Class: GeoTIFF
Defined in: geotiff.ts:35
A high-level GeoTIFF abstraction built on
@cogeotiff/core's Tiff and
TiffImage classes.
This class separates data IFDs from mask IFDs, pairs them by resolution level, and exposes sorted overviews. Intentionally mirrors the Python async-geotiff API as closely as possible.
Construct via GeoTIFF.fromUrl, GeoTIFF.fromArrayBuffer, GeoTIFF.open or GeoTIFF.fromTiff.
See
Overview for reduced-resolution overview images.
Properties
cachedTags
readonlycachedTags:CachedTags
Defined in: geotiff.ts:48
Cached TIFF tags that are pre-fetched when opening the GeoTIFF.
dataSource
readonlydataSource:Pick<Source,"fetch">
Defined in: geotiff.ts:56
The data source used for fetching tile data.
This is typically the raw source (e.g. HTTP or memory) rather than a layered source with caching and chunking, to avoid unnecessary copying of tile data through cache layers.
gdalMetadata
readonlygdalMetadata:GDALMetadata|null
Defined in: geotiff.ts:71
Parsed GDALMetadata tag, if present.
gkd
readonlygkd:GeoKeyDirectory
Defined in: geotiff.ts:68
The GeoKeyDirectory of the primary IFD.
image
readonlyimage:TiffImage
Defined in: geotiff.ts:62
The primary (full-resolution) TiffImage.
maskImage
readonlymaskImage:TiffImage|null
Defined in: geotiff.ts:65
The mask IFD of the full-resolution GeoTIFF, if any.
overviews
readonlyoverviews:Overview[]
Defined in: geotiff.ts:42
Reduced-resolution overview levels, sorted finest-to-coarsest.
Does not include the full-resolution image — use fetchTile on the GeoTIFF instance itself for that.
tiff
readonlytiff:Tiff
Defined in: geotiff.ts:59
The underlying Tiff instance.
Accessors
bbox
Get Signature
get bbox(): [
number,number,number,number]
Defined in: geotiff.ts:358
Bounding box [minX, minY, maxX, maxY] in the CRS.
Returns
[number, number, number, number]
count
Get Signature
get count():
number
Defined in: geotiff.ts:353
Number of bands (samples per pixel).
Returns
number
crs
Get Signature
get crs():
number|ProjJson
Defined in: geotiff.ts:279
The CRS parsed from the GeoKeyDirectory.
Returns an EPSG code (number) for EPSG-coded CRSes, or a PROJJSON object for user-defined CRSes. The result is cached after the first access.
See also GeoTIFF.epsg for the EPSG code directly from the TIFF tags.
Returns
number | ProjJson
height
Get Signature
get height():
number
Defined in: geotiff.ts:292
Image height in pixels.
Returns
number
isTiled
Get Signature
get isTiled():
boolean
Defined in: geotiff.ts:317
Whether the primary image is tiled.
Returns
boolean
nodata
Get Signature
get nodata():
number|null
Defined in: geotiff.ts:312
The no data value, or null if not set.
Returns
number | null
offsets
Get Signature
get offsets():
number[]
Defined in: geotiff.ts:339
The offset for each band (0-indexed), defaulting to 0.
Extracted from the GDALMetadata TIFF tag.
Returns
number[]
scales
Get Signature
get scales():
number[]
Defined in: geotiff.ts:348
The scale for each band (0-indexed), defaulting to 1.
Extracted from the GDALMetadata TIFF tag.
Returns
number[]
storedStats
Get Signature
get storedStats():
ReadonlyMap<number,BandStatistics> |null
Defined in: geotiff.ts:329
The pre-existing statistics for each band, if available.
Extracted from the GDALMetadata TIFF tag; never computed on demand. Keys are 1-based band indices to match GDAL's convention.
Returns null if no statistics are stored in the file.
Returns
ReadonlyMap<number, BandStatistics> | null
tileCount
Get Signature
get tileCount():
TiffImageTileCount
Defined in: geotiff.ts:297
The number of tiles in the x and y directions
Returns
TiffImageTileCount
tileHeight
Get Signature
get tileHeight():
number
Defined in: geotiff.ts:307
Tile height in pixels.
