diff --git a/libswscale/input.c b/libswscale/input.c
index 304466bd99..9f2ef72894 100644
--- a/libswscale/input.c
+++ b/libswscale/input.c
@@ -671,6 +671,19 @@ static av_always_inline void planar_rgb16_to_y(uint8_t *_dst, const uint8_t *_sr
     }
 }
 
+static av_always_inline void planar_rgb16_to_a(uint8_t *_dst, const uint8_t *_src[4],
+                                               int width, int bpc, int is_be)
+{
+    int i;
+    const uint16_t **src = (const uint16_t **)_src;
+    uint16_t *dst        = (uint16_t *)_dst;
+    int shift = bpc < 15 ? bpc : 14;
+
+    for (i = 0; i < width; i++) {
+        dst[i] = rdpx(src[3] + i) << (14 - shift);
+    }
+}
+
 static void planar_rgb9le_to_y(uint8_t *dst, const uint8_t *src[4], int w)
 {
     planar_rgb16_to_y(dst, src, w, 9, 0);
@@ -696,21 +709,41 @@ static void planar_rgb12le_to_y(uint8_t *dst, const uint8_t *src[4], int w)
     planar_rgb16_to_y(dst, src, w, 12, 0);
 }
 
+static void planar_rgb12le_to_a(uint8_t *dst, const uint8_t *src[4], int w)
+{
+    planar_rgb16_to_a(dst, src, w, 12, 0);
+}
+
 static void planar_rgb12be_to_y(uint8_t *dst, const uint8_t *src[4], int w)
 {
     planar_rgb16_to_y(dst, src, w, 12, 1);
 }
 
+static void planar_rgb12be_to_a(uint8_t *dst, const uint8_t *src[4], int w)
+{
+    planar_rgb16_to_a(dst, src, w, 12, 1);
+}
+
 static void planar_rgb16le_to_y(uint8_t *dst, const uint8_t *src[4], int w)
 {
     planar_rgb16_to_y(dst, src, w, 16, 0);
 }
 
+static void planar_rgb16le_to_a(uint8_t *dst, const uint8_t *src[4], int w)
+{
+    planar_rgb16_to_a(dst, src, w, 16, 0);
+}
+
 static void planar_rgb16be_to_y(uint8_t *dst, const uint8_t *src[4], int w)
 {
     planar_rgb16_to_y(dst, src, w, 16, 1);
 }
 
+static void planar_rgb16be_to_a(uint8_t *dst, const uint8_t *src[4], int w)
+{
+    planar_rgb16_to_a(dst, src, w, 16, 1);
+}
+
 static av_always_inline void planar_rgb16_to_uv(uint8_t *_dstU, uint8_t *_dstV,
                                                 const uint8_t *_src[4], int width,
                                                 int bpc, int is_be)
@@ -1044,10 +1077,12 @@ av_cold void ff_sws_init_input_funcs(SwsContext *c)
         c->readLumPlanar = planar_rgb10le_to_y;
         break;
     case AV_PIX_FMT_GBRAP12LE:
+        c->readAlpPlanar = planar_rgb12le_to_a;
     case AV_PIX_FMT_GBRP12LE:
         c->readLumPlanar = planar_rgb12le_to_y;
         break;
     case AV_PIX_FMT_GBRAP16LE:
+        c->readAlpPlanar = planar_rgb16le_to_a;
     case AV_PIX_FMT_GBRP16LE:
         c->readLumPlanar = planar_rgb16le_to_y;
         break;
@@ -1058,10 +1093,12 @@ av_cold void ff_sws_init_input_funcs(SwsContext *c)
         c->readLumPlanar = planar_rgb10be_to_y;
         break;
     case AV_PIX_FMT_GBRAP12BE:
+        c->readAlpPlanar = planar_rgb12be_to_a;
     case AV_PIX_FMT_GBRP12BE:
         c->readLumPlanar = planar_rgb12be_to_y;
         break;
     case AV_PIX_FMT_GBRAP16BE:
+        c->readAlpPlanar = planar_rgb16be_to_a;
     case AV_PIX_FMT_GBRP16BE:
         c->readLumPlanar = planar_rgb16be_to_y;
         break;
diff --git a/tests/ref/fate/filter-pixfmts-scale b/tests/ref/fate/filter-pixfmts-scale
index 142b6371aa..97f29bed69 100644
--- a/tests/ref/fate/filter-pixfmts-scale
+++ b/tests/ref/fate/filter-pixfmts-scale
@@ -13,8 +13,8 @@ bgr565le            34438643c183ff1748cf7d71453f981c
 bgr8                e731ba3dbec294e1daa7313e08e88034
 bgra                6e1f417ae41636f631de1cfe39ce1778
 gbrap               eefdbfd1426765ce5e9790022533db0d
-gbrap12be           c676f72b634c77b08a00ab12dc21c5dc
-gbrap12le           90ca5271960dc1ebd6ebe14189223e36
+gbrap12be           af4acb3ad0a6630f6ec4534e4d2e869a
+gbrap12le           fb66da21243e922b4e12ca05d8242c42
 gbrp                5d14768d2ab6cbf3879966b5d5c6befb
 gbrp10be            4192c246f4a52ec7a37919665190cce9
 gbrp10le            170189b2c2dd46f31165d8fa6cadef0a