video: switch from using display aspect to sample aspect

MPlayer traditionally always used the display aspect ratio, e.g. 16:9,
while FFmpeg uses the sample (aka pixel) aspect ratio.

Both have a bunch of advantages and disadvantages. Actually, it seems
using sample aspect ratio is generally nicer. The main reason for the
change is making mpv closer to how FFmpeg works in order to make life
easier. It's also nice that everything uses integer fractions instead
of floats now (except --video-aspect option/property).

Note that there is at least 1 user-visible change: vf_dsize now does
not set the display size, only the display aspect ratio. This is
because the image_params d_w/d_h fields did not just set the display
aspect, but also the size (except in encoding mode).

1 files changed, 5 insertions, 1 deletions

diff --git a/video/mp_image.h b/video/mp_image.h
index f71f7b3652..c2841490f4 100644
--- a/video/mp_image.h
+++ b/video/mp_image.h
@@ -40,7 +40,7 @@
 struct mp_image_params {
     enum mp_imgfmt imgfmt;      // pixel format
     int w, h;                   // image dimensions
-    int d_w, d_h;               // define display aspect ratio (never 0/0)
+    int p_w, p_h;               // define pixel aspect ratio (never 0/0)
     enum mp_csp colorspace;
     enum mp_csp_levels colorlevels;
     enum mp_csp_prim primaries;
@@ -137,6 +137,10 @@ bool mp_image_params_valid(const struct mp_image_params *p);
 bool mp_image_params_equal(const struct mp_image_params *p1,
                            const struct mp_image_params *p2);
 
+void mp_image_params_get_dsize(const struct mp_image_params *p,
+                               int *d_w, int *d_h);
+void mp_image_params_set_dsize(struct mp_image_params *p, int d_w, int d_h);
+
 void mp_image_set_params(struct mp_image *image,
                          const struct mp_image_params *params);