diff --git a/build.rs b/build.rs
index 705b48546..73f13e00c 100644
--- a/build.rs
+++ b/build.rs
@@ -145,7 +145,7 @@ mod asm {
         fs::write(&config_path, &config_contents).unwrap();
 
         // Note that avx* is never (at runtime) supported on x86.
-        let x86_generic = &["cdef_sse", "itx_sse", "msac", "refmvs"][..];
+        let x86_generic = &["cdef_sse", "itx_sse", "msac", "pal", "refmvs"][..];
         let x86_64_generic = &[
             "cdef_avx2",
             "itx_avx2",
diff --git a/lib.rs b/lib.rs
index b449c0320..538af4992 100644
--- a/lib.rs
+++ b/lib.rs
@@ -68,6 +68,7 @@ pub mod src {
     mod mem;
     mod msac;
     mod obu;
+    mod pal;
     mod picture;
     mod qm;
     mod recon;
diff --git a/src/decode.rs b/src/decode.rs
index ee78ffbba..68b489dd3 100644
--- a/src/decode.rs
+++ b/src/decode.rs
@@ -124,6 +124,7 @@ use crate::src::msac::rav1d_msac_decode_symbol_adapt4;
 use crate::src::msac::rav1d_msac_decode_symbol_adapt8;
 use crate::src::msac::rav1d_msac_decode_uniform;
 use crate::src::msac::rav1d_msac_init;
+use crate::src::pal::Rav1dPalDSPContext;
 use crate::src::picture::rav1d_picture_alloc_copy;
 use crate::src::picture::rav1d_picture_ref;
 use crate::src::picture::rav1d_picture_unref_internal;
@@ -699,6 +700,7 @@ fn order_palette(
 
 unsafe fn read_pal_indices(
     ts: &mut Rav1dTileState,
+    pal_dsp: &Rav1dPalDSPContext,
     scratch_pal: &mut Rav1dTaskContext_scratch_pal,
     pal_tmp: &mut [u8],
     pal_idx: Option<&mut [u8]>, // if None, use pal_tmp instead of pal_idx
@@ -743,35 +745,14 @@ unsafe fn read_pal_indices(
             pal_tmp[offset..][..len].fill(filler);
         }
     }
-    if let Some(pal_idx) = pal_idx {
-        for i in 0..bw4 * h4 * 8 {
-            pal_idx[i] = pal_tmp[2 * i + 0] | (pal_tmp[2 * i + 1] << 4);
-        }
-        if h4 < bh4 {
-            let y_start = h4 * 4;
-            let len = bw4 * 2;
-            let packed_stride = bw4 * 2;
-            let (src, dests) = pal_idx.split_at_mut(packed_stride * y_start);
-            let src = &src[bw4 * h4 * 8 - packed_stride..][..len];
-            for y in 0..(bh4 - h4) * 4 {
-                dests[y * packed_stride..][..len].copy_from_slice(src);
-            }
-        }
-    } else {
-        for i in 0..bw4 * h4 * 8 {
-            pal_tmp[i] = pal_tmp[2 * i + 0] | (pal_tmp[2 * i + 1] << 4);
-        }
-        if h4 < bh4 {
-            let y_start = h4 * 4;
-            let len = bw4 * 2;
-            let packed_stride = bw4 * 2;
-            let (src, dests) = pal_tmp.split_at_mut(packed_stride * y_start);
-            let src = &src[bw4 * h4 * 8 - packed_stride..][..len];
-            for y in 0..(bh4 - h4) * 4 {
-                dests[y * packed_stride..][..len].copy_from_slice(src);
-            }
-        }
-    }
+    (pal_dsp.pal_idx_finish)(
+        pal_idx.unwrap_or(pal_tmp).as_mut_ptr(),
+        pal_tmp.as_ptr(),
+        bw4 as c_int * 4,
+        bh4 as c_int * 4,
+        w4 as c_int * 4,
+        h4 as c_int * 4,
+    );
 }
 
