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Abstract
The Wide-Band Code Division Multiple Access
(WCDMA) is the technology of the third generation mobile
systems. It has many advantages over the second generation
mobile systems. It has better bandwidth efficiency. In
addition, wide-band services such as videophone and Internet
services are provided including video streaming.
In this thesis we will concentrate on wideband services.
This is done by making a deep study on video codecs in
general and concentrating on H.264 video codec. H.264 video
codec is capable of providing good video quality at
substantially lower bit rates than previous standards without
increasing the complexity of design so much that it would be
impractical or excessively expensive to implement. H.264
also provides enough flexibility to allow the standard to be
applied to a wide variety of applications on a wide variety of
networks and systems.
To do that, H.264 uses some mechanisms that are
specified in the international standards (ITU-T
Recommendation H.264 and ISO/IEC 14496-part 10).
The video frame is divided into some macroblocks and
then motion estimation takes place allowing the residual data
to be transferred to the transformer. The transformer applies
the DCT to the frame then the frame is quantized and entropy
encoded to be ready to be sent to the decoder.
We used H.264 Reference software to implement the
encoder and develop it into a digital signal processor. This
includes the study of Linux OS and the Digital Video
Evaluation Module. International Standards were followed to
insure conformance to the standard specifications.
XII
The H.264 encoder was first implemented on Windows
platform. The initial encoding speed was 1.92 fps and became
17.44 fps after some experiments considering parameter
optimizations. Secondly, the encoder software was
implemented on Linux platform. The encoding speed was
12.77 fps. This is due to the difference between Windows and
Linux and their memory management techniques.
After that, the software was implemented on the ARM
processor and the result was 0.70 fps. The reason for this low
speed is that the ARM processor is not manufactured to
perform DSP functions.