diff --git a/vnrecode/params.py b/vnrecode/params.py
index 552036c..a20e9ce 100644
--- a/vnrecode/params.py
+++ b/vnrecode/params.py
@@ -96,17 +96,17 @@ class Params:
         parser.add_argument("-nm", "--no-mimic", dest='mimic', action='store_false', help="Disable mimic mode")
         parser.add_argument("-v", "--show_errors", action='store_false', help="Show recode errors")
         parser.add_argument("--webp-rgb", dest='webp_rgba', action='store_false', help="Recode .webp without alpha channel")
-        parser.add_argument("-j", "--jobs", type=int, help="Number of threads", default=16)
-        parser.add_argument("-ae", dest="a_ext", help="Audio extension", default="opus")
-        parser.add_argument("-ab", dest="a_bit", help="Audio bit rate", default="128k")
-        parser.add_argument("-id", dest="i_down", type=int, help="Image resolution downscale multiplier", default=1)
-        parser.add_argument("-ie", dest="i_ext", help="Image extension", default="avif")
-        parser.add_argument("-ife", dest="i_fallext", help="Image fallback extension", default="webp")
+        parser.add_argument("-j", "--jobs", type=int, help="Number of threads (default: 16)", default=16)
+        parser.add_argument("-ae", dest="a_ext", help="Audio extension (default: opus)", default="opus")
+        parser.add_argument("-ab", dest="a_bit", help="Audio bit rate (default: 128k)", default="128k")
+        parser.add_argument("-id", dest="i_down", type=int, help="Image resolution downscale multiplier (default: 1)", default=1)
+        parser.add_argument("-ie", dest="i_ext", help="Image extension (default: avif)", default="avif")
+        parser.add_argument("-ife", dest="i_fallext", help="Image fallback extension (default: webp)", default="webp")
         parser.add_argument("-il", dest='i_lossless', action='store_false', help="Image losing compression mode")
-        parser.add_argument("-iq", dest="i_quality", type=int, help="Image quality", default=100)
-        parser.add_argument("--v_crf", help="Video CRF number", type=int, default=27)
+        parser.add_argument("-iq", dest="i_quality", type=int, help="Image quality (default: 100)", default=100)
+        parser.add_argument("--v_crf", help="Video CRF number (default: 27)", type=int, default=27)
         parser.add_argument("-vs", dest="v_skip", action='store_true', help="Skip video recoding")
-        parser.add_argument("-ve", dest="v_ext", help="Video extension", default="webm")
-        parser.add_argument("-vc", dest="v_codec", help="Video codec name", default="libvpx-vp9")
+        parser.add_argument("-ve", dest="v_ext", help="Video extension (default: webm)", default="webm")
+        parser.add_argument("-vc", dest="v_codec", help="Video codec name (default: libvpx-vp9)", default="libvpx-vp9")
         args = parser.parse_args()
         return args
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