Video cameras

Two identical video cameras provide a resolution up to 2560*1920 at 1 frames per second (fps) or 640*480 at 30 fps.

Location

https://developers.softbankrobotics.com/sites/default/files/repository/51_html_nao/_images/cameras_location.png

See the URDF file .

Part Name
A CameraTop
B CameraBottom

Camera indexes

The camera indexes are:

Parameter ID Name ID Value Description
AL::kTopCamera 0 camera on the top.
AL::kBottomCamera 1 camera on the bottom.

Specifications

Camera Model OV5640
Type System-on-a-chip (SoC) CMOS image sensor
Imaging Array Resolution 5Mp
Optical format 1/4 inch
Active Pixels (HxV) 2592x1944
Sensitivity Pixel size 1.4µm*1.4µm
Dynamic range 68db@8x gain
Signal/Noise ratio (max) 36dB (maximum)
Responsivity 600 mV/Lux-sec
Output Camera output 640*480@30fps or 2560*1920@1fps
Data Format YUV and RGB
Shutter type Rolling shutter
View Field of view 67.4°DFOV (56.3°HFOV,43.7°VFOV)
Focus type Auto focus

Parameters

The camera has a list of parameters which can be modified.

Model

Camera Model has the following value:

Parameter ID Name ID Value Description
AL::kOV5640 3 HD Camera

Supported parameters

Software parameters

Parameter Min value Max value Default value Camera ID name ID value
Keep Alive 0 1 0 kCameraKeepAliveID 35

Hardware parameters

Camera ID name ID Value Parameter Min Value Max Value Default Value Remarks
kCameraBrightnessID 0 Brightness -255 255 0
kCameraContrastID 1 Contrast 0 255 32
kCameraSaturationID 2 Saturation 0 255 64
kCameraHueID 3 Hue -180 180 0
kCameraGainID 6 Gain 0 1023 16 Read only if auto exposure enabled
kCameraHFlipID 7 Horizontal Flip 0 1 0
kCameraVFlipID 8 Vertical Flip 0 1 0
kCameraAutoExpositionID 11 Auto Exposition 0 1 1 0: disabled 1: enabled
kCameraAutoWhiteBalanceID 12 Auto White Balance 0 1 1 0: disabled 1: enabled
kCameraExposureID 17 Exposure 0 65535 32 Read only if auto exposure enabled
kCameraSharpnessID 24 Sharpness 0 9 4
kCameraBacklightCompensationID 34 Backlight compensation 0 1 0 0: disabled 1: enabled
kCameraAverageLuminanceID 39 Average Luminance 0 255 NA Read only
kCameraAutoFocusID 40 Auto Focus 0 1 0 0: disabled 1: enabled
kCameraFocusID 43 Manual Focus 0 250 0 This parameter is available only when Auto Focus is disabled Parameter’s step is 25 Use range [0-225] to control the focus Setting the value 250 will trigger a one-shot auto focus

Supported colorspaces

A color space is a model describing the way to represent color as an ordered list of numbers. For example you can represent the color of each pixel of your screen as a list of three elements R, G and B. Which are respectively the value of Red, Green, and Blue usually stored in an byte (range from 0 to 255).

Setting the color space allows you to set the image buffer encoding in AL::ALImage .

Color space parameter for 2D camera can have the following values:

Parameter ID Name ID Value Number of layers Number of channels Description
AL::kYuvColorSpace 0 1 1 Buffer only contains the Y (luma component) equivalent to one unsigned char
AL::kyUvColorSpace 1 1 1 Buffer only contains the U (Chrominance component) equivalent to one unsigned char
AL::kyuVColorSpace 2 1 1 Buffer only contains the V (Chrominance component) equivalent to one unsigned char
AL::kRgbColorSpace 3 1 1 Buffer only contains the R (Red component) equivalent to one unsigned char
AL::krGbColorSpace 4 1 1 Buffer only contains the G (Green component) equivalent to one unsigned char
AL::krgBColorSpace 5 1 1 Buffer only contains the B (Blue component) equivalent to one unsigned char
AL::kHsyColorSpace 6 1 1 Buffer only contains the H (Hue component) equivalent to one unsigned char
AL::khSyColorSpace 7 1 1 Buffer only contains the S (Saturation component) equivalent to one unsigned char
AL::khsYColorSpace 8 1 1 Buffer only contains the Y (Brightness component) equivalent to one unsigned char
AL::kYUV422ColorSpace 9 2 2 Native format, 0xY’Y’VVYYUU equivalent to four unsigned char for two pixels . With Y luma for pixel n, Y’ luma for pixel n+1, and U and V are the average chrominance value of both pixels.
AL::kYUVColorSpace 10 3 3 Buffer contains triplet on the format 0xVVUUYY, equivalent to three unsigned char
AL::kRGBColorSpace 11 3 3 Buffer contains triplet on the format 0xBBGGRR, equivalent to three unsigned char
AL::kHSYColorSpace 12 3 3 Buffer contains triplet on the format 0xYYSSHH, equivalent to three unsigned char
AL::kBGRColorSpace 13 3 3 Buffer contains triplet on the format 0xRRGGBB, equivalent to three unsigned char
AL::kYYCbCrColorSpace 14 2 2 TIFF format, four unsigned characters for two pixels .
AL::kH2RGBColorSpace 15 3 3 H from “HSY to RGB” in fake colors.
AL::kHSMixedColorSpace 16 3 3 HS and (H+S)/2.

Supported Format

Format parameter can have the following values:

Resolution ID Name Resolution ID Value FrameRate Value Description Available on Camera ...
AL::k16VGA 4 1 to 15 2560x1920px Top only
AL::k4VGA 3 1 to 30 1280x960px Top & Bottom
AL::kVGA 2 1 to 30 640x480px
AL::kQVGA 1 1 to 30 320x240px

Note

The camera OV5640 can only run internally from 2560x1920 to 320x240, otherwise scale down is performed (without binning or linear interpolation).

Note

The camera OV5640 can only run internally at 15 or 30fps (except in 2560x1920, 15fps only).