DesignCon 2005 The Trade-Offs of Software Programmability in Video Processors Jonah Probell Sorin Cismas Amit Gulati Steve Leibson

DesignCon 2005 Jonah Probell  Digital video & microprocessor designer  Entrepreneur  Intellectual property developer

DesignCon 2005 struct parameters { slice_type, modes, vectors, coefficients }; loop { parameters = decode_symbols(bitstream); if(slice_type == intra) prediction = intra_pred(mode); else /* slice_type == inter */ predicted = frame_buffer[pred_frame] [row + row_vec][col + col_vec]; residuals = inverse_dct(coefficients); frame_buffer[frame][row][col] = deblock(prediction + residuals); } Software Programmable CPU

DesignCon 2005 Fixed Function State Machine Fixed Function Hardwired symbol decode inverse DCT DMA bitstream coefficients modes / vectors + residuals predicted frame buffer memory deblock filter display

DesignCon 2005 struct parameters { slice_type, modes, vectors, coefficients }; loop { parameters = decode_symbols(bitstream); if(slice_type == intra) prediction = intra_pred(mode); else /* slice_type == inter */ predicted = frame_buffer[pred_frame] [row + row_vec][col + col_vec]; residuals = inverse_dct(coefficients); frame_buffer[frame][row][col] = deblock(prediction + residuals); } Enhanced CPU CPU DMA frame buffer memory inverse DCT deblock filter Acceleratorscoprocessors ISA extensions

DesignCon 2005 Multiprocessor DMA bitstream coefficients modes / vectors + residuals predicted frame buffer memory display communicate(); function(); communicate(); function(); communicate(); function(); communicate(); symbol decode CPU inverse DCT CPU deblock filter CPU

DesignCon 2005 Other Video Tasks  Decompression Symbol decode Prediction DMA Inverse DCT Deblocking filter  Frame scaling  Color space conversion  Stream mixing  Stream synchronization  Overlays  Color correction  Interlacing  Digital audio decode and playback