Skip to content

GitLab

Commit 7bca0d7b authored by Rocky Bernstein's avatar Rocky Bernstein
Browse files

Attempt to make easier to understand and easier to complete.

parent 78e3a1d6
Hide whitespace changes
Inline Side-by-side
modules/codec/ogt/render.c
View file @ 7bca0d7b
......@@ -2,7 +2,7 @@
* render.c : Philips OGT (SVCD Subtitle) renderer
*****************************************************************************
* Copyright (C) 2003 VideoLAN
* $Id: render.c,v 1.7 2004/01/01 15:56:56 rocky Exp $
* $Id: render.c,v 1.8 2004/01/02 04:44:34 rocky Exp $
*
* Author: Rocky Bernstein
* based on code from:
......@@ -123,34 +123,31 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
struct subpicture_sys_t *p_sys = p_spu->p_sys;
dbg_print( (DECODE_DBG_CALL|DECODE_DBG_RENDER),
"spu width: %d, height %d, pitch (%d, %d, %d)",
p_spu->i_width, p_spu->i_height,
"spu width x height: (%dx%d), x-y (%d,%d), yuv pitch (%d,%d,%d)",
p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y,
p_pic->Y_PITCH, p_pic->U_PITCH, p_pic->V_PITCH );
p_pixel_base = p_pic->p[Y_PLANE].p_pixels + p_spu->i_x + p_spu->i_width
+ p_pic->p[Y_PLANE].i_pitch * ( p_spu->i_y + p_spu->i_height );
p_pixel_base = p_pic->p[Y_PLANE].p_pixels + p_spu->i_x
+ p_pic->p[Y_PLANE].i_pitch * p_spu->i_y;
i_x_start = p_spu->i_width - p_sys->i_x_end;
i_y_start = p_pic->p[Y_PLANE].i_pitch
* (p_spu->i_height - p_sys->i_y_end );
i_x_start = p_sys->i_x_start;
i_y_start = p_pic->p[Y_PLANE].i_pitch * p_sys->i_y_start;
i_x_end = p_spu->i_width - p_sys->i_x_start;
i_y_end = p_pic->p[Y_PLANE].i_pitch
* (p_spu->i_height - p_sys->i_y_start );
i_x_end = p_sys->i_x_end;
i_y_end = p_pic->p[Y_PLANE].i_pitch * p_sys->i_y_end;
p_source = (ogt_yuvt_t *)p_sys->p_data;
/* Draw until we reach the bottom of the subtitle */
for( i_y = p_spu->i_height * p_pic->p[Y_PLANE].i_pitch ;
i_y ;
i_y -= p_pic->p[Y_PLANE].i_pitch )
for( i_y = 0;
i_y < p_spu->i_height * p_pic->p[Y_PLANE].i_pitch ;
i_y += p_pic->p[Y_PLANE].i_pitch )
{
/* printf("+++begin line: %d,\n", i++); */
/* Draw until we reach the end of the line */
for( i_x = p_spu->i_width ; i_x ; i_x--, p_source++ )
for( i_x = 0; i_x < p_spu->i_width; i_x++, p_source++ )
{
if( b_crop
&& ( i_x < i_x_start || i_x > i_x_end
|| i_y < i_y_start || i_y > i_y_end ) )
......@@ -172,10 +169,10 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
/* Completely opaque. Completely overwrite underlying
pixel with subtitle pixel. */
uint8_t *p_pixel = p_pixel_base - i_x - i_y;
uint16_t i_colprecomp =
(uint16_t) ( p_source->plane[Y_PLANE] * MAX_ALPHA );
*p_pixel = i_colprecomp >> ALPHA_SCALEDOWN;
/* This is the location that's going to get changed.*/
uint8_t *p_pixel = p_pixel_base + i_x + i_y;
*p_pixel = p_source->plane[Y_PLANE];
break;
}
......@@ -184,20 +181,36 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
{
/* Blend in underlying pixel subtitle pixel. */
/* To be able to scale correctly for full opaqueness, we
add 1 to the alpha. This means alpha value 0 won't
be completely transparent and is not correct, but
that's handled in a special case above anyway. */
uint8_t *p_pixel = p_pixel_base - i_x - i_y;
uint16_t i_colprecomp =
(uint16_t) ( p_source->plane[Y_PLANE]
* (uint16_t) (p_source->s.t+1) );
uint16_t i_destalpha = MAX_ALPHA - p_source->s.t;
/* This is the location that's going to get changed.*/
uint8_t *p_pixel = p_pixel_base + i_x + i_y;
/* This is the weighted part of the subtitle. The
color plane is 8 bits and transparancy is 4 bits so
when multiplied we get up to 12 bits.
*/
uint16_t i_sub_color =
