Cross-attention
Cross-attention is an attention mechanism in which queries from one sequence or representation attend to keys and values from another.
Build a Text-to-Image Generator (from Scratch)
An attention mechanism that computes attention between decoder representations and representations from an encoded conditioning input.
- How it is used
- Connects decoder states to encoded source inputs during translation and image captioning.
- How deep it goes
- Specifies decoder-layer placement, query/key/value inputs, and a concrete call in code; does not elaborate the attention calculation here.
- Examples
- Uses German-to-English translation, a skiing-image caption, and a decoder-layer implementation with separate source and target masks.
- What you can do after
- Build it from scratch as a decoder sublayer that attends to encoder output for translation or image captioning.
Read how Build a Text-to-Image Generator (from Scratch) explains cross-attention →
Sutskever's List
An attention mechanism in which queries come from one sequence or representation and keys and values come from another.
- How it is used
- Aligns generated output with encoded input sequences inside an encoder-decoder generation pipeline.
- How deep it goes
- Defines Q/K/V separation and contextual alignment, but stops short of deriving attention scores or detailing implementation equations.
- Examples
- Uses translation alignment and a Transformer encoder-decoder schematic to illustrate selective source-context retrieval.
- What you can do after
- Apply it via encoder-decoder attention to guide token generation from encoded input representations.
Learn Generative AI with PyTorch
An attention operation where queries come from one sequence or representation and keys/values come from another, enabling information transfer between them.
- How it is used
- Connects decoder states to encoder representations so Transformers can generate translations conditioned on an input sequence.
- How deep it goes
- Traces queries, keys, scaled scores, softmax weights, decoder ordering, masks, residual connections, and layer normalization through code and diagrams.
- Examples
- Uses French translation tokens, encoder memory, a five-by-five target mask, attention-weight calculations, and a PyTorch DecoderLayer implementation.
- What you can do after
- Build it from scratch by assigning decoder queries and encoder keys and values within a Transformer decoder layer.
Read how Learn Generative AI with PyTorch explains cross-attention →
Machine Learning Algorithms in Depth
Cross-attention computes attention with queries from one sequence or representation source and keys and values from another.
- How it is used
- Associates decoder output positions with encoder representations during sequence generation and machine translation.
- How deep it goes
- Defines cross-attention through differing query, key, and value sources and explains its role, but does not derive numerical computation.
- Examples
- Uses neural machine translation, with decoder target tokens querying encoded input tokens.
- What you can do after
- Apply cross-attention to relate each generated target word to relevant words in an encoder-decoder transformer.
Read how Machine Learning Algorithms in Depth explains cross-attention →
Related concepts
- attentioncontrasts with · Attention is a neural-network mechanism that computes input-dependent weights to combine information according to its relevance to a computation.
- decoder layerused by · A decoder layer is a Transformer block that transforms target-sequence representations using masked self-attention, feed-forward processing, and optionally cross-attention to encoder outputs.
- decodeused by · Decoding is the process of transforming an encoded or internal representation into an interpretable or target-form output.
- key-value cacheuses · A key-value cache is a data structure that stores previously computed transformer attention keys and values for reuse during subsequent token generation.
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