The FPGA cannot directly input/output the I/F of TMDS.
If you want to use FPGA for image processing, etc., you need to insert a conversion device between TMDS and FPGA.

The Intel web page has published a document with a block diagram using the Cyclone III.
See Figure 1 in the URL link below.
https://www.altera.com/en_US/pdfs/literature/wp/wp-01018.pdf