shithub: dav1d

Download patch

ref: 556890be42d8affef280188c1a5d22cf299b2197
parent: 6d363223dc979c393217c86eda54848531d69b9e
author: Ronald S. Bultje <rsbultje@gmail.com>
date: Tue Sep 10 07:00:54 EDT 2019

AVX2 for chroma 4:2:0 film grain reconstruction

fguv_32x32xn_8bpc_420_csfl0_c: 8945.4
fguv_32x32xn_8bpc_420_csfl0_avx2: 1001.6
fguv_32x32xn_8bpc_420_csfl1_c: 6363.4
fguv_32x32xn_8bpc_420_csfl1_avx2: 1299.5

--- a/src/fg_apply_tmpl.c
+++ b/src/fg_apply_tmpl.c
@@ -136,6 +136,8 @@
     // Synthesize grain for the affected planes
     const int rows = (out->p.h + 31) >> 5;
     const int ss_y = in->p.layout == DAV1D_PIXEL_LAYOUT_I420;
+    const int ss_x = in->p.layout != DAV1D_PIXEL_LAYOUT_I444;
+    const int cpw = (out->p.w + ss_x) >> ss_x;
     const int is_id = out->seq_hdr->mtrx == DAV1D_MC_IDENTITY;
     for (int row = 0; row < rows; row++) {
         const pixel *const luma_src =
@@ -144,7 +146,7 @@
         if (data->num_y_points) {
             const int bh = imin(out->p.h - row * BLOCK_SIZE, BLOCK_SIZE);
             dsp->fgy_32x32xn(((pixel *) out->data[0]) + row * BLOCK_SIZE * PXSTRIDE(out->stride[0]),
-                             luma_src, out->stride[0], &out->frame_hdr->film_grain.data,
+                             luma_src, out->stride[0], data,
                              out->p.w, scaling[0], grain_lut[0], bh, row HIGHBD_TAIL_SUFFIX);
         }
 
@@ -154,22 +156,19 @@
             for (int pl = 0; pl < 2; pl++)
                 dsp->fguv_32x32xn[in->p.layout - 1](((pixel *) out->data[1 + pl]) + uv_off,
                                                     ((const pixel *) in->data[1 + pl]) + uv_off,
-                                                    in->stride[1], luma_src,
-                                                    in->stride[0], out->p.w, bh,
-                                                    &out->frame_hdr->film_grain.data,
-                                                    grain_lut[1 + pl], scaling[0],
-                                                    pl, row, is_id HIGHBD_TAIL_SUFFIX);
+                                                    in->stride[1], data, cpw,
+                                                    scaling[0], grain_lut[1 + pl],
+                                                    bh, row, luma_src, in->stride[0],
+                                                    pl, is_id HIGHBD_TAIL_SUFFIX);
         } else {
             for (int pl = 0; pl < 2; pl++)
                 if (data->num_uv_points[pl])
                     dsp->fguv_32x32xn[in->p.layout - 1](((pixel *) out->data[1 + pl]) + uv_off,
                                                         ((const pixel *) in->data[1 + pl]) + uv_off,
-                                                        in->stride[1], luma_src,
-                                                        in->stride[0], out->p.w, bh,
-                                                        &out->frame_hdr->film_grain.data,
-                                                        grain_lut[1 + pl],
-                                                        scaling[1 + pl], pl, row, is_id
-                                                        HIGHBD_TAIL_SUFFIX);
+                                                        in->stride[1], data, cpw,
+                                                        scaling[1 + pl], grain_lut[1 + pl],
+                                                        bh, row, luma_src, in->stride[0],
+                                                        pl, is_id HIGHBD_TAIL_SUFFIX);
         }
     }
 }
--- a/src/film_grain.h
+++ b/src/film_grain.h
@@ -64,11 +64,11 @@
 
 #define decl_fguv_32x32xn_fn(name) \
 void (name)(pixel *dst_row, const pixel *src_row, ptrdiff_t stride, \
-            const pixel *luma_row, ptrdiff_t luma_stride, int pw, int bh, \
-            const Dav1dFilmGrainData *data, \
-            const entry grain_lut[][GRAIN_WIDTH], \
+            const Dav1dFilmGrainData *data, int pw, \
             const uint8_t scaling[SCALING_SIZE], \
-            int uv_pl, int row_num, int is_id HIGHBD_DECL_SUFFIX)
+            const entry grain_lut[][GRAIN_WIDTH], int bh, int row_num, \
+            const pixel *luma_row, ptrdiff_t luma_stride, \
+            int uv_pl, int is_id HIGHBD_DECL_SUFFIX)
 typedef decl_fguv_32x32xn_fn(*fguv_32x32xn_fn);
 
 typedef struct Dav1dFilmGrainDSPContext {
--- a/src/film_grain_tmpl.c
+++ b/src/film_grain_tmpl.c
@@ -281,12 +281,11 @@
 
 static NOINLINE void
 fguv_32x32xn_c(pixel *const dst_row, const pixel *const src_row,
-               const ptrdiff_t stride, const pixel *const luma_row,
-               const ptrdiff_t luma_stride, const int pw, const int bh,
-               const Dav1dFilmGrainData *const data,
-               const entry grain_lut[][GRAIN_WIDTH],
-               const uint8_t scaling[SCALING_SIZE],
-               const int uv, const int row_num, const int is_id,
+               const ptrdiff_t stride, const Dav1dFilmGrainData *const data,
+               const int pw, const uint8_t scaling[SCALING_SIZE],
+               const entry grain_lut[][GRAIN_WIDTH], const int bh,
+               const int row_num, const pixel *const luma_row,
+               const ptrdiff_t luma_stride, const int uv, const int is_id,
                const int sx, const int sy HIGHBD_DECL_SUFFIX)
 {
     const int rows = 1 + (data->overlap_flag && row_num > 0);
@@ -320,8 +319,8 @@
     int offsets[2 /* col offset */][2 /* row offset */];
 
