blend.c

video linux conference

    }

#undef MAX_TRANS
#undef TRANS_BITS

    return;
}

static inline void yuv_to_rgb( int *r, int *g, int *b,
                               uint8_t y1, uint8_t u1, uint8_t v1 )
{
    /* macros used for YUV pixel conversions */
#   define SCALEBITS 10
#   define ONE_HALF  (1 << (SCALEBITS - 1))
#   define FIX(x)    ((int) ((x) * (1<<SCALEBITS) + 0.5))
#   define CLAMP( x ) (((x) > 255) ? 255 : ((x) < 0) ? 0 : (x));

    int y, cb, cr, r_add, g_add, b_add;

    cb = u1 - 128;
    cr = v1 - 128;
    r_add = FIX(1.40200*255.0/224.0) * cr + ONE_HALF;
    g_add = - FIX(0.34414*255.0/224.0) * cb
            - FIX(0.71414*255.0/224.0) * cr + ONE_HALF;
    b_add = FIX(1.77200*255.0/224.0) * cb + ONE_HALF;
    y = (y1 - 16) * FIX(255.0/219.0);
    *r = CLAMP((y + r_add) >> SCALEBITS);
    *g = CLAMP((y + g_add) >> SCALEBITS);
    *b = CLAMP((y + b_add) >> SCALEBITS);
}

static void BlendR16( filter_t *p_filter, picture_t *p_dst_pic,
                      picture_t *p_dst_orig, picture_t *p_src,
                      int i_x_offset, int i_y_offset,
                      int i_width, int i_height, int i_alpha )
{
    int i_src1_pitch, i_src2_pitch, i_dst_pitch;
    uint8_t *p_dst, *p_src1, *p_src2_y;
    uint8_t *p_src2_u, *p_src2_v;
    uint8_t *p_trans;
    int i_x, i_y, i_pix_pitch;
    int r, g, b;

    i_pix_pitch = p_dst_pic->p->i_pixel_pitch;
    i_dst_pitch = p_dst_pic->p->i_pitch;
    p_dst = p_dst_pic->p->p_pixels + i_x_offset * i_pix_pitch +
            p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
            p_dst_pic->p->i_pitch *
            ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src1_pitch = p_dst_orig->p[Y_PLANE].i_pitch;
    p_src1 = p_dst_orig->p->p_pixels + i_x_offset * i_pix_pitch +
               p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
               p_dst_orig->p->i_pitch *
               ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src2_pitch = p_src->p[Y_PLANE].i_pitch;
    p_src2_y = p_src->p[Y_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset +
               p_src->p[Y_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;
    p_src2_u = p_src->p[U_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[U_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;
    p_src2_v = p_src->p[V_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[V_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;

    p_trans = p_src->p[A_PLANE].p_pixels +
              p_filter->fmt_in.video.i_x_offset +
              p_src->p[A_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;

#define MAX_TRANS 255
#define TRANS_BITS  8

    /* Draw until we reach the bottom of the subtitle */
    for( i_y = 0; i_y < i_height; i_y++, p_trans += i_src2_pitch,
         p_dst += i_dst_pitch, p_src1 += i_src1_pitch,
         p_src2_y += i_src2_pitch, p_src2_u += i_src2_pitch,
         p_src2_v += i_src2_pitch )
    {
        /* Draw until we reach the end of the line */
        for( i_x = 0; i_x < i_width; i_x++ )
        {
            if( !p_trans[i_x] )
            {
                /* Completely transparent. Don't change pixel */
                continue;
            }
            else if( p_trans[i_x] == MAX_TRANS )
            {
                /* Completely opaque. Completely overwrite underlying pixel */
                yuv_to_rgb( &r, &g, &b,
                            p_src2_y[i_x], p_src2_u[i_x], p_src2_v[i_x] );

    ((uint16_t *)(&p_dst[i_x * i_pix_pitch]))[0] = ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3);
                continue;
            }

            /* Blending */
            yuv_to_rgb( &r, &g, &b,
                        p_src2_y[i_x], p_src2_u[i_x], p_src2_v[i_x] );

