huffman_tables.v

基于FPGA的JPEG图像压缩芯片设计

    8'h51: jpeg_ac_chrominance_huffman_enc = {4'h5, 16'b0000_0000_0011_1011};
    8'h52: jpeg_ac_chrominance_huffman_enc = {4'h9, 16'b0000_0011_1111_1001};
    8'h53: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1001_1111};
    8'h54: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0000};
    8'h55: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0001};
    8'h56: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0010};
    8'h57: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0011};
    8'h58: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0100};
    8'h59: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0101};
    8'h5a: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0110};

    8'h61: jpeg_ac_chrominance_huffman_enc = {4'h6, 16'b0000_0000_0111_1001};
    8'h62: jpeg_ac_chrominance_huffman_enc = {4'ha, 16'b0000_0111_1111_0111};
    8'h63: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_0111};
    8'h64: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1000};
    8'h65: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1001};
    8'h66: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1010};
    8'h67: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1011};
    8'h68: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1100};
    8'h69: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1101};
    8'h6a: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1110};

    8'h71: jpeg_ac_chrominance_huffman_enc = {4'h6, 16'b0000_0000_0111_1010};
    8'h72: jpeg_ac_chrominance_huffman_enc = {4'ha, 16'b0000_0111_1111_1000};
    8'h73: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1010_1111};
    8'h74: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0000};
    8'h75: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0001};
    8'h76: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0010};
    8'h77: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0011};
    8'h78: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0100};
    8'h79: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0101};
    8'h7a: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0110};

    8'h81: jpeg_ac_chrominance_huffman_enc = {4'h7, 16'b0000_0000_1111_1001};
    8'h82: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_0111};
    8'h83: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1000};
    8'h84: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1001};
    8'h85: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1010};
    8'h86: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1011};
    8'h87: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1100};
    8'h88: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1101};
    8'h89: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1110};
    8'h8a: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1011_1111};

    8'h91: jpeg_ac_chrominance_huffman_enc = {4'h8, 16'b0000_0001_1111_0111};
    8'h92: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0000};
    8'h93: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0001};
    8'h94: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0010};
    8'h95: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0011};
    8'h96: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0100};
    8'h97: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0101};
    8'h98: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0110};
    8'h99: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_0111};
    8'h9a: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1000};

    8'ha1: jpeg_ac_chrominance_huffman_enc = {4'h8, 16'b0000_0001_1111_1000};
    8'ha2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1001};
    8'ha3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1010};
    8'ha4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1011};
    8'ha5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1100};
    8'ha6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1101};
    8'ha7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1110};
    8'ha8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1100_1111};
    8'ha9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0000};
    8'haa: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0001};

    8'hb1: jpeg_ac_chrominance_huffman_enc = {4'h8, 16'b0000_0001_1111_1001};
    8'hb2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0010};
    8'hb3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0011};
    8'hb4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0100};
    8'hb5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0101};
    8'hb6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0110};
    8'hb7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_0111};
    8'hb8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1000};
    8'hb9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1001};
    8'hba: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1010};

    8'hc1: jpeg_ac_chrominance_huffman_enc = {4'h8, 16'b0000_0001_1111_1010};
    8'hc2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1011};
    8'hc3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1100};
    8'hc4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1101};
    8'hc5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1110};
    8'hc6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1101_1111};
    8'hc7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0000};
    8'hc8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0001};
    8'hc9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0010};
    8'hca: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0011};

    8'hd1: jpeg_ac_chrominance_huffman_enc = {4'ha, 16'b0000_0111_1111_1001};
    8'hd2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0100};
    8'hd3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0101};
    8'hd4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0110};
    8'hd5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_0111};
    8'hd6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1000};
    8'hd7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1001};
    8'hd8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1010};
    8'hd9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1011};
    8'hda: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1100};

    8'he1: jpeg_ac_chrominance_huffman_enc = {4'hd, 16'b0011_1111_1110_0000};
    8'he2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1101};
    8'he3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1110};
    8'he4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1110_1111};
    8'he5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0000};
    8'he6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0001};
    8'he7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0010};
    8'he8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0011};
    8'he9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0100};
    8'hea: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0101};

    8'hf0: jpeg_ac_chrominance_huffman_enc = {4'h9, 16'b0000_0011_1111_1010}; // ZRL
    8'hf1: jpeg_ac_chrominance_huffman_enc = {4'he, 16'b0111_1111_1100_0011};
    8'hf2: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0110};
    8'hf3: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_0111};
    8'hf4: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1000};
    8'hf5: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1001};
    8'hf6: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1010};
    8'hf7: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1011};
    8'hf8: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1100};
    8'hf9: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1101};
    8'hfa: jpeg_ac_chrominance_huffman_enc = {4'hf, 16'b1111_1111_1111_1110};
  endcase
end
endfunction // jpeg_ac_chrominance_huffman_enc


