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, 45 insertions, 0 deletions

diff --git a/test/scale_sws.c b/test/scale_sws.c
new file mode 100644
index 0000000000..bfc3bb93ae
--- /dev/null
+++ b/test/scale_sws.c
@@ -0,0 +1,45 @@
+// Test scaling using libswscale.
+// Note: libswscale is already tested in FFmpeg. This code serves mostly to test
+//       the functionality scale_test.h using the already tested libswscale as
+//       reference.
+
+#include "scale_test.h"
+#include "video/sws_utils.h"
+
+static bool scale(void *pctx, struct mp_image *dst, struct mp_image *src)
+{
+    struct mp_sws_context *ctx = pctx;
+    return mp_sws_scale(ctx, dst, src) >= 0;
+}
+
+static bool supports_fmts(void *pctx, int imgfmt_dst, int imgfmt_src)
+{
+    struct mp_sws_context *ctx = pctx;
+    return mp_sws_supports_formats(ctx, imgfmt_dst, imgfmt_src);
+}
+
+static const struct scale_test_fns fns = {
+    .scale = scale,
+    .supports_fmts = supports_fmts,
+};
+
+static void run(struct test_ctx *ctx)
+{
+    struct mp_sws_context *sws = mp_sws_alloc(NULL);
+
+    struct scale_test *stest = talloc_zero(NULL, struct scale_test);
+    stest->fns = &fns;
+    stest->fns_priv = sws;
+    stest->test_name = "repack_sws";
+    stest->ctx = ctx;
+
+    repack_test_run(stest);
+
+    talloc_free(stest);
+    talloc_free(sws);
+}
+
+const struct unittest test_repack_sws = {
+    .name = "repack_sws",
+    .run = run,
+};