    ((uint16_t *)(&p_dst[i_x * i_pix_pitch]))[0] = ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3);
        }
    }

#undef MAX_TRANS
#undef TRANS_BITS

    return;
}

static void BlendR24( filter_t *p_filter, picture_t *p_dst_pic,
                      picture_t *p_dst_orig, picture_t *p_src,
                      int i_x_offset, int i_y_offset,
                      int i_width, int i_height, int i_alpha )
{
    int i_src1_pitch, i_src2_pitch, i_dst_pitch;
    uint8_t *p_dst, *p_src1, *p_src2_y;
    uint8_t *p_src2_u, *p_src2_v;
    uint8_t *p_trans;
    int i_x, i_y, i_pix_pitch, i_trans;
    int r, g, b;

    i_pix_pitch = p_dst_pic->p->i_pixel_pitch;
    i_dst_pitch = p_dst_pic->p->i_pitch;
    p_dst = p_dst_pic->p->p_pixels + i_x_offset * i_pix_pitch +
            p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
            p_dst_pic->p->i_pitch *
            ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src1_pitch = p_dst_orig->p[Y_PLANE].i_pitch;
    p_src1 = p_dst_orig->p->p_pixels + i_x_offset * i_pix_pitch +
               p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
               p_dst_orig->p->i_pitch *
               ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src2_pitch = p_src->p[Y_PLANE].i_pitch;
    p_src2_y = p_src->p[Y_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset +
               p_src->p[Y_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;
    p_src2_u = p_src->p[U_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[U_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;
    p_src2_v = p_src->p[V_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[V_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;

    p_trans = p_src->p[A_PLANE].p_pixels +
              p_filter->fmt_in.video.i_x_offset +
              p_src->p[A_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;

#define MAX_TRANS 255
#define TRANS_BITS  8

    /* Draw until we reach the bottom of the subtitle */
    for( i_y = 0; i_y < i_height; i_y++, p_trans += i_src2_pitch,
         p_dst += i_dst_pitch, p_src1 += i_src1_pitch,
         p_src2_y += i_src2_pitch, p_src2_u += i_src2_pitch,
         p_src2_v += i_src2_pitch )
    {
        /* Draw until we reach the end of the line */
        for( i_x = 0; i_x < i_width; i_x++ )
        {
            i_trans = ( p_trans[i_x] * i_alpha ) / 255;
            if( !i_trans )
            {
                /* Completely transparent. Don't change pixel */
                continue;
            }
            else if( i_trans == MAX_TRANS )
            {
                /* Completely opaque. Completely overwrite underlying pixel */
                yuv_to_rgb( &r, &g, &b,
                            p_src2_y[i_x], p_src2_u[i_x], p_src2_v[i_x] );

                p_dst[i_x * i_pix_pitch]     = r;
                p_dst[i_x * i_pix_pitch + 1] = g;
                p_dst[i_x * i_pix_pitch + 2] = b;
                continue;
            }

            /* Blending */
            yuv_to_rgb( &r, &g, &b,
                        p_src2_y[i_x], p_src2_u[i_x], p_src2_v[i_x] );

            p_dst[i_x * i_pix_pitch]     = ( r * i_trans +
                (uint16_t)p_src1[i_x * i_pix_pitch] *
                (MAX_TRANS - i_trans) ) >> TRANS_BITS;
            p_dst[i_x * i_pix_pitch + 1] = ( g * i_trans +
                (uint16_t)p_src1[i_x * i_pix_pitch + 1] *
                (MAX_TRANS - i_trans) ) >> TRANS_BITS;
            p_dst[i_x * i_pix_pitch + 2] = ( b * i_trans +
                (uint16_t)p_src1[i_x * i_pix_pitch + 2] *
                (MAX_TRANS - i_trans) ) >> TRANS_BITS;
        }
    }

