TiffParallelDecoder class

Decodes a TIFF/BigTIFF page in horizontal bands across a pool of isolates — the parallel counterpart to TiffImage.decodeRegionRgba8's single-call, single-core decode, for a page too large to want to decode serially. Every knob here (band height, chunk memory budget, worker count) is an explicit parameter the caller supplies — this class reads no process/OS memory state of its own and makes no assumption about how many CPU cores are safe to use; that judgment belongs to the caller, which is in a much better position to know what else is competing for the same machine's memory and cores.

Properties

hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Static Methods

decodeBanded({required String filePath, required int pageIndex, required int bandHeight, required int maxBytesPerChunk, required int workerCount, required void onBand(TiffBand band), void setUpIsolate()?}) → Future<void>
Decodes page pageIndex of the file at filePath in horizontal bands, spread across up to workerCount isolates — each opens its own handle on filePath (a decoded TiffImage and its underlying file handle can't cross an isolate boundary, so there's no way to share one already-open document across workers). onBand is called back on the caller's isolate once per decoded band, so it can do arbitrary work per band — write a file, accumulate into a buffer, feed a progress counter — without that work itself needing to be isolate-safe. Bands from different workers can interleave, so don't assume they arrive in increasing TiffBand.y order across the whole page (they do arrive in order within any one worker's own share of it).