VLC DEBLOCKING FILTER SOFTWARE

VLC DEBLOCKING FILTER SOFTWARE

Gary Sullivan, in Handbook of Image and Video Processing (Second Edition), 2005 3.4 MPEG-4: Video ApplicationsДЄlthough early industry adoption of MPEG-4 Part 2 was significantly slowed down by initial licensing terms that were considered unattractive for some applications, many companies now commercialize a variety of MPEG-4 Part 2 software and hardware products. BSAC enables the decoder to stop anywhere between 16 Kbit/s and the bit rate arranged in 1 Kbit/s steps.Д«erna Erol.

In addition, the introduction of bit-sliced arithmetic coding (BSAC) offers noiseless transcoding of an AAC stream into a fine-granule scalable stream between 16 and 64 Kbit/s per channel. One is referred to as the twin-vector quantization (VQ), which makes combined use of an interleaved VQ and Linear Predictive Coding (LPC) spectral estimation. T/F coding is developed based on the coding tools used in MPEG-2 AAC with some add-ons. T/F coding is typically applied to the bit rates starting at about 16 Kbit/s for audio signals with bandwidths above 8 kHz. For audio signals sampled at 8 and 16 kHz, CELP coding offers good quality at medium bit rates between about 6 and 24 Kbit/s. For speech signals sampled at 8 kHz, parametric coding is used to achieve targeted bit rates between about 2 and 6 Kbit/s. The MPEG-4 standard defines three types of coders: parametric coding, code-excited linear predictive (CELP) coding, and time/frequency (T/F) coding. The MPEG-2 ACC tool set within the MPEG-4 standard supports the compression of natural audio at bit rates ranging from 2 up to 64 Kbit/s. The MPEG-4 standard, which was finalized in 1999, integrates the whole range of audio from high-fidelity speech coding and audio coding down to synthetic speech and synthetic audio. Thus, the absolute (frame) coordinate system is used to define such bounding boxes.Д¬HI-MIN LIU, WEN-WHEI CHANG, in Multimedia Communications, 2001 4.2.3 MPEG-4 Note that the shape, size, and location of this bounding box can change from one time instance to another.

An exterior MB, on the other hand, lies completely outside the VOP. An internal MB lies completely inside the VOP, whereas a boundary MB lies on the contour of the VOP i.e., parts of it are inside the VOP and the other parts are outside the VOP.

Within this bounding box, there are three types of MBs: internal MBs, boundary MBs, and exterior MBs. This bounding box is illustrated for the Balloon VOP in Figure 3.11. This bounding box is chosen such that it completely contains the VOP but uses the minimum number of macroblocks. To achieve efficient encoding, the arbitrary shaped VOP is first encapsulated within a bounding box. Thus, an MB consists of six 8 Г— 8 blocks: four luma blocks and two corresponding chroma blocks. MPEG-4 supports a 4:2:0 subsampling format with 4вЂ“12 bits/sample. In fact, the MPEG-4 standard provides measures to ensure some level of interoperability with MPEG-1/2 and H.263.ДЄ VOP is encoded on a macroblock (MB) basis. When a frame is encoded using a single VOP, this generic representation degenerates into the special case of rectangular frames and an MPEG-4 encoder becomes almost identical to an H.263 encoder. Note that this object-based representation can be thought of as a generic representation. The difference here is that the encoded entities can have arbitrary shapes rather than the fixed rectangular frame shape, and therefore additional shape information needs to be encoded and transmitted. In fact, for most cases, the texture encoder is DCT-based and the structure is very similar to the conventional hybrid MC-DPCM/DCT encoder. Note that the structure of this encoder is very similar to the MC-DPCM structure utilized by H.263 and most other standards. As can be seen, an MPEG-4 VOP encoder has three main functionalities: shape encoding, motion encoding (along with motion estimation and compensation), and texture encoding. In addition to composition information (which indicates where and when the VOP is to be displayed), each VOP is encoded in terms of its shape, motion, and texture.

Vlc deblocking filter