See the full Linux orbbec.ini file contents pasted below!
On Windows (which has a less documented .ini file) changing the [Depth]
and [IR]
resolution to 17
worked as well 
;---------------- Sensor Default Configuration -------------------
[Device]
; Mirroring. 0 - Off (default), 1 - On
;Mirror=1
; FrameSync. 0 - Off (default), 1 - On
;FrameSync=1
; Stream Data Timestamps. 0 - milliseconds, 1 - microseconds (default)
;HighResTimestamps=1
; Stream Data Timestamps Source. 0 - Firmware (default), 1 - Host
;HostTimestamps=0
; A filter for the firmware log. Default is determined by firmware.
;FirmwareLogFilter=0
; Automatic firmare log retrieval. 0 - Off (default), or the number of milliseconds between log retrievals operations.
;FirmwareLogInterval=1000
; Print firmware log to console when automatic firmware log retrieval is on. 0 - Off (default), 1 - On
;FirmwareLogPrint=1
; Is APC enabled. 0 - Off, 1 - On (default)
;APCEnabled=1
; USB interface to be used. 0 - FW Default, 1 - ISO endpoints (default on Windows), 2 - BULK endpoints (default on Linux/Mac/Android machines), 3 - ISO endpoints for low-bandwidth depth
UsbInterface=2
[Depth]
; Output format. 100 - 1mm depth values (default), 102 - u9.2 Shift values.
;OutputFormat=100
; Is stream mirrored. 0 - Off, 1 - On
;Mirror=1
; 0 - QVGA, 1 - VGA, 4 - QQVGA. Default: Arm - 4, other platforms - 0, -14 1280x720, 15 1280x960,-16 1280x800, -17 640x400 -20 320x200,-26 800x1280,-27 400x640
Resolution=17
; Frames per second (default is 30)
;FPS=30
; Min depth cutoff. 0-10000 mm (default is 0)
;MinDepthValue=0
; Max depth cutoff. 0-10000 mm (default is 10000)
;MaxDepthValue=10000
; Input format. 0 - Uncompressed 16-bit, 1 - PS Compression, 3 - Packed 11-bit, 4 - Packed 12-bit. Default: Arm - 4, other platforms - 3
InputFormat=3
; Registration. 0 - Off (default), 1 - On
;Registration=1
; Registration Type. 0 - Don't care (default), 1 - use hardware accelaration, 2 - perform in software
;RegistrationType=0
; software filter 0-off ,1--on (default)
;SoftFilter=0
;ReadParams=0
; dual sensor: 5.96 mm
;focallength=5.96
;dual sensor: 0.0052mm
;dPlanePixelSize=0.113967
;dPlaneDistance=130
;dual sensor: 75mm
;dEmitterDcmosDistance=7.500000
;dhorizontalFov=0.022600
;dverticalFov=0.796616
; Hole Filler. 0 - Off, 1 - On (default)
;HoleFilter=0
; White Balance. 0 - Off, 1 - On (default)
;WhiteBalancedEnabled=0
; Gain. 0-50 (0 - Auto, 1 - Min., 50 - Max.). Default value is set by firmware.
;Gain=0
; Close Range Mode. 0 - Off (default), 1 - On
;CloseRange=1
; GMC Mode. 0 - Off, 1 - On (default)
;GMCMode=0
; GMC Debug. 0 - Off (default), 1 - On
;GMCDebug=1
; Depth Auto Gain Region-of-Interest. Default values are set by firmware.
;DepthAGCBin0MinDepth=500
;DepthAGCBin0MaxDepth=800
;DepthAGCBin1MinDepth=1500
;DepthAGCBin1MaxDepth=1800
;DepthAGCBin2MinDepth=2500
;DepthAGCBin2MaxDepth=2800
;DepthAGCBin3MinDepth=3500
;DepthAGCBin3MaxDepth=3800
; Wavelength Correction Mechanism. 0 - Off (default), 1 - On
;WavelengthCorrection=1
; Wavelength Correction debug info. 0 - Off (default), 1 - On
;WavelengthCorrectionDebug=1
; Cropping mode. 1 - Normal (default), 2 - Increased FPS, 3 - Software only
;CroppingMode=2
; Cropping area
[Depth.Cropping]
OffsetX=0
OffsetY=0
SizeX=320
SizeY=240
;Enabled=1
[Image]
; Output format. 200 - RGB888 (default), 201 - YUV422, 202 - Gray8 (2.0 MP only), 205 - YUYV
;OutputFormat=201
; Is stream mirrored. 0 - Off, 1 - On
;Mirror=1
; 0 - QVGA (default), 1 - VGA, 2 - SXGA (1.3MP), 3 - UXGA (2.0MP), 14 - 720p, 15 - 1280x960
Resolution=1
; Frames per second (default is 30)
;FPS=30
; Input format. 0 - Compressed 8-bit BAYER (1.3MP or 2.0MP only), 1 - Compressed YUV422 (default in BULK), 2 - Jpeg, 5 - Uncompressed YUV422 (default in ISO), 6 - Uncompressed 8-bit BAYER (1.3MP or 2.0MP only), 7 - Uncompressed YUYV
InputFormat=5
; Anti Flicker. 0 - Off (default), 50 - 50Hz, 60 - 60 Hz.
;Flicker=50
; Image quality when using Jpeg. 1-10 (1 - Lowest, 10 - Highest (default))
;Quality=10
; Cropping mode. 1 - Normal (default), 2 - Increased FPS, 3 - Software only
;CroppingMode=1
; Cropping area
[Image.Cropping]
;OffsetX=0
;OffsetY=0
;SizeX=320
;SizeY=240
;Enabled=1
[IR]
; Output format. 200 - RGB888, 203 - Grayscale 16-bit (default)
;OutputFormat=203
; Is stream mirrored. 0 - Off, 1 - On
;Mirror=1
; 0 - QVGA (default), 1 - VGA, 2 - SXGA(1.3MP), 4 - QQVGA. -14 1280x720, 15 1280x960,-16 1280x800, -17 640x400 -20 320x200,-26 800x1280,-27 400x640
Resolution=17
; Frames per second (default is 30)
;FPS=30
; Cropping mode. 1 - Normal (default), 2 - Increased FPS, 3 - Software only
;CroppingMode=1
; Cropping area
[IR.Cropping]
;OffsetX=0
;OffsetY=0
;SizeX=320
;SizeY=240
;Enabled=1