dm642 osd display

Xavier

Genius 3180 points

hi,all:

I work on the dm642 platform, and now i want to write a some string on the video frame,

and my questions how to improve the efficiency of char display?

Can someone give some useful suggestions?

i also see the example of ti:

void OSDUTIL_text(

Uint8 *pFrame, // pointer to the OSD pixel frame

Uint32 pitch, // Line-to-line pitch, expressed in pixels

OSDUTIL_Point* loc, // Location of first character

char *pString, // Pointer to ASCII string to be shown

OSDUTIL_Font *font, // Font to use

Uint8 fgColor, // Foreground color (i.e. on pixel color)

Uint8 bgColor) // Background color (i.e. off pixel color)

{

Uint32 charSize;

Uint32 stringSize;

Uint8 data;

Uint32 i, j, k;

Uint8 *p;

Uint8 pixColor;

char c;

if(font == OSDUTIL_FONT_DEFAULT) {

font = &fontDefault;

}

stringSize = strlen(pString); // see how long the string is

if (stringSize == 0)

return;

charSize = (font->fontWidth + 7) >> 3; // number of bytes per horz scan line

pFrame += (loc->y * pitch) + loc->x; // move to start of string

for (i = 0; i < font->fontHeight; i++) {

p = pFrame;

for (j = 0; j < stringSize; j++) {

c = pString[j];

c = (c < ' ') ? 0 : c - ' ';

for (k = 0; k < font->fontWidth; k++) {

if ((k & 7) == 0)

data = font->fontData[(c * font->fontHeight + i) * charSize + (k >> 3)];

pixColor = (data & 0x80) ? fgColor : bgColor;

if (pixColor != OSDCOLOR_NODRAW) {

*p++ = pixColor;

} else

p+=2; // don't draw these pixels

data <<= 1; // next pixel in current scan line

}

//p+=2; // two more for inter-character spacing

}

pFrame += pitch;