ViSTRA2: Video coding using spatial resolution and effective bit depth adaptation

We present a new video compression framework (ViSTRA2) which exploits adaptation of spatial resolution and effective bit depth, down-sampling these parameters at the encoder based on perceptual criteria, and up-sampling at the decoder using a deep convolution neural network. ViSTRA2 has been integrated with the reference software of both the HEVC (HM 16.20) and VVC (VTM 4.0.1), and evaluated under the Joint Video Exploration Team Common Test Conditions using the Random Access configuration. Our results show consistent and significant compression gains against HM and VVC based on Bjønegaard Delta measurements, with average BD-rate savings of 12.6% (PSNR) and 19.5% (VMAF) over HM and 5.5% (PSNR) and 8.6% (VMAF) over VTM. •A new video compression framework (ViSTRA2) which exploits adaptation of spatial resolution and effective bit depth.•ViSTRA2 down-samples these parameters at the encoder based on perceptual criteria, and upsampling at the decoder using a deep convolution neural network.•It has been integrated with HEVC and VVC and show consistent and significant coding gains.