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//--------------------------------------------------------------------------------------------------

// Design    : nova

// Author(s) : Ke Xu

// Email           : eexuke@yahoo.com

// File      : dependent_variable_decoding.v

// Generated : June 6,2005

// Copyright (C) 2008 Ke Xu                

//-------------------------------------------------------------------------------------------------

// Description 

// for u(v) decoding as frame_num,pic_order_cnt_lsb

//-------------------------------------------------------------------------------------------------

// synopsys translate_off

`include "timescale.v"

// synopsys translate_on

`include "nova_defines.v"

module dependent_variable_decoding (slice_header_state,log2_max_frame_num_minus4,

        log2_max_pic_order_cnt_lsb_minus4,BitStream_buffer_output,

        dependent_variable_len,dependent_variable_decoding_output);

        input [3:0] slice_header_state;

        input [3:0] log2_max_frame_num_minus4;

        input [3:0] log2_max_pic_order_cnt_lsb_minus4;

        input [15:0] BitStream_buffer_output;

        output [3:0] dependent_variable_len;

        output [9:0] dependent_variable_decoding_output;

        reg [3:0] dependent_variable_len;

        reg [9:0] dependent_variable_decoding_output;

        always @ (slice_header_state or log2_max_frame_num_minus4 or log2_max_pic_order_cnt_lsb_minus4)

                if (slice_header_state == `frame_num_s)

                        dependent_variable_len <= log2_max_frame_num_minus4 + 4;

                else if (slice_header_state == `pic_order_cnt_lsb_s)

                        dependent_variable_len <= log2_max_pic_order_cnt_lsb_minus4 + 4;

                else

                        dependent_variable_len <= 0;

        always @ (slice_header_state or dependent_variable_len or BitStream_buffer_output)

                if (slice_header_state == `frame_num_s || slice_header_state == `pic_order_cnt_lsb_s)

                        case (dependent_variable_len)

                                4 :dependent_variable_decoding_output <= {6'b0,BitStream_buffer_output[15:12]};

                                5 :dependent_variable_decoding_output <= {5'b0,BitStream_buffer_output[15:11]};

                                6 :dependent_variable_decoding_output <= {4'b0,BitStream_buffer_output[15:10]};

                                7 :dependent_variable_decoding_output <= {3'b0,BitStream_buffer_output[15:9]};

                                8 :dependent_variable_decoding_output <= {2'b0,BitStream_buffer_output[15:8]};

                                9 :dependent_variable_decoding_output <= {1'b0,BitStream_buffer_output[15:7]};

                                10:dependent_variable_decoding_output <= BitStream_buffer_output[15:6];

                                default:dependent_variable_decoding_output <= 0;

                        endcase

                else

                        dependent_variable_decoding_output <= 0;

endmodule