Note
FEATURE_PIXEL_ADDRESSING and FEATURE_DECIMATION are equivalent. FEATURE_DECIMATION is a legacy term used by the API.
All PixeLINK Cameras
The Pixel Addressing feature reduces the number of pixels that are read from the ROI.
Pixel Addressing is controlled by two parameters – a Pixel Addressing mode and a value.
The Pixel Addressing mode determines how the number of pixels is reduced. The mode of Pixel Addressing can be decimate (0), averaging (1), binning (2) or resampling (3).
The Pixel Addressing value can be considered as the size of a block of pixels that will be reduced to a 2x2 group. With a Pixel Addressing value of 1, the Pixel Addressing mode has no effect and all pixels in the ROI will be returned. For Pixel Addressing values greater than 1, the number of pixels will be reduced by the square of the value. For example, a Pixel Addressing value of 3 will reduce a 6 x 6 block of pixels to a 2 x 2 block – a reduction of 4/36 or 1/9.
The decimate mode will drop pixels all the pixels in the block except for the top-left group of four. At the highest Pixel Addressing value of 6, a 12 x 12 block of pixels is reduced to 2 x 2. At this level of reduction detail in the scene can be lost and color artifacts introduced.
The averaging mode will average pixels with the similar color within the block resulting in a 2x2 Bayer pattern. This allows details in the blocks to be detected and reduces the effects of color artifacts.
The binning mode will sum pixels with similar color within the block reducing the block to a 2x2 Bayer pattern. Unlike binning with CCD sensors, this summation occurs after the image is digitized so no increase in sensitivity will be noticed but a dark image will appear brighter.
The resampling mode uses a different approach involving the conversion of the Bayer pattern in the blocks to RGB pixels. With a Pixel Addressing value of 1, resampling has no effect. With a Pixel Addressing mode of 2 or more, resampling skips a bayer to RGB conversion step and converts the block of 10-bit pixels to one 30-bit RGB pixel by averaging the red, green and blue channels. Setting the video format to YUV422 mode will result in the best image quality while resampling. Resampling will create images with the highest quality and the least artifacts.
Pixel Addressing will reduce the amount of data coming from the camera. However, only the Decimate mode will permit an increase in the frame rate. Averaging, binning and resampling modes will have the same frame rate as if the Pixel Addressing value was 1 (no decimation.)
Pixel Addressing works in the same fashion with color or monochrome sensors.
PxLGetFeature, PxLSetFeature
|
Feature ID |
Number of Parms |
Parameters |
Units |
Restrictions |
|
FEATURE_PIXEL_ADDRESSING Reduction of the image data |
2 |
fValue |
N/A |
Integer only |
|
fMode |
N/A |
Integer only |
|
|
|
Note |
FEATURE_PIXEL_ADDRESSING and FEATURE_DECIMATION are equivalent. FEATURE_DECIMATION is a legacy term used by the API. |
|
|
|
Note |
The stream state must be off (STREAM_OFF) to modify this feature. See PxLSetStreamState. For IIDC programmers, see Transmitting Video. |
|
Camera |
Presence |
Read Only |
Auto |
Manual |
One-time Auto |
Off |
CiD |
|
All cameras |
Yes |
No |
No |
Yes |
No |
Yes |
Yes |
|
Camera |
Parameter |
Unit |
Type |
Min |
Max |
Default |
Step Size |
Comments |
|
741, 681M |
Mode |
None |
Absolute |
0 |
0 |
0 |
1 |
0: Decimate |
|
Value |
None |
Absolute |
1 |
2 |
1 |
1 |
| |
|
742, 681C |
Mode |
None |
Absolute |
0 |
3 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
2 |
1 |
1 |
| |
|
771, 621M |
Mode |
None |
Absolute |
0 |
2 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin |
|
Value |
None |
Absolute |
1 |
2 |
1 |
1 |
| |
|
761 |
Mode |
None |
Absolute |
1 |
2 |
1 |
1 |