#undef MAX_TRANS
#undef TRANS_BITS

    return;
}

static void BlendYUY2( filter_t *p_filter, picture_t *p_dst_pic,
                       picture_t *p_dst_orig, picture_t *p_src,
                       int i_x_offset, int i_y_offset,
                       int i_width, int i_height, int i_alpha )
{
    int i_src1_pitch, i_src2_pitch, i_dst_pitch;
    uint8_t *p_dst, *p_src1, *p_src2_y;
    uint8_t *p_src2_u, *p_src2_v;
    uint8_t *p_trans;
    int i_x, i_y, i_pix_pitch, i_trans;
    vlc_bool_t b_even = !((i_x_offset + p_filter->fmt_out.video.i_x_offset)%2);

    i_pix_pitch = 2;
    i_dst_pitch = p_dst_pic->p->i_pitch;
    p_dst = p_dst_pic->p->p_pixels + i_x_offset * i_pix_pitch +
            p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
            p_dst_pic->p->i_pitch *
            ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src1_pitch = p_dst_orig->p[Y_PLANE].i_pitch;
    p_src1 = p_dst_orig->p->p_pixels + i_x_offset * i_pix_pitch +
               p_filter->fmt_out.video.i_x_offset * i_pix_pitch +
               p_dst_orig->p->i_pitch *
               ( i_y_offset + p_filter->fmt_out.video.i_y_offset );

    i_src2_pitch = p_src->p[Y_PLANE].i_pitch;
    p_src2_y = p_src->p[Y_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset +
               p_src->p[Y_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;
    p_src2_u = p_src->p[U_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[U_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;
    p_src2_v = p_src->p[V_PLANE].p_pixels +
               p_filter->fmt_in.video.i_x_offset/2 +
               p_src->p[V_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset/2;

    p_trans = p_src->p[A_PLANE].p_pixels +
              p_filter->fmt_in.video.i_x_offset +
              p_src->p[A_PLANE].i_pitch * p_filter->fmt_in.video.i_y_offset;

    i_width = (i_width >> 1) << 1; /* Needs to be a multiple of 2 */

#define MAX_TRANS 255
#define TRANS_BITS  8

    /* Draw until we reach the bottom of the subtitle */
    for( i_y = 0; i_y < i_height; i_y++, p_trans += i_src2_pitch,
         p_dst += i_dst_pitch, p_src1 += i_src1_pitch,
         p_src2_y += i_src2_pitch, p_src2_u += i_src2_pitch,
         p_src2_v += i_src2_pitch )
    {
        /* Draw until we reach the end of the line */
        for( i_x = 0; i_x < i_width; i_x++, b_even = !b_even )
        {
            i_trans = ( p_trans[i_x] * i_alpha ) / 255;
            if( !i_trans )
            {
                /* Completely transparent. Don't change pixel */
            }
            else if( i_trans == MAX_TRANS )
            {
                /* Completely opaque. Completely overwrite underlying pixel */
                p_dst[i_x * 2]     = p_src2_y[i_x];

                if( b_even )
                {
                    p_dst[i_x * 2 + 1] = p_src2_u[i_x];
                    p_dst[i_x * 2 + 3] = p_src2_v[i_x];
                }
            }
            else
            {
                /* Blending */
                p_dst[i_x * 2]     = ( (uint16_t)p_src2_y[i_x] * i_trans +
                    (uint16_t)p_src1[i_x * 2] * (MAX_TRANS - i_trans) )
                    >> TRANS_BITS;

                if( b_even )
                {
                    p_dst[i_x * 2 + 1] = ( (uint16_t)p_src2_u[i_x] * i_trans +
                        (uint16_t)p_src1[i_x * 2 + 1] * (MAX_TRANS - i_trans) )
                        >> TRANS_BITS;
                    p_dst[i_x * 2 + 3] = ( (uint16_t)p_src2_v[i_x] * i_trans +
                        (uint16_t)p_src1[i_x * 2 + 3] * (MAX_TRANS - i_trans) )
                        >> TRANS_BITS;
                }
            }
        }
    }

#undef MAX_TRANS
#undef TRANS_BITS

    return;
}