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[ Electrical Division : IMX249 Camera Specification ]

Created by [ Rowan Dempster] on Dec 27, 2019

The WATonomous team uses the [BFLY-PGE-50S5C-C]{.inline-comment-marker data-ref=”0663d3be-e628-4f10-97a2-ef8f4941b7a0”}, aka [Sony IMX249]{.inline-comment-marker data-ref=”6f403554-0d3e-4676-b3ac-3a7b3cd4b1bb”}, cameras.


Specification Details Firmware 1.54.3.0 Resolution 1920 x 1200 Frame Rate 41 FPS Megapixels 2.3 MP Chroma Color Pixel Size 5.86 μm Lens Mount C-mount ADC 10-bit/12-bit in Mode 7 Gain Range 0dB - 29.996dB Exposure Range 0.019ms - 32s Trigger Modes Standard, bulb, overlapped, multi-shot Partial Image Modes Pixelbinning, decimation, ROI Image Processing Gamma, lookup table, hue, saturation, sharpness HDR Sequencing 4 x exposure, 4 x gain Image Buffer 16 MB User Sets 2 user configuration sets for custom camera Flash Memory 512 KB non-volatile memory Opto-isolated I/O Ports 1 input, 1 output Auxiliary Output 3.3 V, 120 mA maximum Interface GigE PoE Power Requirements 12V nominal, with 5-16V range via GPIO interface Power Consumption 2.5W maximum Dimensions 29mm x 29mm x 30mm Mass 36g Machine Vision Standard GigE Vision v1.2 Temperature Operating: 0° - 45°, Storage: -30° - 60° Humidity, (no condensation) Operating: 20%-80%, Storage: 20%-95% Warranty 3 years —————————– ————————————————–

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Camera Attributes

Pixel Formats

Pixel formats are encoding schemes used to convert raw image data to color or monochrome images.


Pixel Format Bits per Pixel Mono 8, Raw 8 8 Mono 12, Raw 12, YUV 411 12 Mono 18, Raw 16, YUV 422 16 RGB 8, YUV 444 24 ————————– ——————–

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Raw

Raw is a pixel format where the image data is Bayer Raw and not processed by any on board processing. No image processing will be done (FPGA/color core skipped), and this allows for faster frame rates. To select Raw format in GenICam, disable On Board Color Processing under Image Format Control.

Mono

The image data is monochrome. Since IMX-249 is a color camera, using this format will enable FPGA/Color Core image processing such as changing the Gamma/LUT
Y8 and Y16 are also monochrome formats with 8 and 16 bits per pixel respectively.

RGB

A color-encoding scheme representing the intensities of Red, Green and Blue channels of each pixel. Each channel uses 8 bits, totalling 24 bits.

YUV

A color-encoding scheme that includes brightness (Y) and color (UV) values for each pixel.
YUV 444 - High resolution, with each of Y, U and V using 8 bits.
YUV 422 - Medium resolution with 16 bits per pixel. 8 bits is used for Y value, and UV values are shared across 2 pixels. This reduces the bandwidth of an uncompressed video signal by 33% without noticeable visual differences.
YUV 411 - Low resolution with 12 bits per pixel. Y value takes up 8 bits, and UV values are shared across 4 pixels. Bandwidth is reduced by half as compared to YUV 444, and less color information is recorded.
This camera uses packed (instead of planar) YUV. This means YUV values are stored in a single array, pixels are organized into groups of macropixels.

JPEG

It supports 16.7 million colors and there is a degree of compression that can be adjusted to balance between image size and image quality.

Video Modes

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Mode Description Frame Rate Increase Brightness Increase 0 All Pixel Scan N/A N/A 4 2x2 Adjacent Binning Yes No 7 Optical Imaging No No ———- ———————- ————————- ————————-

The above table only contains modes that are available on the BFLY-PGE-2356C-C.

Mode 0

It is the standard imaging mode with full resolution readout and global shutter.

Mode 4

This mode is 2x2 binning. Vertical binning occurs in the sensor while horizontal binning occurs in the FPGA. This reduces image quality but increases frame rate and image brightness.

Mode 7

Rolling shutter is applied, and is used for specifying a region of interest using a 12-bit ADC. Maximum exposure time is only possible using this mode.

Frame Rates

Other than using video modes to increase frame rates, Jumbo Frames can be enabled with the GigE Configurator for increase d frame rates as well.