 unsafe fn read_vartx_tree(
@@ -1805,6 +1786,7 @@ unsafe fn decode_b(
             };
             read_pal_indices(
                 ts,
+                &c.pal_dsp,
                 &mut t.scratch.c2rust_unnamed_0.c2rust_unnamed.c2rust_unnamed,
                 &mut t.scratch.c2rust_unnamed_0.pal_idx_uv,
                 Some(pal_idx),
@@ -1837,6 +1819,7 @@ unsafe fn decode_b(
             };
             read_pal_indices(
                 ts,
+                &c.pal_dsp,
                 &mut t.scratch.c2rust_unnamed_0.c2rust_unnamed.c2rust_unnamed,
                 &mut t.scratch.c2rust_unnamed_0.pal_idx_uv,
                 pal_idx,
diff --git a/src/internal.rs b/src/internal.rs
index a9dd47990..7a011bc56 100644
--- a/src/internal.rs
+++ b/src/internal.rs
@@ -55,6 +55,7 @@ use crate::src::looprestoration::Rav1dLoopRestorationDSPContext;
 use crate::src::mc::Rav1dMCDSPContext;
 use crate::src::mem::Rav1dMemPool;
 use crate::src::msac::MsacContext;
+use crate::src::pal::Rav1dPalDSPContext;
 use crate::src::picture::PictureFlags;
 use crate::src::picture::Rav1dThreadPicture;
 use crate::src::recon::backup_ipred_edge_fn;
@@ -339,6 +340,7 @@ pub struct Rav1dContext {
     pub(crate) refs: [Rav1dContext_refs; 8],
     pub(crate) cdf: [CdfThreadContext; 8], // Previously pooled
 
+    pub(crate) pal_dsp: Rav1dPalDSPContext,
     pub(crate) refmvs_dsp: Rav1dRefmvsDSPContext,
 
