NXP Semiconductors ASUG, Руководство пользователя

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Table 16. Camera sensor parameters
Parameter Discription
mFocalLength Sensor focal length
mPhysicalWidth Sensitive element width
mPhysicalHeight Sensitive element height
8.4 How to configure the logical display density
The Android UI framework defines a set of standard logical densities to help application developers target application resources.
Device implementations must report one of the following logical Android framework densities:
• 120 dpi, known as 'ldpi'
• 160 dpi, known as 'mdpi'
• 213 dpi, known as 'tvdpi'
• 240 dpi, known as 'hdpi'
• 320 dpi, known as 'xhdpi'
• 480 dpi, known as 'xxhdpi'
Device implementations should define the standard Android framework density that is numerically closest to the physical density
of the screen, unless that logical density pushes the reported screen size below the minimum supported.
To configure the logical display density for framework, you must define the following line in
init.rc under ${MY_ANDROID}/
device/fsl/
:
setprop ro.sf.lcd_density <density>
• For the i.MX 8M Mini board, the source folder is ${MY_ANDROID}/device/fsl/imx8m/evk_8mm/init.rc.
• For i.MX 8M Nano Board, the source folder is ${MY_ANDROID}/device/fsl/imx8m/evk_8mn/init.rc.
• For i.MX 8MQuad AIY Board, the source folder is ${MY_ANDROID}/device/fsl/imx8m/aiy_8mq/init.rc.
• For the i.MX 8QuadXPlus MEK board, the source folder is ${MY_ANDROID}/device/fsl/imx8q/mek_8q/init.rc.
NOTE
8.5 How to enable low-power audio
The "DirectAudioPlayer" application is provided to support audio playback from DirectOutputThread. The source code is in
$
{MY_ANDROID}/vendor/nxp-opensource/fsl_imx_demo/DirectAudioPlayer
. After the "vendor.audio.lpa.enable" property is
set to 1, low-power audio can be enabled. In this situation, audio can keey playing even if the system enters suspending mode.
By default, the music stream plays from MixedThread. To make stream play from DirectOutputThread, add the
AUDIO_OUTPUT_FLAG_DIRECT flag to the related tracks. On the Android Application layer, there is no
AUDIO_OUTPUT_FLAG_DIRECT flag to specify DirectOutputThread explicitly. Instead, use FLAG_HW_AV_SYNC when there
is "new AudioTrack" in the application. Then the Android audio framework will add AUDIO_OUTPUT_FLAG_DIRECT for this
track, and this stream will play from DirectOutputThread.
In low-power audio mode, the default audio period time is 1 second, and the whole buffer can hold 60 seconds data. These two
parameters can be configured by the
vendor.audio.lpa.period_ms
and
vendor.audio.lpa.hold_second
properties as
follows:
> setprop vendor.audio.lpa.hold_second 60
> setprop vendor.audio.lpa.period_ms 1000
NXP Semiconductors
Customized Configuration
Android
™
User's Guide, Rev. P9.0.0_2.3.2, 6 March 2020
User's Guide 23 / 31