Success- Modifying Reverse Camera Guidelines

I just show the Samarth methods for changing the guidelines, You also can check the RAV4 forums link. He got this android head unit RAV4

Samarth feedback to us, I was successful in rooting and changing the guidelines. I have posted instructions on how to change camera guide lines on RAV4World forums in the post below:

http://www.rav4world.com/forums/1910761-post9.html

I have found a temporary solution which should work for me:

-          I followed the guide posted on Joying After-sale support blog about how to root with RK3188 1024x600 Malaysk ROM

-          After rooting I have root access to ..system\app\MTCBackView.apk\res\drawable-nodpi\bg_distance.png

-          The attached “bg_distance.png” has the ruler. I will draw a ruler that for my camera setup and replace this png image file which should work for my setup.

　

Thank you for forwarding feedback to engineers. Since rooting is not best solution for everyone, maybe future joying update can have option to select user image for guidelines instead of bg_distance.png.

Ok, so I was successful in modding the reverse camera guidelines on the android unit. I will summarize the main steps and would be happy to elaborate on any step if needed. Hopefully, this will be useful for owners of any variant of RAV4 specific Android Head unit. Even though there is little room for screwing up, proceed with caution at your own risk (I won't be responsible if you brick your unit)

1. Root the unit to be able to modify the reverse view system app (MTCBackView.apk) that imposes guide lines. For quad core units variants running Android 4.4.4, I believe the only way to root is by upgrading to a pre-rooted ROM. I used the latest MALAYSK ROM found here:
FileMirror for HuiFei-Units
There should be a custom ROM for each of the 4 hardware variants. Make sure you choose right one for your hardware or else you will brick your unit. At first I upgraded to the Malaysk ROM that features Next Launcher because it sounded cool. However, I found the interface a bit confusing so I switched to the Malaysk ROM without Next Launcher. The latter ROM was surprisingly almost identical interface to the original software interface. This is good for anyone who is worried about drastically changing the way their unit operates. Most of the previous settings are retained and the extra features are nicely tucked in system settings. For anyone needing info about how to upgrade the ROM, scroll down to the instructions outlined at the bottom of the following page:
Joying® Aftermarket Best Android Head Unit, Android Car Stereo, Android Car Radio Audio How to Root Joying Android car stereo Radio head unit ways and methods Android In-Dash Android GPS navigation | carjoying.com
If you were unsure whether rooting was succesful, there are may root checker apps that you can install from play store to verify root.

2. Next step is to access the "MTCBackView.apk" app. The Malaysk ROM comes with a root explorer that is capable of reading and writing to the root. If you used any other root method, make sure you have a file explorer app that can access root. Navigate to root/system/app/ and find the file called "MTCBackView.apk". Copy this file to removable media such as SD or USB.
Check out the attachment "MTCBackView in root.jpg" for picture steps.

3. Transfer the apk file from removable media to your computer. Open up the apk file using WinRAR. WinRAR is a free software in case you do not already have it. Once open, go into res\drawable-nodpi\ and find an image file called "bg_distance.png" This is the ruler overlay image. Extract/copy this image onto another location on your computer. Check out the "Extract Guide Lines Image.PNG" for picture steps. For reference, I have also attached the original overlay image as "bg_distance(orig).png"

4. Now we shall may modify bg_distnace.png to show the guidelines appropriate for the installed camera. The image resolution, file name, png format and image transparency must be retained. For modifications, I used Paint.NET, a free software similar to Adobe Photoshop that allows working with layers. For calibration purposes, I laid makeshift guides on the road after parallel parking tight to a curb on driver side. I used a wardrobe shelf that was just above 2m long and laid it parallel to the curb and vehicle alone the center line. I also unscrewed the rods of two mops that I laid on driver side to mirror passenger side lines. I used a random block to mark the 0.5 meter location. The resulting image can be seen in the attachment "calibration1.jpg". I used the calibration image to draw my own lines in Paint.NET and saved the resulting "bg_distance.png" (attached). This modified image file can now be copied and pasted into WinRAR to replace the original image. Close WinRAR to finish updating MTCBackView.apk.

5. Transfer the update "MTCBackView.apk" to removable media to load onto the head unit. Now root explorer can be used to copy this file from external storage and paste to replace the original file in root\system\app\. Once this step is completed, reboot the device for changes to take effect. The attached file "guidelinesmodified.jpg" shows my final results. As can be seen, I chose to include distance markers because the optics of my camera make it difficult to judge distances correctly. Also, my camera is not exactly centered, so a centerline seemed necessary.