URL https://opencores.org/ocsvn/nova/nova/trunk

Subversion Repositories nova

[/] [nova/] [tags/] [Start/] [src/] [level_decoding.v] - Blame information for rev 11

Details | Compare with Previous | View Log


//--------------------------------------------------------------------------------------------------
// Design    : nova
// Author(s) : Ke Xu
// Email           : eexuke@yahoo.com
// File      : level_decoding.v
// Generated : June 9, 2005
// Copyright (C) 2008 Ke Xu                
//-------------------------------------------------------------------------------------------------
// Description 
// Devive the level_prefix,level_suffix,suffixLength,levelSuffixSize,levelCode
// In systemC,levelSuffixSize is decoded @LevelPrefix,in RTL,now changed to @LevelSuffix
// level_suffix[7:0],levelCode[7:0],level[8:0]
// 1. level_abs_tmp[8:0]:|levelCode+2| or |-levelCode-1|                                   | reg
// 2. level_abs    [7:0]:level_abs_tmp >> 1 and latched, used for suffixLength calculation | wire
// 3. level_tmp    [8:0]:2's complement, equals (levelCode+2)>>1 or (-levelCode-1)>>1      | wire
// 4. level_0 ~ level_15:According to i_level,level_tmp is assigned to level_[i_level]     | reg
//    level_0 ~ level_15 are 2's complement
//-------------------------------------------------------------------------------------------------
 
// synopsys translate_off
`include "timescale.v"
// synopsys translate_on
`include "nova_defines.v"
 
module level_decoding (clk,reset_n,cavlc_decoder_state,heading_one_pos,suffix_length_initialized,i_level,
        TotalCoeff,TrailingOnes,BitStream_buffer_output,
        levelSuffixSize,
        level_0,level_1,level_2, level_3, level_4, level_5, level_6, level_7,
        level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15);
        input clk,reset_n;
        input [3:0] cavlc_decoder_state;
        input [3:0] heading_one_pos;
        input suffix_length_initialized;
        input [3:0] i_level;
        input [4:0] TotalCoeff;
        input [1:0] TrailingOnes;
        input [15:0] BitStream_buffer_output;
        output [3:0] levelSuffixSize;
        output [8:0] level_0,level_1,level_2,level_3,level_4,level_5,level_6,level_7;
        output [8:0] level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15;
 
        reg [3:0] levelSuffixSize;
        reg [8:0] level_0,level_1,level_2,level_3,level_4,level_5,level_6,level_7;
        reg [8:0] level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15;
 
        reg [3:0] level_prefix;
        reg [3:0] suffixLength;
        reg [11:0] level_suffix;
        reg [8:0] levelCode;
        reg [8:0] level_tmp;
        reg [7:0] level_abs;
 
        wire [8:0] levelCode_tmp;
 
