|
Recent advances in signal processing combined
with an increase in network capacity are paving the way for users to enjoy
services wherever they go and on a host of multimedia capable devices.
Each of these terminals may support a variety of different formats. Furthermore,
the networks that they are connected to are often characterized by different
network conditions, and the terminals themselves vary in display capabilities,
processing power and memory capacity. Given such a dynamic environment,
it becomes necessary to consider methods of adapting the content accordingly.
This talk focuses on the general problem
of reduced-resolution transcoding, and more specifically on the conversion
between MPEG-2 and MPEG-4. This technology enables broadcast-quality video
streams to be transmitted, decoded and displayed on low-cost mobile devices.
Technical topics include:
- analysis of drift errors when transcoding to a lower spatial resolution
- presentation of various architectures to overcome sources of drift
- macroblock-level conversions, e.g., MV mapping, texture down-sampling
- rate control and bit allocation issues
- evaluation of complexity and quality
Anthony Vetro is with Mitsubishi Electric
Research Labs in Murray Hill, NJ, where he is currently a Principal Member
of the Technical Staff. He received the Ph.D. degree in Electrical Engineering
from Polytechnic University in Brooklyn, NY, and his main research interests
are in the areas video coding and transmission, with emphasis on content
scaling and rate allocation. He has also been an active participant in
MPEG standards for several years.
|