By Cameron Wright, Contributor TDG Online
It seems that a “critical feature” in existing and upcoming Android handsets is HDMI out. We crave it, slam phones that don’t have it, and will spend absurd amounts on cable to connect these devices to our Televisions. Or do we? Welcome to a three part series regarding HDMI out on Android phones. This first article focuses on the Evo 4G a phone that I’ve been using for nearly three months now and have a deep understanding of. When I first heard about the Evo 4G it shot up to the number one spot in my list of desired phones. The top three reasons, 4.3 inch screen, 4G, and HDMI out. This phone was going to be a game changer. All I could want in one phone. Out of those three reasons only two have lived up to their hype. The screen and the 4G. It turns out HDMI out wasn’t quite what I had envisioned.
The Evo has two ports at the bottom of it micro USB and micro HDMI. Since the Droid Incredible had just been showcased with full screen sharing (and dual-view) via video out, I was assuming that the same option would be available via HDMI. It ended up not being the case. Out of the box it is not system-wide out, in fact you can only use the HDMI out for videos and pictures that you have taken with your phone. On top of that the Evo has limitations on it’s frames per second (fps) generally being held to about 30 fps. HTC stated that the reason that the fps was capped at 30 is because most televisions have a limit of 24 fps.
- In Part Two – Droid X HDMI out – We’re doing it wrong
- Part Three – HDMI out – We’re doing it wrong Right
- GL Benchmark Image via AndroidandMe
- HDMI – High Definition Multimedia Out
- Dual-View – ability to view content on the phone screen and at the same time on your HDTV
- FPS – Frames Per Second from wikipedia Frame rate, or frame frequency, is the frequency (rate) at which an imaging device produces unique consecutive images called frames.
- Kernel – The central component of most operating systems. Its responsibilities include managing the system’s resources (the communication between hardware and software components) and can provide the lowest-level abstraction layer for resources (especially memory, processors, and I/O devices)
Evo 4G is capped as shown by the image above from GLBenchmark results.
Romain Guy, an Android framework engineer posted on the Developers forum, “It is certainly not the goal of the Android team to ship devices locked at 30 FPS. Our target was, is and will be 60 FPS.” Personally, I don’t have a problem limiting fps when HDMI is being used but seeing as HDMI is not being used more than 90% of the time it was just poorly implemented. Over at XDA they have solved the issue of the fps cap, and did so months ago. This requires users to root their phones and install a custom rom and kernel. While not necessarily the best solution for all, it is a solution. Official responses regarding the frames per second issue from HTC support staff via email to members posting on the HTC forums have ranged from 1) we know of the problem and are investigating it 2) to it’s a hardware issue or 3) it’s a software issue. In other words, it seems as if there is a bit of a run around. When the Evo 4G was originally released HTC made it sound as if they were working feverishly to find a solution to the HDMI out issues. But as time has passed the urgency seems to have left them. It is possible that at some point in the future there will be an official solution which opens up both the frame rate and HDMI output. Unfortunately as of right now it does not look very likely.
Posted by Freddy_ace
Since I said I’d post HTC’s reply:
Got an email back from Sarah:
“Hi Fredy, Thank you for your reply. Since the HTC EVO 4G employs a unique HDMI output to deliver video in HD quality to an external display, the hardware graphics driver interface on the HTC EVO 4G uses significant resources for the HDMI output and therefore displays graphics at 30 frames per second on the integrated display. This is a hardware, and not a software, limitation. It’s important to keep in mind that content including most movies and television, are created to run at between 24 and 30 frames per second. The 30FPS is a hardware limitation, and cannot be changed.
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Posted by joek71
I just got email from HTC:
Hi, I am Danielle and I would be happy to assist you today. You were wondering about the cap on 30 FPS on your HTC EVO 4G. Since this Android device employs a unique HDMI output to deliver video in HD quality to an external display, the hardware graphics driver interface uses significant resources for the HDMI output and therefore displays graphics at 30 frames per second on the integrated display. It’s important to keep in mind that content including most movies and television, are created to run at between 24 and 30 frames per second. We have found that some games may be impacted by this limitation. The HTC EVO 4G has been locked to 30 FPS. This should not present a major issue for most Android applications; however, you may have some issues with some 2D or 3D applications. The 30 FPS has been locked to enhance overall performance in the device. By lowering the FPS of the device the CPU works less. This increases the battery life of the device. The 30 FPS is set but we have decided to look into the possibility of overcoming this limitation by software changes. HTC plans to announce its findings when we complete our investigation. I thank you for contacting HTC and please feel free to send another email if you have any other questions.
We have to stay on top of these guys and hopefully they will come out with firmware patch to fix this.
As of September 11, 2010 nobody has found a way to implement full HDMI out. The team over at Cyanogenmod have been busy hard at work trying to crack the mystery of how to offer the full HDMI experience with Direct Draw and Dual-View capabilities. Hopefully this will allow you to see the same images on the TV and your phone simultaneously. We reached out the the team and found out some information, it is nothing earth shattering or exclusive. In the final part of the series I will be sharing all the current information on solutions.
In Part Two – Droid X HDMI out – We’re doing it wrong
I will focus on the limitations found in the Motorola Droid X and it’s HDMI output limitations, in comparison to the existing market of capable devices, and their supposed functionality.
Part Three – HDMI out – We’re doing it wrong Right
The final part of this series will focus on the headway that has been made in addressing these flaws and what solutions are tentatively on the horizon for both phones, and the dev communities that are working to provide solutions!