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DM36x IPNC OSD显示中文 --- 基本数据准备篇

时间:2017-04-03 16:07:11      阅读:294      评论:0      收藏:0      [点我收藏+]

标签:alt   时间   net   win   ima   ons   网上   render   提示   

经过上一篇的叙述,基本原理搞清楚后,便需要对我们在OSD上显示中文作数据准备,
首先是需要将gb2312关键区(也就是实际有文字存在的区)中的汉字转换为图片,在实际的转换中,并不像上一篇中GB2312编码转换为UNICODE描述一样,
使用libiconv库中的iconv函数将94x94的gb2312编码表直接传递给iconv函数会转换失败(错误提示不完整的多字节字符或宽字符).为了简化这其中的转换难度,目前使用的是查表的方法将GB2312编码转换为UNICODE编码,
这样就要求先准备好GB2312 UNICODE对照表,这个表网上有各种形式的,但是通过我花了很长时间查找也没有找到合适自己需求的,主要是网上的GB2312区位码不全,都会丢掉某些区中的某些编码,这样会有个问题,
就是我们转换后的数据需要记录我们中间丢失了哪些编码,对应的位置等等.会造成后续程序执行效率降低和设计难度加大.这里我是直接将94x94个GB2312编码都转换为对应的unicode编码,保存在一个数组中(很占篇幅,这里不贴实际数据了),通过查找下标的方式查找对应的UNICODE编码.
将对应的GB2312编码转换为UNICODE编码后,接下来就是使用Freetype2将该UNICODE码提取出对应的字符映像,并转换为位图,保存在磁盘上了,下面是其中的核心程序:
//linux下保存24位bmp图像,数据结构FileHead、Infohead见上一篇

 1 int save_bmp24(char * filename,int width,int height,unsigned char *data)
 2 {
 3     FileHead bmp_head;
 4     Infohead bmp_info;
 5     int size = width*height*3;
 6     FILE *fp = fopen(filename,"wb");
 7     if(!fp)
 8     {
 9         perror("open file error");
10         return -1;
11     }
12 
13     bmp_head.bfType=0x4d42;
14     bmp_head.bfSize=size+sizeof(FileHead)+sizeof(Infohead);//24+head+info no quad    
15     bmp_head.bfReserved1=bmp_head.bfReserved2=0;
16     bmp_head.bfOffBits=bmp_head.bfSize-size;
17 
18     bmp_info.biSize=40;
19     bmp_info.biWidth=width;
20     bmp_info.biHeight=-height;//如果为正数,转换出来的图片还需要进行垂直翻转
21     bmp_info.biPlanes=1;
22     bmp_info.biBitCount = 24;
23     bmp_info.biCompress=0;
24     bmp_info.biSizeImage=size;
25     bmp_info.biXPelsPerMeter=0;
26     bmp_info.biYPelsPerMeter=0;
27     bmp_info.biClrUsed=0;
28     bmp_info.biClrImportant=0;
29 
30     fwrite(&bmp_head,1,sizeof(FileHead),fp);
31     fwrite(&bmp_info,1,sizeof(Infohead),fp);
32     fwrite(data,1,size,fp);
33     fclose(fp);
34     return 0;
35 }

