Do Nyeon Kim

Current video coding standards: H.264/AVC, Dirac, AVS China and VC-1

Video coding standards: H.264/AVC, DIRAC, AVS China and VC-1 are presented. These are the latest standards and are adopted by ITU-T/ISO-IEC, BBC, China standards organization and SMPTE respectively. Besides presenting these standards, research potential and as well projects (both at UG and grad levels) are emphasized. These are available by accessing the database for research and projects in [18]. Web/ftp sites for accessing standards documents, software, test sequences, conformance bit streams, industry activities etc are provided.

H.264/MPEG-4 Advanced Video Coding

Similar to AVS China ( Chap. 3), the profiles, levels and functionalities of H.264/AVC are described. The roles of various blocks in the encoder and decoder, from a video compression view point, are addressed. The similarities and differences between AVS China and H.264/AVC can be observed.

Two-dimensional discrete sine transform scheme for image mirroring and rotation

Mirroring an image (horizontally or vertically) and rotation by 90, 180, and 270 deg in the spatial domain is implemented by changing the signs of the 2-D discrete cosine transform (DCT) co- efficients of the original image appropriately. This approach leads to an efficient compressed domain-based image mirroring and rota- tion. This method is now extended to a 2-D discrete sine transform (DST), i.e., a 2-D DST possesses properties similar to 2-D DCT and it can be applied to image mirroring (horizontally or vertically) and also rotation by angles of 90, 180, and 270 deg. We illustrate these methods in a video-editing application.

High Efficiency Video Coding(HEVC)

HEVC the latest standard is presented. Comparison with H.264/AVC ( Chap. 4) is cited. The focus is on overview of HEVC rather than a detailed description of tools and techniques that constitute the encoder. A plethora of projects listed at the end challenges the implementation and futher research related to HEVC.

Two-Dimensional Discrete Fourier Transform

Two-dimensional DFT has applications in image/video processing. The extension from 1-D to 2-D for the DFT is straightforward.

Direct converting DV into MPEG-2 intra coding

Converting the digital video (DV) format for digital video cassette recorders into the MPEG-2 intra coding is performed in the DCT domain to reduce conversion steps. To convert the 4:1:1 to the 4:2:2 chroma. formats and the 2-4-8 DCT mode to the 8-8 DCT mode, a matrix is multiplied by transformed data. Such multiplication enables parallel processing, and the m_quant of the MPEG-2 TM5 rate control is computed in the DCT domain.

IMAGE MIRRORING AND ROTATION IN THE WAVELET DOMAIN

JPEG2000, the international standard for still image compression, uses wavelet transform. The filters used by JPEG2000 for transformation are the 9/7 Daubechies filter and the 5/3 Le Gall filter. In this paper, we present a method for image mirroring and rotation in the wavelet domain, by manipulating the transformation coefficients. Our technique requires no additional complexity and the perfect reconstruction property is preserved.

Image mirroring, rotation, and interpolation in wavelet domain

JPEG2000, the international standard for still image compression, uses wavelet transform. JPEG2000 uses the 9/7 Daubechies filter and the 5/3 Le Gall filter for transformation. In this paper, we present a method for image mirroring and rotation in the wavelet domain, by manipulating the transformation coefficients. Our technique requires no additional complexity and the perfect reconstruction property is preserved. The paper also discusses a method to achieve image interpolation, which constructs a higher resolution image from a lower resolution one. The wavelet domain coefficients of the image are utilized for the same. For comparison purposes, the low frequency components obtained after the wavelet transform of the image are considered as the low resolution image. Then we predict the rest of the components in order to reconstruct the higher resolution image. The reconstructed image is then compared with the original image.

VP6 Video Coding Standard

Encoder/decoder details on VP6 developed by On2 Technologies are provided. Similarities related to functionalities between H.264 ( Chap. 4) and VP6 are highlighted and differences such as golden frames are pointed out. Resources related to VP9 open source video codec by Google (Google acquired On2 Technologies in 2010) are also addressed.

The VC-1 Video Coding

As with other codecs, encoder/decoder details on VC-1 are described. VC-1 is an SMPTE standard based on WMV9 developed by Microsoft. H.264/AVC to VC-1 transcoder is outlined. The intra frame coding only of Dirac ( Chap. 7) is adopted by SMPTE as VC-2.