Multimedia coding and streaming Virtual Lab
Under "Multimedia coding and streaming" Virtual Lab, interactive exercises through Graphical User Interfaces (GUIs) are implemented, through which the students are able to study the following topics:
- Audio, Image and Video coding
- Download the Matlab software and documentation here (16MB, .rar)
- Download only the Matlab software here (7MB, .rar)
- Audio and Video transmission through noisy channels
- Download the Matlab software and documentation here (13MB, .rar)
- Download only the Matlab software here (9MB, .rar)
You can also download:
- Some audio files, necessary for the proposed VLAb exercises, here (9MBs .rar) .
- Some avi and cif video files, necessary for the proposed VLAb exercises, here (225MBs .rar).
Audio, Image and Video coding
The students can interact with the following concepts.
Transform coding - Quantization - Entropy coding
With the use of three appropriate GUIs the student can study the main ideas in:
- Transform coding, i.e. coding in transform domain, in which the energy tends to be concentrated in a few significant coefficients.
- Quantization, which is the essential part of “lossy” encoders.
- Entropy coding, which is the last subsystem of modern codecs, which does not introduce information loss (lossless).
- Download the corresponding Matlab GUIs here (0.5MB, *.rar).
Audio coding MPEG - Layer III (MP3)
The students can study the compression standard MP3 (MPEG Audio Layer III).
Attention is paid mainly on the psychoacoustic analysis, based on the limitations of the human hearing system.
- Download the corresponding Matlab GUIs here (0.8MB, *.rar).
Still image compression
With the use of two Matlab GUIs one can study two still image compression standards:
- JPEG (Baseline mode). Empasis is given on the 2-D Discrete Cosine Transform (DCT).
JPEG-2000. Empasis is given on the 2-D Discrete Wavelet Transform (DWT).
- Download the Matlab GUI here (0.2MB, .rar)
- Download the Matlab GUI here (0.3MB, .rar)
MPEG-1,2 Video compression
With the use of three Matlab GUIs one can study the basic ideas in MPEG-1 and MPEG-2.
Attention is paid in:
- Motion estimation and motion compensated prediction.
- The notion of I, P and B frames coding.
- Download the corresponding Matlab GUIs here (3.2MB, *.rar).
MPEG-4, Motion Segmentation
The students can study the idea of motion segmentation, i.e. the separation of moving objects in a video sequence. The encoding of shape and motion of the moving objects is one of the basic ideas in MPEG-4.
- Download the corresponding Matlab GUI here (1.2MB, *.rar).
Video and Audio streaming
Here, the students can study the transmission of digital video and audio through communication channels that are susceptible to noise and packet losses.
Digital Video Broadcasting - Terrestrial (DVB-T) and Video "Error Concelament"
With the use of two Matlab GUIs and Simulink models the user can study:
- The impact of transmission errors on the quality of the recieved and decoded video signal.
- Channel Encoding in DVB-T, i.e. Forward Error Correction / Detection techniques.
- The notion of "Error Concealement" at the decoder.
- Download the corresponding Matlab GUIs here (8MB, *.rar).
Audio streaming VoIP - internet Low Bit-rate Codec (iLBC)
Using an appropriate Matlab GUI and a Simulink model, the user can study the:
- The iLBC codec
- The impact of packet loses errors on the quality of the decoded audio signal
- "Packet Loss Concealment" in iLBC.
- Download the corresponding Matlab GUIs here (0.4MB, *.rar).