Sparse walkers, truncated MEF/lossy-JPEG strips, embedded JPEG sizes, the
CR3 preview marker walk, OpcodeList3 full-image passes and caller-supplied
Deflate tile edges each let a small file or one bad argument multiply
allocations or CPU work thousands of times. Each path now is bounded,
every fix with a regression test that failed (or blew up) before it, plus
a tiff::image single_chunk helper so preview extraction never builds a
descriptor vector for a hostile multi-strip layout.
Dylan M. Taylor
d00df6319c