resample - resample a picture resample [ -x size ] [ -y size ] [ file ] Resample resamples its input image (default standard input) to a new size. The image is decimated or interpolated using a Kaiser window.

The size of the resampled image can be specified with the -x and -y options. An unadorned value sets the number of pixels of that dimension; a suffixed percent sign specifies a percentage. If only one of -x or -y is given, the other dimension is scaled to preserve the aspect ratio of the original image. Thus, -x50% will reduce the image to half its original dimension in both x and y .

The input should be a Plan 9 image as described in image (6), and the output will be a compressed 24-bit r8g8b8 image. To uncompress the image or change the pixel format, use iconv (see crop (1)).

/sys/src/cmd/resample.c crop (1), image (6) Faster algorithms exist, but this implementation produces correct pictures.