//转换函数,这里是一个区转换为一个图片

  1 int convert(const char * font_file,int font_width,int font_height)
  2 {
  3     FT_Library library = NULL;
  4     FT_Face face = NULL;
  5     int error;
  6     int char_index;
  7     int char_code;
  8     
  9     unsigned char * bmpdata = NULL,*pdata;//保存一个字的图片数据
 10     int isVert = 0;//是否垂直布局,中文为垂直布局
 11     FT_Bitmap *ft_bmp;
 12     
 13     unsigned short  unicode;//用于存储unicode
 14     int index=0;
 15     int area,location;
 16     char testfilename[100];
 17     
 18     unsigned char *image = NULL, *pimage;//一个区转换为一张图片
 19     int temp;
 20     
 21     if(font_width <= 0 && font_height <= 0)
 22     {
 23         printf("invalidate font size.\n");
 24         return -1;
 25     }
 26     if(font_width <= 0)
 27         font_width = font_height;
 28     if(font_height <= 0)
 29         font_height = font_width;
 30     if(font_width % 2)//4字节对齐,这里先保证宽度为4pixel对齐
 31     {
 32         printf("invalidate font size.\n");
 33         return -1;
 34     }
 35     setlocale(LC_ALL,"zh_CN.UTF-8");
 36 
 37     do
 38     {
 39         //下面开始初始化FT2库
 40         error = FT_Init_FreeType(&library);
 41         if (error)
 42         {
 43             printf("can not init free type library!\n");
 44             break;
 45         }
 46 
 47         error = FT_New_Face(library, font_file, 0, &face);
 48         if (error)
 49         {
 50             printf("create new face falied!\n");
 51             break;
 52         }
 53         isVert = FT_HAS_VERTICAL(face);    
 54         error = FT_Set_Pixel_Sizes(face, font_width, font_height);//设置字体大小
 55         if (error)
 56         {
 57             printf("set font size error!\n");
 58             break;
 59         }
 60         bmpdata = malloc(font_width * font_height * 3);
 61         if(!bmpdata)
 62         {
 63             printf("outof memory.\n");
 64             break;
 65         }
 66         image = malloc(94 * font_width * font_height * 3);//这里要求font_size必须为偶数
 67         if(!image)
 68         {
 69             printf("outof memory.\n");
 70             break;
 71         }
 72 
 73 #if 0
 74         //打印字体相关信息
 75         printf("file has %d faces\n", face->num_faces);
 76         printf("%s  italic or oblique,%s bold\n", face->style_flags & FT_STYLE_FLAG_ITALIC ?"support":"not support",face->style_flags & FT_STYLE_FLAG_BOLD ?"support":"not support");
 77         printf("file family name %s\n", face->family_name);
 78         printf("file style name %s\n", face->style_name);
 79         printf("face index %d\n", face->face_index);
 80         printf("number of char %d\n", face->num_glyphs);
 81         printf("number of fixed bitmap %d\n", face->num_fixed_sizes);
 82         printf("Char size %d\n", face->size);
 83         printf("has %d fixed sizes\n",face->num_fixed_sizes);
 84         for(i=0;i<face->num_fixed_sizes;i++)
 85         {
 86             printf("supported size %d:width=%d,heigh=%d\n",i+1,face->available_sizes[i].width,face->available_sizes[i].height);
 87         }
 88 #endif
 89         error = FT_Select_Charmap(face,FT_ENCODING_UNICODE);//这里使用UNICODE映射表,便于使用UNICODE码(char code)来获取char index
 90         if(error)
 91         {
 92             printf("select char map error.\n");
 93             break;
 94         }
 95         //printf("code %x\n",face ->charmap ->encoding);
 96         switch(face ->charmap ->encoding)
 97         {
 98             case FT_ENCODING_MS_GB2312:    printf("USE GB2312 CODE\n");break;
 99             case FT_ENCODING_MS_BIG5:    printf("USE BIG5 CODE\n");break;
100             case FT_ENCODING_UNICODE:    printf("USE UNICODE CODE\n");break;
101             default:
102                 printf("UNKNOWN CODE\n");
103                 goto done;
104                 break;
105         }
106         
107         //实际有字体的区码为(0-8) (15-86)区(区号从0开始 ) = 9 + 72 = 81个区
108         for(area = 0;area < 87;area ++)//1- 87区
109         {
110             if( (area >8 && area < 15)/* 8 - 15区跳过*/
111                 ||(area > 86 && area < 94)/* 87 - 94 区跳过*/
112             )
113             {
114                 continue;
115             }
116             memset(image,0,94 * font_width * font_height * 3);
117             pimage = image;
118             for(location = 0;location < 94;location++)//1 - 94位
119             {
120                 index = area * 94 + location;
121                 if(Gb2312ToUnicode(gb2312_table[index],&unicode) < 0)
122                 {
123                     printf("get unicode code error.gb2312 code 0x%04X\n",gb2312_table[index]);
124                     continue;
125                 }
126                 char_code = unicode;
127                 if(!char_code)
128                 {
129                     printf("\ninvalidate char code.\n");
130                     continue;
131                 }
132                 char_index = FT_Get_Char_Index(face,char_code);
133                 error = FT_Load_Glyph(face, char_index,  FT_LOAD_DEFAULT | FT_LOAD_MONOCHROME);
134                 if (error)
135                 {
136                     printf("\nload char error!\n");
137                     goto done;
138                 }
139                 if (face->glyph->format != FT_GLYPH_FORMAT_BITMAP)
140                 {
141                     error = FT_Render_Glyph(face->glyph, FT_RENDER_MODE_MONO);
142                     if (error)
143                     {
144                         printf("\nrender char failed!\n");
145                         goto done;
146                     }
147                 }
148 
149                 /*
150                 单色位图图像数据的表示方法:
151                 在单色位图图像中,只有两种颜色,黑色或白色,每一个像素只需要一个比特就能够完成表示,为了清楚比特0或1具体表示哪一种颜色,可以通过查询调色板。
152                 在单色位图图像中,调色板只包含两种颜色,每一种颜色用R G B 0 四个字节表示 (在实际的字节流中,顺序是 B G R 0)
153                 所以,位图图像数据中的0 代表调色板中 第一种颜色的颜色值, 1 代表调色板中 第二种颜色的颜色值。
154                 一行单色位图数据的存储格式规定:
155                 每一扫描行的字节数必需是4的整倍数,当不够4的整数倍时,需要加0补齐
156                 以 720 × 450 的单色位图图像为例
157                 水平扫描行的长度为720,则需要720比特来表示一个扫描行,即需要 720/8=90字节来表示,但是 90不是 4 的整数倍,因此需要用0补齐,直至为4的整数倍,即需要额外的2个填充字节。
158                 最终,长度为720的水平扫描行使用了 92 个字节来表示。
159                 NOTE:非8位位图可用函数FT_Bitmap_Convert进行转换
160                 */
161                 //转换为4字节对齐
162                 ft_bmp = &face->glyph->bitmap;
163 #if 0
164                 //dump位图信息
165                 printf("bit_map_left %d bit_map_top %d\n", face->glyph->bitmap_left,face->glyph->bitmap_top);
166                 printf("int rows:%d\n",ft_bmp ->rows);
167                 printf("int width:%d\n",ft_bmp ->width);
168                 printf("int pitch:%d\n",ft_bmp ->pitch);
