[Auzo]

I am having a couple of problems with the MHL adapter:
One issue with the MHL adapter is that when connected it cuts off audio bluetooth transmission to my stereo. Really annoying as want to use my computer monitor as the HDMI device and my stereo for audio.
Another issue is that the image on the computer monitor is very unsharp despite the HDMI connection because the native resolution of the monitor does not match that of the SG3. Maybe by installing ubuntu on the SG3 it is possible to drive the computer monitor in its native resolution. Has anyone tried it?

For the first part I think that's inherent to how HDMI is set up. The content providers decided, in their great wisdom, that they wanted the ability to add content protection (HDCP). This allows them to prevent video or audio from being transmitted in any method other than directly through HDMI and would require a properly certified "receiver" as well.


I thought it was determined on an app by app basis (if developer enables content protection), but if it happens instantly after plugging in your MHL cable regardless of what app you are using then it may just be globally applied content protection at the OS level.

For the second part, I'm not sure it would make much of a difference. The reason being that there is an up-conversion that is happening somewhere and I'm not sure having your phone do it vs your monitor internal circuitry would improve things much. For example if I set my monitor to its native resolution of 2560x1440 and then input a 1080p source into it, it will not change my monitors resolution to 1920x1080 instead it will take the source signal and up-convert it to my native resolution. Alternatively if I did what you suggest the phone would take the 1080p source material then up-convert it and output a 2560x1440 resolution signal and my monitor wouldn't have to do anything more at that point. In either case I would expect the quality to be similar.

The problem could be somewhere else though. For example I think that the Netflix app never actually goes up to 1080p (because up until recently no phones even had that resolution) so even if i hooked it up to a TV it would still never look as good as if i watched Netflix directly on my TV. I'm not sure if that's the case with the Netflix app anymore, but that was just for example.

Just curious, what is the source you are trying to display on your monitor?

[Bo Martins]

For the first part I think that's inherent to how HDMI is set up. The content providers decided, in their great wisdom, that they wanted the ability to add content protection (HDCP). This allows them to prevent video or audio from being transmitted in any method other than directly through HDMI and would require a properly certified "receiver" as well.


I thought it was determined on an app by app basis (if developer enables content protection), but if it happens instantly after plugging in your MHL cable regardless of what app you are using then it may just be globally applied content protection at the OS level.

For the second part, I'm not sure it would make much of a difference. The reason being that there is an up-conversion that is happening somewhere and I'm not sure having your phone do it vs your monitor internal circuitry would improve things much. For example if I set my monitor to its native resolution of 2560x1440 and then input a 1080p source into it, it will not change my monitors resolution to 1920x1080 instead it will take the source signal and up-convert it to my native resolution. Alternatively if I did what you suggest the phone would take the 1080p source material then up-convert it and output a 2560x1440 resolution signal and my monitor wouldn't have to do anything more at that point. In either case I would expect the quality to be similar.

The problem could be somewhere else though. For example I think that the Netflix app never actually goes up to 1080p (because up until recently no phones even had that resolution) so even if i hooked it up to a TV it would still never look as good as if i watched Netflix directly on my TV. I'm not sure if that's the case with the Netflix app anymore, but that was just for example.

Just curious, what is the source you are trying to display on your monitor?

Hi Auzo.

Thank you for trying to help. It is much appreciated.

For the first part, I was running youtube and the audio was cut off upon plugging in the MHL adapter and the audio returned immediately upon unplugging it. I cannot believe though that muting the audio is a matter of content protection. It seems more likely to me that Samsung has tried to guess that the display device is a TV and therefore chooses to route the audio to the TV as well.

For the second part, I was just running the internet app. The resolution of my monitor is 1920x1280 and that of the SG3 is 1280x720. I am hoping that I can force the system to use the resolution 1920x1280 so that the automatic conversion you are talking about will not happen. My next problem is that I don't know what will happen if I try to drive the phone display at that resolution. Will the phone cease to work or will the phone display just look bad. The latter case would work for me as I would use a USB hub with keyboard and mouse as input devices when the MHL connector were attached. But I *am* a little bit concerned that I have not seen any post on the web saying something like "I am running Ubuntu on my SG3 with a external HDMI monitor and everything works like a peach".

[Suntan]

I've had both instances, depending on the TV.

