test: add tests for zimg RGB repacking

This tests the RGB repacker code in zimg, which deserves to be tested
because it's tricky and there will be more formats.

scale_test.c contains some code that can be used to test any scaler. Or
at least that would be great; currently it can only test repacking of
some byte-aligned-component RGB formats. It should be called
repack_test.c, but I'm too lazy to change the filename now.

The idea is that libswscale is used to cross-check the conversions
performed by the zimg wrapper. This is why it's "OK" that scale_test.c
does libswscale calls.

scale_sws.c is the equivalent to scale_zimg.c, and is of course
worthless (because it tests libswscale by comparing the results with
libswscale), but still might help with finding bugs in scale_test.c.

This borrows a sorted list of image formats from test/img_format.c, for
the same reason that file sorts them.

There's a slight possibility that this can be used to test vo_gpu.c too
some times in the future.

1 files changed, 8 insertions, 0 deletions

diff --git a/test/tests.h b/test/tests.h
index 0a589d984d..14e6f6ea63 100644
--- a/test/tests.h
+++ b/test/tests.h
@@ -41,6 +41,8 @@ extern const struct unittest test_gl_video;
 extern const struct unittest test_img_format;
 extern const struct unittest test_json;
 extern const struct unittest test_linked_list;
+extern const struct unittest test_repack_sws;
+extern const struct unittest test_repack_zimg;
 
 #define assert_true(x) assert(x)
 #define assert_false(x) assert(!(x))
@@ -69,3 +71,9 @@ void assert_text_files_equal_impl(const char *file, int line,
 
 // Open a new file in the out_path. Always succeeds.
 FILE *test_open_out(struct test_ctx *ctx, const char *name);
+
+// Sorted list of valid imgfmts. Call init_imgfmts_list() before use.
+extern int imgfmts[];
+extern int num_imgfmts;
+
+void init_imgfmts_list(void);