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A RocketRide filter node that generates a 128×128 PNG thumbnail from an input image.

What it does​

Resizes incoming images into compact, fixed-size thumbnails. It accepts either a raw image stream or Image documents, and outputs the resized result downstream. Useful for creating lightweight image previews before passing them to a vision LLM, reducing token usage and processing time compared to full-resolution images.

Uses Pillow (via the shared ai.common.image.ImageProcessor helper, the node itself declares no extra requirements). Thumbnails are produced by stepwise downscaling (halving until the larger side is ≤ 256 px, which avoids aliasing), an aspect-ratio-preserving resize, and a final center crop to exactly 128×128 pixels. Output is always encoded as PNG, preserving transparency.

The node is registered as a filter with class type image and has no configurable fields.

Configuration​

Lanes​

Lane inLane outDescription
imageimageResize raw image to thumbnail
imagedocumentsResize raw image and emit as document
documentsdocumentsResize image documents to thumbnail

image lane in​

Raw image data arrives as a chunked stream (BEGIN / WRITE / END). The node buffers all chunks, loads the complete image once the stream ends, and generates the thumbnail. It then emits on whichever output lanes have listeners attached:

  • documents listener: the thumbnail is base64-encoded (PNG) and emitted as a single Doc of type Image with fresh metadata (chunkId, isTable: false, tableId: 0, isDeleted: false).
  • image listener: the thumbnail is emitted as raw PNG bytes in a new BEGIN / WRITE / END stream, keeping the incoming MIME type.

documents lane in​

Each incoming Doc of type Image has its base64 content decoded, thumbnailed, and re-emitted as a new Image document with the original metadata preserved. Documents are skipped with a warning (not an error) when they are not of type Image, have empty content, or fail to decode/process, the remaining documents in the batch are still processed.

None. The node's shape defines no properties; the thumbnail size (128×128) is fixed.

Schema​

No configuration fields.