Bitmask

Functions
int	epr_read_bitmask_raster (EPR_SProductId *product_id, const char *bm_expr, int offset_x, int offset_y, EPR_SRaster *raster)
	Calculates a bit-mask, composed of flags of the given product and combined as described in the given bit-mask expression, for the a certain dimension and sub-sampling as defined in the given raster.

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Function Documentation

int epr_read_bitmask_raster	(	EPR_SProductId *	product_id,
		const char *	bm_expr,
		int	offset_x,
		int	offset_y,
		EPR_SRaster *	raster
	)

Calculates a bit-mask, composed of flags of the given product and combined as described in the given bit-mask expression, for the a certain dimension and sub-sampling as defined in the given raster.

Parameters:

	product_id	Identifier of the ENVISAT product for which the bit-mask shall be created. This is used by the function to retreive the needed flags.
	bm_expr	A string holding the logical expression for the defintion of the bit-mask. In a bit-mask expression, any number of the flag-names (found in the DDDB) can be composed with "(", ")", "NOT", "AND", "OR". Valid bit-mask expression are for example: "flags.LAND OR flags.CLOUD" or "NOT flags.WATER AND flags.TURBID_S".
	offset_x	across-track co-ordinate in pixel co-ordinates (zero-based) of the upper right corner of the source-region
	offset_y	along-track co-ordinate in pixel co-ordinates (zero-based) of the upper right corner of the source-region
	raster	the raster for the bit-mask. The data type of the raster must be either e_tid_uchar or e_tid_char.

Returns:

zero for success, an error code otherwise

See also:

create_band_raster