Content-Based Image Compression for Arbitrary-Resolution Display Devices
The work presented in this paper addresses the increasing demand of visual signal delivery to terminals with arbitrary resolutions (like in mobile multimedia communication and cloud computing) for universal access and presentation, without extra computational burden to the receiving end. Scalable image compression and transmission are essential, and to be effective and meaningful, it has to be content-based. The existing coding methods cannot support content-based spatial scalability with high compression. In this paper, the principle of seam carving (SC) is incorporated into a wavelet codec. After multi-level discrete wavelet transform (DWT), SC is performed in the low frequency subband. Different from the conventional wavelet-based coding schemes, DWT coefficients here are encoded and transmitted according to the energy map of resultant seams. At the decoder side, the end user has the ultimate choice for the scalability without the need to examine the visual content; an image with arbitrary aspect ratio can be reconstructed in a content-aware manner based upon the encoded information. Simulation results show that the resized images preserve important content while achieving high coding efficiency in transmission.