[Ffmpeg-devel] [PATCH] drawtext.c: 05 rewrite draw_box using memset()

[Måns Rullgård]

"Gustavo Sverzut Barbieri" <barbieri at gmail.com> writes:

> As suggested here before, rewrite draw_box() using memset(), which
> should be faster.
>
> --- drawtext.c-after_patch04	2006-09-10 14:40:02.000000000 -0300
> +++ drawtext.c	2006-09-10 14:40:47.000000000 -0300
> @@ -368,14 +368,28 @@
>  
>  static inline void draw_box(AVPicture *picture, unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned char yuv_color[3])
>  {
> -  int i, j;
> +  unsigned j, top[3], hx, hy, hwidth, hheight;
>  
> -  for (j = 0; (j < height); j++)
> -    for (i = 0; (i < width); i++)
> -      {
> -        SET_PIXEL(picture, yuv_color, (i+x), (y+j));
> -      }
> +  hx = x >> 1;
> +  hy = y >> 1;
> +  hwidth = width >> 1;
> +  hheight = height >> 1;
>  
> +  top[0] = picture->linesize[0] * y + x;
> +  top[1] = picture->linesize[1] * hy + hx;
> +  top[2] = picture->linesize[2] * hy + hx;
> +
> +  for (j = 0; j < hheight; j++)
> +    {
> +      memset(picture->data[0] + top[0], yuv_color[0], width);
> +      top[0] += picture->linesize[0];
> +
> +      memset(picture->data[0] + top[0], yuv_color[0], width);
> +      top[0] += picture->linesize[0];
> +
> +      memset(picture->data[1] + top[1], yuv_color[1], hwidth);
> +      top[1] += picture->linesize[1];
> +    }
>  }

I think you may have made a copy and paste mistake here.  Did you
really mean to set data[0] twice and data[2] not at all?

-- 
M?ns Rullg?rd
mru at inprovide.com