BartDecoder class

Complete BART decoder for Donut.

Generates token sequences auto-regressively given encoder outputs. Uses cross-attention to attend to the encoder's visual features.

The decoder operates in two modes:

Full sequence mode: Process entire input sequence (for prefilling)
Single token mode: Process one token at a time with KV cache (for auto-regressive generation)

Constructors

BartDecoder({int decoderLayers = 4, int maxPositionEmbeddings = 1536, int vocabSize = 57525, int embedDim = 1024, int ffnDim = 4096, int numHeads = 16})

decoderLayers → int: final
embedDim → int: final
embedPositions ↔ Embedding: getter/setter pair
embedScale ↔ double: Scaling factor for embeddings (sqrt(embedDim)).
getter/setter pair
embedTokens ↔ Embedding: getter/setter pair
ffnDim → int: final
hashCode → int: The hash code for this object.
no setterinherited
layerNorm ↔ LayerNorm: getter/setter pair
layernormEmbedding ↔ LayerNorm: getter/setter pair
layers ↔ List<BartDecoderLayer>: getter/setter pair
lmHead ↔ Linear: getter/setter pair
maxPositionEmbeddings → int: final
numHeads → int: final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
tokenizer ↔ DonutTokenizer?: The tokenizer for encoding/decoding text.
getter/setter pair
vocabSize → int: final

addSpecialTokens(List<String> tokens) → void: Add special tokens to the tokenizer vocabulary.
forward(List<int> inputIds, {required Tensor encoderHiddenStates, KVCache? cache, int pastLength = 0}) → (Tensor, KVCache): Forward pass through the decoder.
generate({required Tensor encoderOutput, required List<int> promptTokens, int maxLength = 1536, int? eosTokenId, int? padTokenId, bool greedy = true}) → List<int>: Generate a token sequence auto-regressively.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
resizeVocab(int newVocabSize) → void: Resize vocabulary to newVocabSize, preserving pretrained weights.
toString() → String: A string representation of this object.
inherited