Loss in converting YUV to PNG

1. Does PNG support YUV?
2. What is YUV pixel format?

Does PNG support YUV?

According to Wikipedia, it look like PNG doesn't supports YUV color space, so it must be converted to RGB (and my be converted back almost lossless).

What is YUV pixel format?

YUV formats are divided into packed formats and planar formats. In a packed format, the Y, U, and V components are stored in a single array. Pixels are organized into groups of macropixels, whose layout depends on the format. In a planar format, the Y, U, and V components are stored as three separate planes.