diff --git a/src/internal.rs b/src/internal.rs
index 21dc5d9a7..24fadeae6 100644
--- a/src/internal.rs
+++ b/src/internal.rs
@@ -939,6 +939,7 @@ pub struct ScratchCompinter {
     pub seg_mask: [u8; 16384],
 }
 
+// Larger of the two between `ScratchCompinter` and `[BD::Pixel; 128 * 32]`.
 const SCRATCH_COMPINTER_SIZE: usize = mem::size_of::<ScratchCompinter>();
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
@@ -955,15 +956,14 @@ impl ScratchLapInter {
     }
 }
 
-const EMU_EDGE_SIZE: usize = 320 * (256 + 7);
+const EMU_EDGE_LEN: usize = 320 * (256 + 7);
 // stride=192 for non-SVC, or 320 for SVC
-// Contains `320 * (256 + 7)` elements of either `u8` or `u16` depending on bitdepth.
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C, align(32))]
-pub struct EmuEdge([u8; EMU_EDGE_SIZE * 2]);
+pub struct ScratchEmuEdge([u8; EMU_EDGE_LEN * 2]);
 
-impl EmuEdge {
-    pub fn buf_mut<BD: BitDepth>(&mut self) -> &mut [BD::Pixel; EMU_EDGE_SIZE] {
+impl ScratchEmuEdge {
+    pub fn buf_mut<BD: BitDepth>(&mut self) -> &mut [BD::Pixel; EMU_EDGE_LEN] {
         FromBytes::mut_from_prefix(&mut self.0).unwrap()
     }
 }
@@ -972,7 +972,7 @@ impl EmuEdge {
 #[repr(C)]
 pub struct ScratchInter {
     pub lap_inter: ScratchLapInter,
-    pub emu_edge: EmuEdge,
+    pub emu_edge: ScratchEmuEdge,
 }
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
@@ -982,25 +982,10 @@ pub struct ScratchPal {
     pub pal_ctx: [u8; 64],
 }
 
-impl Default for ScratchPal {
-    fn default() -> Self {
-        Self {
-            pal_order: [[0; 8]; 64],
-            pal_ctx: [0; 64],
-        }
-    }
-}
-
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C, align(64))]
 pub struct ScratchLevelsPal([u8; 1088]);
 
-impl Default for ScratchLevelsPal {
-    fn default() -> Self {
-        Self([0; 1088])
-    }
-}
-
 impl ScratchLevelsPal {
     pub fn levels_mut(&mut self) -> &mut [u8; 1088] {
         &mut self.0
@@ -1013,9 +998,9 @@ impl ScratchLevelsPal {
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C, align(64))]
-pub struct InterIntraEdgePalInterintra([u8; 64 * 64 * 2]);
+pub struct ScratchInterintraBuf([u8; 64 * 64 * 2]);
 
-impl InterIntraEdgePalInterintra {
+impl ScratchInterintraBuf {
     pub fn buf_mut<BD: BitDepth>(&mut self) -> &mut [BD::Pixel; 64 * 64] {
         FromBytes::mut_from_prefix(&mut self.0).unwrap()
     }
@@ -1023,9 +1008,9 @@ impl InterIntraEdgePalInterintra {
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C, align(32))]
-pub struct InterIntraEdgePalEdge([u8; 257 * 2 + 30]); // 257 Pixel elements + 30 padding bytes
+pub struct ScratchEdgeBuf([u8; 257 * 2 + 30]); // 257 Pixel elements + 30 padding bytes
 
-impl InterIntraEdgePalEdge {
+impl ScratchEdgeBuf {
     pub fn buf_mut<BD: BitDepth>(&mut self) -> &mut [BD::Pixel; 257] {
         FromBytes::mut_from_prefix(&mut self.0).unwrap()
     }
@@ -1033,10 +1018,9 @@ impl InterIntraEdgePalEdge {
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C, align(16))]
-pub struct InterIntraEdgePalPal([u8; 8 * 3 * 2]); /* [3 plane][8 palette_idx] */
-
+pub struct ScratchPalBuf([u8; 8 * 3 * 2]); /* [3 plane][8 palette_idx] */
 
