Presentation Recording

Use the RTD1295 based Zidoo X8 / X9s to record any incoming HDMI to USB and broadcast via network (UDP, TS, H264).

The idea is to automatically capture any input to a USB stick. The main use case is in a presentation scenario to simply grab all presented content.

The Zidoo X8 and x9s are cheap devices (100 USD / 150 USD) and can capture 4k and 1080p HDMI input as H264 and also sent the input as UDP stream to a network. Both features are normally features of quite expensive hardware.

Getting Started

This will describe how to setup a Zidoo X8 or X9s for remote debugging and install the software. The APK is in the subfolder release.

Install steps

1. RTD1295 based Android box. Tested with Zidoo X8 and Zidoo X9s.
2. Upgrade firmware to version 1.4.12
3. Root the device
4. Install SSH server. I am using SSHelper.
   • I have the following settings
     • Run SSHelper service at boot = Yes
     • Check Network connectivity = No
     • Allow voice messages = No
5. (optional) Install BusyBox. Very helpful for local task on the device in the shell.
6. SSH onto the device and activate remote debugging.

su
setprop service.adb.tcp.port 5555
stop adbd
start adbd

7. From the local computer start adb session.

adb connect <IP address>:5555

8. The application can now be developed from the Android Studio.
9. The application must be deployed as system application. I was not able to write the recorded file onto the USB stick without system permissions.

adb push net.schmidtie.PresentationRecording.apk /sdcard/
adb shell
	su
	mount -o rw,remount /system
	mv /sdcard/net.schmidtie.PresentationRecording.apk /system/priv-app/
	chmod 644 /system/priv-app/net.schmidtie.PresentationRecording.apk

	am broadcast android.intent.action.ACTION_SHUTDOWN && sleep 5 && reboot -p

The installation is done by USB stick. I copy the image and all APK onto a stick.

Issues

The following steps helped me to resolve HDMI glowing issues:

• Change HDMI cable.
• Adjust settings on Zidoo Box.
  • Picture Settings => Constract form 32 increase to 36

The following steps helped me to resolve fuzzy HDMI output:

• Change HDMI input resolution to 1920x1080.

Streaming over WIFI:

• Using a LEDE (OpenWRT) WIFI AP and add the following setting:
  • In "/etc/config/wireless" add to the AP "option isolate '1'".
  • See Wifi configuration for details.

Measurements

I have measued the display delay when using the Zidoo Box. The following measurements are an average of 5 measurements:

GoPro -(HDMI)-> TV
   163ms
GoPro -(HDMI)-> Zidoo -(HDMI)-> TV
   216ms
GoPro -(HDMI)-> Zidoo -(UDP)--> VLC (:network-caching=250)
   485ms
GoPro -(HDMI)-> Zidoo -(UDP)--> VLC (:network-caching=1000)
  1218ms

VLC network cache below 250ms was not working.

The computer running VLC used a USB 3.0 Gigabit network adapter.

Internals

Hardware

See Teardown folder for pictures.

• Zidoo X8 and X9s use the same mainboard. The Zidoo X8 board is marked on the PCB as X9s.
• Connector on board marked with 3.3V, TX, RX, GND (UART) betwen USB3 and SATA port.
• Power supply:
  • Zidoo X8 marked with 12V 1.5A
  • Zidoo X9s marked with 12V 3A. The additional 1.5A must be for the SATA disk.
• Zidoo X8 board is mounted upside down on the top of the case. On the base is a weight of 45g. Removing it reduces the total weight from 315g to 270g.
• Zidoo X9s weight is 430g due to the metal case.
• WI-FI:
  • Zidoo X8 one internal fixed and one external fixed Antenna.
  • Zidoo X9s two external detachable Antenna.
  • Antennas connected to PCB via u.fl(?) connector.
  • Chip RTL8821AU (1x1 ac)

UART

See file Zidoo X8 bootlog.txt. OpenWRT console on UART after startup.

Zidoo Online Updater

Source Urls:

• China
  • http://oldota.zidootv.com/index.php?m=Ota
• World
  • http://ota.zidoo.tv/index.php?m=Ota
  • http://ota.zidootv.com/index.php?m=Ota

Submitted information are:

• Mac address
• current Firmware version
• Model name
• Language

Example Url:

http://ota.zidoo.tv/index.php?m=Ota&mac=FF:FF:FF:FF:FF:FF&firmware=1.4.2&model=ZIDOO%20X9S&lang=en

Image is then downladed to /cache/onlineupdate.zip