     // process this row in BLOCK_SIZE^2 blocks (subsampled)
-    for (int bx = 0; bx < (pw + sx) >> sx; bx += BLOCK_SIZE >> sx) {
-        const int bw = (imin(BLOCK_SIZE, pw - (bx << sx)) + sx) >> sx;
+    for (int bx = 0; bx < pw; bx += BLOCK_SIZE >> sx) {
+        const int bw = imin(BLOCK_SIZE >> sx, pw - bx);
         if (data->overlap_flag && bx) {
             // shift previous offsets left
             for (int i = 0; i < rows; i++)
@@ -412,8 +411,8 @@
 
 #define fguv_ss_fn(nm, ss_x, ss_y) \
 static decl_fguv_32x32xn_fn(fguv_32x32xn_##nm##_c) { \
-    fguv_32x32xn_c(dst_row, src_row, stride, luma_row, luma_stride, pw, bh, \
-                   data, grain_lut, scaling, uv_pl, row_num, is_id, ss_x, ss_y \
+    fguv_32x32xn_c(dst_row, src_row, stride, data, pw, scaling, grain_lut, bh, \
+                   row_num, luma_row, luma_stride, uv_pl, is_id, ss_x, ss_y \
                    HIGHBD_TAIL_SUFFIX); \
 }
 
--- a/src/x86/film_grain.asm
+++ b/src/x86/film_grain.asm
@@ -28,19 +28,20 @@
 %if ARCH_X86_64
 
 SECTION_RODATA
+pw_1024: times 16 dw 1024
 pb_mask: db 0, 0x80, 0x80, 0, 0x80, 0, 0, 0x80, 0x80, 0, 0, 0x80, 0, 0x80, 0x80, 0
 rnd_next_upperbit_mask: dw 0x100B, 0x2016, 0x402C, 0x8058
 byte_blend: db 0, 0, 0, 0xff, 0, 0, 0, 0
-pw_1024: times 2 dw 1024
 pd_m65536: dd ~0xffff
+pb_23_22: times 2 db 23, 22
+pb_1: times 4 db 1
 hmul_bits: dw 32768, 16384, 8192, 4096
 round: dw 2048, 1024, 512
 mul_bits: dw 256, 128, 64, 32, 16
 round_vals: dw 32, 64, 128, 256, 512
-max: dw 255, 235
+max: dw 255, 240, 235
 min: dw 0, 16
 pb_27_17_17_27: db 27, 17, 17, 27
-pb_1: db 1
 
 %macro JMP_TABLE 1-*
     %xdefine %1_table %%table
@@ -417,7 +418,7 @@
 %define base r8-pb_mask
     vpbroadcastw    m11, [base+mul_bits+r7*2-14]
     mov             r7d, [fg_dataq+FGData.clip_to_restricted_range]
-    vpbroadcastw    m12, [base+max+r7*2]
+    vpbroadcastw    m12, [base+max+r7*4]
     vpbroadcastw    m13, [base+min+r7*2]
 
     DEFINE_ARGS dst, src, stride, fg_data, w, scaling, grain_lut, unused, sby, see, overlap
@@ -435,7 +436,6 @@
     movzx          seed, seew
     xor            seed, [fg_dataq+FGData.seed]
 
-
     DEFINE_ARGS dst, src, stride, src_bak, w, scaling, grain_lut, \
                 unused1, unused2, see, overlap
 
@@ -816,7 +816,7 @@
 
     ; scaling[src]
     pcmpeqw          m3, m3
-; FIXME it would be nice to have another register here to do 2 vpgatherdd's in parallel
+    ; FIXME it would be nice to have another register here to do 2 vpgatherdd's in parallel
     vpgatherdd       m9, [scalingq+m4], m3
     pcmpeqw          m3, m3
     vpgatherdd       m4, [scalingq+m5], m3
@@ -896,5 +896,687 @@
 
