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In recent years, real-time video communication over the internet has been widely utilized for applications like video
conferencing. Streaming live video over heterogeneous IP networks, including wireless networks, requires video coding
algorithms that can support various levels of quality in order to adapt to the network end-to-end bandwidth and
transmitter/receiver resources. In this work, a scalable video coding and compression algorithm based on the Contourlet
Transform is proposed. The algorithm allows for multiple levels of detail, without re-encoding the video frames, by just
dropping the encoded information referring to higher resolution than needed. Compression is achieved by means of lossy
and lossless methods, as well as variable bit rate encoding schemes. Furthermore, due to the transformation utilized, it
does not suffer from blocking artifacts that occur with many widely adopted compression algorithms. Another highly
advantageous characteristic of the algorithm is the suppression of noise induced by low-quality sensors usually
encountered in web-cameras, due to the manipulation of the transform coefficients at the compression stage. The
proposed algorithm is designed to introduce minimal coding delay, thus achieving real-time performance. Performance is
enhanced by utilizing the vast computational capabilities of modern GPUs, providing satisfactory encoding and decoding
times at relatively low cost. These characteristics make this method suitable for applications like video-conferencing that
demand real-time performance, along with the highest visual quality possible for each user. Through the presented
performance and quality evaluation of the algorithm, experimental results show that the proposed algorithm achieves
better or comparable visual quality relative to other compression and encoding methods tested, while maintaining a
satisfactory compression ratio. Especially at low bitrates, it provides more human-eye friendly images compared to
algorithms utilizing block-based coding, like the MPEG family, as it introduces fuzziness and blurring instead of
artificial block artifacts.
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