SLIC: Large Receptive Field Learning with Self-Conditioned Adaptability for Learned Image Compression

Recently, transformers are trending as replacements for CNNs in vision tasks, including compression. This trend compels us to question the inherent limitations of CNNs compared to transformers and to explore if CNNs can be enhanced to achieve the same or even better performance than transformers. We want to design a pure CNN based model for compression as most devices are optimized for CNNs well. In our analysis, we find that the key strengths of transformers lie in their dynamic weights and large receptive fields. To enable CNNs with such properties, we propose a novel transform module with large receptive filed learning and self-conditioned adaptability for learned image compression, named SLIC. Specifically, we enlarge the receptive field of depth-wise convolution with suitable complexity and generate the weights according to given conditions. In addition, we also investigate the self-conditioned factor for channels. To prove the effectiveness of our proposed transform module, we equip it with existing entropy models ChARM, SCCTX, and SWAtten and we obtain models SLIC-ChARM, SLIC-SCCTX, and SLIC-SWAtten. Extensive experiments demonstrate our SLIC-ChARM, SLIC-SCCTX, and SLIC-SWAtten have significant improvements over corresponding baselines and achieve SOTA performances with suitable complexity on 5 test datasets (Kodak, Tecnick, CLIC 20, CLIC 21, JPEGAI). Code will be available at https://github.com/JiangWeibeta/SLIC.