Returns
number
tileWidth
Get Signature
get tileWidth():
number
Defined in: geotiff.ts:302
Tile width in pixels.
Returns
number
transform
Get Signature
get transform():
Affine
Defined in: geotiff.ts:365
Return the dataset's georeferencing transformation matrix.
Returns
width
Get Signature
get width():
number
Defined in: geotiff.ts:287
Image width in pixels.
Returns
number
Methods
fetchTile()
Defined in: geotiff.ts:387
Fetch a single tile from the full-resolution image.
Parameters
x
number
The tile column index (0-based).
y
number
The tile row index (0-based).
options?
Optional parameters for fetching the tile.
boundless?
boolean
Whether to clip tiles that are partially outside the image bounds. When true, no clipping is applied. Defaults to true.
pool?
An optional DecoderPool for decoding the tile data. If not provided, a new decoder will be created for each tile.
signal?
An optional AbortSignal to cancel the fetch request.
Returns
index()
index(
x,y,op?): [number,number]
Defined in: geotiff.ts:410
Get the (row, col) pixel index containing the geographic coordinate (x, y).
Parameters
x
number
x coordinate in the CRS.
y
number
y coordinate in the CRS.
op?
(n) => number
Rounding function applied to fractional pixel indices. Defaults to Math.floor.
Returns
[number, number]
[row, col] pixel indices.
xy()
xy(
row,col,offset?): [number,number]
Defined in: geotiff.ts:426
Get the geographic (x, y) coordinate of the pixel at (row, col).
Parameters
row
number
Pixel row.
col
number
Pixel column.
offset?
Which part of the pixel to return. Defaults to "center".
"center" | "ul" | "ur" | "ll" | "lr"
Returns
[number, number]
[x, y] in the CRS.
fromArrayBuffer()
staticfromArrayBuffer(input):Promise<GeoTIFF>
Defined in: geotiff.ts:215
Create a GeoTIFF from an ArrayBuffer containing the entire file.
This is a convenience method that wraps the ArrayBuffer in a memory source and calls GeoTIFF.open. For large files, consider using GeoTIFF.fromUrl or GeoTIFF.open with a chunked HTTP source to avoid loading the entire file into memory at once.
Parameters
input
The ArrayBuffer containing the GeoTIFF file data.
Returns
Promise<GeoTIFF>
A Promise that resolves to a GeoTIFF instance.
fromTiff()
staticfromTiff(tiff,dataSource):Promise<GeoTIFF>
Defined in: geotiff.ts:122
Create a GeoTIFF from an already-initialised Tiff instance.
All IFDs are walked; mask IFDs are matched to data IFDs by matching (width, height). Overviews are sorted from finest to coarsest resolution.
Parameters
tiff
Tiff
dataSource
Pick<Source, "fetch">
A source for fetching tile data. This is separate from the source used to construct the TIFF to allow for separate caching implementations.
Returns
Promise<GeoTIFF>
fromUrl()
staticfromUrl(url,options?):Promise<GeoTIFF>
Defined in: geotiff.ts:232
Create a new GeoTIFF from a URL.
Parameters
url
The URL of the GeoTIFF to open.
string | URL
options?
Optional parameters for chunk size and cache size.
cacheSize?
number = ...
The size of the cache for recently accessed header chunks. Currently no caching is applied to data fetches. Defaults to 1MB.
chunkSize?
number = ...
The minimum size for each request made to the source while reading header metadata. Defaults to 32KB.
Returns
Promise<GeoTIFF>
A Promise that resolves to a GeoTIFF instance.
open()
staticopen(options):Promise<GeoTIFF>
Defined in: geotiff.ts:102
Open a GeoTIFF from a @cogeotiff/core Source.
This creates and initialises the underlying Tiff, then classifies IFDs.
Parameters
options
dataSource
Pick<Source, "fetch">
A source for fetching tile data. This is separate from the source used to construct the TIFF to allow for separate caching implementations.
headerSource
Source
The source used to construct the TIFF. This is typically a layered source with caching and chunking, to optimise access to TIFF tags and IFDs.
prefetch?
number
Number of bytes to prefetch when reading TIFF tags and IFDs. Defaults to 32KB, which is enough for most tags and small IFDs. Increase if you have many tags or large IFDs.
Returns
Promise<GeoTIFF>