        //@LevelPrefix,latch the result
        always @ (posedge clk)
                if (reset_n == 0)
                        level_prefix <= 0;
                else if (cavlc_decoder_state == `LevelPrefix)
                        level_prefix <= heading_one_pos;
        //@LevelPrefix,latch the result         
        always @ (posedge clk)
                if (reset_n == 0)
                        suffixLength <= 0;
                else if (cavlc_decoder_state == `LevelPrefix)
                        begin
                                if (suffix_length_initialized == 1'b0)
                                        suffixLength <= (TotalCoeff > 10 && TrailingOnes < 3)? 4'd1:4'd0;
                                //Revise log:March 26,2006
                                //else if (suffixLength == 0 && ((level_abs > (8'd3 << (suffixLength - 1))) && suffixLength < 6))
                                else if (suffixLength == 0 && level_abs > 8'd3)
                                        suffixLength <= 4'd2;
                                else if (suffixLength == 0)
                                        suffixLength <= 4'd1;
                                else if ((level_abs > (8'd3 << (suffixLength - 1))) && suffixLength < 6)
                                        suffixLength <= suffixLength + 1;
                        end
        //@LevelSuffix,temporary result
        always @ (cavlc_decoder_state or level_prefix or suffixLength)
                if (cavlc_decoder_state == `LevelSuffix)
                        begin
                                if (level_prefix == 14 && suffixLength == 0)
                                        levelSuffixSize <= 4;
                                else if (level_prefix == 4'd15)
                                        levelSuffixSize <= 4'd12;
                                else
                                        levelSuffixSize <= suffixLength;
                        end
                else
                        levelSuffixSize <= 0;
        //@LevelSuffix,temporay result
        always  @ (cavlc_decoder_state or levelSuffixSize or BitStream_buffer_output)
                if (cavlc_decoder_state == `LevelSuffix)
                        begin
                                if (levelSuffixSize == 0)
                                        level_suffix <= 0;
                                else
                                        case (levelSuffixSize)
                                                1 :level_suffix <= {11'b0,BitStream_buffer_output[15]};
                                                2 :level_suffix <= {10'b0,BitStream_buffer_output[15:14]};
                                                3 :level_suffix <= {9'b0,BitStream_buffer_output[15:13]};
                                                4 :level_suffix <= {8'b0,BitStream_buffer_output[15:12]};
                                                5 :level_suffix <= {7'b0,BitStream_buffer_output[15:11]};
                                                6 :level_suffix <= {6'b0,BitStream_buffer_output[15:10]};
                                                7 :level_suffix <= {5'b0,BitStream_buffer_output[15:9]};
                                                8 :level_suffix <= {4'b0,BitStream_buffer_output[15:8]};
                                                9 :level_suffix <= {3'b0,BitStream_buffer_output[15:7]};
                                                10:level_suffix <= {2'b0,BitStream_buffer_output[15:6]};
                                                11:level_suffix <= {1'b0,BitStream_buffer_output[15:5]};
                                                12:level_suffix <= BitStream_buffer_output[15:4];
                                                default:level_suffix <= 0;
                                        endcase
                        end
                else
                        level_suffix <= 0;
 
        assign levelCode_tmp = (cavlc_decoder_state == `LevelSuffix)? ((level_prefix << suffixLength) + level_suffix):0;
 
        always @ (cavlc_decoder_state or level_prefix or suffixLength or i_level or TrailingOnes or levelCode_tmp)
                if (cavlc_decoder_state == `LevelSuffix)
                        begin
                                if (level_prefix == 15 && suffixLength == 0 && i_level == {2'b0,TrailingOnes} && TrailingOnes < 3)
                                        levelCode <= levelCode_tmp + 17;
                                else if (level_prefix == 15 && suffixLength == 0)
                                        levelCode <= levelCode_tmp + 15;
                                else if (i_level == {2'b0,TrailingOnes} && TrailingOnes < 3)
                                        levelCode <= levelCode_tmp + 2;
                                else
                                        levelCode <= levelCode_tmp;
                        end
                else
                        levelCode <= 0;
        //We need an additional "level_abs" signal here in order to upgrade suffixLength for next codeword,but for 
        //trailingones,no need to do so since abs(+1/-1) will never greater than (3<<(suffixLength-1)).
 
        //level_abs_tmp:absolute value of level
        reg [8:0] level_abs_tmp;
        always @ (cavlc_decoder_state or levelCode)
           if (cavlc_decoder_state == `LevelSuffix)
                        begin
                                if (levelCode[0] == 1'b0) //even
                                        level_abs_tmp <= levelCode + 2;
                                else
                                        level_abs_tmp <= levelCode + 1;
                        end
                else
                        level_abs_tmp <= 0;
 
        //level_abs:latched absolute value of level,for upgrading of suffixLength
        always @ (posedge clk)
                if (reset_n == 0)
                        level_abs <= 0;
                else if (cavlc_decoder_state == `LevelSuffix)
                        level_abs <= level_abs_tmp[8:1];
 
        always @ (cavlc_decoder_state or levelCode or level_abs_tmp)
                if (cavlc_decoder_state == `LevelSuffix)
                        begin
                                if (levelCode[0] == 1'b0) //even
                                        level_tmp <= {1'b0,level_abs_tmp[8:1]};
                                else
                                        level_tmp <= {1'b1,~levelCode[8:1]};
                        end
                else
                        level_tmp <= 0;
 
