hey

hello, Jonatan!

how can I help you today?

I'm having trouble with integrating camera API

aren't we all :-)

:p

we have an an app that's loading a preview window at the right scale but then when the picture is snapped the scale and cropping is off

"the scale and cropping is off" on the preview or on the picture?

on the picture

that's the code we use for the preview, that I'm trying to apply to the picture

well, the preview resolution is unlikely to bear much resemblance to the picture resolution

so, you can't just directly apply the calculations you used for the preview resolution to the picture

right so the actual picture pixels are different so you're saying I need to re-calculate something that ends up similar instead of trying to apply the same logic

right

ok, thanks, that makes sense :)

plus, you'd have to experiment to try to determine how best to approach that

suppose the picture is 4K (3840 x 216)

er, 3840 x 2160

and suppose the preview is 1080p (1920 x 1080)

in that case, the picture is double the size, along both axes

however, that does not necessarily imply that the center of the picture is the center of the preview

I would hope that it would be

but I have had so many assumptions trashed by device manufacturers and their cameras, that I try not to make any more than are necessary

right

things get more complicated if the aspect ratios differ

I would probably start off hoping that the picture center and the preview center are the same

but then test the heck out of it

that's why I have The Wall of Phones here in my Secret Mountain Lair

for testing my camera library

haha

I was hoping I would be able to hook into some cloud lab

in the future

IIRC, Amazon's lab is set up that cameras at least kinda sorta work

I was looking at I was looking at https://github.com/commonsguy/cwac-cam2 is there any code there I could use as a reference for what I'm trying to do?

not for this particular problem

I have specifically sworn off trying to worry about synchronizing the preview to the picture

IMHO, the preview is simply for aiming

the picture is what the picture is

and the user can do their own cropping or other post-processing on their own

right, except in ios it looks exactly the same so the android versions should too :)

it's a selfie snapchat-like app

if you have other questions, go right ahead -- it's a quiet chat room today

still on the camera just trying to figure this out: Could I apply a matrix transformation somehow on the actual picture like I'm doing for the preview?

um, perhaps as part of rendering the image to a Bitmap-backed Canvas or something

I found and am trying CaptureRequest.SCALER_CROP_REGION but this only takes a Rect object

(on the Capturebuilder)

to be honest, I rarely use Matrix, and I have never tried SCALER_CROP_REGION (as I'm still aiming to support pre-5.0 devices)

right

I think our pre-5.0 is working better actually

for a more simple camera app would it be a problem to just go with the old camera api?

that depends on the scope of "a problem"

tactically, it should be fine, as all devices still need to support it, for backwards compatbility

however, getting device manufacturers to adhere to APIs with respect to cameras is difficult as is

particularly since Google doesn't test it much in the CTS, per yesterday's fireside chat

my expectation is that device manufacturers will focus on the 2nd generation API, for what little compatibility testing they do

which means that over time, support for the 1st generation API will decay

so, given a choice between "use the 1st generation API exclusively" or "don't ship", use the 1st generation API exclusively for now

however, getting reliable support for the 2nd generation API is reasonably important, increasingly so as time passes

right

make it work for now with old API and then make sure the new one is working asap

so long as "asap" doesn't degrade to "the Tuesday after never"

you know how engineering priorities can shift

what, that never happens right :)

oh, well, I'm only speaking theoretically

great, thanks

and *certainly* not from personal first-hand experience

:-)

haha

Thanks for the help Mark, I'm going to log out and see if I can make these camera troubles go away.

OK, best o' luck!

Thanks, bye