-impl InterIntraEdgePalPal {
+impl ScratchPalBuf {
     pub fn buf<BD: BitDepth>(&self) -> &[[BD::Pixel; 8]; 3] {
         FromBytes::ref_from_prefix(&self.0).unwrap()
     }
@@ -1048,10 +1032,10 @@ impl InterIntraEdgePalPal {
 
 #[derive(Clone, Copy, FromZeroes, FromBytes, AsBytes)]
 #[repr(C)]
-pub struct InterIntraEdgePal {
-    pub interintra: InterIntraEdgePalInterintra,
-    pub edge: InterIntraEdgePalEdge,
-    pub pal: InterIntraEdgePalPal,
+pub struct ScratchInterintraEdgePal {
+    pub interintra: ScratchInterintraBuf,
+    pub edge: ScratchEdgeBuf,
+    pub pal: ScratchPalBuf,
     _padding: [u8; 48],
 }
 
@@ -1070,7 +1054,6 @@ impl ScratchAcTxtpMap {
         FromBytes::mut_from_prefix(&mut self.0).unwrap()
     }
 
-    #[track_caller]
     pub fn txtp_map(&self) -> &[TxfmType; 1024] {
         FromBytes::ref_from_prefix(&self.0).unwrap()
     }
@@ -1086,7 +1069,7 @@ pub struct ScratchInterIntra {
     pub levels_pal: ScratchLevelsPal,
     pub ac_txtp_map: ScratchAcTxtpMap,
     pub pal_idx: [u8; 8192],
-    pub interintra_edge_pal: InterIntraEdgePal,
+    pub interintra_edge_pal: ScratchInterintraEdgePal,
 }
 
 // Larger of the two between `ScratchInter` and `ScratchInterIntra`.
@@ -1100,7 +1083,6 @@ impl TaskContextScratch {
         FromBytes::mut_from_prefix(&mut self.0).unwrap()
     }
 
-    #[track_caller]
     pub fn inter_intra(&self) -> &ScratchInterIntra {
         FromBytes::ref_from_prefix(&self.0).unwrap()
     }
diff --git a/src/recon.rs b/src/recon.rs
index 9eb6e2b06..1a9f6e837 100644
--- a/src/recon.rs
+++ b/src/recon.rs
@@ -19,11 +19,11 @@ use crate::src::ctx::CaseSet;
 use crate::src::env::get_uv_inter_txtp;
 use crate::src::internal::Bxy;
 use crate::src::internal::CodedBlockInfo;
-use crate::src::internal::EmuEdge;
 use crate::src::internal::Rav1dContext;
 use crate::src::internal::Rav1dDSPContext;
 use crate::src::internal::Rav1dFrameData;
 use crate::src::internal::Rav1dTaskContext;
+use crate::src::internal::ScratchEmuEdge;
 use crate::src::internal::TileStateRef;
 use crate::src::intra_edge::EdgeFlags;
 use crate::src::ipred_prepare::rav1d_prepare_intra_edges;
@@ -2024,7 +2024,7 @@ pub(crate) unsafe fn rav1d_read_coef_blocks<BD: BitDepth>(
 
 unsafe fn mc<BD: BitDepth>(
     f: &Rav1dFrameData,
-    emu_edge: &mut EmuEdge,
+    emu_edge: &mut ScratchEmuEdge,
     b: Bxy,
     dst8: *mut BD::Pixel,
     dst16: *mut i16,
@@ -2311,7 +2311,7 @@ unsafe fn obmc<BD: BitDepth>(
 
 unsafe fn warp_affine<BD: BitDepth>(
     f: &Rav1dFrameData,
-    emu_edge: &mut EmuEdge,
+    emu_edge: &mut ScratchEmuEdge,
     b: Bxy,
     mut dst8: *mut BD::Pixel,
     mut dst16: *mut i16,