_folder --dest destination_folder --height 400

or shorter

::

    pyimgbatch -s source_folder -d destination_folder --height 400

This will convert the images from the *source\_folder* to a height of
400px and stores the results in the destination folder.

*Note: For every source image a subfolder will be created inside the
destination\_folder. To avoid this behavior use the --nosubfolder
argument.*

Project Files
-------------

One of PyImgBatch features is to create multiple different versions from
given image files.

For this, you can use project files. Project files are JSON files
containing the specifications for the image processing.

The very short one
~~~~~~~~~~~~~~~~~~

Here an example of a very short one.

.. code:: json

    [
        { "width": 1000, "suffix": ".w1000" },
        { "height": 1200, "suffix": ".h1200" }
    ]

For example (may the project named "myprj.json"):

::

    pyimgbatch -c myprj.json

produces the following output:

::

    processing: french-bulldog-4530685.jpg
    creating: french-bulldog-4530685.w1000.jpg
    creating: french-bulldog-4530685.h1200.jpg
    processing: coast-4478424.jpg
    creating: coast-4478424.w1000.jpg
    creating: coast-4478424.h1200.jpg
    ...
    processing: beaded-2137080_1920-cmyk-iso-eci.tif
    creating: beaded-2137080_1920-cmyk-iso-eci.w1000.jpg
    creating: beaded-2137080_1920-cmyk-iso-eci.h1200.jpg
    ...

and creates two images per source images, resized to the specified width
or height with suffix added to the original name.

The short one
~~~~~~~~~~~~~

Imagine, you need to create different sizes for all your images for
your web project. For instance, you need the images in widths 180px,
300px, 400px and one in a height of 800 and each 2x and 3x the size for
higher pixel density display like in smartphones.

An example could look as follow.

.. code:: JSON

    {
        "name": "web set",
        "comment": "some sample pictures",
        "source": "webset/source",
        "dest": "webset/dest",
        "prefix": "web.",
        "configs": [
            { "width": 180, "suffix": ".w180", "webset": "@3x" },
            { "width": 300, "suffix": ".w300", "webset": "@3x" },
            { "width": 400, "suffix": ".w400", "webset": "@3x" },
            { "height": 800, "prefix": "preview.", "webset": "@3x" }
        ]
    }

This will create 12 destination images for each imput image. For a image
"lama-4540160.jpg" you get:

::

    ...
    creating: lama-4540160/web.lama-4540160.w180@1x.jpg
    creating: lama-4540160/web.lama-4540160.w180@2x.jpg
    creating: lama-4540160/web.lama-4540160.w180@3x.jpg
    creating: lama-4540160/web.lama-4540160.w300@1x.jpg
    creating: lama-4540160/web.lama-4540160.w300@2x.jpg
    creating: lama-4540160/web.lama-4540160.w300@3x.jpg
    creating: lama-4540160/web.lama-4540160.w400@1x.jpg
    creating: lama-4540160/web.lama-4540160.w400@2x.jpg
    creating: lama-4540160/web.lama-4540160.w400@3x.jpg
    creating: lama-4540160/preview.lama-4540160@1x.jpg
    creating: lama-4540160/preview.lama-4540160@2x.jpg
    creating: lama-4540160/preview.lama-4540160@3x.jpg
    ...

As you see you can specify defaults, so you don't need to repeat
yourself.

The more specific option is used instead of the more general one. So
in this example, all images get the prefix "web." except the last,
because the more specific prefix is here given as "preview."

*Hint: The file names are a little strange because I've downloaded the
from the free image stock `pixabay <https://pixabay.com>`__ and I
haven't changed the Name so you can search for the pics or the
photographer if you want.*

Full image project file
~~~~~~~~~~~~~~~~~~~~~~~

looks as follow.

.. code:: JSON

    {
        "comment": "pyImgBatch demo project",
        "debug": true,
        "no-progess": false,
        "projects": [
            {
                "name": "web set",
                "comment": "some sample pictures",
                "source": "webset/source",
                "dest": "webset/dest",
                "prefix": "web.",
                "configs": [
                    { "width": 180, "suffix": ".w180", "webset": "@3x" },
                    { "width": 300, "suffix": ".w300", "webset": "@3x" },
                    { "width": 400, "suffix": ".w400", "webset": "@3x" },
                    { "height": 800, "prefix": "preview.", "webset": "@3x" }
                ]
            },
            {
                "name": "images to thumbnails",
                "source": "to-thumbnails/originals",
                "dest": "to-thumbnails/thumbnails",
                "subfolder": false,
                "prefix": "thumb.",
                "configs": [
                    {"height": 300}, 
                    {"prefix": "smallthumb.", "height": 200}
                ]
            }
        ]
    }

This project contains two projects.