Maximum Possible Frame Rate

''FPS = (Bandwidth / (W * H * Bytes Per Pixel)) / # Cameras''
The Bytes Per Pixel is related to the Pixel Format as follows.


Pixel Format Bytes Per Pixel 8-bit 1 12-bit 1.5 16-bit 2 24-bit 3 —————— ———————

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For the BFLY-PGE-2356C, refer to the following table


Pixel Format 1920 x 1200 1844 x 1002 1844 x 802 1844 x 602 1844 x 402 8-bit 41.5 49.3 60.8 79.3 114.1 12-bit 32 39.9 49.3 66.1 98.77 16-bit 23.9 30 37.2 49.3 74.7 24-bit 16 20 25 33.2 49 —————— —————– —————– —————- —————- —————-

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Global Shutter

For each frame, all of the lines are exposed for the same amount of time. They start and end together. This captures frames with a more uniform brightness and minimal motion blur. After exposure, each line is readout sequentially and each line's readout time is identical.

Gain

Gain is the amount o amplification applied to the pixels by the ADC. It can increase brightness and sharpening processes, but introduces more noise.

Exposure

The exposure can be controlled within the range of 0.019ms to 3.9s. If the exposure time is not constant, the auto exposure mode may be on.
The camera will continuously expose and read image date from the sensor if it is powered up and is free-running (not in trigger mode). In free-running mode, changes in exposure takes effect only after a photo or two from the current frame.

Auto Exposure

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State Description Condition Off Exposure control done via setting both exposure and gain Auto Exposure OFF OR Exposure and Gain OFF Manual Exposure Control Camera automatically modified Exposure and Gain to try and match the average image intensity to the Auto Exposure value. Auto Exposure OFF AND/OR Exposure and Gain to Continuous Example Camera automatically changes the average image intensity value to produce a visually pleasing image. Auto Exposure, Exposure and Gain to Continuous ————————- ————————————————————————————————————————– ———————————————————-

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Factor Effect on Auto Exposure Auto Exposure Range Range of allowable exposure times can be specified Auto Shutter Range User can set the range of exposure within the allowed range Auto Exposure Gain User can set the range of gain within the allowed gain Auto Exposure ROI User can set the ROI within the full image to be used for both white balance and exposure. This ROI is relative to the transmitted image (not necessarily RAW). Entire image will be used if erroneous values are given ——————— —————————————————————————————————————————————————————————————————————————–

Sharpness

Sharpness can be altered by filtering the image edges. '''It is disabled when the camera is outputting raw Bayer data.''' Values larger than 1000 sharpens the image and values lower than 1000 blurs the image.

Gamma and Lookup Table (LUT)

While sensors in the cameras are relatively linear, meaning the intensity of pixel increases linearly with the number of photos hitting the sensor, a non-linear mapping can be given. Value between 0.5 and 1 decreases the brightness, and values 1 to 4 increases the brightness. '''The default value of Gamma is 1.25. Disable Gamma for a linear mapping.'''

'''When Gamma is enabled, LUT is disabled and vice versa.'''
Users can also set the LUT directly, and the values will be stored on the camera itself. However, the Gamma option should be employed instead for simplicity sake.

Troubleshooting

Relevant Camera Diagnostics Parameters

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Parameter Description Time from Initialize This gives the time (in s), since the camera was initialized. This only occurs when a hard power-up is done, not just a power-up. Link Up Time This gives the time (in s) since the last Ethernet reconnection occurs. The network is fine if this value equals the time from initialize. Transmit Failure Number of failed frame transmission since the last reset. Camera Log A 256-byte log. Interpretation requires help from the technical support team. ———————- ——————————————————————————————————————————————–

Status Register LED

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LED Status Description Off Not receiving power Steady green, high intensity (~5s) Camera powered up Green/Red flashing (~2s) Camera programs the FPGA Green flashing quickly, low intensity Establishing an IP connection in the following order 1) One green blink 1) A persistent IP address if available and enabled 2) 2 green blinks 2) A DHCP address, if available and enabled 3) 3 green blinks 3) An link-local address 4) 3 red blinks 4) Failure to establish connection Steady green, high intensity Camera is streaming images Red/green flashing quickly Firmware update in progress Red flashing slowly Error ————————————— ——————————————————

Smear Reduction

When a bright light is shone relatively direct on the camera, images may be smeared (faint bright line extending across image).
To reduce smear when the light source cannot be controlled:

Document generated by Confluence on Nov 28, 2021 22:40

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