I’m due to receive my VIM4 tomorrow and have a specific application in mind. I want to use the VIM4 in-between my STB and TV. I want to try and implement a better smart home solution than provided by the dissapointing Fire TV cube. This will include displaying information from home assistant, providing an Alexa interface, and showing home security cameras. The requirement is that my graphical interface is always shown overlaid on top of the STB video (up to 4K60).
I would like the VIM4 to take the HDMI from HDMI_IN, add the overlay and output it to the TV. Ideally, audio and video is passed unmodified except for mixing my overlay and, ideally, audio (sound effects) if thats possible. If the VIM4 could upscale anything less than 4K60, even better.
I believe I will have HDCP issues with the output of the STB but I think I have a solution for that.
Is there any example code that implements this? I have seen reference to the HDMI demo code but as I have yet to receive the HW, I’m not tried anything.
Thanks @Electr1, it would be great to get some ideas from your experts.
I’ve received my board and have tried both Ubuntu hdmiin-demo and Android 11.
The Android 11 build is interesting - I managed to watch a movie from Apple TV (set to 4K) and the HDMI in of Android reported the input video as 4K. The video window had the icon buttons along the bottom of the screen, and could overlay volume settings. I think this shows that what I want to do is possible (i.e. have an input video signal and overlay graphics)? Interesting that HDCP content was also displayed? I don’t know how to check but, the image quality didn’t look like 4K and the blacks/dark colours looked blocky. I’d need to investigate more but, can you tell me what resolution the HMDI in works at for Android? Is it up to 4K60?
@mph070770 The resolution and frame rate of HDMI-IN are displayed here. HDMI-IN needs to support input of 4K 60Hz. It needs to apply for copyright and burn the key of RX 2.2 in the board.
Can you play that video directly on VIM4 and see what the comparison effect looks like?
Thanks @goenjoy. I don’t fully understand your reply. The banner (3840x2160) is displaying the incoming format of the signal on HDMI_IN, or what the Android window is displaying, or both? Does Android perform any scaling?
Could you also explain further your comment:
“It needs to apply for copyright and burn the key of RX 2.2 in the board.”
Are you saying the keys are in the Android build, or not?
The banner (3840x2160) is displaying the incoming format of the signal on HDMI_IN==yes
It should be necessary to pay to apply for a key from amlogic and then burn the key into the CPU.
When we first debugged the HDMI-IN of VIM4, we found that we couldn’t reach it 4K@60fps . The response obtained from consulting with amlogic. Due to the need to apply for a key from amlogic through business, there was no verification.
Thanks @goenjoy, so at the moment, without a key, it’s likely that I’m getting a scaled image, not 4K, and this is because of HDCP copy protection? The banner is reporting the input signal format, but Android is then scaling this down to, say, HD definition? Sorry to labor this point but I’m just trying to understand exactly what should happen.
OK, understood on the video test. I was playing original content from Apple TV so I can’t play this directly on the VIM4. I’ll do another test where i can play a file on the Apple TV, and then on the VIM4.
Thanks for your continued support.
