img_format: add some mpv-only helper formats

Utterly useless, but the intention is to make dealing with corner case
pixel formats (forced upon us by FFmpeg, very rarely) less of a pain.
The zimg wrapper will use them. (It already supports these formats
automatically, but it will help with its internals.)

Y1 is considered RGB, even though gray formats are generally treated as
YUV for various reasons. mpv will default all YUV formats to limited
range internally, which makes no sense for a 1 bit format, so this is a
problem. I wanted to avoid that mp_image_params_guess_csp() (which
applies the default) explicitly checks for an image format, so although
a bit janky, this seems to be a good solution, especially because I
really don't give a shit about these formats, other than having to
handle them. It's notable that AV_PIX_FMT_MONOBLACK (also 1 bit gray,
just packed) already explicitly marked itself as RGB.

2 files changed, 34 insertions, 0 deletions

diff --git a/video/img_format.c b/video/img_format.c
index ed194ef751..6379dd41d1 100644
--- a/video/img_format.c
+++ b/video/img_format.c
@@ -39,6 +39,14 @@ struct mp_imgfmt_entry {
     enum mp_component_type ctype;
 };
 
+#define FRINGE_GBRP(def, dname, bits)                                       \
+    [def - IMGFMT_CUST_BASE] = {                                            \
+        .name = dname,                                                      \
+        .reg_desc = { .component_type = MP_COMPONENT_TYPE_UINT,             \
+                      .component_size = 1, .component_pad = bits - 8,       \
+                      .num_planes = 3, .forced_csp = MP_CSP_RGB,            \
+                      .planes = { {1, {2}}, {1, {3}}, {1, {1}} }, }, }
+
 static const struct mp_imgfmt_entry mp_imgfmt_list[] = {
     // not in ffmpeg
     [IMGFMT_VDPAU_OUTPUT - IMGFMT_CUST_BASE] = {
@@ -85,6 +93,23 @@ static const struct mp_imgfmt_entry mp_imgfmt_list[] = {
             .planes = { {1, {1}}, {1, {4}} },
         },
     },
+    [IMGFMT_Y1 - IMGFMT_CUST_BASE] = {
+        .name = "y1",
+        .reg_desc = {
+            .component_type = MP_COMPONENT_TYPE_UINT,
+            .component_size = 1,
+            .component_pad = -7,
+            .num_planes = 1,
+            .forced_csp = MP_CSP_RGB,
+            .planes = { {1, {1}} },
+        },
+    },
+    FRINGE_GBRP(IMGFMT_GBRP1, "gbrp1", 1),
+    FRINGE_GBRP(IMGFMT_GBRP2, "gbrp2", 2),
+    FRINGE_GBRP(IMGFMT_GBRP3, "gbrp3", 3),
+    FRINGE_GBRP(IMGFMT_GBRP4, "gbrp4", 4),
+    FRINGE_GBRP(IMGFMT_GBRP5, "gbrp5", 5),
+    FRINGE_GBRP(IMGFMT_GBRP6, "gbrp6", 6),
     // in FFmpeg, but FFmpeg names have an annoying "_vld" suffix
     [IMGFMT_VIDEOTOOLBOX - IMGFMT_CUST_BASE] = {
         .name = "videotoolbox",
diff --git a/video/img_format.h b/video/img_format.h
index 2bd448899b..f422019dec 100644
--- a/video/img_format.h
+++ b/video/img_format.h
@@ -214,6 +214,15 @@ enum mp_imgfmt {
     // Accessed with bit-shifts, uint32_t units.
     IMGFMT_RGB30,               // 2pad 10r 10g 10b (MSG to LSB)
 
+    // Fringe formats for fringe RGB format repacking.
+    IMGFMT_Y1,      // gray with 1 bit per pixel
+    IMGFMT_GBRP1,   // planar RGB with N bits per color component
+    IMGFMT_GBRP2,
+    IMGFMT_GBRP3,
+    IMGFMT_GBRP4,
+    IMGFMT_GBRP5,
+    IMGFMT_GBRP6,
+
     // Hardware accelerated formats (again).
     IMGFMT_VDPAU_OUTPUT,    // VdpOutputSurface
     IMGFMT_VAAPI,