Expand description
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§
- Bool
Parse Error - Offline
Raster Data - Raster data file source
- Raster
- Raster data
- Raster
Band - Single band of raster data
Enums§
- Endian
- Endianness of the output string
- InMemory
Raster Data - In-memory raster data with nodata value and
- Parse
Error - PixType
- Pixel type + optional nodata value
- Raster
Data Source - Source of the raster data bytes + pixel type definition