video: add metadata handling for spherical video

This adds handling of spherical video metadata: retrieving it from
demux_lavf and demux_mkv, passing it through filters, and adjusting it
with vf_format. This does not include support for rendering this type of
video.

We don't expect we need/want to support the other projection types like
cube maps, so we don't include that for now. They can be added later as
needed.

Also raise the maximum sizes of stringified image params, since they
can get really long.

2 files changed, 16 insertions, 1 deletions

diff --git a/video/filter/vf.c b/video/filter/vf.c
index a126007498..0db6f2a286 100644
--- a/video/filter/vf.c
+++ b/video/filter/vf.c
@@ -224,7 +224,7 @@ void vf_print_filter_chain(struct vf_chain *c, int msglevel,
         return;
 
     for (vf_instance_t *f = c->first; f; f = f->next) {
-        char b[128] = {0};
+        char b[256] = {0};
         mp_snprintf_cat(b, sizeof(b), "  [%s] ", f->full_name);
         if (f->label)
             mp_snprintf_cat(b, sizeof(b), "\"%s\" ", f->label);
diff --git a/video/filter/vf_format.c b/video/filter/vf_format.c
index 1953b61ab6..581bbe332f 100644
--- a/video/filter/vf_format.c
+++ b/video/filter/vf_format.c
@@ -19,6 +19,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <inttypes.h>
+#include <math.h>
 
 #include <libavutil/rational.h>
 
@@ -46,6 +47,8 @@ struct vf_priv_s {
     int rotate;
     int dw, dh;
     double dar;
+    int spherical;
+    float spherical_ref_angles[3];
 };
 
 static bool is_compatible(int fmt1, int fmt2)
@@ -127,6 +130,13 @@ static int reconfig(struct vf_instance *vf, struct mp_image_params *in,
         dsize = av_d2q(p->dar, INT_MAX);
     mp_image_params_set_dsize(out, dsize.num, dsize.den);
 
+    if (p->spherical)
+        out->spherical.type = p->spherical;
+    for (int n = 0; n < 3; n++) {
+        if (isfinite(p->spherical_ref_angles[n]))
+            out->spherical.ref_angles[n] = p->spherical_ref_angles[n];
+    }
+
     // Make sure the user-overrides are consistent (no RGB csp for YUV, etc.).
     mp_image_params_guess_csp(out);
 
@@ -165,6 +175,10 @@ static const m_option_t vf_opts_fields[] = {
     OPT_INT("dw", dw, 0),
     OPT_INT("dh", dh, 0),
     OPT_DOUBLE("dar", dar, 0),
+    OPT_CHOICE_C("spherical", spherical, 0, mp_spherical_names),
+    OPT_FLOAT("spherical-yaw", spherical_ref_angles[0], 0),
+    OPT_FLOAT("spherical-pitch", spherical_ref_angles[1], 0),
+    OPT_FLOAT("spherical-roll", spherical_ref_angles[2], 0),
     OPT_REMOVED("outputlevels", "use the --video-output-levels global option"),
     OPT_REMOVED("peak", "use sig-peak instead (changed value scale!)"),
     {0}
@@ -178,5 +192,6 @@ const vf_info_t vf_info_format = {
     .options = vf_opts_fields,
     .priv_defaults = &(const struct vf_priv_s){
         .rotate = -1,
+        .spherical_ref_angles = {NAN, NAN, NAN},
     },
 };