169                 printf("short num_grays:%d\n",ft_bmp ->num_grays);
170                 printf("char pixel_mode:%d\n",ft_bmp ->pixel_mode);
171                 if(isVert)
172                 {
173                     printf("VERT:(w:%ld h:%ld)(bearingX:%ld bearingY:%ld Advance:%ld)\n",face->glyph->metrics.width/64,face->glyph->metrics.height/64,
174                         face->glyph->metrics.vertBearingX/64,face->glyph->metrics.vertBearingY/64,face->glyph->metrics.horiAdvance/64);
175                 }
176                 else
177                 {
178                     printf("HORI:(w:%ld h:%ld)(bearingX:%ld bearingY:%ld Advance:%ld)\n",face->glyph->metrics.width/64,face->glyph->metrics.height/64,
179                         face->glyph->metrics.horiBearingX/64,face->glyph->metrics.horiBearingY/64,face->glyph->metrics.vertAdvance/64);
180                 }
181                 printf("xMin=%ld, yMin=%ld, xMax=%ld, yMax=%ld\n",face ->bbox.xMin,face ->bbox.yMin,face ->bbox.xMax,face ->bbox.yMax);
182 #endif        
183 
184                 switch(ft_bmp ->pixel_mode)
185                 {
186                     case FT_PIXEL_MODE_MONO://单色位图
187                         {
188                             //将数据转换到24位
189                             int topblank     = 0;//字型顶部距离位图顶部空行数目
190                             int leftblank     = 0;//字型左边距离位图左边空列数目
191                             int rightblank     = 0;//字型右边距离位图右边空列数目
192                             int pitch     = 0;//每个扫描行占用几个字节
193                             int width    = ft_bmp ->width;//实际字型宽度
194                             int height    = ft_bmp ->rows; //实际字型高度
195                             unsigned char * ft_bmp_buff = ft_bmp ->buffer;
196                             int i,j,k;
197                             if(isVert)
198                             {
199                                 topblank     = face->glyph->metrics.vertBearingY/64;
200                                 leftblank     = font_width/2 + face->glyph->metrics.vertBearingX/64;
201                             }
202                             else
203                             {
204                                 topblank    = font_height * 2 /3 - face->glyph->metrics.horiBearingY/64;
205                                 leftblank     = face->glyph->metrics.horiBearingX/64;
206                             }
207                             if(topblank < 0)topblank     = 0;
208                             if(leftblank < 0)leftblank     = 0;
209                             rightblank = font_width - width - leftblank;
210                             if(rightblank < 0)rightblank    = 0;
211                             pitch =  ft_bmp ->width / 8;
212                             if(pitch% ft_bmp ->pitch)
213                                 pitch = pitch + (ft_bmp ->pitch - pitch %ft_bmp ->pitch);
214                             //printf("PITCH=%d\n",pitch);
215                 
216                             //转换1bit位图数据到24bit位图数据
217                             printf("begin convert.area %d ----> %d\r",area,location);
218                             memset(bmpdata,0,font_width * font_height * 3);
219                             pdata = bmpdata;
220                             pdata += topblank *font_width * 3;//跳过上边距
221                             for(i=0;i<height;i++)
222                             {
223                                 pdata += leftblank * 3;
224                                 k = 7;
225                                 for(j=0;j<width;j++)
226                                 {
227                                     if(ft_bmp_buff[j/8] & (1 << k) )
228                                     {
229                                         //pdata[0] = 255;//
230                                         pdata[1] = 255;//绿
231                                         pdata[2] = 255;//
232                                     }
233                                     k--;
234                                     if(k<0)k=7;
235                                     pdata += 3;
236                                 }
237                                 ft_bmp_buff += pitch;
238                                 pdata += rightblank * 3;
239                             }
240                             /*if(!(font_width %4))
241                             {
242                                 sprintf(testfilename,"./testbmp/%d_%d.bmp",area,location );
243                                 printf("\nsave bmp file [%s]\n",testfilename);
244                                 if(save_bmp24(testfilename,font_width ,font_height,bmpdata))
245                                 {
246                                     printf("save bmp file [%s] error.\n",testfilename);
247                                 }
248                             }*/
249     
250                         }
251                         break;
252                     default:
253                         printf("位图为非单色图片.\n");
254                         goto done;
255                         break;
256                 }//switch
257                 pdata = bmpdata;
258                 pimage = image + location * font_width * 3;                
259                 for(temp=0;temp<font_height;temp++)
260                 {
261                     memcpy(pimage,pdata,font_width * 3);
262                     pdata += font_width * 3;
263                     pimage += 94 * font_width *3;
264                 }
265 #ifndef _WIN32
266                 usleep(10);
267 #else
268                 Sleep(10);
269 #endif
270             }//for( 1 - 94 位 )
271             //保存图片
272             sprintf(testfilename,"./testbmp/area%d_%dx%d.bmp",area,font_width,font_height);
273             //printf("\nsave bmp file [%s]\n",testfilename);
274             if(save_bmp24(testfilename,94 * font_width,font_height,image))
275             {
276                 printf("save bmp file [%s] error.\n",testfilename);
277             }
278         }//for( 1 - 94 区)
279         printf("\nConvert Done.\n");
280 
281     }while (0);
282 done:
283 #if 0    //出现莫名其妙的错误,注释了
284     fprintf(stderr,"begin cleanup.\n");
285     if(bmpdata)
286     {
287         free(bmpdata);
288         bmpdata = NULL;
289     }
290     if(image)
291     {
292         free(image);
293         image = NULL;
294     }
295     if(face)
296     {
297         FT_Done_Face(face);
298         face = NULL;
299     }
300     if(library)
301     {
302         FT_Done_FreeType(library);
303         library = NULL;
304     }
305 #endif
306     return 0;
307 }

