在学习本节课之前需要一些预备知识：文章Verilog文件操作练习（1）BMP图像色彩替换中简单的介绍了BMP文件的格式，以及在文章图像色彩空间转换中学习RGB和YUV色彩空间的概念，在文章verilog 仿真工程应用-生成coe/mif 文件中学习如何通过文本文件或是二进制文件生成可以存储在RAM/ROM IP核中的coe/mif文件。本节课在使用BMP图像生成coe/mif文件的同时也练习使用了前面学过的Verilog文件操作等函数。结合以上的内容，就可以将一张BMP图像的RGB数据提取出来，经过YUV变换（可选），以相应的格式生成coe/mif文件，最终存储在FPGA的RAM/ROM IP核中，实验结构框图如下所示：
图1 实验结构
1. 从BMP图像中提取RGB纯数据
为了简化实验过程，突出实验目的，这里提供的BMP图像都是默认采用RGB24，并且宽度是4的整数倍（DWORD），不用padding。将RGB纯数据提取出来的Verilog代码如下图所示：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/test.bmp"; localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height //建立了一个1920*1080的装24-bit RGB像素数据的矩阵 reg[23:0]rgb_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0); num = $fscanf(fpre,"%c",fbyte1); num = $fscanf(fpre,"%c",fbyte2); if(j < image_height ) begin if(i < image_width) begin rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end else begin j = j + 1; i = 0; rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end end end $fclose(fpre); $display("\n ============= file closed... ============= ") ; #100; $stop; end endmodule |
2. 调整RGB数据格式
在前面介绍BMP格式的文章中有说过，BMP中像素的排列顺序是从左到右，从下到上的，而大部分图片，视频输出显示的排列顺序一般是从左到右，从上到下的，如下图所示的对比。所以本实验为了适应大部分应用程序还需要调整RGB的数据格式。
图2 左为BMP格式中像素排列的方向，右为大部分图片，视频的像素排列方向
调整上文程序中的1920*1080的装24-bit RGB像素数据的矩阵rgb_byte中的行顺序代码如下：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 |
reg[23:0]rgb_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; integer i; integer j; //这里只列出了颠倒RGB像素数据行顺序的部分代码 initial begin i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) rgb_ordered[j][i] = rgb_byte[image_height -1 - j][i]; end end |
3. 变换RGB数据为YUV数据
文章图像色彩空间转换中详细说明了YUV色彩空间的概念，相比于RGB，YUV的优点是可以向下兼容黑白显示，以及根据人眼的视觉感知，调整图像的构成，使其便于后期压缩传输和还原。由YUV还可以扩展成YCbCr，YCbCr简单来说是在YUV的基础上做了偏移和缩放。RGB的构成是红色，绿色和蓝色分量组合，而YUV的构成是亮度（Y，Luminance）和色度（U和V，chrominance）。U表示蓝色投影，V表示红色投影。当U和V成分不存在时，Y单独可以输出到黑白电视上。
从RGB转换到YUV的公式如下所示，从公式中可以看出U和V成分是相对与Y成分的红，蓝投影（相对与Y来说，U和V不是告诉颜色有多少红/蓝，而是说明它比Y更红/蓝多少）。
- Y = 0.299R + 0.587G + 0.144B
- U = -0.147R – 0.289G + 0.436B = 0.492(B – Y)
- V = 0.615R – 0.515G – 0.100B = 0.877(R – Y)
注意：当RGB 取值范围在 0 — 255 之间时：
- Y 的范围： 0 — 255
- U的范围：-112 — +112
- V的范围：-157 — + 157
因为上述公式在实际转换过程中U，V的结果可能为负数，所以为了避免这种情况，将Y，U，V的范围都保证在[0, 255]内，一般会使用下列公式：
- Y = 0.257R + 0.504G + 0.098B + 16
- Cb = -0.148R – 0.291G + 0.439B + 128
- Cr = 0.439R – 0.368G – 0.071B + 128
YCbCr 与YUV的算法非常类似，这两者也经常会被混淆。 但YCbCr非常适合数值视频的存储（在YUV的基础上只是修改了矩阵的相关系数 + 偏移） 。 YCbCr 是ITU-R BT.601协议的一部分，在8-bit数字视频信号存储时：
- Y 的范围：16 — 235
- Cb（U）的范围：16 — 240
- Cr（V）的范围：16 — 240
在将RGB数据转换成YUV之后，这里同样颠倒了YUV数据的列顺序，实现的Verilog代码如下所示：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/test.bmp"; localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height reg[23:0]yuv_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]yuv_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; real y,Cb,Cr; reg[7:0] y_byte,u_byte,v_byte; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0);//****blue num = $fscanf(fpre,"%c",fbyte1);//greeen num = $fscanf(fpre,"%c",fbyte2);//****red // *************** formula ****************** // Y = 0.257R + 0.504G + 0.098B + 16 // Cb = -0.148R - 0.291G + 0.439B + 128 // Cr = 0.439R - 0.368G - 0.071B + 128 y = 0.257*fbyte2 + 0.504*fbyte1 + 0.098*fbyte0 + 16; Cb = -0.148*fbyte2 - 0.291*fbyte1 + 0.439*fbyte0 + 128; Cr = 0.439*fbyte2 - 0.368*fbyte1 - 0.071*fbyte0 + 128 ; //real number to integer number y_byte = $rtoi( y ) ; u_byte = $rtoi( Cb ) ; v_byte = $rtoi( Cr ) ; if(j < image_height) begin if(i < image_width) begin yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end else begin j = j + 1; i = 0; yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end end end i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) yuv_ordered[j][i] = yuv_byte[image_height -1 - j][i]; end $fclose(fpre); $display("\n ============= file closed... ============= ") ; #100; $stop; end endmodule |