 .end_hv:
     RET
+
+cglobal fguv_32x32xn_i420, 6, 15, 16, dst, src, stride, fg_data, w, scaling, \
+                                      grain_lut, h, sby, luma, lstride, uv_pl, is_id
+    pcmpeqw         m10, m10
+    psrld           m10, 24
+    mov             r7d, [fg_dataq+FGData.scaling_shift]
+    lea              r8, [pb_mask]
+%define base r8-pb_mask
+    vpbroadcastw    m11, [base+mul_bits+r7*2-14]
+    mov             r7d, [fg_dataq+FGData.clip_to_restricted_range]
+    mov             r9d, dword is_idm
+    vpbroadcastw    m13, [base+min+r7*2]
+    shlx            r7d, r7d, r9d
+    vpbroadcastw    m12, [base+max+r7*2]
+
+    cmp byte [fg_dataq+FGData.chroma_scaling_from_luma], 0
+    jne .csfl
+
+%macro FGUV_32x32xN_LOOP 1 ; not-csfl
+    DEFINE_ARGS dst, src, stride, fg_data, w, scaling, grain_lut, unused, sby, see, overlap
+
+%if %1
+    mov             r7d, dword r11m
+    vpbroadcastb     m0, [fg_dataq+FGData.uv_mult+r7*4]
+    vpbroadcastb     m1, [fg_dataq+FGData.uv_luma_mult+r7*4]
+    punpcklbw       m14, m1, m0
+    vpbroadcastw    m15, [fg_dataq+FGData.uv_offset+r7*4]
+%else
+    vpbroadcastd    m14, [pw_1024]
+    vpbroadcastd    m15, [pb_23_22]
+%endif
+
+    mov        overlapd, [fg_dataq+FGData.overlap_flag]
+    movifnidn      sbyd, sbym
+    test           sbyd, sbyd
+    setnz           r7b
+    test            r7b, overlapb
+    jnz %%vertical_overlap
+
+    imul           seed, sbyd, (173 << 24) | 37
+    add            seed, (105 << 24) | 178
+    rol            seed, 8
+    movzx          seed, seew
+    xor            seed, [fg_dataq+FGData.seed]
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                unused2, unused3, see, overlap, unused4, unused5, lstride
+
+    mov           lumaq, r9mp
+    lea             r12, [srcq+wq]
+    lea             r13, [dstq+wq]
+    lea             r14, [lumaq+wq*2]
+    mov           r11mp, r12
+    mov           r12mp, r13
+    mov        lstrideq, r10mp
+    neg              wq
+
+%%loop_x:
+    mov             r6d, seed
+    or             seed, 0xEFF4
+    shr             r6d, 1
+    test           seeb, seeh
+    lea            seed, [r6+0x8000]
+    cmovp          seed, r6d               ; updated seed
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                offx, offy, see, overlap, unused1, unused2, lstride
+
+    mov           offxd, seed
+    rorx          offyd, seed, 8
+    shr           offxd, 12
+    and           offyd, 0xf
+    imul          offyd, 82
+    lea           offyq, [offyq+offxq+498]  ; offy*stride+offx
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                h, offxy, see, overlap, unused1, unused2, lstride
+
+    mov              hd, hm
+    mov      grain_lutq, grain_lutmp
+%%loop_y:
+    ; src
+    mova            xm4, [lumaq+lstrideq*0+ 0]
+    mova            xm6, [lumaq+lstrideq*0+16]
+    mova            xm0, [srcq]
+    vpbroadcastd     m7, [pb_1]
+    vinserti128      m4, [lumaq+lstrideq*2 +0], 1
+    vinserti128      m6, [lumaq+lstrideq*2+16], 1
+    vinserti128      m0, [srcq+strideq], 1
+    pxor             m2, m2
+    pmaddubsw        m4, m7
+    pmaddubsw        m6, m7
+    pavgw            m4, m2
+    pavgw            m6, m2
+
+%if %1
+    packuswb         m4, m6                 ; luma
+    punpckhbw        m6, m4, m0
+    punpcklbw        m4, m0                 ; { luma, chroma }
+    pmaddubsw        m6, m14
+    pmaddubsw        m4, m14
+    psraw            m6, 6
+    psraw            m4, 6
+    paddw            m6, m15
+    paddw            m4, m15
+    packuswb         m4, m6                 ; pack+unpack = clip
+    punpckhbw        m6, m4, m2
+    punpcklbw        m4, m2
+%endif
+
+    punpckhwd        m5, m4, m2
+    punpcklwd        m4, m2
+    punpckhwd        m7, m6, m2
+    punpcklwd        m6, m2                 ; m4-7: luma_src as dword
+
+    ; scaling[luma_src]
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m8, [scalingq+m4], m3
+    vpgatherdd       m4, [scalingq+m5], m9
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m5, [scalingq+m6], m3
+    vpgatherdd       m6, [scalingq+m7], m9
+    pand             m8, m10
+    pand             m4, m10
+    pand             m5, m10
+    pand             m6, m10
+    packusdw         m8, m4
+    packusdw         m5, m6
+
+    ; unpack chroma_source
+    punpckhbw        m1, m0, m2
+    punpcklbw        m0, m2                 ; m0-1: src as word
+
+    ; grain = grain_lut[offy+y][offx+x]
+    movu            xm3, [grain_lutq+offxyq+ 0]
+    vinserti128      m3, [grain_lutq+offxyq+82], 1
+    pcmpgtb          m7, m2, m3
+    punpcklbw        m2, m3, m7
+    punpckhbw        m3, m7
+
+    ; noise = round2(scaling[luma_src] * grain, scaling_shift)
+    pmullw           m2, m8
+    pmullw           m3, m5
+    pmulhrsw         m2, m11
+    pmulhrsw         m3, m11
+
+    ; dst = clip_pixel(src, noise)
+    paddw            m0, m2
+    paddw            m1, m3
+    pmaxsw           m0, m13
+    pmaxsw           m1, m13
+    pminsw           m0, m12
+    pminsw           m1, m12
+    packuswb         m0, m1
+    mova         [dstq], xm0
+    vextracti128 [dstq+strideq], m0, 1
+
+    lea            srcq, [srcq+strideq*2]
+    lea            dstq, [dstq+strideq*2]
+    lea           lumaq, [lumaq+lstrideq*4]
+    add      grain_lutq, 82*2
+    sub              hb, 2
+    jg %%loop_y
+
+    add              wq, 16
+    jge %%end
