Microsoft forced HTC to downgrade color palette to 16bit on Windows Phone 7 handsets ?

A Microsoft support contractor/employee posted earlier this week that the color banding issue experienced by HTC users after the firmware update that came along side NoDo update was the result of Microsoft’s decision to force HTC to downgrade their device’s color depth to 16bit because it was apparently set to 32bit before. Let’s just say that I have some serious doubts about this claim. Anyway, here’s the full statement:


When HTC launched the HD7 and Trophy they upgraded the color depth to 32 bit, which was outside of Microsoft’s design requirements of 16bit. Microsoft implemented the design standards to help ensure the best possible and consistent experience for all customers on all Windows Phones. To continue to deliver a stable and consistent customer experience, HTC returned the devices to the 16 bit design requirements as part of the March (7.0.7390) update.

The color palette change should not make a noticeable change to most customers experience on their Windows Phone 7. Microsoft’s goal is to ensure that the device is performing as optimally as possible – and as always their engineering teams continue to investigate the opportunities for future improvements.

Thank you for your contribution to the forums.

First, let me just say that the 16bit color depth requirement in WP7 is true. Only Mango will allow third-party applications to run in 32bit if the developer decides to force it. Now my issue with this whole situation is that forcing the OS to run in 32bit (via the registry) results in a serious performance hit. I invite anyone who claims that this isn’t the case to shoot a before and after video to see the difference. I’ve done it on an Omnia 7 & a friends HTC 7 Trophy. Both device’s take a nose dive in terms framerate, especially in third party apps. Before the NoDo update HTC’s devices didn’t exhibit any banding and performed without any performance issues as you can see in the the video after the break:

Secondly why didn’t LG get forced to do the same on the Optimus 7 and Quantum with NoDo? Both devices don’t have any banding issues and perform just as well as any other device. I doubt that HTC was and LG is still forcing 24 Bit or 32bit rendering throughout the OS…or they will have to explain to me how they magically did it without any performance hit. So, there’s definitely something else going on here and my guess is that proper 16bit to 24bit dithering seems to have been disabled on HTC’s devices just like on Samsung’s.

source: Microsoft via smfrance

  • Keepitrealxs

    I dont get this so what does the 32bit slow down your device ore what i would like to change mine to 32 bits to remove the color banding on my Omnia 7

  • MobileTechWorld

    What ? Anyway… You can force 32/24bit rendering in some parts of the OS (not IE Mobile or XNA apps for example) via the registry if you have a developer unlocked device. But the performance hit in 3rd party apps and the home screen (if it’s packed with live tiles) isn’t worth it IMO.
    In the case of the Omnia 7 this will “fix” most of the banding but not everything because the Super AMOLED panel will still showcase some slight banding in a few places compared to regular RGB displays.

  • Keepitrealxs

    you didn’t have to say what because you did understand my question perfectly. Anyway thank you for responding to my question. PS could you tell me where to go in the registry to change it and i am aware of the risks and so on

  • MobileTechWorld

    Seriously, your first post didn’t make much sense..there’s no punctuation for example… :)

    You will have create the following entries:
    HKLMDriversDisplayPrimaryPrimBPP dword
    HKLMDriversDisplayPrimarybpp dword
    HKLMDriversDisplayPrimaryPanelBPP dword 24

    But like I said this isn’t a real “fix”. The issue isn’t 32bit vs 16bit it’s a total lack of proper 16bit color dithering on the Samsung and now HTC devices.

  • Keepitrealxs

    You sound just like my teacher :P , thank you for your help