     pub(crate) allocator: Rav1dPicAllocator,
diff --git a/src/lib.rs b/src/lib.rs
index 4253da7fa..295a601e7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -41,6 +41,7 @@ use crate::src::mem::rav1d_mem_pool_end;
 use crate::src::mem::rav1d_mem_pool_init;
 use crate::src::obu::rav1d_parse_obus;
 use crate::src::obu::rav1d_parse_sequence_header;
+use crate::src::pal::ravid_pal_dsp_init;
 use crate::src::picture::dav1d_default_picture_alloc;
 use crate::src::picture::dav1d_default_picture_release;
 use crate::src::picture::rav1d_picture_alloc_copy;
@@ -334,6 +335,7 @@ pub(crate) unsafe fn rav1d_open(c_out: &mut *mut Rav1dContext, s: &Rav1dSettings
             }
         })
         .collect();
+    ravid_pal_dsp_init(&mut (*c).pal_dsp);
     rav1d_refmvs_dsp_init(&mut (*c).refmvs_dsp);
     Ok(())
 }
diff --git a/src/pal.rs b/src/pal.rs
new file mode 100644
index 000000000..b9a3dadf4
--- /dev/null
+++ b/src/pal.rs
@@ -0,0 +1,139 @@
+use crate::src::cpu::rav1d_get_cpu_flags;
+use crate::src::cpu::CpuFlags;
+use cfg_if::cfg_if;
+use libc::c_int;
+use std::slice;
+
+pub type pal_idx_finish_fn = unsafe extern "C" fn(
+    dst: *mut u8,
+    src: *const u8,
+    bw: c_int,
+    bh: c_int,
+    w: c_int,
+    h: c_int,
+) -> ();
+
+#[repr(C)]
+pub(crate) struct Rav1dPalDSPContext {
+    pub pal_idx_finish: pal_idx_finish_fn,
+}
+
+// fill invisible edges and pack to 4-bit (2 pixels per byte)
+unsafe extern "C" fn pal_idx_finish_rust(
+    dst: *mut u8,
+    src: *const u8,
+    bw: c_int,
+    bh: c_int,
+    w: c_int,
+    h: c_int,
+) -> () {
+    assert!(bw >= 4 && bw <= 64 && (bw & (bw - 1)) == 0);
+    assert!(bh >= 4 && bh <= 64 && (bh & (bh - 1)) == 0);
+    assert!(w >= 4 && w <= bw && (w & 3) == 0);
+    assert!(h >= 4 && h <= bh && (h & 3) == 0);
+
+    let w = w as usize;
+    let h = h as usize;
+    let bw = bw as usize;
+    let bh = bh as usize;
+    let dst_w = w / 2;
+    let dst_bw = bw / 2;
+
+    let mut dst = slice::from_raw_parts_mut(dst, dst_bw * bh);
+    let mut src = slice::from_raw_parts(src, bw * bh);
+
+    for y in 0..h {
+        for x in 0..dst_w {
+            dst[x] = src[2 * x] | (src[2 * x + 1] << 4)
+        }
+        if dst_w < dst_bw {
+            for x in dst_w..dst_bw {
+                dst[x] = 0x11 * src[w];
+            }
+        }
+        src = &src[bw..];
+        if y < h - 1 {
+            dst = &mut dst[dst_bw..];
+        }
+    }
+
+    if h < bh {
+        let (last_row, dst) = dst.split_at_mut(dst_bw);
+
+        for row in dst.chunks_exact_mut(dst_bw) {
+            row.copy_from_slice(last_row);
+        }
+    }
+}
+
+#[cfg(all(feature = "asm", any(target_arch = "x86", target_arch = "x86_64"),))]
+extern "C" {
+    fn dav1d_pal_idx_finish_ssse3(
+        dst: *mut u8,
+        src: *const u8,
+        bw: c_int,
+        bh: c_int,
+        w: c_int,
+        h: c_int,
+    );
+}
+
+#[cfg(all(feature = "asm", any(target_arch = "x86_64"),))]
+extern "C" {
+    fn dav1d_pal_idx_finish_avx2(
+        dst: *mut u8,
+        src: *const u8,
+        bw: c_int,
+        bh: c_int,
+        w: c_int,
+        h: c_int,
+    );
+
+    fn dav1d_pal_idx_finish_avx512icl(
+        dst: *mut u8,
+        src: *const u8,
+        bw: c_int,
+        bh: c_int,
+        w: c_int,
+        h: c_int,
+    );
+}
+
+#[inline(always)]
+#[cfg(all(feature = "asm", any(target_arch = "x86", target_arch = "x86_64"),))]
+unsafe fn pal_dsp_init_x86(c: *mut Rav1dPalDSPContext) {
+    let flags = rav1d_get_cpu_flags();
+
+    if !flags.contains(CpuFlags::SSSE3) {
+        return;
+    }
+
+    (*c).pal_idx_finish = dav1d_pal_idx_finish_ssse3;
+
+    cfg_if! {
+        if #[cfg(any(target_arch = "x86_64"))] {
+            if !flags.contains(CpuFlags::AVX2) {
+                return;
+            }
+
+            (*c).pal_idx_finish = dav1d_pal_idx_finish_avx2;
+
+            if !flags.contains(CpuFlags::AVX512ICL) {
+                return;
+            }
+
+            (*c).pal_idx_finish = dav1d_pal_idx_finish_avx512icl;
+        }
+    }
+}
+
+pub(crate) unsafe fn ravid_pal_dsp_init(c: *mut Rav1dPalDSPContext) -> () {
+    (*c).pal_idx_finish = pal_idx_finish_rust;
+
+    #[cfg(feature = "asm")]
+    cfg_if! {
+        if #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
+            pal_dsp_init_x86(c);
+        }
+    }
+}