+    mov            srcq, r11mp
+    mov            dstq, r12mp
+    lea           lumaq, [r14+wq*2]
+    add            srcq, wq
+    add            dstq, wq
+    test       overlapd, overlapd
+    jz %%loop_x
+
+    ; r8m = sbym
+    cmp       dword r8m, 0
+    jne %%loop_x_hv_overlap
+
+    ; horizontal overlap (without vertical overlap)
+%%loop_x_h_overlap:
+    mov             r6d, seed
+    or             seed, 0xEFF4
+    shr             r6d, 1
+    test           seeb, seeh
+    lea            seed, [r6+0x8000]
+    cmovp          seed, r6d               ; updated seed
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                offx, offy, see, left_offxy, unused1, unused2, lstride
+
+    lea     left_offxyd, [offyd+16]         ; previous column's offy*stride+offx
+    mov           offxd, seed
+    rorx          offyd, seed, 8
+    shr           offxd, 12
+    and           offyd, 0xf
+    imul          offyd, 82
+    lea           offyq, [offyq+offxq+498]  ; offy*stride+offx
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                h, offxy, see, left_offxy, unused1, unused2, lstride
+
+    mov              hd, hm
+    mov      grain_lutq, grain_lutmp
+%%loop_y_h_overlap:
+    ; src
+    mova            xm4, [lumaq+lstrideq*0+ 0]
+    mova            xm6, [lumaq+lstrideq*0+16]
+    mova            xm0, [srcq]
+    vpbroadcastd     m7, [pb_1]
+    vinserti128      m4, [lumaq+lstrideq*2 +0], 1
+    vinserti128      m6, [lumaq+lstrideq*2+16], 1
+    vinserti128      m0, [srcq+strideq], 1
+    pxor             m2, m2
+    pmaddubsw        m4, m7
+    pmaddubsw        m6, m7
+    pavgw            m4, m2
+    pavgw            m6, m2
+
+%if %1
+    packuswb         m4, m6                 ; luma
+    punpckhbw        m6, m4, m0
+    punpcklbw        m4, m0                 ; { luma, chroma }
+    pmaddubsw        m6, m14
+    pmaddubsw        m4, m14
+    psraw            m6, 6
+    psraw            m4, 6
+    paddw            m6, m15
+    paddw            m4, m15
+    packuswb         m4, m6                 ; pack+unpack = clip
+    punpckhbw        m6, m4, m2
+    punpcklbw        m4, m2
+%endif
+
+    punpckhwd        m5, m4, m2
+    punpcklwd        m4, m2
+    punpckhwd        m7, m6, m2
+    punpcklwd        m6, m2                 ; m4-7: luma_src as dword
+
+    ; scaling[luma_src]
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m8, [scalingq+m4], m3
+    vpgatherdd       m4, [scalingq+m5], m9
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m5, [scalingq+m6], m3
+    vpgatherdd       m6, [scalingq+m7], m9
+    pand             m8, m10
+    pand             m4, m10
+    pand             m5, m10
+    pand             m6, m10
+    packusdw         m8, m4
+    packusdw         m5, m6
+
+    ; unpack chroma_source
+    punpckhbw        m1, m0, m2
+    punpcklbw        m0, m2                 ; m0-1: src as word
+
+    ; grain = grain_lut[offy+y][offx+x]
+%if %1
+    vpbroadcastd     m6, [pb_23_22] ; FIXME
+%endif
+    movu            xm3, [grain_lutq+offxyq+ 0]
+    movd            xm4, [grain_lutq+left_offxyq+ 0]
+    vinserti128      m3, [grain_lutq+offxyq+82], 1
+    vinserti128      m4, [grain_lutq+left_offxyq+82], 1
+    punpcklbw        m4, m3
+%if %1
+    pmaddubsw        m4, m6, m4
+    pmulhrsw         m4, [pw_1024]
+%else
+    pmaddubsw        m4, m15, m4
+    pmulhrsw         m4, m14
+%endif
+    packsswb         m4, m4
+    pcmpeqw          m6, m6 ; FIXME
+    psrldq           m6, 15 ; FIXME
+    vpblendvb        m3, m3, m4, m6
+    pcmpgtb          m7, m2, m3
+    punpcklbw        m2, m3, m7
+    punpckhbw        m3, m7
+
+    ; noise = round2(scaling[luma_src] * grain, scaling_shift)
+    pmullw           m2, m8
+    pmullw           m3, m5
+    pmulhrsw         m2, m11
+    pmulhrsw         m3, m11
+
+    ; dst = clip_pixel(src, noise)
+    paddw            m0, m2
+    paddw            m1, m3
+    pmaxsw           m0, m13
+    pmaxsw           m1, m13
+    pminsw           m0, m12
+    pminsw           m1, m12
+    packuswb         m0, m1
+    mova         [dstq], xm0
+    vextracti128 [dstq+strideq], m0, 1
+
+    lea            srcq, [srcq+strideq*2]
+    lea            dstq, [dstq+strideq*2]
+    lea           lumaq, [lumaq+lstrideq*4]
+    add      grain_lutq, 82*2
+    sub              hb, 2
+    jg %%loop_y_h_overlap
+
+    add              wq, 16
+    jge %%end
+    mov            srcq, r11mp
+    mov            dstq, r12mp
+    lea           lumaq, [r14+wq*2]
+    add            srcq, wq
+    add            dstq, wq
+
+    ; r8m = sbym
+    cmp       dword r8m, 0
+    jne %%loop_x_hv_overlap
+    jmp %%loop_x_h_overlap
+
+%%end:
+    RET
+
+%%vertical_overlap:
+    DEFINE_ARGS dst, src, stride, fg_data, w, scaling, grain_lut, unused, \
+                sby, see, overlap, unused1, unused2, lstride
+
+    movzx          sbyd, sbyb
+    imul           seed, [fg_dataq+FGData.seed], 0x00010001
+    imul            r7d, sbyd, 173 * 0x00010001
+    imul           sbyd, 37 * 0x01000100
+    add             r7d, (105 << 16) | 188
+    add            sbyd, (178 << 24) | (141 << 8)
+    and             r7d, 0x00ff00ff
+    and            sbyd, 0xff00ff00
+    xor            seed, r7d
+    xor            seed, sbyd               ; (cur_seed << 16) | top_seed
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                unused1, unused2, see, overlap, unused3, unused4, lstride
+
+    mov           lumaq, r9mp
