Fix 1x3 mode Liveview Using An Android phone

[SubZeroz]

Hi,

Shooting with the 1x3 mode is a bit hard, as the live view is small and squeezed.


After I've seen Zeek's video and found out theres an option to use my phone as a screen, I came up with an idea.

I've decided to make an Android app that would stretch the image, so we can use a bigger screen & see the way it really is.


Camera Screen:



Phone with my app (6.1 inch Android 9):


The camera output (MLV FILE):

Pay attention. About 20% of the lower part of the final image is being cut out. I think this is because the original preview does not contain that data.




____________________________________________

Using the app:

1. Enter the App

2. Choose HDMI input res:

https://i.imgur.com/CAtPdf4.png

Use 1920x1080 unless you have a good reason not to


3. Choose current preset mode:
https://i.imgur.com/eBjH3yz.png

(I've tested only 2.35:1 and 16:9)

4. You'll get a blank black screen

5. Connect everything, while your camera is OFF (Otherwise there might be some artifacts. This can be fixed by turning the camera off and on)

6. Make sure you're on the first LiveView option (Do not press INFO, it might cause corrupted frames in the final video)




App Download Link:
https://drive.google.com/file/d/1dOcNt850aPptU8q-PGLrSgyJEqvO83YX

Github Project:
https://github.com/johnnyron/SimpleAndroidUsbCamera



The problem with stretching is that it depends on your screen ratio. For example if you dont have a wide phone, you would have to either
1. Use a smaller height with the same width, so it will fill the entire screen, but you'll see a much smaller image
2. Stretch it so you'll see only a portion of the image, but at the correct aspect ratio.

My phone worked O.K with 2.35:1, so I've only stretched it to the entire screen. If you have a different phone screen ratio you can make changes to the code to make it match ur screen.

I've currently tested only HDMI-INPUT 1920x1080 & aspect ratio of 2.35:1 and 16:9. If you test anything else and have any issues please write here.

Note:
This project is based on https://github.com/jiangdongguo/AndroidUSBCamera
(I didn't even change App's Icon) and has code that I didn't write. Use this app at your own risk :-)

[theBilalFakhouri]

Hello @SubZeroz

Which 1x3 preset and build are you using?

[theBilalFakhouri]

From 700D thread it seems you are using crop_rec_4k_mlv_snd_isogain_1x3_presets_2019Apr02.700D115.zip build, this build doesn't contain Real-Time Correct Preview presets for 1x3 Binning mode, even if you used this method to correct the preview it won't be accurate or perfectly correct, instead for now you can use my build in 700D thread which contain correct preview presets for 1x3 Binning, or maybe Danne would add the correct preview presets to this build in future.

[SubZeroz]

Hi Bilal,

700d,
Currently on https://bitbucket.org/Dannephoto/magic-lantern/downloads/crop_rec_4k_mlv_snd_isogain_1x3_presets_2019Apr02.700D115.zip

I was trying your build and it's really cool, but I had some issues:
https://www.magiclantern.fm/forum/index.php?topic=5951.msg231818#msg231818

I Really need the shutter speed to work & Focus peaking in the LiveView.

Also I've tried other Android apps and none use the full-width of my phone.

You can use this app for regular ratio aswell.


Update:
While writing this comment I've seen you've replied in the other thread.
I will post my 700d-related comments in that post.

But first I wish to reply about your latest comment:
"even if you used this method to correct the preview it won't be accurate or perfectly correct"

It is corrected because I stretch the image myself. The only problem is that the original LiveView doesnt contain 20% of the lower part of the image.

But - if anyone is using a different Camera/Build with the LiveView problem, it is much better than having a small squeezed screen.

Don't get me wrong - your version is great and I will probably use it soon & make some adjustments to make it appear on my entire Android screen.

About Focus-Peaking:
If There's really no way to solve this, I might try to do it in the Android App itself. Don't know how hard it'll be yet.

[theBilalFakhouri]

But first I wish to reply about your latest comment:
"even if you used this method to correct the preview it won't be accurate or perfectly correct"

It is corrected because I stretch the image myself. The only problem is that the original LiveView doesnt contain 20% of the lower part of the image.

Yeah, I see you have used the android app to achieve better preview (to correct the preview), but I meant even with using this method, you will still not able to see the full preview, as you mentioned there is 20% cut . .

The new presets solve both the missing part of RAW data in LiveView, and the aspect ratio is correct out of the box without further stretching . .

it is much better than having a small squeezed screen.

700D doesn't have clean HDMI output, there is black bars in the left and in the right directly out of the box, this is not related to the new presets, but to the camera itself, in this case yes your method would give better viewing preview, but I think you might find a way to zoom in the small preview area in the new presets using the Android App, in this way you will get rid of black bars and you will have full preview showing in smartphone screen.

No I am not getting you wrong , use what you prefer

[kpn]

Works great! I've had the same idea but no skill to implement it. Only one problem, the display goes to sleep if you don't tap it once in a while, probably a keep-awake app will help. Otherwise it's perfect, really helps with focus confirmation on 1x3 anamorphic mode on 5D3