Artifacts could include:
Strange lines, rainbow blotches, grid pattern etc.
If you are seeing strange looking artifacts in JPEG to RAW AI please open your preferences, and switch from Processing Mode: GPU (bottom of the list shown in the image that is not greyed out)
to Processing Mode: CPU
This will make the processing happen on your CPU instead of your GPU.
The processing will be much slower on the CPU but it is much less likely to produce artifacting.
Since most images most of the time do not produce artifacts, for speed you will want to stick with GPU mode most of the time,
but for images that do produce artifacting, running in CPU mode will nearly always fix this.
If you can't get the results you want from either switching to CPU mode or GPU mode for a certain image, try exporting the image as a different file type and processing again.
Some images may already be very low quality, have lots of image compression or other things interfering with our algorithm. If after switching to CPU mode you still get artifacts for a particular image, please feel free to send it to us using our Help Center so our image processing developers can study it and build our next release to better serve that type of image.