+    lea             r12, [srcq+wq]
+    lea             r13, [dstq+wq]
+    lea             r14, [lumaq+wq*2]
+    mov           r11mp, r12
+    mov           r12mp, r13
+    mov        lstrideq, r10mp
+    neg              wq
+
+%%loop_x_v_overlap:
+    ; we assume from the block above that bits 8-15 of r7d are zero'ed
+    mov             r6d, seed
+    or             seed, 0xeff4eff4
+    test           seeb, seeh
+    setp            r7b                     ; parity of top_seed
+    shr            seed, 16
+    shl             r7d, 16
+    test           seeb, seeh
+    setp            r7b                     ; parity of cur_seed
+    or              r6d, 0x00010001
+    xor             r7d, r6d
+    rorx           seed, r7d, 1             ; updated (cur_seed << 16) | top_seed
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                offx, offy, see, overlap, top_offxy, unused, lstride
+
+    rorx          offyd, seed, 8
+    rorx          offxd, seed, 12
+    and           offyd, 0xf000f
+    and           offxd, 0xf000f
+    imul          offyd, 82
+    ; offxy=offy*stride+offx, (cur_offxy << 16) | top_offxy
+    lea           offyq, [offyq+offxq+0x10001*498+16*82]
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                h, offxy, see, overlap, top_offxy, unused, lstride
+
+    movzx    top_offxyd, offxyw
+    shr          offxyd, 16
+
+    mov              hd, hm
+    mov      grain_lutq, grain_lutmp
+%%loop_y_v_overlap:
+    ; src
+    mova            xm4, [lumaq+lstrideq*0+ 0]
+    mova            xm6, [lumaq+lstrideq*0+16]
+    mova            xm0, [srcq]
+    vpbroadcastd     m7, [pb_1]
+    vinserti128      m4, [lumaq+lstrideq*2 +0], 1
+    vinserti128      m6, [lumaq+lstrideq*2+16], 1
+    vinserti128      m0, [srcq+strideq], 1
+    pxor             m2, m2
+    pmaddubsw        m4, m7
+    pmaddubsw        m6, m7
+    pavgw            m4, m2
+    pavgw            m6, m2
+
+%if %1
+    packuswb         m4, m6                 ; luma
+    punpckhbw        m6, m4, m0
+    punpcklbw        m4, m0                 ; { luma, chroma }
+    pmaddubsw        m6, m14
+    pmaddubsw        m4, m14
+    psraw            m6, 6
+    psraw            m4, 6
+    paddw            m6, m15
+    paddw            m4, m15
+    packuswb         m4, m6                 ; pack+unpack = clip
+    punpckhbw        m6, m4, m2
+    punpcklbw        m4, m2
+%endif
+
+    punpckhwd        m5, m4, m2
+    punpcklwd        m4, m2
+    punpckhwd        m7, m6, m2
+    punpcklwd        m6, m2                 ; m4-7: luma_src as dword
+
+    ; scaling[luma_src]
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m8, [scalingq+m4], m3
+    vpgatherdd       m4, [scalingq+m5], m9
+    pcmpeqw          m3, m3
+    pcmpeqw          m9, m9
+    vpgatherdd       m5, [scalingq+m6], m3
+    vpgatherdd       m6, [scalingq+m7], m9
+    pand             m8, m10
+    pand             m4, m10
+    pand             m5, m10
+    pand             m6, m10
+    packusdw         m8, m4
+    packusdw         m5, m6
+
+    ; unpack chroma_source
+    punpckhbw        m1, m0, m2
+    punpcklbw        m0, m2                 ; m0-1: src as word
+
+    ; grain = grain_lut[offy+y][offx+x]
+%if %1
+    vpbroadcastd     m6, [pb_23_22]
+%endif
+    movq            xm3, [grain_lutq+offxyq]
+    movq            xm4, [grain_lutq+top_offxyq]
+    vinserti128      m3, [grain_lutq+offxyq+8], 1
+    vinserti128      m4, [grain_lutq+top_offxyq+8], 1
+    punpcklbw        m4, m3
+%if %1
+    pmaddubsw        m4, m6, m4
+    pmulhrsw         m4, [pw_1024]
+%else
+    pmaddubsw        m4, m15, m4
+    pmulhrsw         m4, m14
+%endif
+    packsswb         m4, m4
+    vpermq           m4, m4, q3120
+    ; only interpolate first line, insert second line unmodified
+    vinserti128      m3, m4, [grain_lutq+offxyq+82], 1
+    pcmpgtb          m7, m2, m3
+    punpcklbw        m2, m3, m7
+    punpckhbw        m3, m7
+
+    ; noise = round2(scaling[luma_src] * grain, scaling_shift)
+    pmullw           m2, m8
+    pmullw           m3, m5
+    pmulhrsw         m2, m11
+    pmulhrsw         m3, m11
+
+    ; dst = clip_pixel(src, noise)
+    paddw            m0, m2
+    paddw            m1, m3
+    pmaxsw           m0, m13
+    pmaxsw           m1, m13
+    pminsw           m0, m12
+    pminsw           m1, m12
+    packuswb         m0, m1
+    mova         [dstq], xm0
+    vextracti128 [dstq+strideq], m0, 1
+
+    sub              hb, 2
+    jl %%end_y_v_overlap
+    lea            srcq, [srcq+strideq*2]
+    lea            dstq, [dstq+strideq*2]
+    lea           lumaq, [lumaq+lstrideq*4]
+    add      grain_lutq, 82*2
+    jmp %%loop_y
+
+%%end_y_v_overlap:
+    add              wq, 16
+    jge %%end_hv
+    mov            srcq, r11mp
+    mov            dstq, r12mp
+    lea           lumaq, [r14+wq*2]
+    add            srcq, wq
+    add            dstq, wq
+
+    ; since fg_dataq.overlap is guaranteed to be set, we never jump
+    ; back to .loop_x_v_overlap, and instead always fall-through to
+    ; h+v overlap
+
+%%loop_x_hv_overlap:
+    ; we assume from the block above that bits 8-15 of r7d are zero'ed
+    mov             r6d, seed
+    or             seed, 0xeff4eff4
+    test           seeb, seeh
+    setp            r7b                     ; parity of top_seed
+    shr            seed, 16
+    shl             r7d, 16
+    test           seeb, seeh
