A picture is worth a thousand words. That’s a well known saying. And in Android, pictures are used to show your home screen, developments in progress, or simply demonstrate an error. The ability to take screenshots was implemented into stock Android a long time ago, but grabbing a screenshot while in recovery is still quite problematic. You can try to use the monitor tool from Android SDK, but it doesn’t always work right.
Luckily, there is a workaround for almost every issue, and XDA is a great place to find the answer. XDA Forum Member makers_mark created a tool to grab snapshots from recovery and Aroma installer. This tool uses FFmpeg for screen capture without frame buffer problems. And except the required ADB and FFmpeg libraries, a batch script takes care of all the magic.
This tool should work with all recoveries, so you can easily show off your TWRP themes or fix problems with your updater-script. The only disadvantage of this tool is that it only works with Windows. And of course, to run it properly, your phone needs to have ADB enabled.
You can find more information about this tool by visiting the original thread. So if you want to make a screenshot while in recovery, give this tool a shot._________