        always @ (posedge clk)
                if (reset_n == 0)
                        begin
                                level_0 <= 0;    level_1 <= 0;    level_2 <= 0;    level_3 <= 0;
                                level_4 <= 0;    level_5 <= 0;    level_6 <= 0;    level_7 <= 0;
                                level_8 <= 0;    level_9 <= 0;    level_10<= 0;    level_11<= 0;
                                level_12<= 0;    level_13<= 0;    level_14<= 0;    level_15<= 0;
                        end
                else if (cavlc_decoder_state == `TrailingOnesSignFlag)
                        begin
                                level_0 <= (BitStream_buffer_output[15] == 0)? 9'b000000001:9'b111111111;
                                if (TrailingOnes > 1)
                                        level_1 <= (BitStream_buffer_output[14] == 0)? 9'b000000001:9'b111111111;
                                if (TrailingOnes == 3)
                                        level_2 <= (BitStream_buffer_output[13] == 0)? 9'b000000001:9'b111111111;
                        end
                else if (cavlc_decoder_state == `LevelSuffix)
                        case (i_level)
 
                                1 :level_1 <= level_tmp;
                                2 :level_2 <= level_tmp;
                                3 :level_3 <= level_tmp;
                                4 :level_4 <= level_tmp;
                                5 :level_5 <= level_tmp;
                                6 :level_6 <= level_tmp;
                                7 :level_7 <= level_tmp;
                                8 :level_8 <= level_tmp;
                                9 :level_9 <= level_tmp;
                                10:level_10<= level_tmp;
                                11:level_11<= level_tmp;
                                12:level_12<= level_tmp;
                                13:level_13<= level_tmp;
                                14:level_14<= level_tmp;
                                15:level_15<= level_tmp;
                        endcase
endmodule
 
 
 
 

Browse

Tools

Subversion Repositories nova

[/] [nova/] [tags/] [Start/] [src/] [level_decoding.v] - Blame information for rev 11