+    setp            r7b                     ; parity of cur_seed
+    or              r6d, 0x00010001
+    xor             r7d, r6d
+    rorx           seed, r7d, 1             ; updated (cur_seed << 16) | top_seed
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                offx, offy, see, left_offxy, top_offxy, topleft_offxy, lstride
+
+    lea  topleft_offxyq, [top_offxyq+16]
+    lea     left_offxyq, [offyq+16]
+    rorx          offyd, seed, 8
+    rorx          offxd, seed, 12
+    and           offyd, 0xf000f
+    and           offxd, 0xf000f
+    imul          offyd, 82
+    ; offxy=offy*stride+offx, (cur_offxy << 16) | top_offxy
+    lea           offyq, [offyq+offxq+0x10001*498+16*82]
+
+    DEFINE_ARGS dst, src, stride, luma, w, scaling, grain_lut, \
+                h, offxy, see, left_offxy, top_offxy, topleft_offxy, lstride
+
+    movzx    top_offxyd, offxyw
+    shr          offxyd, 16
+
+    mov              hd, hm
+    mov      grain_lutq, grain_lutmp
+%%loop_y_hv_overlap:
+    ; src
+    mova            xm4, [lumaq+lstrideq*0+ 0]
+    mova            xm6, [lumaq+lstrideq*0+16]
+    mova            xm0, [srcq]
+    vpbroadcastd     m7, [pb_1]
+    vinserti128      m4, [lumaq+lstrideq*2 +0], 1
+    vinserti128      m6, [lumaq+lstrideq*2+16], 1
+    vinserti128      m0, [srcq+strideq], 1
+    pxor             m2, m2
+    pmaddubsw        m4, m7
+    pmaddubsw        m6, m7
+    pavgw            m4, m2
+    pavgw            m6, m2
+
+%if %1
+    packuswb         m4, m6                 ; luma
+    punpckhbw        m6, m4, m0
+    punpcklbw        m4, m0                 ; { luma, chroma }
+    pmaddubsw        m6, m14
+    pmaddubsw        m4, m14
+    psraw            m6, 6
+    psraw            m4, 6
+    paddw            m6, m15
+    paddw            m4, m15
+    packuswb         m4, m6                 ; pack+unpack = clip
+    punpckhbw        m6, m4, m2
+    punpcklbw        m4, m2
+%endif
+
+    punpckhwd        m5, m4, m2
+    punpcklwd        m4, m2
+    punpckhwd        m7, m6, m2
+    punpcklwd        m6, m2                 ; m4-7: src as dword
+
+    ; scaling[src]
+    pcmpeqw          m9, m9
+    pcmpeqw          m3, m3
+    vpgatherdd       m8, [scalingq+m4], m9
+    vpgatherdd       m4, [scalingq+m5], m3
+    pcmpeqw          m9, m9
+    pcmpeqw          m3, m3
+    vpgatherdd       m5, [scalingq+m6], m9
+    vpgatherdd       m6, [scalingq+m7], m3
+    pand             m8, m10
+    pand             m4, m10
+    pand             m5, m10
+    pand             m6, m10
+    packusdw         m8, m4
+    packusdw         m5, m6
+
+    ; unpack chroma source
+    punpckhbw        m1, m0, m2
+    punpcklbw        m0, m2                 ; m0-1: src as word
+
+    ; grain = grain_lut[offy+y][offx+x]
+%if %1
+    vpbroadcastd     m9, [pb_23_22]
+%endif
+    movu            xm3, [grain_lutq+offxyq]
+    movq            xm6, [grain_lutq+top_offxyq]
+    vinserti128      m3, [grain_lutq+offxyq+82], 1
+    vinserti128      m6, [grain_lutq+top_offxyq+8], 1
+    movd            xm4, [grain_lutq+left_offxyq]
+    movd            xm7, [grain_lutq+topleft_offxyq]
+    vinserti128      m4, [grain_lutq+left_offxyq+82], 1
+    ; do h interpolation first (so top | top/left -> top, left | cur -> cur)
+    punpcklbw        m4, m3
+    punpcklbw       xm7, xm6
+%if %1
+    pmaddubsw        m4, m9, m4
+    pmaddubsw       xm7, xm9, xm7
+    pmulhrsw         m4, [pw_1024]
+    pmulhrsw        xm7, [pw_1024]
+%else
+    pmaddubsw        m4, m15, m4
+    pmaddubsw       xm7, xm15, xm7
+    pmulhrsw         m4, m14
+    pmulhrsw        xm7, xm14
+%endif
+    packsswb         m4, m4
+    packsswb        xm7, xm7
+    pcmpeqw          m9, m9                 ; this is kind of ugly
+    psrldq           m9, 15
+    vpblendvb        m3, m3, m4, m9
+    shufpd           m9, m9, m9, 1110b
+    vpblendvb        m6, m6, m7, m9
+    vpermq           m9, m3, q3120
+    ; followed by v interpolation (top | cur -> cur)
+    punpcklbw        m6, m9
+%if %1
+    vpbroadcastd     m9, [pb_23_22]
+    pmaddubsw        m6, m9, m6
+    pmulhrsw         m6, [pw_1024]
+%else
+    pmaddubsw        m6, m15, m6
+    pmulhrsw         m6, m14
+%endif
+    packsswb         m6, m6
+    vpermq           m6, m6, q3120
+    vpblendd         m3, m3, m6, 00001111b
+    pcmpgtb          m7, m2, m3
+    punpcklbw        m2, m3, m7
+    punpckhbw        m3, m7
+
+    ; noise = round2(scaling[src] * grain, scaling_shift)
+    pmullw           m2, m8
+    pmullw           m3, m5
+    pmulhrsw         m2, m11
+    pmulhrsw         m3, m11
+
+    ; dst = clip_pixel(src, noise)
+    paddw            m0, m2
+    paddw            m1, m3
+    pmaxsw           m0, m13
+    pmaxsw           m1, m13
+    pminsw           m0, m12
+    pminsw           m1, m12
+    packuswb         m0, m1
+    mova         [dstq], xm0
+    vextracti128 [dstq+strideq], m0, 1
+
+    lea            srcq, [srcq+strideq*2]
+    lea            dstq, [dstq+strideq*2]
+    lea           lumaq, [lumaq+lstrideq*4]
+    add      grain_lutq, 82*2
+    sub              hb, 2
+    jg %%loop_y_h_overlap
+
+%%end_y_hv_overlap:
+    add              wq, 16
+    jge %%end_hv
+    mov            srcq, r11mp
+    mov            dstq, r12mp
+    lea           lumaq, [r14+wq*2]
+    add            srcq, wq
+    add            dstq, wq
+    jmp %%loop_x_hv_overlap
+
+%%end_hv:
+    RET
+%endmacro
+
+    FGUV_32x32xN_LOOP 1
+.csfl:
+    FGUV_32x32xN_LOOP 0
 
