A 0.76 mm2 0.22 nJ/Pixel DL-Assisted 4K Video Encoder LSI for Quality-of-Experience Over Smartphones

This letter proposes the world'sfirst deep learning (DL)assisted video encoder LSI fabricated in a 10-nm process with a core area of 0.76 mm2 to integrate quad-core DL accelerators and 4K×2K H.264/H.265 video encoders. A visual-contact-held network (VCFNet) DL model is newly designed to predict human focus information with extraordinary reduction of encoding complexity, leading to 82.3% power reduction. Moreover, input channel reduction and layer merging approaches reduce VCFNet complexity by 69%. Operated at 0.9 V and 504 MHz, the proposed DL-assisted 4K video encoder LSI consumes 56.54 mW to achieve 0.22 nJ/pixel of energy efficiency, cutting 0.1-14 nJ/pixel compared to conventional designs.