4. RGB/YUV数据生成coe/mif文件
对于在Verilog仿真工程中如何生成coe/mif文件，可以参考文章verilog 仿真工程应用-生成coe/mif 文件。这里在此基础上，将输入的input_data替换成RGB/YUV数据，实现的Verilog代码如下：
YUV数据生成coe文件：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/0207/test4.bmp"; // coe file localparam FILE_COE = "D:/Files_import/2022/0207/coe_test.coe"; localparam INPUT_DATA_RADIX = 16; // 16, 10 , 2 localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer fcoe; integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height reg[23:0]yuv_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]yuv_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; real y,Cb,Cr; reg[7:0] y_byte,u_byte,v_byte; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0);//****blue num = $fscanf(fpre,"%c",fbyte1);//greeen num = $fscanf(fpre,"%c",fbyte2);//****red //=================== formula ====================== // Y = 0.257R + 0.504G + 0.098B + 16 // Cb = -0.148R - 0.291G + 0.439B + 128 // Cr = 0.439R - 0.368G - 0.071B + 128 //================================================== y = 0.257*fbyte2 + 0.504*fbyte1 + 0.098*fbyte0 + 16; Cb = -0.148*fbyte2 - 0.291*fbyte1 + 0.439*fbyte0 + 128; Cr = 0.439*fbyte2 - 0.368*fbyte1 - 0.071*fbyte0 + 128 ; y_byte = $rtoi( y ) ; u_byte = $rtoi( Cb ) ; v_byte = $rtoi( Cr ) ; if(j < image_height) begin if(i < image_width) begin yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end else begin j = j + 1; i = 0; yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end end end i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) yuv_ordered[j][i] = yuv_byte[image_height -1 - j][i]; end $fclose(fpre); $display("\n ============= file closed... ============= ") ; //=============================== write coe file =============================== i = 0; j = 0; fcoe = $fopen(FILE_COE, "w"); if(fcoe == 0) begin $display("$open coe file failed") ; $stop; end $display("\n ============= coe file opened... ============= ") ; // coe file $fwrite(fcoe,"memory_initialization_radix = %0d;\n",INPUT_DATA_RADIX); $fwrite(fcoe,"memory_initialization_vector = "); #10; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) if( INPUT_DATA_RADIX == 16) $fwrite(fcoe,"\n%h", yuv_ordered[j][i]); if( INPUT_DATA_RADIX == 2) $fwrite(fcoe,"\n%b",yuv_ordered[j][i]); if( INPUT_DATA_RADIX == 10) $fwrite(fcoe,"\n%d", yuv_ordered[j][i]); #10; end $fwrite(fcoe,";"); #10; $fclose(fcoe) ; $display("\n ============= coe file closed... ============= ") ; // ===================================================================== #100; $stop; end endmodule |
YUV数据生成mif文件：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/0207/test4.bmp"; localparam INPUT_DATA_RADIX = 16; // 16, 10 , 2 // mif file localparam FILE_MIF = "D:/Files_import/2022/0207/mif_test.mif"; localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer fmif; integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height reg[23:0]rgb_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]rgb_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]yuv_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]yuv_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; real y,Cb,Cr; reg[7:0] y_byte,u_byte,v_byte; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0);//****blue num = $fscanf(fpre,"%c",fbyte1);//greeen num = $fscanf(fpre,"%c",fbyte2);//****red //****************** formula *********************** // Y = 0.257R + 