 %endif ; ARCH_X86_64
--- a/src/x86/film_grain_init_tmpl.c
+++ b/src/x86/film_grain_init_tmpl.c
@@ -30,6 +30,7 @@
 
 decl_generate_grain_y_fn(dav1d_generate_grain_y_avx2);
 decl_fgy_32x32xn_fn(dav1d_fgy_32x32xn_avx2);
+decl_fguv_32x32xn_fn(dav1d_fguv_32x32xn_i420_avx2);
 
 COLD void bitfn(dav1d_film_grain_dsp_init_x86)(Dav1dFilmGrainDSPContext *const c) {
     const unsigned flags = dav1d_get_cpu_flags();
@@ -39,5 +40,6 @@
 #if BITDEPTH == 8 && ARCH_X86_64
     c->generate_grain_y = dav1d_generate_grain_y_avx2;
     c->fgy_32x32xn = dav1d_fgy_32x32xn_avx2;
+    c->fguv_32x32xn[DAV1D_PIXEL_LAYOUT_I420 - 1] = dav1d_fguv_32x32xn_i420_avx2;
 #endif
 }
--- a/tests/checkasm/filmgrain.c
+++ b/tests/checkasm/filmgrain.c
@@ -120,9 +120,7 @@
         for (int y = 0; y < h; y++)
             for (int x = 0; x < w; x++)
                 src[y * PXSTRIDE(stride) + x] = rnd() & bitdepth_max;
-        memcpy(a_dst, src, stride * h);
-        memcpy(c_dst, src, stride * h);
-        const int row_num = rnd() & 0x7ff;
+        const int row_num = rnd() & 1 ? rnd() & 0x7ff : 0;
 
