Original Author Paul Laughton, 2011
Page 179
De Re BASIC!
Camera application. The difference is the image bitmap is returned to BASIC! for manipulation
by BASIC! The Gr.camera.shoot command implements this mode.
2)
A picture can be taken automatically when the command is executed. This mode allows for
untended, time-sequenced image capture. The command provides for the setting the flash to
on, off and auto. The Gr.camera.autoshoot command implements this mode.
3)
The third mode is the Gr.camera.manualshoot command which is much like the autoshoot
mode. The difference is that a live preview is provided and the image is not captured until the
screen is touched.
All pictures are taken at full camera resolution and stored with 100% jpg quality as "<pref base
drive>/rfo-basic/data/image.png".
All of these commands also return pointers to bitmaps. The bitmaps produced are scaled down by a
factor of 4. You may end up generating several other bitmaps from these returned bitmaps. For
example, you many need to scale the returned bitmap to get it to fit onto your screen. Any bitmaps that
you are not going to draw and render should be deleted using Gr.bitmap.delete to avoid out-of-memory
situations.
The Sample Program, f33_camera.bas, demonstrates all the modes of camera operations. It also
provides examples of scaling the returned image to fit the screen, writing text on the image and deleting
obsolete bitmaps.
The Sample Program, f34_remote_camera.bas, demonstrates remote image capture using two different
Android devices.
Gr.camera.select 1|2
Selects the Back (1) or Front(2) camera in devices with two cameras. The default camera is the back
(opposite the screen) camera.
If only one exists camera exists, then the default will be that camera. For example, if the device (such as
the Nexus 7) only has a Front Camera then it will be the default camera. If the device does not have any
installed camera apps, then there will be a run-time error message, "This device does not have a
camera." In addition, a run-time error message will be shown if the device does not have the type of
camera (front or back) selected.
Gr.camera.shoot <bm_ptr_nvar>
The command calls the device's built in camera user interface to take a picture. The image is returned to
BASIC! as a bitmap pointed to by the bm_ptr numeric variable. If the camera interface does not, for
some reason, take a picture, bm_ptr will be returned with a zero value.
Many of the device camera interfaces will also store the captured images somewhere else in memory
with a date coded filename. These images can be found with the gallery application. BASIC! is not able
to prevent these extraneous files from being created.