The Trademark Office has regulations:

The file format of the trademark pattern should be jpg, the graphics should be clear, the size of the pattern file should be less than 200KB and the pixels of the graphics should be between "400×400"-"1500 ×1500”. If the trademark pattern is obtained by scanning, the graphics should be scanned in 24-bit color, RGB format, and 300dpi resolution and comply with trademark laws and regulations (clear graphics, larger than 5×5 cm and smaller than 10×10 cm). The applicant (or agent) should ensure that the color depth (or grayscale) of the scanned graphic is consistent with the original graphic. Otherwise, the clarity of the graphic on the Trademark Registration Certificate may be affected.

If you apply for trademark registration with a color combination or colored pattern, you should upload the colored pattern and black and white draft respectively. If the color is not specified, a black and white pattern should be uploaded.