On some TVs I get a 1280x720 output that has rather jumbled up aspect ratios (I blame the TV.) On a different brand I have had it sync at 1080p with correct aspect ratio and minimal overscan.

In both instances, the phone display continues to display normally.

This is with the newer Samsung MHL adapter that is specifically for the GSIII.

-Suntan

[Auzo]

Hi Auzo.

Thank you for trying to help. It is much appreciated.

For the first part, I was running youtube and the audio was cut off upon plugging in the MHL adapter and the audio returned immediately upon unplugging it. I cannot believe though that muting the audio is a matter of content protection. It seems more likely to me that Samsung has tried to guess that the display device is a TV and therefore chooses to route the audio to the TV as well.

For the second part, I was just running the internet app. The resolution of my monitor is 1920x1280 and that of the SG3 is 1280x720. I am hoping that I can force the system to use the resolution 1920x1280 so that the automatic conversion you are talking about will not happen. My next problem is that I don't know what will happen if I try to drive the phone display at that resolution. Will the phone cease to work or will the phone display just look bad. The latter case would work for me as I would use a USB hub with keyboard and mouse as input devices when the MHL connector were attached. But I *am* a little bit concerned that I have not seen any post on the web saying something like "I am running Ubuntu on my SG3 with a external HDMI monitor and everything works like a peach".

I am not too familiar with Samsung's implementation of Android (touchwiz) so there can definitely be something happening in the background auto switching audio output to TV only. But you are right it sounds more like software than hardware. I searched the web quickly and found others with a similar problem and having to use a app to get around it. the app is called SoundAbout (free) and a paid for pro version (seemingly required for Bluetooth functionality). Hopefully that will help.


As for the resolution issue the first thing is that your phone screen resolution can not be changed. It definitely can never get higher than its native resolution, like a PC monitor, but unlike a PC monitor it can not be lowered either. So the phone side is fixed. Now for the PC monitor, you can't scale 1280x720 to 1920x1200 without some kind of stretching. the first has an aspect ratio of 16:9 and the latter has an aspect ratio of 16:10. 1280x720 would go nicely into 1920x1080 for reference. Once you plug the phone into the monitor, use the monitor settings to adjust how it scales the content (on my dell its called wide mode, under display settings). Also note that its not going to work well at all if you have it in portrait orientation because then your resolution is effectively swapped so it would be 720x1280, you'll have wide vertical bars on either side and you will lose 80 lines of data on your desktop.

As an aside, you mention using MHL for video out and also using a USB hub for a keyboard and mouse. Unless I am misunderstanding your intent, this is not possible. you can use the MHL output for either traditional USB tasks, or HDMI out but not both simultaneously.

Edit: above I was assuming phones that can only clone their displays to an external source. There are some new phones that actually allow you to use an external monitor as a second display. In this case you should be able to use your external monitors native resolution. These newer phones will automatically output that resolution. right now that is the exception not the rule though.

[Bo Martins]

I am not too familiar with Samsung's implementation of Android (touchwiz) so there can definitely be something happening in the background auto switching audio output to TV only. But you are right it sounds more like software than hardware. I searched the web quickly and found others with a similar problem and having to use a app to get around it. the app is called SoundAbout (free) and a paid for pro version (seemingly required for Bluetooth functionality). Hopefully that will help.


As for the resolution issue the first thing is that your phone screen resolution can not be changed. It definitely can never get higher than its native resolution, like a PC monitor, but unlike a PC monitor it can not be lowered either. So the phone side is fixed. Now for the PC monitor, you can't scale 1280x720 to 1920x1200 without some kind of stretching. the first has an aspect ratio of 16:9 and the latter has an aspect ratio of 16:10. 1280x720 would go nicely into 1920x1080 for reference. Once you plug the phone into the monitor, use the monitor settings to adjust how it scales the content (on my dell its called wide mode, under display settings). Also note that its not going to work well at all if you have it in portrait orientation because then your resolution is effectively swapped so it would be 720x1280, you'll have wide vertical bars on either side and you will lose 80 lines of data on your desktop.

As an aside, you mention using MHL for video out and also using a USB hub for a keyboard and mouse. Unless I am misunderstanding your intent, this is not possible. you can use the MHL output for either traditional USB tasks, or HDMI out but not both simultaneously.