Line No.	Rev	Author	Line
1	2	eexuke	`//--------------------------------------------------------------------------------------------------`
2			`// Design : nova`
3			`// Author(s) : Ke Xu`
4			`// Email : eexuke@yahoo.com`
5			`// File : level_decoding.v`
6			`// Generated : June 9, 2005`
7			`// Copyright (C) 2008 Ke Xu`
8			`//-------------------------------------------------------------------------------------------------`
9			`// Description`
10			`// Devive the level_prefix,level_suffix,suffixLength,levelSuffixSize,levelCode`
11			`// In systemC,levelSuffixSize is decoded @LevelPrefix,in RTL,now changed to @LevelSuffix`
12			`// level_suffix[7:0],levelCode[7:0],level[8:0]`
13			`// 1. level_abs_tmp[8:0]:\|levelCode+2\| or \|-levelCode-1\| \| reg`
14			`// 2. level_abs [7:0]:level_abs_tmp >> 1 and latched, used for suffixLength calculation \| wire`
15			`// 3. level_tmp [8:0]:2's complement, equals (levelCode+2)>>1 or (-levelCode-1)>>1 \| wire`
16			`// 4. level_0 ~ level_15:According to i_level,level_tmp is assigned to level_[i_level] \| reg`
17			`// level_0 ~ level_15 are 2's complement`
18			`//-------------------------------------------------------------------------------------------------`
19
20			`// synopsys translate_off`
21			`include "timescale.v"
22			`// synopsys translate_on`
23			`include "nova_defines.v"
24
25			`module level_decoding (clk,reset_n,cavlc_decoder_state,heading_one_pos,suffix_length_initialized,i_level,`
26			`TotalCoeff,TrailingOnes,BitStream_buffer_output,`
27			`levelSuffixSize,`
28			`level_0,level_1,level_2, level_3, level_4, level_5, level_6, level_7,`
29			`level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15);`
30			`input clk,reset_n;`
31			`input [3:0] cavlc_decoder_state;`
32			`input [3:0] heading_one_pos;`
33			`input suffix_length_initialized;`
34			`input [3:0] i_level;`
35			`input [4:0] TotalCoeff;`
36			`input [1:0] TrailingOnes;`
37			`input [15:0] BitStream_buffer_output;`
38			`output [3:0] levelSuffixSize;`
39			`output [8:0] level_0,level_1,level_2,level_3,level_4,level_5,level_6,level_7;`
40			`output [8:0] level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15;`
41
42			`reg [3:0] levelSuffixSize;`
43			`reg [8:0] level_0,level_1,level_2,level_3,level_4,level_5,level_6,level_7;`
44			`reg [8:0] level_8,level_9,level_10,level_11,level_12,level_13,level_14,level_15;`
45
46			`reg [3:0] level_prefix;`
47			`reg [3:0] suffixLength;`
48			`reg [11:0] level_suffix;`
49			`reg [8:0] levelCode;`
50			`reg [8:0] level_tmp;`
51			`reg [7:0] level_abs;`
52
53			`wire [8:0] levelCode_tmp;`
54
55			`//@LevelPrefix,latch the result`
56			`always @ (posedge clk)`
57			`if (reset_n == 0)`
58			`level_prefix <= 0;`
59			else if (cavlc_decoder_state == `LevelPrefix)
60			`level_prefix <= heading_one_pos;`
61			`//@LevelPrefix,latch the result`
62			`always @ (posedge clk)`
63			`if (reset_n == 0)`
64			`suffixLength <= 0;`
65			else if (cavlc_decoder_state == `LevelPrefix)
66			`begin`
67			`if (suffix_length_initialized == 1'b0)`
68			`suffixLength <= (TotalCoeff > 10 && TrailingOnes < 3)? 4'd1:4'd0;`
69			`//Revise log:March 26,2006`
70			`//else if (suffixLength == 0 && ((level_abs > (8'd3 << (suffixLength - 1))) && suffixLength < 6))`
71			`else if (suffixLength == 0 && level_abs > 8'd3)`
72			`suffixLength <= 4'd2;`
73			`else if (suffixLength == 0)`
74			`suffixLength <= 4'd1;`
75			`else if ((level_abs > (8'd3 << (suffixLength - 1))) && suffixLength < 6)`
76			`suffixLength <= suffixLength + 1;`
77			`end`
78			`//@LevelSuffix,temporary result`
79			`always @ (cavlc_decoder_state or level_prefix or suffixLength)`
80			if (cavlc_decoder_state == `LevelSuffix)
81			`begin`
82			`if (level_prefix == 14 && suffixLength == 0)`
83			`levelSuffixSize <= 4;`
84			`else if (level_prefix == 4'd15)`
85			`levelSuffixSize <= 4'd12;`
86			`else`
87			`levelSuffixSize <= suffixLength;`
88			`end`
89			`else`
90			`levelSuffixSize <= 0;`
91			`//@LevelSuffix,temporay result`
92			`always @ (cavlc_decoder_state or levelSuffixSize or BitStream_buffer_output)`
93			if (cavlc_decoder_state == `LevelSuffix)
94			`begin`
95			`if (levelSuffixSize == 0)`
96			`level_suffix <= 0;`
97			`else`