0.504G + 0.098B + 16 // Cb = -0.148R - 0.291G + 0.439B + 128 // Cr = 0.439R - 0.368G - 0.071B + 128 y = 0.257*fbyte2 + 0.504*fbyte1 + 0.098*fbyte0 + 16; Cb = -0.148*fbyte2 - 0.291*fbyte1 + 0.439*fbyte0 + 128; Cr = 0.439*fbyte2 - 0.368*fbyte1 - 0.071*fbyte0 + 128 ; y_byte = $rtoi( y ) ; u_byte = $rtoi( Cb ) ; v_byte = $rtoi( Cr ) ; if(j < image_height) begin if(i < image_width) begin yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end else begin j = j + 1; i = 0; yuv_byte[j][ i ] = {y_byte,u_byte,v_byte}; i = i + 1; end end end i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) yuv_ordered[j][i] = yuv_byte[image_height -1 - j][i]; end $fclose(fpre); $display("\n ============= file closed... ============= ") ; // ===================================================================== // mif file i = 0; j = 0; $display("\n ============= mif file opened... ============= ") ; fmif = $fopen(FILE_MIF, "w"); if(fmif == 0) begin $display("$open mif file failed") ; $stop; end $fwrite(fmif,"WIDTH=%0d;\n",24);//YUV data in 24-bits $fwrite(fmif,"DEPTH=%0d;\n\n",image_height*image_width); $fwrite(fmif,"ADDRESS_RADIX=UNS;\n"); if( INPUT_DATA_RADIX == 16) $fwrite(fmif,"DATA_RADIX=HEX;\n\n"); if( INPUT_DATA_RADIX == 10) $fwrite(fmif,"DATA_RADIX=DEC;\n\n"); if( INPUT_DATA_RADIX == 2) $fwrite(fmif,"DATA_RADIX=BIN;\n\n"); $fwrite(fmif,"CONTENT BEGIN\n"); #10; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) if( INPUT_DATA_RADIX == 16) $fwrite(fmif,"\n%h", yuv_ordered[j][i]); if( INPUT_DATA_RADIX == 2) $fwrite(fmif,"\n%b",yuv_ordered[j][i]); if( INPUT_DATA_RADIX == 10) $fwrite(fmif,"\n%d", yuv_ordered[j][i]); #10; end $fwrite(fmif,"END;\n"); #10; $fclose(fmif) ; $display("\n ============= mif file closed... ============= ") ; // ===================================================================== #100; $stop; end endmodule |
RGB数据生成coe文件：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/0207/test4.bmp"; // coe file localparam FILE_COE = "D:/Files_import/2022/0207/coe_test.coe"; localparam INPUT_DATA_RADIX = 16; // 16, 10 , 2 localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer fcoe; integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height reg[23:0]rgb_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]rgb_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0); num = $fscanf(fpre,"%c",fbyte1); num = $fscanf(fpre,"%c",fbyte2); if(j < image_height ) begin if(i < image_width) begin rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end else begin j = j + 1; i = 0; rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end end end i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) //yuv_ordered[j][i] = yuv_byte[image_height -1 - j][i]; rgb_ordered[j][i] = rgb_byte[image_height -1 - j][i]; end $fclose(fpre); $display("\n ============= file closed... ============= ") ; //=============================== write coe file =============================== i = 0; j = 0; fcoe = $fopen(FILE_COE, "w"); if(fcoe == 0) begin $display("$open coe file failed") ; $stop; end $display("\n ============= coe file opened... ============= ") ; // coe file $fwrite(fcoe,"memory_initialization_radix = %0d;\n",INPUT_DATA_RADIX); $fwrite(fcoe,"memory_initialization_vector = "); #10; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) if( INPUT_DATA_RADIX == 16) $fwrite(fcoe,"\n%h", rgb_ordered[j][i]); if( INPUT_DATA_RADIX == 2) $fwrite(fcoe,"\n%b",rgb_ordered[j][i]); if( INPUT_DATA_RADIX == 10) $fwrite(fcoe,"\n%d", rgb_ordered[j][i]); #10; end $fwrite(fcoe,";"); #10; $fclose(fcoe) ; $display("\n ============= coe file closed... ============= ") ; // ===================================================================== #100; $stop; end endmodule |