/* *********************** */
/* *** D E C O D I N G *** */
/* *********************** */

/*
  J P E G _ D C _ L U M I N A N C E _ H U F F M A N _ D E C

  ITU-T.81 annex K.3.1 Table K.3

  This function translates the default Huffman codeword into the
  luminance DC coefficient difference category.
  Output is given as:
  codelength[3:0]-1, category[3:0]

  The codewords are left-alligned to ease bitstream decomposition.

  example:
  codeword = 9'b1_0011_010
  codelength = 2 +1 = 3
  category = 3
*/
function [7:0] jpeg_dc_luminance_huffman_dec;
  input [8:0] codeword;
begin
  casex(codeword) // synopsys full_case parallel_case
    9'b0_0???_????: jpeg_dc_luminance_huffman_dec = {4'h1, 4'h0};
    9'b0_10??_????: jpeg_dc_luminance_huffman_dec = {4'h2, 4'h1};
    9'b0_11??_????: jpeg_dc_luminance_huffman_dec = {4'h2, 4'h2};
    9'b1_00??_????: jpeg_dc_luminance_huffman_dec = {4'h2, 4'h3};
    9'b1_01??_????: jpeg_dc_luminance_huffman_dec = {4'h2, 4'h4};
    9'b1_10??_????: jpeg_dc_luminance_huffman_dec = {4'h2, 4'h5};
    9'b1_110?_????: jpeg_dc_luminance_huffman_dec = {4'h3, 4'h6};
    9'b1_1110_????: jpeg_dc_luminance_huffman_dec = {4'h4, 4'h7};
    9'b1_1111_0???: jpeg_dc_luminance_huffman_dec = {4'h5, 4'h8};
    9'b1_1111_10??: jpeg_dc_luminance_huffman_dec = {4'h6, 4'h9};
    9'b1_1111_110?: jpeg_dc_luminance_huffman_dec = {4'h7, 4'ha};
    9'b1_1111_1110: jpeg_dc_luminance_huffman_dec = {4'h8, 4'hb};
  endcase
end
endfunction // jpeg_dc_luminance_huffman_dec


/*
  J P E G _ D C _ C H R O M I N A N C E _ H U F F M A N _ D E C

  ITU-T.81 annex K.3.1 Table K.4

  This function translates the default Huffman codeword into
  the chrominance DC coefficient difference.
  Output is given as:
  codelength[3:0]-1, category [3:0]

  The codewords are left-alligned to ease bitstream decomposition.

  example:
  dc_chrominance_coefficient = 3
  codelength = 2 +1 = 3
  codeword   = 11'b0_0000_0110 => 3'b110
*/
function [7:0] jpeg_dc_chrominance_huffman_dec;
  input [10:0] codeword;
begin
  casex(codeword) // synopsys full_case parallel_case
    11'b00?_????_????: jpeg_dc_chrominance_huffman_dec = {4'h1, 4'h0};
    11'b01?_????_????: jpeg_dc_chrominance_huffman_dec = {4'h1, 4'h1};
    11'b10?_????_????: jpeg_dc_chrominance_huffman_dec = {4'h1, 4'h2};
    11'b110_????_????: jpeg_dc_chrominance_huffman_dec = {4'h2, 4'h3};
    11'b111_0???_????: jpeg_dc_chrominance_huffman_dec = {4'h3, 4'h4};
    11'b111_10??_????: jpeg_dc_chrominance_huffman_dec = {4'h4, 4'h5};
    11'b111_110?_????: jpeg_dc_chrominance_huffman_dec = {4'h5, 4'h6};
    11'b111_1110_????: jpeg_dc_chrominance_huffman_dec = {4'h6, 4'h7};
    11'b111_1111_0???: jpeg_dc_chrominance_huffman_dec = {4'h7, 4'h8};
    11'b111_1111_10??: jpeg_dc_chrominance_huffman_dec = {4'h8, 4'h9};
    11'b111_1111_110?: jpeg_dc_chrominance_huffman_dec = {4'h9, 4'ha};
    11'b111_1111_1110: jpeg_dc_chrominance_huffman_dec = {4'ha, 4'hb};
  endcase
end
endfunction // jpeg_dc_chrominance_huffman_dec