98			`case (levelSuffixSize)`
99			`1 :level_suffix <= {11'b0,BitStream_buffer_output[15]};`
100			`2 :level_suffix <= {10'b0,BitStream_buffer_output[15:14]};`
101			`3 :level_suffix <= {9'b0,BitStream_buffer_output[15:13]};`
102			`4 :level_suffix <= {8'b0,BitStream_buffer_output[15:12]};`
103			`5 :level_suffix <= {7'b0,BitStream_buffer_output[15:11]};`
104			`6 :level_suffix <= {6'b0,BitStream_buffer_output[15:10]};`
105			`7 :level_suffix <= {5'b0,BitStream_buffer_output[15:9]};`
106			`8 :level_suffix <= {4'b0,BitStream_buffer_output[15:8]};`
107			`9 :level_suffix <= {3'b0,BitStream_buffer_output[15:7]};`
108			`10:level_suffix <= {2'b0,BitStream_buffer_output[15:6]};`
109			`11:level_suffix <= {1'b0,BitStream_buffer_output[15:5]};`
110			`12:level_suffix <= BitStream_buffer_output[15:4];`
111			`default:level_suffix <= 0;`
112			`endcase`
113			`end`
114			`else`
115			`level_suffix <= 0;`
116
117			assign levelCode_tmp = (cavlc_decoder_state == `LevelSuffix)? ((level_prefix << suffixLength) + level_suffix):0;
118
119			`always @ (cavlc_decoder_state or level_prefix or suffixLength or i_level or TrailingOnes or levelCode_tmp)`
120			if (cavlc_decoder_state == `LevelSuffix)
121			`begin`
122			`if (level_prefix == 15 && suffixLength == 0 && i_level == {2'b0,TrailingOnes} && TrailingOnes < 3)`
123			`levelCode <= levelCode_tmp + 17;`
124			`else if (level_prefix == 15 && suffixLength == 0)`
125			`levelCode <= levelCode_tmp + 15;`
126			`else if (i_level == {2'b0,TrailingOnes} && TrailingOnes < 3)`
127			`levelCode <= levelCode_tmp + 2;`
128			`else`
129			`levelCode <= levelCode_tmp;`
130			`end`
131			`else`
132			`levelCode <= 0;`
133			`//We need an additional "level_abs" signal here in order to upgrade suffixLength for next codeword,but for`
134			`//trailingones,no need to do so since abs(+1/-1) will never greater than (3<<(suffixLength-1)).`
135
136			`//level_abs_tmp:absolute value of level`
137			`reg [8:0] level_abs_tmp;`
138			`always @ (cavlc_decoder_state or levelCode)`
139			if (cavlc_decoder_state == `LevelSuffix)
140			`begin`
141			`if (levelCode[0] == 1'b0) //even`
142			`level_abs_tmp <= levelCode + 2;`
143			`else`
144			`level_abs_tmp <= levelCode + 1;`
145			`end`
146			`else`
147			`level_abs_tmp <= 0;`
148
149			`//level_abs:latched absolute value of level,for upgrading of suffixLength`
150			`always @ (posedge clk)`
151			`if (reset_n == 0)`
152			`level_abs <= 0;`
153			else if (cavlc_decoder_state == `LevelSuffix)
154			`level_abs <= level_abs_tmp[8:1];`
155
156			`always @ (cavlc_decoder_state or levelCode or level_abs_tmp)`
157			if (cavlc_decoder_state == `LevelSuffix)
158			`begin`
159			`if (levelCode[0] == 1'b0) //even`
160			`level_tmp <= {1'b0,level_abs_tmp[8:1]};`
161			`else`
162			`level_tmp <= {1'b1,~levelCode[8:1]};`
163			`end`
164			`else`
165			`level_tmp <= 0;`
166
167			`always @ (posedge clk)`
168			`if (reset_n == 0)`
169			`begin`
170			`level_0 <= 0; level_1 <= 0; level_2 <= 0; level_3 <= 0;`
171			`level_4 <= 0; level_5 <= 0; level_6 <= 0; level_7 <= 0;`
172			`level_8 <= 0; level_9 <= 0; level_10<= 0; level_11<= 0;`
173			`level_12<= 0; level_13<= 0; level_14<= 0; level_15<= 0;`
174			`end`
175			else if (cavlc_decoder_state == `TrailingOnesSignFlag)
176			`begin`
177			`level_0 <= (BitStream_buffer_output[15] == 0)? 9'b000000001:9'b111111111;`
178			`if (TrailingOnes > 1)`
179			`level_1 <= (BitStream_buffer_output[14] == 0)? 9'b000000001:9'b111111111;`
180			`if (TrailingOnes == 3)`
181			`level_2 <= (BitStream_buffer_output[13] == 0)? 9'b000000001:9'b111111111;`
182			`end`
183			else if (cavlc_decoder_state == `LevelSuffix)
184			`case (i_level)`
185
186			`1 :level_1 <= level_tmp;`
187			`2 :level_2 <= level_tmp;`
188			`3 :level_3 <= level_tmp;`
189			`4 :level_4 <= level_tmp;`
190			`5 :level_5 <= level_tmp;`
191			`6 :level_6 <= level_tmp;`
192			`7 :level_7 <= level_tmp;`
193			`8 :level_8 <= level_tmp;`
194			`9 :level_9 <= level_tmp;`
195			`10:level_10<= level_tmp;`
196			`11:level_11<= level_tmp;`
197			`12:level_12<= level_tmp;`
198			`13:level_13<= level_tmp;`
199			`14:level_14<= level_tmp;`
200			`15:level_15<= level_tmp;`
201			`endcase`
202			`endmodule`
203
204
205
206