diff --git a/.gitignore b/.gitignore
index c85394a..64c9d74 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ bindings/generated
 *.dSYM
 dump.txt
 tests/fileformats/jpeg/generated
+tests/fileformats/jpeg/diff
diff --git a/tests/benchmark_jpeg.nim b/tests/benchmark_jpeg.nim
index 0558438..498e691 100644
--- a/tests/benchmark_jpeg.nim
+++ b/tests/benchmark_jpeg.nim
@@ -24,6 +24,7 @@ var files = @[
   "tests/fileformats/jpeg/master/cat_4_2_2.jpg",
   "tests/fileformats/jpeg/master/cat_4_2_0.jpg",
   "tests/fileformats/jpeg/master/cat_4_1_1.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_0_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_4_4_4_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5_progressive.jpg",
diff --git a/tests/fuzz_jpeg.nim b/tests/fuzz_jpeg.nim
index 3f9d7a8..248ab56 100644
--- a/tests/fuzz_jpeg.nim
+++ b/tests/fuzz_jpeg.nim
@@ -26,6 +26,7 @@ var files = @[
   "tests/fileformats/jpeg/master/cat_4_2_2.jpg",
   "tests/fileformats/jpeg/master/cat_4_2_0.jpg",
   "tests/fileformats/jpeg/master/cat_4_1_1.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_0_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_4_4_4_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5_progressive.jpg",
diff --git a/tests/test_jpeg.nim b/tests/test_jpeg.nim
index de65564..93b8e45 100644
--- a/tests/test_jpeg.nim
+++ b/tests/test_jpeg.nim
@@ -26,6 +26,7 @@ var files = @[
   "tests/fileformats/jpeg/master/cat_4_2_2.jpg",
   "tests/fileformats/jpeg/master/cat_4_2_0.jpg",
   "tests/fileformats/jpeg/master/cat_4_1_1.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_0_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_4_4_4_progressive.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5.jpg",
   "tests/fileformats/jpeg/master/cat_restart_markers_5_progressive.jpg",
diff --git a/tests/validate_jpeg.nim b/tests/validate_jpeg.nim
index b37d018..f3f5647 100644
--- a/tests/validate_jpeg.nim
+++ b/tests/validate_jpeg.nim
@@ -1,3 +1,60 @@
-import pixie/fileformats/jpg, pixie/fileformats/stb_image/stb_image
+import pixie, strutils, os, strformat
 
-let original = readFile("tests/fileformats/jpeg/jpeg420exif.jpg")
+import pixie/fileformats/jpg
+
+var files = @[
+  "tests/fileformats/jpeg/master/red.jpg",
+  "tests/fileformats/jpeg/master/green.jpg",
+  "tests/fileformats/jpeg/master/blue.jpg",
+  "tests/fileformats/jpeg/master/white.jpg",
+  "tests/fileformats/jpeg/master/black.jpg",
+
+  "tests/fileformats/jpeg/master/8x8.jpg",
+  "tests/fileformats/jpeg/master/8x8_progressive.jpg",
+
+  "tests/fileformats/jpeg/master/16x16.jpg",
+  "tests/fileformats/jpeg/master/16x16_progressive.jpg",
+
+  "tests/fileformats/jpeg/master/quality_01.jpg",
+  "tests/fileformats/jpeg/master/quality_10.jpg",
+  "tests/fileformats/jpeg/master/quality_25.jpg",
+  "tests/fileformats/jpeg/master/quality_50.jpg",
+  "tests/fileformats/jpeg/master/quality_100.jpg",
+
+  "tests/fileformats/jpeg/master/cat_4_4_4.jpg",
+  "tests/fileformats/jpeg/master/cat_4_4_4.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_2.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_0.jpg",
+  "tests/fileformats/jpeg/master/cat_4_1_1.jpg",
+  "tests/fileformats/jpeg/master/cat_4_2_0_progressive.jpg",
+  "tests/fileformats/jpeg/master/cat_4_4_4_progressive.jpg",
+  "tests/fileformats/jpeg/master/cat_restart_markers_5.jpg",
+  "tests/fileformats/jpeg/master/cat_restart_markers_5_progressive.jpg",
+
+  "tests/fileformats/jpeg/master/mandrill.jpg",
+  "tests/fileformats/jpeg/master/exif_overrun.jpg",
+  "tests/fileformats/jpeg/master/grayscale_test.jpg",
+  "tests/fileformats/jpeg/master/progressive.jpg",
+
+  "tests/fileformats/jpeg/master/testimg.jpg",
+  "tests/fileformats/jpeg/master/testimgp.jpg",
+  "tests/fileformats/jpeg/master/testorig.jpg",
+  "tests/fileformats/jpeg/master/testprog.jpg",
+]
+
+for file in files:
+  var img = decodeJpg(readFile(file))
+
+  let genFile = file.replace("master", "generated").replace(".jpg", ".png")
+  let diffFile = file.replace("master", "diff").replace(".jpg", ".png")
+
+  if execShellCmd(&"convert {file} {genFile}") != 0:
+    echo "fail"
+
+  var img2 = readImage(genFile)
+  let (score, diff) = img2.diff(img)
+  diff.writeFile(diffFile)
+
+  if score > 1:
+    echo "!!!!!!!!!!!!!! FAIL !!!!!!!!!!!!!"
+  echo &"{score:2.3f}% ... {file}"