diff --git a/Cargo.lock b/Cargo.lock
index 641c48e6..46aba376 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -60,7 +60,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "cc"
-version = "1.0.60"
+version = "1.0.61"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -107,7 +107,7 @@ name = "cloudflare-zlib-sys"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -247,7 +247,7 @@ name = "libdeflate-sys"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -289,7 +289,7 @@ dependencies = [
 
 [[package]]
 name = "miniz_oxide"
-version = "0.4.2"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "adler 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -356,7 +356,7 @@ dependencies = [
  "itertools 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libdeflater 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "miniz_oxide 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "miniz_oxide 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rgb 0.8.25 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -561,7 +561,7 @@ dependencies = [
 "checksum build_const 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "39092a32794787acd8525ee150305ff051b0aa6cc2abaf193924f5ab05425f39"
 "checksum bytemuck 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "41aa2ec95ca3b5c54cf73c91acf06d24f4495d5f1b1c12506ae3483d646177ac"
 "checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
-"checksum cc 1.0.60 (registry+https://github.com/rust-lang/crates.io-index)" = "ef611cc68ff783f18535d77ddd080185275713d852c4f5cbb6122c462a7a825c"
+"checksum cc 1.0.61 (registry+https://github.com/rust-lang/crates.io-index)" = "ed67cbde08356238e75fc4656be4749481eeffb09e19f320a25237d5221c985d"
 "checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 "checksum chrono 0.4.19 (registry+https://github.com/rust-lang/crates.io-index)" = "670ad68c9088c2a963aaa298cb369688cf3f9465ce5e2d4ca10e6e0098a1ce73"
 "checksum clap 2.33.3 (registry+https://github.com/rust-lang/crates.io-index)" = "37e58ac78573c40708d45522f0d80fa2f01cc4f9b4e2bf749807255454312002"
@@ -589,7 +589,7 @@ dependencies = [
 "checksum maybe-uninit 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "60302e4db3a61da70c0cb7991976248362f30319e88850c487b9b95bbf059e00"
 "checksum memoffset 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)" = "043175f069eda7b85febe4a74abbaeff828d9f8b448515d3151a14a3542811aa"
 "checksum miniz_oxide 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "791daaae1ed6889560f8c4359194f56648355540573244a5448a83ba1ecc7435"
-"checksum miniz_oxide 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c60c0dfe32c10b43a144bad8fc83538c52f58302c92300ea7ec7bf7b38d5a7b9"
+"checksum miniz_oxide 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "0f2d26ec3309788e423cfbf68ad1800f061638098d76a83681af979dc4eda19d"
 "checksum num-integer 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)" = "8d59457e662d541ba17869cf51cf177c0b5f0cbf476c66bdc90bf1edac4f875b"
 "checksum num-iter 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e6b7c748f995c4c29c5f5ae0248536e04a5739927c74ec0fa564805094b9f"
 "checksum num-rational 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a5b4d7360f362cfb50dde8143501e6940b22f644be75a4cc90b2d81968908138"
diff --git a/src/reduction/alpha.rs b/src/reduction/alpha.rs
index 8412aba1..cd25a81a 100644
--- a/src/reduction/alpha.rs
+++ b/src/reduction/alpha.rs
@@ -64,9 +64,7 @@ fn reduced_alpha_to_black(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         reduced.push(line.filter);
         for pixel in line.data.chunks(bpp) {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
-                for _ in 0..bpp {
-                    reduced.push(0);
-                }
+                reduced.resize(reduced.len() + bpp, 0);
             } else {
                 reduced.extend_from_slice(pixel);
             }
@@ -81,12 +79,8 @@ fn reduced_alpha_to_white(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         reduced.push(line.filter);
         for pixel in line.data.chunks(bpp) {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
-                for _ in 0..(bpp - bpc) {
-                    reduced.push(255);
-                }
-                for _ in 0..bpc {
-                    reduced.push(0);
-                }
+                reduced.resize(reduced.len() + bpp - bpc, 255);
+                reduced.resize(reduced.len() + bpc, 0);
             } else {
                 reduced.extend_from_slice(pixel);
             }
@@ -109,9 +103,7 @@ fn reduced_alpha_to_up(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         for (pixel, last_pixel) in line.data.chunks(bpp).zip(last_line.chunks(bpp)) {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
                 current_line.extend_from_slice(&last_pixel[0..(bpp - bpc)]);
-                for _ in 0..bpc {
-                    current_line.push(0);
-                }
+                current_line.resize(current_line.len() + bpc, 0);
             } else {
                 current_line.extend_from_slice(pixel);
             }
@@ -134,9 +126,7 @@ fn reduced_alpha_to_down(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         for (pixel, last_pixel) in line.data.chunks(bpp).zip(last_line.chunks(bpp)) {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
                 reduced.extend_from_slice(&last_pixel[0..(bpp - bpc)]);
-                for _ in 0..bpc {
-                    reduced.push(0);
-                }
+                reduced.resize(reduced.len() + bpc, 0);
             } else {
                 reduced.extend_from_slice(pixel);
             }
@@ -154,9 +144,7 @@ fn reduced_alpha_to_left(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         for pixel in line.data.chunks(bpp).rev() {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
                 line_bytes.extend_from_slice(&last_pixel[0..(bpp - bpc)]);
-                for _ in 0..bpc {
-                    line_bytes.push(0);
-                }
+                line_bytes.resize(line_bytes.len() + bpc, 0);
             } else {
                 line_bytes.extend_from_slice(pixel);
             }
@@ -176,9 +164,7 @@ fn reduced_alpha_to_right(png: &PngImage, bpc: usize, bpp: usize) -> Vec<u8> {
         for pixel in line.data.chunks(bpp) {
             if pixel.iter().skip(bpp - bpc).fold(0, |sum, i| sum | i) == 0 {
                 reduced.extend_from_slice(&last_pixel[0..(bpp - bpc)]);
-                for _ in 0..bpc {
-                    reduced.push(0);
-                }
+                reduced.resize(reduced.len() + bpc, 0);
             } else {
                 reduced.extend_from_slice(pixel);
             }