Digital zoom not working with HDMI/USB-C source

As title, digital zoom is not working with HDMI input. Internal source is working fine.
Is this a bug?

Hi Lun,

This is not a Bug, but a hardware limitation. Digital Zoom only works on internal content via Android like Netflix and Youtube

Just the same as 4 corner correction and bluetooth connection with HDMI.

Correct, its the same thing. HDMI and USB C inputs are send directly to the video processor/chip, so android can not do things like 4 corner correction or bluetooth audio.

move the source… its a mobile projector.

That is always the best option:)

The V56 video processor has the overscan scaler with the possibility to enlarge the image (which is typically enabled in LCD TVs using that chip). Isn’t there a possibility to have a negative overscan setting (underscan) basically turning it into the PPM digital zoom feature? Do you have the complete Mstar documentation @prashant?

1 Like

Indeed, even if complete geometry adjustment isn’t possible for HDMI, having at least the zoom would be quite useful.

2 Likes

I think so too, even though I’ll always prefer 1:1 pixel mapping no matter what (and that includes the digital v keystone correction, a feature I just HAVE to disable). The only time keystone correction actually worked for me was on the ancient CRT projectors (like these: BarcoData 708 - Barco), but I certainly don’t miss the convergence setup!

But yes, for the quick portable use-case the PPM is designed for the digital zoom is most definitely a useful feature.

I wouldn’t had to ask if that is a solution. Neither want to hold the PPM in the middle of my bed, nor hang it from the ceiling. The digital zoom function is there for a reason.

100% aggree

The service menu of the V56-based LCD TV I have here for experimentation does not allow me to set a negative overscan so there’s no proof yet that the chip can do it.

As the username was changed between this post was deleted and then later restored it seems like the mention isn’t linking, so I’m linking it again: @PhilipsEngineering Has Mstar provided your team with complete documentation? It would be very interesting to see if the V56 will allow a negative overscan to be set.


On Indiegogo story page, Philips now explicitly remarked that 4 corner correction is for internal content only and not working with hdmi. Description for the digital zoom function just right above there didn’t say hdmi not work though. If this is not another lie, there’s still hope they can fix it.

Actually I posted the problem on IGG 2 weeks ago. Philips said they are on it. I just asked for an update yesterday with no reply yet. Let’s see how they have to say. Fingers crossed. https://www.indiegogo.com/projects/philips-picopix-max-1080p-full-hd-pico-projector/x/22305159#/comments?id=8930305

Yes, originally the marketing story had 50-100% digital zoom and no source restrictions mentioned. When this was called out after initial reviews the story was updated which caused a lot of discussion. The negative overscan idea above is just an idea with no confirmation whether it’s possible or not. 4-corner on hdmi is 100% out though.

@PhilipsEngineering @PhilipsNono
Comment section in Indiegogo has officially dead. Please provide answer here. Thx!

Hi @Lun,

All the features are available for internal content (Android system).

For external content (HDMI and USB-C inputs), only the following correction is available:

  • automatic vertical keystone correction (up/down tilt)

The following features are not available for HDMI and USB-C inputs:

  • 4-corner correction
  • digital zoom
  • Bluetooth audio playback

This is a hardware limitation and a firmware update will not be able to fix it.

Very sad to hear about it!

We are too :frowning_face: Too many of our customers want this feature.

This is very frustrating. It never occurred to me that a projector would not be able to adjust the display size. I really like the projector but this limitation is almost so severe that it makes me consider asking for a refund.