Title :
Architecture of a coprocessor module for image compositing
Author :
Berekovic, Mladen ; Pirsch, Peter
Author_Institution :
Lab. fur Informationstechnol., Hannover Univ., Germany
Abstract :
This paper proposes the architecture of a coprocesssor module for image compositing. The emerging MPEG-4 standard for multimedia applications allows script-based compositing of audiovisual scenes from multiple audio and visual objects. This involves the composition of the output frame by alpha-blending of Video Object Planes (VOPs). A coprocessor architecture is presented, that works in parallel to an MPEG-4 video- and audio-decoder, and performs computation and bandwidth intensive low-level algorithms for image compositing. The processor has on-chip memories that allow preload of data before it is accessed. VHDL implementation and synthesis for a 0.5μ process show an estimate of 100 MHz achievable clock-frequency and 10 k gates for arithmetic and control circuitry which results in roughly 5 mm2 silicon area. Overall performance is sufficient to compose more than 5 full-screen VOPs with a background of size 704×576 each at 30 Hz
Keywords :
coprocessors; decoding; digital signal processing chips; hardware description languages; image processing equipment; multimedia computing; parallel architectures; telecommunication standards; 0.5 mum; 100 MHz; 30 Hz; MPEG-4 video-decoder; Si area; VHDL implementation; Video Object Planes; alpha-blending; arithmetic circuitry; audio-decoder; audiovisual scenes; control circuitry; coprocessor architecture; coprocessor module; emerging MPEG-4 standard; full-screen VOP; image compositing; multimedia applications; multiple audio objects; on-chip memories; output frame; preload; script-based compositing; Arithmetic; Bandwidth; Circuit synthesis; Clocks; Computer architecture; Concurrent computing; Coprocessors; Layout; MPEG 4 Standard; Silicon;
Conference_Titel :
Electronics, Circuits and Systems, 1998 IEEE International Conference on
Conference_Location :
Lisboa
Print_ISBN :
0-7803-5008-1
DOI :
10.1109/ICECS.1998.814863