Images appear grainy via miracast - Xperia Z Q&A, Help & Troubleshooting

So I got a new Philips TV yesterday, which supports miracast. I was playing around with it yesterday, and found that images are very very grainy when I use the throw functionality. Is there a setting to change for it to send through full image res? As videos appear as normal, the issue is with images only.

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HDMI 1080p?

So, as far as i can tell, on an HD dock, the device is outputting a native 1080p signal.
But the highest *resolvable* res is the native 540p of the device.
Is there any way to hack the framebuffer to be 1080p (possibly using a tablet version of ADW or other such launchers?), strictly during HDMI mirroring?
End goal: running 1080p ubuntu while docked + HD netflix and HD photo viewing.
My TV reports a 1920x1080 input resolution but for anything mirrored, it is just 960x540 being upconverted by the phone. Apps like picture and camera video players and youtube appear to be higher res since they can display the media only on the HDMI connected screen and on the phone black space will show.
If someone can figure out a way to get the phone to disable mirroring the displays and instead only use the HDMI connected display then you may be able to get it to output something in native 1080p without upconversion.
I don't know if this answers your question but i find turning my phone sideways puts the phone in full screen. youtube sucks though it looks like its all pixely

[Q] Changing Camera Available Resolutions

Hello Guys,
After searching all around I have not been able to find a solution for my problem. I am streaming video to youtube live, the problem is the phone shows 640x368 as the available resolution and youtube asks for 640x360 which is the standard resolution, and therefore rejects my stream.
I have tried 2 different software for streaming, but both of them only show the available resolutions, they can not modify the picture at all.
Is there any way I could change the available camera resolutions withing the ROM?
I am using Android Revolution HD 51.0

Will Google Cast ever do 1080p?

I am using Chromcast to display a static website on a large display at work via Casting a Tab with Google Cast. The text looks fuzzy on 720p modes. Do you think Google will ever put in a 1080p mode into Google Cast?
I'm guessing not unless they do a major revamp of how it works. In your case your best result will either be to cast a 720p-sized tab (use the option to resize the tab for best display) or use Vbukit to display the site.
You'll get poor results - both performance-wise and quality-wise - if it has to downscale a larger image to 720p then have the display upscale that downscaled result. Displaying a native 720p image upscaled to 1080p should look pretty good. Fact of the matter is, some of the HD TV content you receive is still 720p so it's being upscaled too.
bhiga said:
I'm guessing not unless they do a major revamp of how it works. In your case your best result will either be to cast a 720p-sized tab (use the option to resize the tab for best display) or use Vbukit to display the site.
You'll get poor results - both performance-wise and quality-wise - if it has to downscale a larger image to 720p then have the display upscale that downscaled result. Displaying a native 720p image upscaled to 1080p should look pretty good. Fact of the matter is, some of the HD TV content you receive is still 720p so it's being upscaled too.
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Thank you for the reply.
I bit the bullet and ordered up a 25ft HDMI cable and will have it run from the display to the workstation what is "serving" up this website.
I really need the 1080p resolution to be able to fit all the content and have it readable.
dmwagner said:
I really need the 1080p resolution to be able to fit all the content and have it readable.
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Got it. I suggested Vbukit but it seems the 2.0 version has removed the ability to send web URLs - seems they were just snapshots anyway though.
Actually, if you find you really need to be un-wired and it's a static or scripted website demonstration, you could make a photo stream or video and present that.
Vbukit can present PowerPoint among other Office filetypes.

What is resolution of CC mirroring?

