Update README.md

README.md

@@ -14,7 +14,7 @@ Using it you can:
 - automatically fix color differences
 - view MCU pixel levels, coefficients, and binary data-stream
 
-Controls:
+## Controls
 
 - **mouse wheel** → zoom image
 - **left click** → select MCU; a black or white rectangle appears on selected MCU
@@ -24,13 +24,25 @@ Controls:
 - **right button drag** → extend selection for color fixing
 - **ctrl-c** → copy selected MCUs
 - **ctrl-v** → paste before selected MCU
+- **ctrl-z** → undo last operation
 - **arrows** → change selected MCU
 - **i** → open MCU info dialog
+- **s** → shift MCU rendering using left/right keys
 - **del** → delete MCU
 - **1-2-3-4** → change view (RGB, Y, Cb, Cr)
 
 A crossed red rectangle appears on MCUs that produced decode errors.
 
 **Limitations:** no support for progressive scans or arithmetic encoding.
 
-For more details see the [tutorial](RepairingCorruptedJpeg-JVRT.pdf) 
+## Quick start
+
+corrupted images can be edited block by block (MCU) without losing information; even bright or dark areas still contain the original details. The problem often lies in the DC levels of specific MCUs.
+
+First align image features by deleting spurious MCUs (effect of corruption); the shift feature (s+arrows) comes handy in determining how many blocks to delete.
+
+Equalize colors either manually (DC+/DC- while viewing a single channel) or automatically (using __Fix colors__ on right-selected MCUs)
+
+Finally, save as a new image
+
+For more details see the tutorial on [how to repair a corrupted image](RepairingCorruptedJpeg-JVRT.pdf)