The Tika preview extractor does a network call; it was using context.Background().
Pass the request context from the gRPC handler through Convert so the unpack call
respects cancellation and deadlines. Non-I/O decoders ignore the context.
Tika sniffs TIFF-based raws (NEF/DNG/ARW/PEF) as generic image/tiff by
content; only the filename extension routes them to the raw parser. Thread
the source name through to the unpack request via Content-Disposition.
Replace the in-process TIFF/BigTIFF walker (rawtiff.go) with a Tika-based
extractor: raw images are sent to a Tika server's /unpack endpoint, which
returns the embedded JPEG previews (Tika's RawTiffParser emits them as embedded
documents). The largest renderable JPEG is decoded through the image pipeline.
This aligns preview extraction with the search service (same Tika, same format
coverage) and drops a large hand-rolled parser. Raw thumbnails now require
THUMBNAILS_TIKA_TIKA_URL; without it, raw types fall back to the default decoder
(no thumbnail).
Audio artwork extraction stays in process for now and moves in a follow-up.
Both are TIFF-based camera raw formats handled by the same generic walker;
NRW detection needs the reva mimetype mapping in opencloud-eu/reva#773, SRF is
already mapped. No sample files on hand for these two, added by format
structure alongside their verified siblings.
Rename RawImageDecoder to RawTiffDecoder and qualify candidates by their
actual stream instead of trusting the tags: CR2 keeps its full-size JPEG
as an IFD0 strip, DNG stores the raw sensor payload as lossless JPEG
(SOF3) which starts with a regular SOI. A JPEG segment walk to the SOF
marker accepts only the DCT processes common decoders render.
For GeoGebra files we where still using the imaging package to decode the
embedded png, but handed it of to vips for scaling, which can't work. Now
we use vips for decoding the image as well.
Dominik Schmidt