diff --git a/src/libImaging/Convert.c b/src/libImaging/Convert.c
index 4a35a9a1fb1..b2b7ff26a22 100644
--- a/src/libImaging/Convert.c
+++ b/src/libImaging/Convert.c
@@ -587,17 +587,11 @@ l2i(UINT8 *out_, const UINT8 *in, int xsize) {
 
 static void
 i2l(UINT8 *out, const UINT8 *in_, int xsize) {
-    int x;
-    for (x = 0; x < xsize; x++, out++, in_ += 4) {
+    for (int x = 0; x < xsize; x++, out++, in_ += 4) {
         INT32 v;
         memcpy(&v, in_, sizeof(v));
-        if (v <= 0) {
-            *out = 0;
-        } else if (v >= 255) {
-            *out = 255;
-        } else {
-            *out = (UINT8)v;
-        }
+        // Branchless saturation
+        *out = (UINT8)(v <= 0 ? 0 : (v >= 255 ? 255 : v));
     }
 }
 
@@ -980,27 +974,30 @@ pa2f(UINT8 *out_, const UINT8 *in, int xsize, ImagingPalette palette) {
     }
 }
 
+// Set the alpha channel of the UINT32 `v` in-place to the given value.
+#ifdef WORDS_BIGENDIAN
+#define SET_ALPHA_32(v, alpha) v = ((v & 0xFFFFFF00u) | (alpha))
+#else
+#define SET_ALPHA_32(v, alpha) v = ((v & 0x00FFFFFFu) | ((UINT32)(alpha) << 24))
+#endif
+
 static void
 p2rgb(UINT8 *out, const UINT8 *in, int xsize, ImagingPalette palette) {
-    int x;
-    for (x = 0; x < xsize; x++) {
-        const UINT8 *rgb = &palette->palette[*in++ * 4];
-        *out++ = rgb[0];
-        *out++ = rgb[1];
-        *out++ = rgb[2];
-        *out++ = 255;
+    for (int x = 0; x < xsize; x++, in++, out += 4) {
+        UINT32 v;
+        memcpy(&v, &palette->palette[in[0] * 4], sizeof(v));
+        SET_ALPHA_32(v, 0xFF);
+        memcpy(out, &v, sizeof(v));
     }
 }
 
 static void
 pa2rgb(UINT8 *out, const UINT8 *in, int xsize, ImagingPalette palette) {
-    int x;
-    for (x = 0; x < xsize; x++, in += 4) {
-        const UINT8 *rgb = &palette->palette[in[0] * 4];
-        *out++ = rgb[0];
-        *out++ = rgb[1];
-        *out++ = rgb[2];
-        *out++ = 255;
+    for (int x = 0; x < xsize; x++, in += 4, out += 4) {
+        UINT32 v;
+        memcpy(&v, &palette->palette[in[0] * 4], sizeof(v));
+        SET_ALPHA_32(v, 0xFF);
+        memcpy(out, &v, sizeof(v));
     }
 }
 
@@ -1026,25 +1023,18 @@ pa2hsv(UINT8 *out, const UINT8 *in, int xsize, ImagingPalette palette) {
 
 static void
 p2rgba(UINT8 *out, const UINT8 *in, int xsize, ImagingPalette palette) {
-    int x;
-    for (x = 0; x < xsize; x++) {
-        const UINT8 *rgba = &palette->palette[*in++ * 4];
-        *out++ = rgba[0];
-        *out++ = rgba[1];
-        *out++ = rgba[2];
-        *out++ = rgba[3];
+    for (int x = 0; x < xsize; x++, in++, out += 4) {
+        memcpy(out, &palette->palette[in[0] * 4], 4);
     }
 }
 
 static void
 pa2rgba(UINT8 *out, const UINT8 *in, int xsize, ImagingPalette palette) {
-    int x;
-    for (x = 0; x < xsize; x++, in += 4) {
-        const UINT8 *rgb = &palette->palette[in[0] * 4];
-        *out++ = rgb[0];
-        *out++ = rgb[1];
-        *out++ = rgb[2];
-        *out++ = in[3];
+    for (int x = 0; x < xsize; x++, in += 4, out += 4) {
+        UINT32 v;
+        memcpy(&v, &palette->palette[in[0] * 4], sizeof(v));
+        SET_ALPHA_32(v, in[3]);
+        memcpy(out, &v, sizeof(v));
     }
 }