Image Bit Errors - Nokia RM-57 Service Manual

RM-57/58
Camera Module Troubleshooting Nokia Customer Care
Figure 82 Image taken with clean protection Figure 83 Image taken with greasy protection window
window

Image bit errors

Bit errors are image defects caused by data transmission errors between the camera module and the phone
baseband and/or errors inside the module.
Usually bit errors can be easily detected in images, and they are best visible in full resolution images. A good
practice is to use a uniform white test target when analysing these errors. The errors are clearly visible, colourful
sharp dots or lines in camera images. See the following figure.
Figure 84 Bit errors caused by JPEG compression
One type of bit error is a lack of bit depth. In this case, the image is almost totally black under normal conditions,
and only senses something in very highly illuminated environments. Typically this is a contact problem between
the camera module and the phone main PWB. You should check the camera assembly and connector contacts.
If the fault is in the camera module, bit errors are typically visible only when using some specific image
resolution. For example, in case of a viewfinder fault, the error might exist but is not visible in a full size image.
Camera troubleshooting flowcharts
Camera hardware failure message troubleshooting
Context
If you get a hardware failure message when using the camera, follow the next troubleshooting flowchart.
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