1: Average, 2: Bin |
|
Value |
None |
Absolute |
1 |
4 |
1 |
1 |
Pixel Addressing Value of 3 is not supported | |
|
762 |
Mode |
None |
Absolute |
1 |
3 |
1 |
1 |
1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
4 |
1 |
1 |
Pixel Addressing Value of 3 is not supported | |
|
774, 622 |
Mode |
None |
Absolute |
0 |
3 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
2 |
1 |
1 |
| |
|
776, 623 778, 625C |
Mode |
None |
Absolute |
0 |
3 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
4 |
1 |
1 |
Pixel Addressing Value of 3 is not supported | |
|
777 625M |
Mode |
None |
Absolute |
0 |
2 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin |
|
Value |
None |
Absolute |
1 |
4 |
1 |
1 |
Pixel Addressing Value of 3 is not supported | |
|
781, 686M |
Mode |
None |
Absolute |
0 |
2 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin |
|
Value |
None |
Absolute |
1 |
6 |
1 |
1 |
Pixel Addressing Value of 5 is not supported | |
|
782, 686C |
Mode |
None |
Absolute |
0 |
3 |
0 |
1 |
0: Decimate, 1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
6 |
1 |
1 |
Pixel Addressing Value of 5 is not supported | |
|
870, 950 |
Mode |
None |
Absolute |
0 |
3 |
0 |
1 |
1: Average, 2: Bin, 3: Resample |
|
Value |
None |
Absolute |
1 |
4 |
1 |
1 |
Pixel Addressing Value of 3 is not supported |
Pixel Addressing is only available with Format 7 video formats. The Format 7 modes select the pixel addressing value with Format 7 Mode 0 having a pixel addressing value of 1 (no effect). To set the pixel addressing value, enable appropriate the Format 7 Mode and then set the Pixel Addressing Mode using the Advanced CSR below.
|
|
|
Note |
Note that the PixeLINK API and drivers will only recognize cameras using Format 7 Mode 0 and will only set Format 7 Mode 0 regardless of the Pixel Addressing feature settings. A FireWire camera with saved settings (see Memory Channel) with Pixel Addressing enabled may not be recognized properly by 3rd party IIDC software. If moving a FireWire camera between the PixeLINK API and 3rd party IIDC software, be sure to use the factory defaults or to save settings with no Pixel Addressing (Value = 1). |
Information in this section is based on the IIDC 1.31 specification. Please refer to the IIDC 1.31 specification for details on the meanings and use of CSRs.
The following table describes the Advanced Feature CSRs that are allowed under the IIDC V1.31 specification as vendor specific. These CSRs are based at an offset found in the Advanced Feature Offset value (register 0x480).
This table is common for all IIDC compliant PixeLINK cameras. See the full table in the IIDC Overview - Advanced CSRs topic.
|
Offset |
Name |
Field |
Bit |
Description |
|
ADVANCED FEATURE INQUIRY REGISTERS (READ ONLY) |
||||
|
114h |
Pixel Addressing Inquiry |
Presence_Inq |
[0] |
Presence of this feature |
|
In_Desc_Inq |
[1] |
Can this feature have different values in different descriptors 1 = Yes, 0 = No | ||
|
|
[2..3] |
Reserved | ||
|
Mode0_Inq |
[4] |
Presence of Pixel Addressing Mode 0 (e.g. decimation) | ||
|
Mode1_Inq |
[5] |
Presence of Pixel Addressing Mode 1 (e.g. averaging) | ||
|
Mode2_Inq |
[6] |
Presence of Pixel Addressing Mode 2 (e.g. binning) | ||
|
Mode3_Inq |
[7] |
Presence of Pixel Addressing Mode 3 (e.g. resampling) | ||
|
Base |
[8..15] |
Base for Pixel Addressing. Maximum Pixel Addressing is Base^Max_Value (except when Base = 1 then it is Max_Value) | ||
|
Max_Value |
[16..31] |
The maximum value for the Pixel Addressing variable | ||
|
ADVANCED FEATURE CONTROL REGISTERS |
||||
|
204h |
Pixel Addressing |
Value |
[0..15] |
Value for Pixel Addressing. Actual reduction is Base^Value except when Base = 1 then it is Value (Format 7 only) |
|
|
[16..23] |
Reserved | ||
|
Mode |
[24..31] |
Pixel Addressing mode | ||