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How Do I Create A Transparent Signature Stamp In PDF?
As pointed out, JPEG cannot hold alpha channel and as such cannot be transparent. You would have to use an editing software, make adjustments and save it as PNG/Webp (for RGB, so screen preview purposes) or TIFF (for CMYK, which you may use for printing). Using a vector format would also work, as it is scalable, however this would require vectorizing the signature (which often enough ends with a more hands-on approach and requires some knowledge on how to create vector objects). As to the approach, it depends on case to case basis. If your JPEG’s background is white, you may try to use channels, namely duplicating the most prominent one, inverting the duplicate, adjusting by curve/levels to achieve a proper mask (in such a way that you increase the contrast between background and actual signature, to remove background noise and enhance the writing), and filling the masked layer with color of your choosing. There are also some sort of online background removers, which may or may not work properly, but you can try to save yourself the hassle.
Sign PDF Online: All You Need to Know
Alternatively, you can visit the “Settings button to view the advanced settings like Signature Quality, etc. when you sign a PDF document, you would need to have a registered email address on Wonder share Document Cloud. If you have a question or need assistance, do not hesitate to call the staff that you reach out to.