diff --git a/libavcodec/x86/h264_deblock.asm b/libavcodec/x86/h264_deblock.asm
index 5151f3c9cd..8f80863fc5 100644
--- a/libavcodec/x86/h264_deblock.asm
+++ b/libavcodec/x86/h264_deblock.asm
@@ -864,7 +864,50 @@ ff_chroma_inter_body_mmxext:
     DEBLOCK_P0_Q0
     ret
 
+%define t5 r4
+%define t6 r5
 
+cglobal deblock_h_chroma422_8, 5, 6, 0, 0-(1+ARCH_X86_64*2)*mmsize
+    %if ARCH_X86_64
+        %define buf0 [rsp+16]
+        %define buf1 [rsp+8]
+    %else
+        %define buf0 r0m
+        %define buf1 r2m
+    %endif
+
+    movd m6, [r4]
+    punpcklbw m6, m6
+    movq [rsp], m6
+    CHROMA_H_START
+
+    TRANSPOSE4x8B_LOAD PASS8ROWS(t5, r0, r1, t6)
+    movq buf0, m0
+    movq buf1, m3
+    LOAD_MASK r2d, r3d
+    movd m6, [rsp]
+    punpcklwd m6, m6
+    pand m7, m6
+    DEBLOCK_P0_Q0
+    movq m0, buf0
+    movq m3, buf1
+    TRANSPOSE8x4B_STORE PASS8ROWS(t5, r0, r1, t6)
+
+    lea r0, [r0+r1*8]
+    lea t5, [t5+r1*8]
+
+    TRANSPOSE4x8B_LOAD PASS8ROWS(t5, r0, r1, t6)
+    movq buf0, m0
+    movq buf1, m3
+    LOAD_MASK r2d, r3d
+    movd m6, [rsp+4]
+    punpcklwd m6, m6
+    pand m7, m6
+    DEBLOCK_P0_Q0
+    movq m0, buf0
+    movq m3, buf1
+    TRANSPOSE8x4B_STORE PASS8ROWS(t5, r0, r1, t6)
+RET
 
 ; in: %1=p0 %2=p1 %3=q1
 ; out: p0 = (p0 + q1 + 2*p1 + 2) >> 2
@@ -877,9 +920,6 @@ ff_chroma_inter_body_mmxext:
     pavgb   %1, %2             ; dst = avg(p1, avg(p0,q1) - ((p0^q1)&1))
 %endmacro
 
-%define t5 r4
-%define t6 r5
-
 ;------------------------------------------------------------------------------
 ; void ff_deblock_v_chroma_intra(uint8_t *pix, int stride, int alpha, int beta)
 ;------------------------------------------------------------------------------
diff --git a/libavcodec/x86/h264dsp_init.c b/libavcodec/x86/h264dsp_init.c
index 35db20014a..c8cd0650c7 100644
--- a/libavcodec/x86/h264dsp_init.c
+++ b/libavcodec/x86/h264dsp_init.c
@@ -129,6 +129,8 @@ LF_IFUNC(v, chroma_intra, depth, avx)
 LF_FUNCS(uint8_t,   8)
 LF_FUNCS(uint16_t, 10)
 
+void ff_deblock_h_chroma422_8_mmxext(uint8_t *pix, int stride, int alpha, int beta, int8_t *tc0);
+
 #if ARCH_X86_32 && HAVE_MMXEXT_EXTERNAL
 LF_FUNC(v8, luma, 8, mmxext)
 static void deblock_v_luma_8_mmxext(uint8_t *pix, int stride, int alpha,
@@ -245,6 +247,8 @@ av_cold void ff_h264dsp_init_x86(H264DSPContext *c, const int bit_depth,
             if (chroma_format_idc <= 1) {
                 c->h264_h_loop_filter_chroma       = ff_deblock_h_chroma_8_mmxext;
                 c->h264_h_loop_filter_chroma_intra = ff_deblock_h_chroma_intra_8_mmxext;
+            } else {
+                c->h264_h_loop_filter_chroma = ff_deblock_h_chroma422_8_mmxext;
             }
 #if ARCH_X86_32 && HAVE_MMXEXT_EXTERNAL
             c->h264_v_loop_filter_luma       = deblock_v_luma_8_mmxext;