         fg_data.clip_to_restricted_range = rnd() & 1;
         fg_data.scaling_shift = (rnd() & 3) + 8;
@@ -144,6 +142,122 @@
     report("fgy_32x32xn");
 }
 
+static void check_fguv_sbrow(const Dav1dFilmGrainDSPContext *const dsp) {
+    ALIGN_STK_32(pixel, c_dst, 128 * 32,);
+    ALIGN_STK_32(pixel, a_dst, 128 * 32,);
+    ALIGN_STK_32(pixel, src, 128 * 32,);
+    ALIGN_STK_32(pixel, luma_src, 128 * 32,);
+    const ptrdiff_t lstride = 128 * sizeof(pixel);
+
+    declare_func(void, pixel *dst_row, const pixel *src_row, ptrdiff_t stride,
+                 const Dav1dFilmGrainData *data, size_t pw,
+                 const uint8_t scaling[SCALING_SIZE],
+                 const entry grain_lut[][GRAIN_WIDTH], int bh, int row_num,
+                 const pixel *luma_row, ptrdiff_t luma_stride, int uv_pl,
+                 int is_identity HIGHBD_DECL_SUFFIX);
+
+    for (int layout_idx = 0; layout_idx < 3; layout_idx++) {
+        const char ss_name[][4] = {
+            [DAV1D_PIXEL_LAYOUT_I420 - 1] = "420",
+            [DAV1D_PIXEL_LAYOUT_I422 - 1] = "422",
+            [DAV1D_PIXEL_LAYOUT_I444 - 1] = "444",
+        };
+        const enum Dav1dPixelLayout layout = layout_idx + 1;
+        const int ss_x = layout != DAV1D_PIXEL_LAYOUT_I444;
+        const int ss_y = layout == DAV1D_PIXEL_LAYOUT_I420;
+        const ptrdiff_t stride = (ss_x ? 96 : 128) * sizeof(pixel);
+
+        for (int csfl = 0; csfl <= 1; csfl++) {
+            if (check_func(dsp->fguv_32x32xn[layout_idx],
+                           "fguv_32x32xn_%dbpc_%s_csfl%d",
+                           BITDEPTH, ss_name[layout_idx], csfl))
+            {
+                Dav1dFilmGrainData fg_data;
+
+                fg_data.seed = rnd() & 0xFFFF;
+
+#if BITDEPTH == 16
+                const int bitdepth_max = rnd() & 1 ? 0x3ff : 0xfff;
+#else
+                const int bitdepth_max = 0xff;
+#endif
+                const int uv_pl = rnd() & 1;
+                const int is_identity = rnd() & 1;
+
+                uint8_t scaling[SCALING_SIZE];
+                entry grain_lut[2][GRAIN_HEIGHT + 1][GRAIN_WIDTH];
+                fg_data.grain_scale_shift = rnd() & 3;
+                fg_data.ar_coeff_shift = (rnd() & 3) + 6;
+                fg_data.ar_coeff_lag = rnd() & 3;
+                const int num_y_pos = 2 * fg_data.ar_coeff_lag * (fg_data.ar_coeff_lag + 1);
+                for (int n = 0; n < num_y_pos; n++)
+                    fg_data.ar_coeffs_y[n] = (rnd() & 0xff) - 128;
+                dsp->generate_grain_y(grain_lut[0], &fg_data HIGHBD_TAIL_SUFFIX);
+                dsp->generate_grain_uv[layout_idx](grain_lut[1], grain_lut[0],
+                                                   &fg_data, uv_pl HIGHBD_TAIL_SUFFIX);
+
+                const int w = 1 + (rnd() & (127 >> ss_x));
+                const int h = 1 + (rnd() & (31 >> ss_y));
+                const int lw = w << ss_x, lh = h << ss_y;
+
+                for (int y = 0; y < h; y++)
+                    for (int x = 0; x < w; x++)
+                        src[y * PXSTRIDE(stride) + x] = rnd() & bitdepth_max;
+                for (int y = 0; y < lh; y++)
+                    for (int x = 0; x < lw; x++)
+                        luma_src[y * PXSTRIDE(lstride) + x] = rnd() & bitdepth_max;
+                const int row_num = rnd() & 1 ? rnd() & 0x7ff : 0;
+
+                if (csfl) {
+                    fg_data.num_y_points = 2 + (rnd() % 13);
+                    const int pad = 0xff / fg_data.num_y_points;
+                    for (int n = 0; n < fg_data.num_y_points; n++) {
+                        fg_data.y_points[n][0] = 0xff * n / fg_data.num_y_points;
+                        fg_data.y_points[n][0] += rnd() % pad;
+                        fg_data.y_points[n][1] = rnd() & 0xff;
+                    }
+                    generate_scaling(bitdepth_from_max(bitdepth_max), fg_data.y_points,
+                                     fg_data.num_y_points, scaling);
+                } else {
+                    fg_data.num_uv_points[uv_pl] = 2 + (rnd() % 9);
+                    const int pad = 0xff / fg_data.num_uv_points[uv_pl];
+                    for (int n = 0; n < fg_data.num_uv_points[uv_pl]; n++) {
+                        fg_data.uv_points[uv_pl][n][0] = 0xff * n / fg_data.num_uv_points[uv_pl];
+                        fg_data.uv_points[uv_pl][n][0] += rnd() % pad;
+                        fg_data.uv_points[uv_pl][n][1] = rnd() & 0xff;
+                    }
+                    generate_scaling(bitdepth_from_max(bitdepth_max), fg_data.uv_points[uv_pl],
+                                     fg_data.num_uv_points[uv_pl], scaling);
+
+                    fg_data.uv_mult[uv_pl] = (rnd() & 0xff) - 128;
+                    fg_data.uv_luma_mult[uv_pl] = (rnd() & 0xff) - 128;
+                    fg_data.uv_offset[uv_pl] = (rnd() & 0x1ff) - 256;
+                }
+
+                fg_data.clip_to_restricted_range = rnd() & 1;
+                fg_data.scaling_shift = (rnd() & 3) + 8;
+                fg_data.chroma_scaling_from_luma = csfl;
+                for (fg_data.overlap_flag = 0; fg_data.overlap_flag <= 1;
+                     fg_data.overlap_flag++)
+                {
+                    call_ref(c_dst, src, stride, &fg_data, w, scaling, grain_lut[1], h,
+                             row_num, luma_src, lstride, uv_pl, is_identity HIGHBD_TAIL_SUFFIX);
+                    call_new(a_dst, src, stride, &fg_data, w, scaling, grain_lut[1], h,
+                             row_num, luma_src, lstride, uv_pl, is_identity HIGHBD_TAIL_SUFFIX);
+
+                    checkasm_check_pixel(c_dst, stride, a_dst, stride, w, h, "dst");
+                }
+
+                fg_data.overlap_flag = 1;
+                bench_new(a_dst, src, stride, &fg_data, 32, scaling, grain_lut[1], 16,
+                          row_num, luma_src, lstride, uv_pl, is_identity HIGHBD_TAIL_SUFFIX);
+            }
+        }
+    }
+
+    report("fguv_32x32xn");
+}
+
 void bitfn(checkasm_check_filmgrain)(void) {
     Dav1dFilmGrainDSPContext c;
 
@@ -151,4 +265,5 @@
 
     check_gen_grny(&c);
     check_fgy_sbrow(&c);
+    check_fguv_sbrow(&c);
 }