YUV420视频上面添加字幕

1、source_code
main.c中实现了函数draw_Font_Func()，这个函数可以直接移植到C程序中使用。
zimo.h里面放的是字模转码后的数据。

2、data_yuv
测试用的yuv420数据(352*288) CIF格式，测试前后的数据。

3、zimo_gr.zip
取字幕的软件

/*
* Copyright(C), 2008-2013, Ubuntu Inc.
* File name:        main.c
* Author:           xubinbin 徐彬彬 (Beijing China)
* Version:          1.0
* Date:             2013.06.09
* Description:      
* Function List:    char *draw_Font_Func(char *ptr_frame,const unsigned char font[],int startx,int starty,int color)
* Email:            xubbwd@gmail.com
*/

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>

#include "zimo.h"
        
#define FRAME_WIDTH             (352)
#define FRAME_HEIGHT            (288)
#define FRAME_SIZE              (FRAME_WIDTH*FRAME_HEIGHT*3/2)
#define IN_FILENAME             "in.raw"
#define OUT_FILENAME            "out.raw"
  
const unsigned char table[] = {

/*--  文字:  陈  --*/
/*--  楷体_GB231212;  此字体下对应的点阵为：宽x高=16x16   --*/
0x00,0x40,0x78,0x40,0x48,0x40,0x57,0xFE,0x50,0x80,0x61,0x20,0x51,0x20,0x4A,0x20,
0x4B,0xFC,0x48,0x20,0x69,0x28,0x51,0x24,0x42,0x22,0x44,0x22,0x40,0xA0,0x40,0x40,
  
/*--  文字:  桂  --*/
/*--  楷体_GB231212;  此字体下对应的点阵为：宽x高=16x16   --*/
0x10,0x20,0x10,0x20,0x11,0xFC,0x10,0x20,0xFC,0x20,0x10,0x20,0x33,0xFE,0x38,0x00,
0x54,0x20,0x54,0x20,0x91,0xFC,0x10,0x20,0x10,0x20,0x10,0x20,0x13,0xFE,0x10,0x00,
  
/*--  文字:  芳  --*/
/*--  楷体_GB231212;  此字体下对应的点阵为：宽x高=16x16   --*/
0x08,0x20,0x08,0x20,0xFF,0xFE,0x08,0x20,0x0A,0x20,0x01,0x00,0xFF,0xFE,0x04,0x00,
0x04,0x00,0x07,0xF0,0x04,0x10,0x08,0x10,0x08,0x10,0x10,0x10,0x20,0xA0,0x40,0x40,

};
  
/*
* Function:     draw_Font_Func
* Description:  实现在yuv420图片上面画字 
* Input:        char *ptr_frame             一帧视频的首地址
*               const unsigned char font[]  画的字模
*               int startx                  写字的起点坐标x
*               int starty                  写字的起点坐标y
*               int color                   字颜色的选择，具体颜色在程序代码
* Return:       这里会把传进来的一帧视频的地址返回，可以不调用  
*/
char *draw_Font_Func(char *ptr_frame,const unsigned char font[],int startx,int starty,int color)
{
  
    assert( ptr_frame != NULL );
  
    int tagY=0,tagU=0,tagV=0;
    char *offsetY=NULL,*offsetU=NULL,*offsetV=NULL;
    unsigned short p16, mask16; // for reading hzk16 dots
      
    /*yuv 地址的设置 */
    offsetY = ptr_frame;
    offsetU = offsetY + FRAME_WIDTH * FRAME_HEIGHT;
    offsetV = offsetU + FRAME_WIDTH * FRAME_HEIGHT/4;
      
    switch (color)
    {
        case 0:         // Yellow
            tagY = 226;tagU = 0;tagV = 149;
            break;
        case 1:         // Red
            tagY = 76;tagU = 85;tagV = 255;
            break;
        case 2:         // Green
            tagY = 150;tagU = 44;tagV = 21;
            break;
        case 3:         // Blue
            tagY = 29;tagU = 255;tagV = 107;
            break;
        default:        // White
            tagY = 128;tagU = 128;tagV = 128;
    }  
      
    int x=0,y=0,i=1,j=0,k=0;
    for(i = 0; i < 3; i++)
    {
    #if 0
        for (j = 0, y = starty; j < 16 && y < FRAME_HEIGHT - 1; j++, y+=2)    // line dots per char
        {
            p16 = *(unsigned short *)(font + j*2 + i*32);/*取字模数据*/
            mask16 = 0x0080;  /* 二进制 1000 0000 */
            for (k = 0, x = startx +i*36; k < 16 && x < FRAME_WIDTH - 1; k++, x+=2)   // dots in a line
            {
                if (p16 & mask16)
                {
                    *(offsetY + y*FRAME_WIDTH + x) = *(offsetY + y*FRAME_WIDTH + x+1) = tagY;
                    *(offsetY + (y+1)*FRAME_WIDTH + x) = *(offsetY + (y+1)*FRAME_WIDTH + x+1) = tagY;   
                    *(offsetU + y * FRAME_WIDTH/4 + x/2) =tagU;
                    *(offsetV + y * FRAME_WIDTH/4 + x/2) = tagV;
                }
                mask16 = mask16 >> 1;  /* 循环移位取数据 */
                if (mask16 == 0)
                    mask16 = 0x8000;
            }
        }
    #else
        for (j = 0, y = starty; j < 16 && y < FRAME_HEIGHT - 1; j++, y++) // line dots per char
        {
            p16 = *(unsigned short *)(font + j*2 + i*32);/*取字模数据*/
            mask16 = 0x0080;  /* 二进制 1000 0000 */
            for (k = 0, x = startx +i*18; k < 16 && x < FRAME_WIDTH - 1; k++, x++) // dots in a line
            {
                if (p16 & mask16)
                {
                    *(offsetY + y*FRAME_WIDTH + x) = 255;
                //  *(offsetU + y * FRAME_WIDTH/4 + x/2) = 85;
                //  *(offsetV + y * FRAME_WIDTH/4 + x/2) = 255;
                }
                mask16 = mask16 >> 1;  /* 循环移位取数据 */
                if (mask16 == 0)
                    mask16 = 0x8000;
            }
        }
    #endif
    }
  
    return (char *)ptr_frame;
}
  
int main(int argc,char * argv[])
{
    int ret = 0;
    FILE *in_file,*out_file;
        
    char *frame_buffer = NULL;
    frame_buffer = (char*)malloc(FRAME_SIZE);
        
    //read frame file 读原来的一帧数据
    in_file = fopen(IN_FILENAME,"r");
    if (in_file == NULL)
    {
        printf("open in file error!\n");
    }

    ret = fread(frame_buffer,FRAME_SIZE,1,in_file);
    if (ret != 1)
    {
        printf("ret = %d\n");
        printf("fread file error!\n");
    }
    fclose(in_file);
  
    //数据转换
    draw_Font_Func(frame_buffer,table,20,10,1);
        
    //write frame file 把数据写回
    out_file = fopen(OUT_FILENAME,"w");
    if (out_file == NULL)
    {
        printf("open in file error!\n");
    }
    
    ret = fwrite(frame_buffer,FRAME_SIZE,1,out_file);
    if (ret != 1)
    {
        printf("ret = %d\n");
        printf("fwrite file error!\n");
    }
    fclose(out_file);
    free(frame_buffer);
  
    printf("Done!\n");
    return 0;
}