Since I got CC mirroring feature on my Nexus 7 2013 LTE running stock 4.4.3 the quality seems very good.
Compared to another Miracast device, I suspect the CC mirroring is *better* resolution.
Does anyone know the actual CC resolution specs of the signal to be displayed?
Or, is there some test I can do with my monitor and figure out for myself?
I've actually been wondering this myself...
Chromecast itself outputs 480p, 720p and 1080p (not sure about 1080i) - that's what the TV receives, because it's an HDMI video device, as opposed to a computer HDMI output.
So whatever resolution file or stream is being displayed needs to get up- or down-scaled to one of the supported resolutions.
The core question, what resolution is the image, before scaling, that is to be sent to Chromecast?
To test this, we need a video file that will show scaling. A frame full of alternative black and white horizontal lines is usually enough. So, to test if it's putting out 1080p, you make a 1920x1080 file with alternating black and white horizontal lines (540 white, 540 black) then display it on Chromecast to a 1080p TV.
Replace 1080p with 720p if you only have a 720p TV. If you have a TV that is not native 480p, 720p or 1080p you can't really do this test unless the TV supports a 1:1 mode that bypasses scaling.
If the image displays as a solid single shade of gray (or if you have sharp eyes, alternating single pixel black and white lines) then there's no scaling and Chromecast is receiving a 1080p resolution signal.
If you see "bands" of gray or fat lines, there is scaling going on, and Chromecast is not receiving a 1080p signal.
I'll try to do a test...
Managed to do a quick test... Basic screen mirroring seems to happen at screen resolution (makes sense).
One thing I'd like to test but couldn't is playback of a video file using the native Video Player app (which displays a screen cast icon during casted playback). I suspect it just sends the video data directly to Chromecast in this (special) case.
Most of the models that support Mirroring already use at least 720 resolution for their screens so it may not need to do any upconverting at all.
Asphyx said:
Most of the models that support Mirroring already use at least 720 resolution for their screens so it may not need to do any upconverting at all.
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All depends... I don't think (or at least haven't noticed) Chromecast changes resolution once it "decides" so even if the device is sending 720p, if Chromecast it at 1080p, something somewhere needs to upscale.
Okay, did a follow-up test with a Handbrake-converted (native Video Player can't handle TS) version of the Alternating black/white 1 pixel full field 1920x1080 from www.w6rz.net.
I also used Overscan lines at 0, 2.5 and 5.0 percent with 0 to 16 pixel cropping bars 1920x1080 to verify what was happening in different modes since the native Video Player doesn't explain (damn icon-based reality, this is why I don't like toolbars!).
On the TV...
Avia:
Shows proper single-pixel lines on Chromecast
This serves as the control image for full 1080p as Avia just sends the native video over without scaling.
MX Player:
100% shows proper single-pixel lines on Chromecast, and on my phone single-pixel lines using SW decoder, and banded gray on my phone using HW and HW+ decoder (which is odd - points to an anomaly/defect in the decoder, perhaps)
Fit to Screen shows even, fat lines
Stretch shows banded fat lines
Crop shows banded fat lines
Video Player:
Two corners (Fit?) shows even, fat lines (same image as Fit to Screen in MX Player)
Letterbox shows even, fat lines (same image as Fit to Screen in MX Player)
Four corners (Stretch?) and Full (Crop?) show banded fat lines
If the native Video Player did, as I had hoped, output the full native resolution to Chromecast, I should have seen proper single-pixel lines, looking gray from a distance, but alternating black/white up close.
Sadly, Video Player does not seem to do this, sending the device's native resolution, or some derivative. This makes me wonder why Video Player blanks out the screen during screen casting - casting other content works fine with video going to the screen and Chromecast. It might be to ensure the best framerate or something, but seems odd to me.
I don't know what magic they implemented, but my HTC One can be mirrored without any noticeable loss of picture quality. Compare that to the casting of the screen of a powerful i7 PC that lags heavily every time I used it (little bit better with Canary).
Either some frames are dropped to keep up, or the bitrates are lower but whatever they did I like it.
jasenko said:
I don't know what magic they implemented, but my HTC One can be mirrored without any noticeable loss of picture quality. Compare that to the casting of the screen of a powerful i7 PC that lags heavily every time I used it (little bit better with Canary).
Either some frames are dropped to keep up, or the bitrates are lower but whatever they did I like it.
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Especially head-to-head against Miracast (Samsung AllShare Cast Wireless hub), I prefer the Chromecast implementation - no noticeable picture break-up and framerate feels more consistent.
Some of the articles say Google wrote their own framework for it. Given that it also seems to work quite nicely on my Galaxy S3 which is a lot less horsepower than the Galaxy S4, I'm very impressed. Even for streaming Internet video (Xfinity TV Go) it's working very well. My only problem is my phone overheats on long streaming sessions (over an hour) and the battery stops charging, heh. Not bad considering the S3 isn't officially supported to begin with.
