dcpomatic/test, branch v2.15.152

Bump libdcp for fix to decryption of SMPTE subtitles.

2021-05-27T12:27:22Z

Also add a test for that.

Fix potential very rare test failure.

2021-05-26T18:05:49Z

Remove privilege escalation via seteuid() etc. on Linux.

2021-05-26T18:05:49Z

Move video level conversion for RGB from FFmpegImageProxy to Image.

2021-05-25T19:35:12Z

Since FFmpeg does not do video level conversion for RGB sources when we (sort of) ask it to in Image::crop_scale_window() it seems to make more sense to compensate for that by calling full_to_video_range() in the same place (rather than in FFmpegImageProxy).

Clamp results correctly when shifting video levels, and account for that in tests.

2021-05-25T19:35:12Z

Make a test check more informative.

2021-05-25T19:35:12Z

Use decoder_factory() and a lambda to clean things up a bit.

2021-05-25T19:35:12Z

Don't apply the Windows long path fix twice.

2021-05-11T14:09:20Z

Remove erroneous call to optional_node_child().

2021-05-09T20:07:51Z

Just after this we loop over all nodes, and optional_node_child will raise an exception if there is more than one.

C++11 tidying.

2021-05-09T20:07:32Z