这里上传几个程序转换的图片:

14x16:

技术分享

16x18:

技术分享
20x24:
技术分享
28x32:
技术分享
将编码转换为图片后,需要将bmp24图片数据转换为yuv420p数据,利用libswscale库进行转换的核心代码已经在上一篇贴了,这里不再重贴.
下面是转换后的结果,当然也可以直接将数据保存为一个二进制文件,而不是一个C源程序文件

 1 /*********************Y***************************/
 2 unsigned char data_Y[]={
 3      0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
 4     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
 5     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
 6     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
 7     ......
 8     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
 9     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
10     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
11     ,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10
12 };
13 //37224 bytes
14 /**************end of Y***************************/
15 
16 /********************UV***************************/
17 unsigned char data_UV[]={
18      0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
19     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
20     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
21     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
22     ......
23     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
24     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80
25     ,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x12,0x92,0x80,0x80,0x80,0x80
26     ,0x80,0x80,0x80,0x80
27 };
28 //18612 bytes
29 /*************end of UV***************************/

http://blog.csdn.net/sloan6/article/details/9231373

DM36x IPNC OSD显示中文 --- 基本数据准备篇

标签:alt   时间   net   win   ima   ons   网上   render   提示   

原文地址:http://www.cnblogs.com/eustoma/p/6662101.html

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