Rice1

class astropy.io.fits.hdu.compressed._codecs.Rice1(*, blocksize: int, bytepix: int, tilesize: int)

Bases: Codec

The FITS RICE1 compression and decompression algorithm.

The Rice algorithm [1] is simple and very fast It requires only enough memory to hold a single block of 16 or 32 pixels at a time. It codes the pixels in small blocks and so is able to adapt very quickly to changes in the input image statistics (e.g., Rice has no problem handling cosmic rays, bright stars, saturated pixels, etc.).

Parameters:

blocksize

The blocksize to use, each tile is coded into blocks a number of pixels wide. The default value in FITS headers is 32 pixels per block.

bytepix

The number of 8-bit buffer in each original integer pixel value.

References

[1]

Rice, R. F., Yeh, P.-S., and Miller, W. H. 1993, in Proc. of the 9th AIAA Computing in Aerospace Conf., AIAA-93-4541-CP, American Institute of Aeronautics and Astronautics [https://doi.org/10.2514/6.1993-4541]

Attributes Summary

codec_id

Methods Summary

decode(buf)	Decompress buffer using the RICE_1 algorithm.
encode(buf)	Compress the data in the buffer using the RICE_1 algorithm.

Attributes Documentation

codec_id = 'FITS_RICE1'

Methods Documentation

decode(buf)

Decompress buffer using the RICE_1 algorithm.

Parameters:

bufbytes or array_like

The buffer to decompress.

Returns:

bufnp.ndarray

The decompressed buffer.

encode(buf)

Compress the data in the buffer using the RICE_1 algorithm.

Parameters:

bufbytes or array_like

The buffer to compress.

Returns:

bytes

The compressed bytes.