ppmflash

Generate a PPM image as output that is flashfactor times brighter than the input PPM image

$ ppmflash [flashfactor] [path/to/file.ppm] > [path/to/file.ppm]

$ ppmflash [[-v|-version]]

`ppmflash` [ppmfile]

Description:
The `ppmflash` command reads a Portable Pixmap (PPM) image, applies a flash photography effect, and writes the resulting PPM image. If ppmfile is not specified, `ppmflash` reads from standard input. The output is always written to standard output.

`ppmflash` is a Netpbm command-line utility designed to simulate the effect of a photographic flash on a Portable Pixmap (PPM) image. It achieves this by significantly brightening the input image, particularly the darker regions, and compressing the color range. This process mimics the high contrast, flattened appearance, and often slightly overexposed look characteristic of flash photography. The command processes one PPM image at a time, reading from standard input by default and writing the modified image to standard output. It's a simple yet effective tool for creating a stylized, high-impact visual effect, often used in conjunction with other Netpbm filters for more complex image manipulations.

Fixed Effect: `ppmflash` does not offer any command-line options or parameters to adjust the intensity or characteristics of the flash effect. The transformation applied is predetermined.

PPM Format Only: This command exclusively operates on Portable Pixmap (PPM) images. Attempting to use it with other image formats will result in an error, though Netpbm tools like `anytopnm` can convert other formats to PPM beforehand.

Like many Netpbm utilities, `ppmflash` adheres to the Unix philosophy of doing one thing well. It's designed to be a simple filter that can be easily integrated into shell scripts and pipelines, allowing users to combine its specific effect with other Netpbm commands for more intricate image transformations.

`ppmflash` is an integral part of the Netpbm project, a suite of graphics utilities for converting and manipulating images. The command was authored by Greg Roelofs and became part of the Netpbm distribution, which originated from the Pbmplus package developed by Jef Poskanzer in the late 1980s. `ppmflash` exemplifies Netpbm's philosophy of providing simple, specialized tools that can be chained together via pipelines to perform complex image processing tasks. Its functionality has remained consistent, focusing solely on applying a fixed flash effect to PPM images.

netpbm(1), ppm(5), ppmbrighten(1), ppmgamma(1), pnmremap(1), anytopnm(1)