diff --git a/Cargo.lock b/Cargo.lock
index 4b5b4ba..a811071 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -222,14 +222,6 @@ dependencies = [
  "quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "inflate"
-version = "0.4.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "adler32 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "lazy_static"
 version = "1.3.0"
@@ -253,6 +245,14 @@ name = "memchr"
 version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "miniz_oxide"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "adler32 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "multiplicative-persistence"
 version = "0.1.0"
@@ -264,7 +264,7 @@ dependencies = [
  "num-bigint 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "png 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "png 0.16.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "threadpool 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -316,13 +316,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "png"
-version = "0.16.3"
+version = "0.16.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "deflate 0.8.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "inflate 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "miniz_oxide 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -543,18 +543,18 @@ dependencies = [
 "checksum gobject-sys 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "31d1a804f62034eccf370006ccaef3708a71c31d561fee88564abe71177553d9"
 "checksum hermit-abi 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "307c3c9f937f38e3534b1d6447ecf090cafcc9744e4a6360e8b037b2cf5af120"
 "checksum humantime 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "df004cfca50ef23c36850aaaa59ad52cc70d0e90243c3c7737a4dd32dc7a3c4f"
-"checksum inflate 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "1cdb29978cc5797bd8dcc8e5bf7de604891df2a8dc576973d71a281e916db2ff"
 "checksum lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bc5729f27f159ddd61f4df6228e827e86643d4d3e7c32183cb30a1c08f604a14"
 "checksum libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)" = "1a31a0627fdf1f6a39ec0dd577e101440b7db22672c0901fe00a9a6fbb5c24e8"
 "checksum log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)" = "14b6052be84e6b71ab17edffc2eeabf5c2c3ae1fdb464aae35ac50c67a44e1f7"
 "checksum memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2efc7bc57c883d4a4d6e3246905283d8dae951bb3bd32f49d6ef297f546e1c39"
+"checksum miniz_oxide 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "791daaae1ed6889560f8c4359194f56648355540573244a5448a83ba1ecc7435"
 "checksum num-bigint 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "090c7f9998ee0ff65aa5b723e4009f7b217707f1fb5ea551329cc4d6231fb304"
 "checksum num-integer 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "3f6ea62e9d81a77cd3ee9a2a5b9b609447857f3d358704331e4ef39eb247fcba"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "05499f3756671c15885fee9034446956fff3f243d6077b91e5767df161f766b3"
 "checksum pin-utils 0.1.0-alpha.4 (registry+https://github.com/rust-lang/crates.io-index)" = "5894c618ce612a3fa23881b152b608bafb8c56cfc22f434a3ba3120b40f7b587"
 "checksum pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
-"checksum png 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2c68a431ed29933a4eb5709aca9800989758c97759345860fa5db3cfced0b65d"
+"checksum png 0.16.7 (registry+https://github.com/rust-lang/crates.io-index)" = "dfe7f9f1c730833200b134370e1d5098964231af8450bce9b78ee3ab5278b970"
 "checksum proc-macro-hack 0.5.11 (registry+https://github.com/rust-lang/crates.io-index)" = "ecd45702f76d6d3c75a80564378ae228a85f0b59d2f3ed43c91b4a69eb2ebfc5"
 "checksum proc-macro-nested 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "369a6ed065f249a159e06c45752c780bda2fb53c995718f9e484d08daa9eb42e"
 "checksum proc-macro2 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "9c9e470a8dc4aeae2dee2f335e8f533e2d4b347e1434e5671afc49b054592f27"
diff --git a/Cargo.toml b/Cargo.toml
index 4bf926e..a478d3d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,6 @@ log = "^0.4.8"
 num-bigint = "^0.2.6"
 num-traits = "^0.2.11"
 num_cpus = "^1.13.0"
-png = "0.16.3"
+png = "0.16.7"
 threadpool = "^1.8.0"