large_image_source_dummy package¶
Module contents¶
- class large_image_source_dummy.DummyTileSource(*args, **kwargs)[source]¶
Bases:
TileSource
Initialize the tile class.
- Parameters
jpegQuality – when serving jpegs, use this quality.
jpegSubsampling – when serving jpegs, use this subsampling (0 is full chroma, 1 is half, 2 is quarter).
encoding – ‘JPEG’, ‘PNG’, ‘TIFF’, or ‘TILED’.
edge – False to leave edge tiles whole, True or ‘crop’ to crop edge tiles, otherwise, an #rrggbb color to fill edges.
tiffCompression – the compression format to use when encoding a TIFF.
style –
if None, use the default style for the file. Otherwise, this is a string with a json-encoded dictionary. The style can contain the following keys:
- band
if -1 or None, and if style is specified at all, the greyscale value is used. Otherwise, a 1-based numerical index into the channels of the image or a string that matches the interpretation of the band (‘red’, ‘green’, ‘blue’, ‘gray’, ‘alpha’). Note that ‘gray’ on an RGB or RGBA image will use the green band.
- frame
if specified, override the frame value for this band. When used as part of a bands list, this can be used to composite multiple frames together. It is most efficient if at least one band either doesn’t specify a frame parameter or specifies the same frame value as the primary query.
- framedelta
if specified and frame is not specified, override the frame value for this band by using the current frame plus this value.
- min
the value to map to the first palette value. Defaults to 0. ‘auto’ to use 0 if the reported minimum and maximum of the band are between [0, 255] or use the reported minimum otherwise. ‘min’ or ‘max’ to always uses the reported minimum or maximum.
- max
the value to map to the last palette value. Defaults to 255. ‘auto’ to use 0 if the reported minimum and maximum of the band are between [0, 255] or use the reported maximum otherwise. ‘min’ or ‘max’ to always uses the reported minimum or maximum.
- palette
a list of two or more color strings, where color strings are of the form #RRGGBB, #RRGGBBAA, #RGB, #RGBA, or any string parseable by the PIL modules, or, if it is installed, byt matplotlib. Alternately, this can be a single color, which implies [‘#000’, <color>], or the name of a palettable paletter or, if available, a matplotlib palette.
- nodata
the value to use for missing data. null or unset to not use a nodata value.
- composite
either ‘lighten’ or ‘multiply’. Defaults to ‘lighten’ for all except the alpha band.
- clamp
either True to clamp (also called clip or crop) values outside of the [min, max] to the ends of the palette or False to make outside values transparent.
Alternately, the style object can contain a single key of ‘bands’, which has a value which is a list of style dictionaries as above, excepting that each must have a band that is not -1. Bands are composited in the order listed.
- classmethod canRead(*args, **kwargs)[source]¶
Check if we can read the input. This takes the same parameters as __init__.
- Returns
True if this class can read the input. False if it cannot.
- extensions = {None: 9}¶
A dictionary of known file extensions and the
SourcePriority
given to each. It must contain a None key with a priority for the tile source when the extension does not match.
- getTile(x, y, z, **kwargs)[source]¶
Get a tile from a tile source, returning it as an binary image, a PIL image, or a numpy array.
- Parameters
x – the 0-based x position of the tile on the specified z level. 0 is left.
y – the 0-based y position of the tile on the specified z level. 0 is top.
z – the z level of the tile. May range from [0, self.levels], where 0 is the lowest resolution, single tile for the whole source.
pilImageAllowed – True if a PIL image may be returned.
numpyAllowed – True if a numpy image may be returned. ‘always’ to return a numpy array.
sparseFallback – if False and a tile doesn’t exist, raise an error. If True, check if a lower resolution tile exists, and, if so, interpolate the needed data for this tile.
frame – the frame number within the tile source. None is the same as 0 for multi-frame sources.
- Returns
either a numpy array, a PIL image, or a memory object with an image file.
- name = 'dummy'¶
Name of the tile source