video: add unscaled mode with --video-unscaled

5 files changed, 32 insertions, 3 deletions

diff --git a/DOCS/man/en/options.rst b/DOCS/man/en/options.rst
index 61fa750b76..5c33e325f1 100644
--- a/DOCS/man/en/options.rst
+++ b/DOCS/man/en/options.rst
@@ -2498,6 +2498,18 @@
 
     This option is disabled if the ``--no-keepaspect`` option is used.
 
+``--video-unscaled=<value>``
+    Disable scaling of the video. If the window is larger than the video,
+    black bars are added. Otherwise, the video is cropped. The video still
+    can be influenced by the other ``--video-...`` options. (If the
+    ``--video-zoom`` option is set to a value other than ``1``, scaling is
+    enabled, but the video isn't automatically scaled to the window size.)
+
+    Note that the scaler algorithm may still be used, even if the video isn't
+    scaled. For example, this can influence chroma conversion.
+
+    This option is disabled if the ``--no-keepaspect`` option is used.
+
 ``--video-zoom=<value>``
     Adjust the video display scale factor by the given value. The unit is in
     fractions of original video size.
diff --git a/mpvcore/command.c b/mpvcore/command.c
index db4b2a7a9c..cfb3c3c60a 100644
--- a/mpvcore/command.c
+++ b/mpvcore/command.c
@@ -1782,6 +1782,7 @@ static const m_option_t mp_properties[] = {
     M_OPTION_PROPERTY_CUSTOM("video-align-y", panscan_property_helper),
     M_OPTION_PROPERTY_CUSTOM("video-pan-x", panscan_property_helper),
     M_OPTION_PROPERTY_CUSTOM("video-pan-y", panscan_property_helper),
+    M_OPTION_PROPERTY_CUSTOM("video-unscaled", panscan_property_helper),
     { "video-format", mp_property_video_format, CONF_TYPE_STRING,
       0, 0, 0, NULL },
     { "video-codec", mp_property_video_codec, CONF_TYPE_STRING,
diff --git a/mpvcore/options.c b/mpvcore/options.c
index e508262378..62bbfc0101 100644
--- a/mpvcore/options.c
+++ b/mpvcore/options.c
@@ -587,6 +587,7 @@ const m_option_t mp_opts[] = {
     OPT_FLOATRANGE("video-pan-y", vo.pan_y, 0, -3.0, 3.0),
     OPT_FLOATRANGE("video-align-x", vo.align_x, 0, -1.0, 1.0),
     OPT_FLOATRANGE("video-align-y", vo.align_y, 0, -1.0, 1.0),
+    OPT_FLAG("video-unscaled", vo.unscaled, 0),
     OPT_FLAG("force-rgba-osd-rendering", force_rgba_osd, 0),
     OPT_CHOICE("colormatrix", requested_colorspace, 0,
                ({"auto", MP_CSP_AUTO},
diff --git a/mpvcore/options.h b/mpvcore/options.h
index 033d3c89c6..cac2630040 100644
--- a/mpvcore/options.h
+++ b/mpvcore/options.h
@@ -22,6 +22,7 @@ typedef struct mp_vo_opts {
     float zoom;
     float pan_x, pan_y;
     float align_x, align_y;
+    int unscaled;
 
     struct m_geometry geometry;
     struct m_geometry autofit;
diff --git a/video/out/vo.c b/video/out/vo.c
index d134163141..aa027fc349 100644
--- a/video/out/vo.c
+++ b/video/out/vo.c
@@ -490,12 +490,15 @@ static void clamp_size(int size, int *start, int *end)
 #define VID_SRC_ROUND_UP(x) (((x) + 1) & ~1)
 
 static void src_dst_split_scaling(int src_size, int dst_size,
-                                  int scaled_src_size,
+                                  int scaled_src_size, bool unscaled,
                                   float zoom, float align, float pan,
                                   int *src_start, int *src_end,
                                   int *dst_start, int *dst_end,
                                   int *osd_margin_a, int *osd_margin_b)
 {
+    if (unscaled)
+        scaled_src_size = src_size;
+
     scaled_src_size += zoom * src_size;
     align = (align + 1) / 2;
 
@@ -522,6 +525,17 @@ static void src_dst_split_scaling(int src_size, int dst_size,
         *dst_end = dst_size;
     }
 
+    if (unscaled && zoom == 1.0) {
+        // Force unscaled by reducing the range for src or dst
+        int src_s = *src_end - *src_start;
+        int dst_s = *dst_end - *dst_start;
+        if (src_s > dst_s) {
+            *src_end = *src_start + dst_s;
+        } else if (src_s < dst_s) {
+            *dst_end = *dst_start + src_s;
+        }
+    }
+
     // For sanity: avoid bothering VOs with corner cases
     clamp_size(src_size, src_start, src_end);
     clamp_size(dst_size, dst_start, dst_end);
@@ -549,11 +563,11 @@ void vo_get_src_dst_rects(struct vo *vo, struct mp_rect *out_src,
     if (opts->keepaspect) {
         int scaled_width, scaled_height;
         aspect_calc_panscan(vo, &scaled_width, &scaled_height);
-        src_dst_split_scaling(src_w, vo->dwidth, scaled_width,
+        src_dst_split_scaling(src_w, vo->dwidth, scaled_width, opts->unscaled,
                               opts->zoom, opts->align_x, opts->pan_x,
                               &src.x0, &src.x1, &dst.x0, &dst.x1,
                               &osd.ml, &osd.mr);
-        src_dst_split_scaling(src_h, vo->dheight, scaled_height,
+        src_dst_split_scaling(src_h, vo->dheight, scaled_height, opts->unscaled,
                               opts->zoom, opts->align_y, opts->pan_y,
                               &src.y0, &src.y1, &dst.y0, &dst.y1,
                               &osd.mt, &osd.mb);