Debug Options

The OPENSLIDE_DEBUG environment variable can contain a comma-separated list of debug options that will affect the behavior of the library. Pass OPENSLIDE_DEBUG=help for a list of debug options supported by your copy.

Options

decoding

Log non-fatal warnings emitted by format decoding libraries.

detection

Log the error message returned by each format driver that does not detect support for the specified slide file during openslide_detect_vendor(), openslide_can_open(), or openslide_open(). Useful if openslide_open() returns NULL when you think it shouldn’t.

jpeg-markers

For Hamamatsu VMS and NDPI slides, locate all restart markers and perform an extra verification pass before openslide_open() returns. Slow.

performance

Log conditions causing OpenSlide to exhibit suboptimal performance.

search

For formats that require searching the filesystem for related files, log each skipped file and the reason for skipping it.

sql

Log SQL queries performed by the SQLite decoder.

synthetic

Opening the empty filename with openslide_open("") opens a synthetic test slide that exercises all image decoders.

tiles

Draw tile outlines and coordinates in openslide_read_region() output.