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wiki:v2:some_tips_on_generating_color_signatures_2 [2018/05/23 22:27] pixycam |
wiki:v2:some_tips_on_generating_color_signatures_2 [2018/09/28 19:58] (current) jfrench Imported by DokuWiki Advanced Plugin |
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You can adjust all seven color signatures this way to maximize detection accuracy. Be sure to press **Apply** or **OK** to save the slider ranges! The adjusted values won't be saved if you press **Cancel** or dismiss the dialog. | You can adjust all seven color signatures this way to maximize detection accuracy. Be sure to press **Apply** or **OK** to save the slider ranges! The adjusted values won't be saved if you press **Cancel** or dismiss the dialog. | ||
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+ | ==== Adjust minimum frames per second ==== | ||
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+ | Adjusting the **Min frames per second** slider in the **Camera** tab to smaller values can improve the image quality by reducing the noise and/or improving the exposure in low-light environments. The disadvantage of reducing the frames per second is that it reduces Pixy2's update rate. | ||
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+ | {{wiki:v2:image_506.png}} | ||
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+ | The two pictures below show a low-light scene and the reduction in noise by reducing the frames per second. (The left frame is higher fps, more noise.) | ||
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+ | {{wiki:v2:image_507.png?350|Higher fps, more noise}} | ||
+ | {{wiki:v2:image_509.png?350|Lower fps, less noise}} | ||
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+ | ==== Increase block filtering ==== | ||
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+ | Pixy2 uses filtering to determine if a given block is likely to be valid or just a false positive detection. Increasing the **Block filtering** in the **Expert** tab can reduce the number of false positive detections. The cost of increasing the block filtering is longer latency when detecting new objects. That is, it will take Pixy2 longer to report detection of a new object and add it to the list of tracked objects. Once an object is added to Pixy2's list of tracked objects, the position of each object is not filtered so that the dynamics of the object's reported position/motion isn't affected. | ||
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+ | {{wiki:v2:image_522.png}} | ||
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Like a camera, Pixy2 needs to get the correct exposure setting or its images won't contain enough dynamic range, and detection accuracy will suffer. PixyMon has a feature that highlights regions of the image that are overexposed. You can enable it by clicking on the box next to **Highlight overexposure** in the **PixyMon Parameters** tab (see below). | Like a camera, Pixy2 needs to get the correct exposure setting or its images won't contain enough dynamic range, and detection accuracy will suffer. PixyMon has a feature that highlights regions of the image that are overexposed. You can enable it by clicking on the box next to **Highlight overexposure** in the **PixyMon Parameters** tab (see below). | ||
- | {{wiki:img:6e0753847f2cb647409312f25cd109d4743c54c7.jpg?400}} | + | {{wiki:v2:image_218.png}} |
When this is enabled, overexposed parts of the image will be highlighted as black, as shown below: | When this is enabled, overexposed parts of the image will be highlighted as black, as shown below: | ||
- | {{wiki:img:d777a70b0e3c2e701f27e1a54293a89e8b4bb638.jpg?400}} | + | {{wiki:v2:image_217.png}} |
We highly recommend enabling overexposure highlighting, because if the object you want to detect is overexposed, detection accuracy will suffer. So, after enabling overexposure highlighting, go to the **Tuning** tab in **Pixy Parameters** and choose a good setting for **Camera Brightness** by adjusting the slider (see below). | We highly recommend enabling overexposure highlighting, because if the object you want to detect is overexposed, detection accuracy will suffer. So, after enabling overexposure highlighting, go to the **Tuning** tab in **Pixy Parameters** and choose a good setting for **Camera Brightness** by adjusting the slider (see below). | ||
- | {{wiki:img:65a67a4cd1aa9fe49575f34a0dd638aec24d8afb.jpg?400}} | + | {{wiki:v2:image_221.png}} |
- | A good exposure setting leaves almost all of the pixels in your object correctly exposed, but not too dark (underexposed). It's OK for small parts of your object to be overexposed, especially if your object is shiny. See the picture below -- note that a small part of the object (yellow ball) has a black region indicating overexposure. This is fine. | + | A good exposure setting leaves almost all of the pixels in your object correctly exposed, but not too dark (underexposed). It's OK for small parts of your object to be overexposed, especially if your object is shiny. See the picture below -- note that a small part of the object (red ball) has a black region indicating overexposure. This is fine. |
- | {{wiki:img:540b3dabc96bcaf5cb1856b09e419a4e832a29bc.jpg?400}} | + | {{wiki:v2:image_220.png}} |
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==== Adjust the signature teach threshold ==== | ==== Adjust the signature teach threshold ==== | ||
- | One of Pixy2's goals is to be able to easily learn different objects without needing to hook it up to a computer. The button-press teaching method allows you to do this. But for certain objects and/or lighting conditions, the button-press method might need some adjusting. The **Signature teach threshold** setting in the **Expert** tab allows you to adjust how inclusive Pixy2 is when determining which pixels are part of the object during teaching. You can adjust the **Signature teach threshold** while Pixy2 is in teach mode, so you can get "live" feedback while choosing a good threshold. The video below shows the **Signature teach threshold** in action. | + | One of Pixy2's goals is to be able to easily learn different objects without needing to hook it up to a computer. The button-press teaching method allows you to do this. But for certain objects and/or lighting conditions, the button-press method might need some adjusting. The **Signature teach threshold** setting in the **Expert** tab allows you to adjust how inclusive Pixy2 is when determining which pixels are part of the object during teaching. You can adjust the **Signature teach threshold** while Pixy2 is in teach mode, so you can get "live" feedback while choosing a good threshold. |
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+ | {{wiki:v2:image_230.png}} | ||
- | {{youtube>tJ7CZfvsbz8?480x360)}} | + | The picture below is an example of a threshold that is too inclusive. Note the regions that are not part of the green duck (the intended object). In this case, you should reduce the threshold. |
- | {{wiki:img:96850007a4625a986b35498b8eb11450232fb235.jpg?400}} | + | {{wiki:v2:image_235.png}} |
- | The picture below is an example of a threshold that is too inclusive. Note the regions that are not part of the purple dinosaur (the intended object). In this case, you should reduce the threshold. | + | The picture below is an example of a threshold that is not inclusive enough. Note that the regions do not include much of thegreen duck. In this case, you should increase the threshold. |
- | {{wiki:img:5ad10fe37bce71897bf181fee9077186af974a9c.jpg?400}} | + | {{wiki:v2:image_238.png}} |
- | The picture below is an example of a threshold that is not inclusive enough. Note that the regions do not include much of the purple dinosuar. In this case, you should increase the threshold. | + | The picture below is an example of a good threshold. |
- | {{wiki:img:8a6cd13952d3307cb98ba56df1c334b980c64f9b.jpg?400}} | + | {{wiki:v2:image_231.png}} |