PNG format cannot lose color or quality.It can only change the file size depending on the compression algorithms and filters (all lossless).
@r-bin This is an incorrect statement. While PNG is a lossless format, saving a 24bit image as a 8bit indexed PNG file WILL lose colours and quality (for example). Saving a 32bit per channel rendered image as 16bit per channel PNG file will also have a negative impact on the full dynamic range of the original rendered image.
Neither example has anything to do with compression or filters.