Next: , Previous: , Up: Internal Routines   [Contents][Index]

15.5.339 jpegread

jpegread, var, file [, header, shrink=shrink] [, /greyscale]

jpegread(var, file [, header, shrink=shrink] [, /greyscale])

[jpeg] Retrieves array and header from jpeg-compressed file. If header is not specified, then any header is displayed on the screen. If shrink is specified, then the image is shrunk by the indicated factor (which must be 1, 2, 4, or 8) before being returned. If /greyscale is selected, then a greyscale image is returned even if the file contains a color image. Specifying /greyscale and specifying a non-unit value for shrink decreases the amount of time that the reading and decompression takes. rgb values are returned in a three-dimensional array, with the first dimension (of size three) selecting the color and the remaining dimensions selecting location. Greyscale values are returned in a two-dimensional array.

The function returns 1 on success, 0 on failure. The subroutine generates an error on failure.

LUX uses version 6b of the Independent jpeg Group’s jpeg library to implement this routine.

See also: jpegwrite, fzread, gifread