Android Question [SOLVED]Capture image from Camera2 with overlaid compass

[josejad]

Hi everybody:

I use Camera2 to make pictures in my app. In some of these pictures, I need to know the compass orientation, so I've overlaid a compass over the camera preview, and I need to save the image with the overlaid compass.
I've tried to define

pnlCamera as B4XView
..
cam.Initialize(pnlCamera)
...
Dim bmp As B4XBitmap = pnlCamera.Snapshot

But I get a black screen with the compass and the views in the pnlCamera, but not the image itself.
The resulting image is too small too (about 19kb).

I've been reading about BitmapCreator, but not sure if it's what I need. Maybe with this I could save the image as always, the pnlCamera.Snapshot and overlay them?

Thanks.

 

[Erel]

You can use BitmapCreator or Canvas / B4XCanvas.

With BitmapCreator it will be something like:

Dim bmp As B4XBitmap = cam.DataToBitmap(Data)
Dim bmp2 As B4XBitmap = LoadBitmap(File.DirAssets, "android-chrome-192x192.png")
Dim bc As BitmapCreator
bc.Initialize(bmp.Width, bmp.Height)
bc.CopyPixelsFromBitmap(bmp)
Dim r As B4XRect
r.Initialize(20dip, 20dip, 0, 0)
r.Width = bmp2.Width
r.Height = bmp2.Height
bc.DrawBitmap(bmp2, r, False)
Dim mergedbmp As B4XBitmap = bc.Bitmap

 

[josejad]

Awesome¡¡ It works¡¡
Is there a way of setting the color panel to transparent. I've set to transparent, but I get it black

Thanks

 

[josejad]

I've been reading about DrawBitmapCreator, searching about transparency...
In the thumbnail it seems to work, but in the image I don't get the compass with transparent background.
I've changed the line

bc.DrawBitmap(bmp2, r, False)

with

bc.DrawBitmapCreator(bc,r,50,50,True)

but no success...

        Dim bmp As B4XBitmap = cam.DataToBitmap(Data)
        Dim bmp2 As B4XBitmap = pnlCompass.Snapshot
        Dim bc As BitmapCreator
        bc.Initialize(bmp.Width, bmp.Height)
        bc.CopyPixelsFromBitmap(bmp)
        Dim r As B4XRect
        r.Initialize(20dip, 20dip, 0, 0)
        r.Width = bmp2.Width
        r.Height = bmp2.Height
        bc.DrawBitmapCreator(bc,r,50,50,True)
        Dim mergedbmp As B4XBitmap = bc.Bitmap

 

[Erel]

The code I posted keeps the transparent parts. The problem is in the bitmap that you are drawing.

Why are you using pnlCompass.Snapshot? How are you creating this compass?

 

[josejad]

I have a transparent panel with the compass over the camera image preview, with Johan Schoeman NewCompassView.

https://www.b4x.com/android/forum/threads/compassview-another-compassview.93977/#content

So I get a snapshot of the panel when I take the picture to get it overlaid over my captured photo

 

[josejad]

The code I posted keeps the transparent parts. The problem is in the bitmap that you are drawing

You're right. Just adding:

pnlCompass.Color = Colors.Transparent

I get it right¡¡
I thought just setting the transparency level to 0 in designer was enough, but it's not

Thanks a lot