imgp(1) · carta

NAME

imgp - Resize, rotate JPEG and PNG images.

SYNOPSIS

imgp [OPTIONS] [PATH [PATH ...]]

DESCRIPTION

imgp is a multiprocessing command line image resizer and rotator for JPEG and PNG images.

Features

* resize by percentage or resolution
* rotate clockwise by specified angle
* adaptive resize considering orientation
* brute force to a resolution
* optimize images to save more space
* limit processing by minimum image size
* convert PNG to JPEG
* erase exif metadata
* specify output JPEG image quality
* force smaller to larger resize
* process directories recursively
* overwrite source image option

Adaptive mode

- If the specified and image orientations are same [(H >= V and h > v) or (H < V and h < v)], the image is resized with the longer specified side as reference.
- In case of cross orientation [(H >= V and h <= v) or (H < V and h >= v)], the image is resized with the shorter specified side as reference. Same as non-adaptive.

For example, if an image has a resolution of 2048x1365 and is being resized to 1366x768:
- In regular mode (default), output image resolution will be 1152x768
- In adaptive mode, output image resolution will be 1366x910

Operational notes

- Multiple files and directories can be specified as source. If PATH is omitted, the current directory is processed.
- Output image names are appended with _IMGP if '--overwrite' option is not used. By default _IMGP files are not processed. Doing so may lead to potential race conditions when '--overwrite' option is used.
- PNG files with lower target hres/vres are not converted (even if '--convert' is used). Run 'imgp --convert (*.png)' separately to convert those.
- Resize and rotate are lossy operations. For additional reductions in size try '--optimize' and '--eraseexif' options.
- Option '--optimize' is slower, the encoder makes an extra pass over the image in order to select optimal encoder settings.
- Progressive JPEG images are saved as progressive.

OPTIONS

-h, --help: Show help text and exit.

-x, --res=res: Output resolution in HRESxVRES or percentage.

-o, --rotate=deg: Rotate clockwise by a specified angle (in degrees). Negative inputs rotate anti-clockwise. Rotation by 0 degree is not allowed.

-a, --adapt: Adapt to specified resolution considering the orientation of the image. Disabled by default.

-c, --convert: Convert PNG images to JPEG to save on space. The output image is saved with '.jpg' extension.

-e, --eraseexif: Erase EXIF metadata of JPEG images. Preserved by default.

-f, --force: Force to the exact specified resolution. Disabled by default.

-H, --hidden: Include hidden (dot) files. By default hidden files are skipped. -i, --includeimgp Process _IMGP files. Risky due to potential race conditions.

-k, --keep: Do not process if image hres or vres matches specified hres or vres, or --res is 100. However, PNG images are converted to JPEG if --convert option is specified and JPEG images are made progressive is --progressive option is specified.

-n, --enlarge: Enlarge smaller images. By default smaller images are not scaled if specified resolution is greater.

-N --nearest: Use nearest neighbour interpolation for PNG images instead of default antialias.

-p, --optimize: Optimize output images using PIL library optimization algorithm. Disabled by default.

-P, --progressive: Save all output JPEG images as progressive, even if the source is not.

-q, --quality=N: Save the image with a specified quality factor N (scale 1-95, default 75). JPEG only.

-m, --mute: Do not show any operational output.

-M, --minresres: minimum resolution in HxV or percentage of --res to resize

-r, --recurse: Recursively process sub-directories. By default only the specified directory is processed. Symbolic links are ignored to avoid recursive loops.

-s, --size=byte: Minimum size in bytes required to process an image. Acts as a guard against processing low-resolution images. Default 1024 bytes.

-w, --overwrite: Overwrite the source images. By default an output image is saved with _IMGP appended to the source image name.
NOTE: If overwrite and convert options are used together, source PNG images are deleted.

-d, --debug: Enable debugging.

EXAMPLES

1.: Convert some images and directories:

$ imgp -x 1366x768 ~/ ~/Pictures/image3.png ~/Downloads/ /home/testuser/image1.png 3840x2160 -> 1365x768 11104999 bytes -> 1486426 bytes

/home/testuser/image2.jpg 2048x1365 -> 1152x768 224642 bytes -> 31421 bytes

/home/testuser/Pictures/image3.png 1920x1080 -> 1365x768 2811155 bytes -> 1657474 bytes

/home/testuser/Downloads/image4 2048x1365 -> 1152x768 224642 bytes -> 31421 bytes

2.: Scale an image by 75% and overwrite the source image:

: $ imgp -x 75 -w ~/image.jpg /home/testuser/image.jpg 1366x767 -> 1025x575 120968 bytes -> 45040 bytes

3.: Rotate an image clockwise by 90 degrees:

: $ imgp -o 90 ~/image.jpg 120968 bytes -> 72038 bytes

4.: Adapt the images in the current directory to 1366x1000 resolution.
Visit all directories recursively, overwrite source images, ignore images with matching hres or vres but convert PNG images to JPEG.

: $ imgp -x 1366x1000 -wrack

5.: Set hres=800 and adapt vres maintaining the ratio.

$ imgp -x 800x0 Source omitted. Processing current directory...

./image1.jpg 1366x911 -> 800x534 69022 bytes -> 35123 bytes

./image2.jpg 1050x1400 -> 800x1067 458092 bytes -> 78089 bytes

6.: Process images greater than 50KiB only:

: $ imgp -wrackx 1366x1000 -s 51200

7.: Generate a 64px adaptive thumbnail of the last modified file in the current dir:

#!/usr/bin/env sh

thumb64 () {
pop=$(ls -1t | head -1)
imgp -acx 64x64 "$pop" }

AUTHORS

Arun Prakash Jana <[email protected]>

HOME

https://github.com/jarun/imgp

REPORTING BUGS

https://github.com/jarun/imgp/issues

LICENSE

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.