Edit: above I was assuming phones that can only clone their displays to an external source. There are some new phones that actually allow you to use an external monitor as a second display. In this case you should be able to use your external monitors native resolution. These newer phones will automatically output that resolution. right now that is the exception not the rule though.

Hi Auzo and Suntan

My audio problem is history. Thank you. Thank you. The app did the trick. And yes the professional license was needed in order to activate the bluetooth functionality.

About the video, I consider any kind of upscaling a no-go. The whole idea is to use the phone not only as a phone but also as a desktop computer with a big nice display 23" at least (in emergency cases you could use it as a laptop as well but you would then have to carry the monitor and keyboard and mouse). Looking at an upscaled image defies the whole purpose. The external monitor thing sound exactly right. If that does not fly, I am sunk.

About the combination with MHL adapter and USB hub, I was considering the following configuration: SG3+MHL adapter+active USB hub+USB keyboard+USB mouse+USB bluetooth dongle. That way I would not need batteries for the keyboard and mouse.

Thank you both of you for your interest in these problems and best regards, Bo

[Suntan]

Hi Auzo and Suntan

My audio problem is history. Thank you. Thank you. The app did the trick. And yes the professional license was needed in order to activate the bluetooth functionality.

About the video, I consider any kind of upscaling a no-go. The whole idea is to use the phone not only as a phone but also as a desktop computer with a big nice display 23" at least (in emergency cases you could use it as a laptop as well but you would then have to carry the monitor and keyboard and mouse). Looking at an upscaled image defies the whole purpose. The external monitor thing sound exactly right. If that does not fly, I am sunk.

About the combination with MHL adapter and USB hub, I was considering the following configuration: SG3+MHL adapter+active USB hub+USB keyboard+USB mouse+USB bluetooth dongle. That way I would not need batteries for the keyboard and mouse.

Thank you both of you for your interest in these problems and best regards, Bo

I tried the whole USB hub thing. It doesn't work (contrary to supposition in the blogs around the time the new adapter was released.) If you plug in the MHL, you lose the USB OTG functionality. Not having dedicated mHDMI and USB ports on the phone is probably my biggest issue with the device, and the one thing I miss from my old Droid 3.

-Suntan

[Bo Martins]

I tried the whole USB hub thing. It doesn't work (contrary to supposition in the blogs around the time the new adapter was released.) If you plug in the MHL, you lose the USB OTG functionality. Not having dedicated mHDMI and USB ports on the phone is probably my biggest issue with the device, and the one thing I miss from my old Droid 3.

-Suntan

Suntan, take a look at 18:38 in the video that started this thread ( ). It demonstrates that the MHL adapter does indeed work together with both keyboard and mouse. They are connected using bluetooth, i.e not USB OTG.

Best regards,

Bo

[Suntan]

Yeah, I know. You can still access bluetooth, but you can't access USB OTG when using the MHL. That was the point.

Envision the MHL powered by a powered USB hub with a USB flash or disc drive attached for added storage, in addition to a USB keyboard and/or mouse.

Or to be able to connect a USB keyboard/mouse/gamepad in and be able to run the audio through BT headphones while working/playing on the large screen.

-Suntan

[Rylee Curran]

my galaxy s3 MHL adapter when plugged into the HDMI TV input it shuts down my 3g internet and my phone signal. if anyone knows why my adapter would force or invoke is the internet and phone signal drop please reply. I do know that I have signal coverage in location of me testing but shuts down as soon as it switches to MHL HDMI output.

[NZtechfreak]

my galaxy s3 MHL adapter when plugged into the HDMI TV input it shuts down my 3g internet and my phone signal. if anyone knows why my adapter would force or invoke is the internet and phone signal drop please reply. I do know that I have signal coverage in location of me testing but shuts down as soon as it switches to MHL HDMI output.

That sounds very unusual, certainly should not be the case at all. Are you on custom ROM/kernel?

[Rylee Curran]

Negitive. I just need a easy way to hook Netflix up to my non-internet compatible hd t.v. I have sent two adapters back believing that to be the issue but it persists with the new adapters too. LG t.v to hopefully netflix on my phone. I would try it with another hdmi but I only have the one t.v. so the best I can hope for is maybe radio shack will let me test on their floor models but haven't had the time.