@bhiga
I would think the scaling happens in the loaded APP and not the CCast itself which would explain what you are seeing...
The TV doesn't really change it's res based on what the CCast is being sent the App loaded does the upscaling and thats why it looks as bad as it does,
Kind of like taking a 640X320 video and displaying if full screen on an HD TV!
So it's not a hardware thing just a software thing and doubles pixels as needed.
Asphyx said:
@bhiga
I would think the scaling happens in the loaded APP and not the CCast itself which would explain what you are seeing...
The TV doesn't really change it's res based on what the CCast is being sent the App loaded does the upscaling and thats why it looks as bad as it does,
Kind of like taking a 640X320 video and displaying if full screen on an HD TV!
So it's not a hardware thing just a software thing and doubles pixels as needed.
Click to expand...
Click to collapse
Yes, the Chromecast->TV resolution stays fixed AFAIK.
I'm not sure whether Chromecast reports its negotiated resolution back to the the framework or app using it, which is why I think it just happens in the Chromecast hardware - after all, you can send Chromecast random-sized "raw" video in a supported compression and it'll still scale up/down as necessary. Doesn't really matter where/how it happens, though.
The question here was whether Chromecast screen casting took the image at the device's screen resolution, or if it somehow created a "virtual" screen at whatever resolution Chromecast is sending to the TV and rendered directly to that as well.
I didn't expect it to do so for non-video stuff, and it doesn't. It's essentially just sending the screen buffer to Chromecast as well as to the device's screen.
The native Samsung Video Player*, however, does not show the video on the device while screen casting (so it's not sending the screen's buffer) - it only shows it on Chromecast, which made me hope that perhaps it was sending the full-resolution video, rather than the scaled version for the device's screen. Unfortunately that does not seem to be the case.
So the core story seems to be
Screen cast quality is dependent on the device' screen resolution.
Higher screen resolution = higher quality screen casted image, up to 1080p.
Lower screen resolution = lower quality screen casted image. If your device's screen resolution is less than the resolution Chromecast is outputting to your TV (1080p or 720p), your screen casted Chromecast output will be degraded.
The native Samsung Video Player does not show the video on the device screen while screen casting, but that does not seem to change the image resolution. In other words, on a device with a 720p screen, playing a 1080p video while screen casting yields a 1080p original -> 720p scaled down for screen -> 1080p scaled up for TV, rather than 1080p original -> 1080p for TV
* Note that this is based on AT&T Samsung Galaxy S3, so the "native Video Player" is the Samsung Video app from TouchWiz. Behavior may be different in other ROMs that use a different video player. I just found it curious that the native Samsung Video did not show the video image during playback. Other video apps like MX Player screen cast fine while showing the video on both Chromecast and the device's screen.
VLC shows video controls while casting the video, very convenient.
Great discussion and research. Thanks.
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I ran a test with Adobe Reader and FBReader to view a .pdf file via CC mirroring on my HDMI monitor. I reduced the font size until they were unreadable on the Nexus 7 (2013) LTE, but they were still very clear on the HDMI monitor. Generally, I still did not find a solution to read side-by-side pdf documents on my HDMI monitor. LOL
During this test I noticed text display done with a *2* pass screen draw on the HDMI monitor. Makes me think Google CC mirroring implemented some sort of 2 pass resolution: e.g. pseudo algorithm might go:
Pass 1) draw reduced resolution, if static image go to pass 2 else dynamic image (movie) loop to next frame.
Pass 2) draw fill to enhance resolution of static image.
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Another test might be comparing same image displayed two ways.
(1) First screen cast via CC compared to
(2) second using an application that's capable of *true* CC
(where *true* - CC fetches its own image and displays full resolution. I'm also assuming full resolution is 1080?)

Camera & Live Photo

The LG V40 ThinQ has a Live Photo mode similar to later iPhones. That photo is about 9 frames of video with sound and 1 picture. There are a few things I can't figure out though.
A. Is the photo 9 frames at full resolution, with audio tacked on.
or is it 1 frame + a small connected movie
B. Can I edit this off-phone, can I peel out all the frames and pick the best one, or edit/use the video portion elsewhere.
There are a few things I have done so far, that are not satisfying my needs.
save to video, or screen cap in the phone, both provide terrible results.
using the "in-phone" saved video outside the phone, also terrible.
Any help would be appreciated
Did you manage to solve the live photo problem? I am looking for a solution for finding and making copies of photos that were made in live photo (visible in the gallery when browsing but not saved an mp4). I sent this question to LG technical support but so far I have no answer.

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