Crate wkb_raster

Crate wkb_raster 

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Well Known Binary format for PostGIS RASTER type

The WKB format for RASTER is meant for transport and takes into account endianness and avoids any padding. Still, beside padding and endianness, it matches the internal serialized format (see RFC1), for quick input/output.

§Example

§Raster to WKB string

use wkb_raster::{Raster, RasterBand, RasterDataSource, InMemoryRasterData, Endian};
 
// 2x2 image bytes, u8 format
let bytes = vec![
    vec![0, 1], 
    vec![1, 0],
];

let raster = Raster {
    endian: Endian::Big,    // note: currently Endian::Little is not supported in PostGIS
    version: 0,             // always set to 0
    scale_x: 1.0,           // pixel width in degrees
    scale_y: 1.0,           // pixel height in degrees
    ip_x: 0.0,              // upper left corner longitude in degrees
    ip_y: 0.0,              // upper left corner latitude in degrees
    skew_x: 0.0,            // rotation in degrees (0 to 360)
    skew_y: 0.0,            // rotation in degrees (0 to 360)
    srid: 4326,             // SRID EPSG identifier
    width: 2,               // pixel columns
    height: 2,              // rows
    bands: vec![RasterBand {
        is_nodata_value: false           // true only if entire band is NODATA
        data: RasterDataSource::InMemory(
            InMemoryRasterData::UInt8 {
                data: bytes,
                nodata
            }
        ),
    }],
};
 
assert_eq!(
    raster.to_wkb_string(), 
    String::from("00000000013FF00000000000003FF00000000000000000000000000000000000000000000000000000000000000000000000000000000010E600020002040000010100")
);

§WKB string to raster

use wkb_raster::{Raster, RasterBand, RasterDataSource, InMemoryRasterData, Endian};

let parsed_raster = Raster::from_wkb_string(b"00000000013FF00000000000003FF00000000000000000000000000000000000000000000000000000000000000000000000000000000010E600020002040000010100").unwrap();
 
// 2x2 image bytes, u8 format
let bytes = vec![
    vec![0, 1], 
    vec![1, 0],
];
 
assert_eq!(parsed_raster, Raster {
    endian: Endian::Big,
    version: 0,
    scale_x: 1.0,
    scale_y: 1.0,
    ip_x: 0.0,
    ip_y: 0.0,
    skew_x: 0.0,
    skew_y: 0.0,
    srid: 4326,
    width: 2,
    height: 2,
    bands: vec![RasterBand {
        is_nodata_value: false,
        data: RasterDataSource::InMemory(
            InMemoryRasterData::UInt8 {
                data: bytes,
                nodata
            }
        ),
    }],
});

Structs§

BoolParseError
OfflineRasterData
Raster data file source
Raster
Raster data
RasterBand
Single band of raster data

Enums§

Endian
Endianness of the output string
InMemoryRasterData
In-memory raster data with nodata value and
ParseError
PixType
Pixel type + optional nodata value
RasterDataSource
Source of the raster data bytes + pixel type definition