About VISUALmpeg
Those who are familiar
with MPEG know the typical MPEG parameters and expressions such as:
· I, B, P frames
· Macroblocks
· Headers
· VBV
· Quantizer
· DCT Coefficients
· Motion vectors ...
But to understand the
compression standard more clearly it is necessary to comprehend the
meaning of these expressions and their position and importance in
a MPEG stream.
The biggest problem is, that these parameters are not visible in the
MPEG video stream and therefore they are very difficult to detect
or to explain. For this reason developing some software which enables
these parameters to be extracted conveniently and displayed in a way
that's clear and easy to understand became the criteria.
The software provides for the invisible nature of the signal parameters
making additions to the original picture with information which ensures
the MPEG system parameters become visible. This software MPEG analyzer
therefore becomes a very useful tool for both - educational and professional
environments alike.
Educational use:
MPEG is no longer a theoretical issue, but a visible compression
standard that is easier to understand. The user gets visual information
about the whole stream, from the header layer down to the macroblock
and block layer. This primary issue of software is an ideal training
tool for those who want to explain and teach MPEG in a very educational
and visible way - needing no special hardware and running on Windows
from either desktop or laptops.
Professional use:
The software can also be used for MPEG investigation during
product development. It is, for example, a very helpful tool for the
evaluation of different MPEG encoders which normally can only be compared
by the resulting picture quality. But an encoder can be optimised
or valued correctly only by analysing its resulting stream in detail.
The program shows, for example, the motion vectors which indicate
the quality of the motion estimation of the encoder, the display of
the different macroblock coding types, their quantizer values, DCT
coefficients and bits per MB display give very important hints about
the bit allocation within an MPEG-Picture. Furthermore, all the information
and flags that are set in the different header can be displayed by
the program (the values and the bit pattern of every parameter).
Therefore it is possible for the user to check if every bit and all
settings of the different header are correct, because these settings
(picture size, VBV Buffer size, frame rate, bitrate,.) are essential
for the correct initialisation of the decoder.
The current version
of Visual Mpeg is completely software based. It's clearly not optimised
for speed but is however arranged in a very functional, educational
and clear manner. Live input streams cannot be analyzed, the MPEG
streams have to be stored in a file.
There are three different versions of the
software available.
1. VISUALmpegES --- Elementary Stream Analyzer
2. VISUALmpegVQA --- Video Quality Analyzer
2. VISUALmpegPRO --- Bundle of VISUALmpegES and VQA