options: add --video-scale-x/y

Requested.

Fixes: #6303

4 files changed, 18 insertions, 4 deletions

diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 95cd12a7b3..769db4d837 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -1467,6 +1467,15 @@ Video
 
     This option is disabled if the ``--no-keepaspect`` option is used.
 
+``--video-scale-x=<value>``, ``--video-scale-y=<value>``
+    Multiply the video display size with the given value (default: 1.0). If a
+    non-default value is used, this will be different from the window size, so
+    video will be either cut off, or black bars are added.
+
+    This value is multiplied with the value derived from ``--video-zoom`` and
+    the normal video aspect aspect ratio. This option is disabled if the
+    ``--no-keepaspect`` option is used.
+
 ``--video-align-x=<-1-1>``, ``--video-align-y=<-1-1>``
     Moves the video rectangle within the black borders, which are usually added
     to pad the video to screen if video and screen aspect ratios are different.
diff --git a/options/options.c b/options/options.c
index 22ae8e77e5..4467c106ba 100644
--- a/options/options.c
+++ b/options/options.c
@@ -136,6 +136,8 @@ static const m_option_t mp_vo_opt_list[] = {
     {"video-pan-y", OPT_FLOAT(pan_y), M_RANGE(-3.0, 3.0)},
     {"video-align-x", OPT_FLOAT(align_x), M_RANGE(-1.0, 1.0)},
     {"video-align-y", OPT_FLOAT(align_y), M_RANGE(-1.0, 1.0)},
+    {"video-scale-x", OPT_FLOAT(scale_x), M_RANGE(0, 10000.0)},
+    {"video-scale-y", OPT_FLOAT(scale_y), M_RANGE(0, 10000.0)},
     {"video-margin-ratio-left", OPT_FLOAT(margin_x[0]), M_RANGE(0.0, 1.0)},
     {"video-margin-ratio-right", OPT_FLOAT(margin_x[1]), M_RANGE(0.0, 1.0)},
     {"video-margin-ratio-top", OPT_FLOAT(margin_y[0]), M_RANGE(0.0, 1.0)},
@@ -177,6 +179,8 @@ const struct m_sub_options vo_sub_opts = {
         .screen_id = -1,
         .fsscreen_id = -1,
         .panscan = 0.0f,
+        .scale_x = 1.0f,
+        .scale_y = 1.0f,
         .keepaspect = 1,
         .keepaspect_window = 1,
         .hidpi_window_scale = 1,
diff --git a/options/options.h b/options/options.h
index 92e0d7c129..45d0747358 100644
--- a/options/options.h
+++ b/options/options.h
@@ -31,6 +31,7 @@ typedef struct mp_vo_opts {
     float zoom;
     float pan_x, pan_y;
     float align_x, align_y;
+    float scale_x, scale_y;
     float margin_x[2];
     float margin_y[2];
     int unscaled;
diff --git a/video/out/aspect.c b/video/out/aspect.c
index 7307ed6b34..c07fdce84a 100644
--- a/video/out/aspect.c
+++ b/video/out/aspect.c
@@ -77,12 +77,12 @@ static void clamp_size(int size, int *start, int *end)
 
 static void src_dst_split_scaling(int src_size, int dst_size,
                                   int scaled_src_size,
-                                  float zoom, float align, float pan,
+                                  float zoom, float align, float pan, float scale,
                                   int *src_start, int *src_end,
                                   int *dst_start, int *dst_end,
                                   int *osd_margin_a, int *osd_margin_b)
 {
-    scaled_src_size *= powf(2, zoom);
+    scaled_src_size *= powf(2, zoom) * scale;
     align = (align + 1) / 2;
 
     *src_start = 0;
@@ -168,11 +168,11 @@ void mp_get_src_dst_rects(struct mp_log *log, struct mp_vo_opts *opts,
                             vid_window_w, vid_window_h, monitor_par,
                             &scaled_width, &scaled_height);
         src_dst_split_scaling(src_w, vid_window_w, scaled_width,
-                              opts->zoom, opts->align_x, opts->pan_x,
+                              opts->zoom, opts->align_x, opts->pan_x, opts->scale_x,
                               &src.x0, &src.x1, &dst.x0, &dst.x1,
                               &osd.ml, &osd.mr);
         src_dst_split_scaling(src_h, vid_window_h, scaled_height,
-                              opts->zoom, opts->align_y, opts->pan_y,
+                              opts->zoom, opts->align_y, opts->pan_y, opts->scale_y,
                               &src.y0, &src.y1, &dst.y0, &dst.y1,
                               &osd.mt, &osd.mb);
     }