An ultra high definition signal processing apparatus and a full high definition television are disclosed. The ultra high definition signal processing apparatus comprises an A/D front end, a video decoder and a video encoder that are orderly connected; an input end of the A/D front end is used for receiving 4K television signals, a video output end of the A/D front end is used for transmitting separated video signals to the video decoder, the video decoder is used for converting the received video signals into corresponding image data, an output end of the video decoder is used for transmitting the converted image data to the video encoder, the video encoder is used for converting the received image data into LVDS signals supported by a screen assembly, and a pixel processor used for adjusting the image resolution ratio of video decoder output is connected in series between the video decoder and the video encoder. By arranging the pixel processor between the video decoder and the video encoder, the problem that high resolution signals cannot be played by a low resolution screen can be solved; by arranged an image recognizer and an image quality processor in the apparatus, each scene can be subjected to real-time and targeted optimization processing operation, and quality of output frames can be improved.