RGB数据生成mif文件：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 |
`timescale 1ns / 1ps module bmp_1( ); //original bmp file localparam FILE_TXT = "D:/Files_import/2022/0207/test4.bmp"; localparam INPUT_DATA_RADIX = 16; // 16, 10 , 2 // mif file localparam FILE_MIF = "D:/Files_import/2022/0207/mif_test.mif"; localparam WIDTH_PARAM = 1920; localparam HEIGHT_PARAM = 1080; integer fpre;//file integer fmif; integer ret;//param for $fseek integer num;//param for $fread, $fscanf reg[7:0]fbyte[3:0];//storing $fread reg reg[7:0] fbyte0,fbyte1,fbyte2; integer i = 0;//used for loop param integer j = 0;//used for loop param reg [31:0] image_width;//param for counting image width reg [31:0] image_height;//param for counting image height reg[23:0]rgb_byte [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; reg[23:0]rgb_ordered [HEIGHT_PARAM-1 : 0][WIDTH_PARAM-1 :0]; initial begin fpre = $fopen(FILE_TXT, "rb"); //binary read if(fpre == 0) begin $display("$open file failed") ; $stop; end $display("\n ============= file opened... ============= ") ; ret = $fseek(fpre, 8'h12,0);//read from the start, offset set to image width and height num = $fread(fbyte,fpre,0,4); image_width = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image wdith is %d",image_width); #10; num = $fread(fbyte,fpre,0,4); image_height = {fbyte[3],fbyte[2],fbyte[1],fbyte[0]}; $display ("The image height is %d",image_height); ret = $fseek(fpre, 8'h36,0);//read from the start, offset set to pixel array i = 0; j = 0; while($feof(fpre) != 1) begin num = $fscanf(fpre,"%c",fbyte0); num = $fscanf(fpre,"%c",fbyte1); num = $fscanf(fpre,"%c",fbyte2); if(j < image_height ) begin if(i < image_width) begin rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end else begin j = j + 1; i = 0; rgb_byte[j][ i ] = {fbyte2,fbyte1,fbyte0} i = i + 1; end end end i = 0; j = 0; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) //yuv_ordered[j][i] = yuv_byte[image_height -1 - j][i]; rgb_ordered[j][i] = rgb_byte[image_height -1 - j][i]; end $fclose(fpre); // ===================================================================== // mif file i = 0; j = 0; $display("\n ============= mif file opened... ============= ") ; fmif = $fopen(FILE_MIF, "w"); if(fmif == 0) begin $display("$open mif file failed") ; $stop; end $fwrite(fmif,"WIDTH=%0d;\n",24);//YUV data in 24-bits $fwrite(fmif,"DEPTH=%0d;\n\n",image_height*image_width); $fwrite(fmif,"ADDRESS_RADIX=UNS;\n"); if( INPUT_DATA_RADIX == 16) $fwrite(fmif,"DATA_RADIX=HEX;\n\n"); if( INPUT_DATA_RADIX == 10) $fwrite(fmif,"DATA_RADIX=DEC;\n\n"); if( INPUT_DATA_RADIX == 2) $fwrite(fmif,"DATA_RADIX=BIN;\n\n"); $fwrite(fmif,"CONTENT BEGIN\n"); #10; for(j = 0; j <image_height; j = j + 1) begin for(i = 0; i <image_width; i = i + 1) if( INPUT_DATA_RADIX == 16) $fwrite(fmif,"\n%h", rgb_ordered[j][i]); if( INPUT_DATA_RADIX == 2) $fwrite(fmif,"\n%b",rgb_ordered[j][i]); if( INPUT_DATA_RADIX == 10) $fwrite(fmif,"\n%d", rgb_ordered[j][i]); #10; end $fwrite(fmif,"END;\n"); #10; $fclose(fmif) ; $display("\n ============= mif file closed... ============= ") ; // ===================================================================== #100; $stop; end endmodule |
5.扩展
结合之前学习的HDMI图像显示，参见文章HDMI 图像显示 ，前面RGB数据生成的coe文件可以通过ADV7511图像显示工程在FII-PRX100-D FPGA开发板上跑起来，注意ADV7511图像显示工程中规定了图像的大小是480*270，实例将一张480*270的图像通过本文的RGB转coe文件工程，生成相应的coe文件，原图片和生成相应的coe文件如下：
[content_control]
[/content_control]
最后在屏幕上显示的效果如下：
图3 HDMI显示
从以上可知，使用Vivado仿真中的文件操作函数可以将一张图片转成coe文件，并通过HDMI显示在屏幕上。