(uint16_t) ( p_source->plane[Y_PLANE] *
(uint16_t) (p_source->s.t) );
/* This is the weighted part of the underlying pixel.
For the same reasons above, the result is up to 12
bits. However since the transparancies are
inverses, the sum of i_sub_color and i_pixel_color
will not exceed 12 bits.
*/
uint16_t i_pixel_color =
(uint16_t) ( *p_pixel *
(uint16_t) (MAX_ALPHA - p_source->s.t) ) ;
*p_pixel = ( i_colprecomp +
(uint16_t) (*p_pixel) * i_destalpha )
>> ALPHA_SCALEDOWN;
/* Scale the 12-bit result back down to 8 bits. A
precise scaling after adding the two components,
would divide by one less than a power of 2. However
to simplify and speed things we use a power of
2. This means the boundaries (either all
transparent and all opaque) aren't handled properly.
But we deal with them in special cases above. */
*p_pixel = ( i_sub_color + i_pixel_color ) >> 4;
break;
}
......@@ -206,38 +219,31 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
}
#if FIXED
for ( i_plane = U_PLANE; i_plane <= U_PLANE ; i_plane++ )
#if 0
for ( i_plane = U_PLANE; i_plane <= V_PLANE ; i_plane++ )
{
p_pixel_base = p_pic->p[i_plane].p_pixels
+ ( p_spu->i_x + p_spu->i_width
+ p_pic->p[i_plane].i_pitch * (p_spu->i_y + p_spu->i_height) )/2 ;
p_pixel_base = p_pic->p[i_plane].p_pixels + p_spu->i_x / 2
+ p_pic->p[i_plane].i_pitch * p_spu->i_y / 2;
i_x_start = (p_spu->i_width - p_sys->i_x_end) >> 1;
i_y_start = p_pic->p[i_plane].i_pitch
* (p_spu->i_height - p_sys->i_y_end );
i_x_end = (p_spu->i_width - p_sys->i_x_start ) >> 1;
i_y_end = p_pic->p[i_plane].i_pitch
* (p_spu->i_height - p_sys->i_y_start );
i_x_start = p_sys->i_x_start / 2;
i_y_start = p_pic->p[Y_PLANE].i_pitch * p_sys->i_y_start;
i_x_end = p_sys->i_x_end / 2;
i_y_end = p_pic->p[Y_PLANE].i_pitch * p_sys->i_y_end;
p_source = (ogt_yuvt_t *)p_sys->p_data;
/* Draw until we reach the bottom of the subtitle */
for( i_y = p_spu->i_height * p_pic->p[i_plane].i_pitch ;
i_y > 0;
i_y -= p_pic->p[i_plane].i_pitch )
for( i_y = 0;
i_y < p_spu->i_height * p_pic->p[i_plane].i_pitch ;
i_y += p_pic->p[i_plane].i_pitch )
{
vlc_bool_t high_nibble = VLC_TRUE;
/* printf("+++begin line: %d,\n", i++); */
/* Draw until we reach the end of the line */
for( i_x = p_spu->i_width / 2 ; i_x > 0 ; i_x--, p_source ++ )
for( i_x = 0; i_x < p_spu->i_width; i_x += 2, p_source += 2 )
{
high_nibble = !high_nibble;
if( b_crop
&& ( i_x < i_x_start || i_x > i_x_end
|| i_y < i_y_start || i_y > i_y_end ) )
......@@ -253,26 +259,23 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
case 0x00:
/* Completely transparent. Don't change pixel. */
break;
default:
case MAX_ALPHA:
{
/* Completely opaque. Completely overwrite underlying
pixel with subtitle pixel. */
uint8_t *p_pixel = p_pixel_base - (i_x - i_y) / 2;
uint16_t i_colprecomp =
(uint16_t) (p_source->plane[i_plane] >> 4);
if (high_nibble)
*p_pixel = (i_colprecomp << 4) | ((*p_pixel) & 0x0f);
else
*p_pixel = (i_colprecomp) | ((*p_pixel) & 0xf0);
/* This is the location that's going to get changed.*/
uint8_t *p_pixel = p_pixel_base + i_y/2 + i_x/2;
uint8_t alpha = p_source->plane[i_plane];
*p_pixel = ( ( *p_pixel * ( 0xFF - alpha ) ) >> 8 ) +
( 0x80 * alpha >> 8 );
break;
}
default:
#if 0
{
/* Blend in underlying pixel subtitle pixel. */
......@@ -281,25 +284,26 @@ static void RenderI420( vout_thread_t *p_vout, picture_t *p_pic,
alpha value 0 won't be completely transparent and
is not correct, but that's handled in a special
case above anyway. */
uint8_t *p_pixel = p_pixel_base - (i_x - i_y) / 2;
uint16_t i_colprecomp = (uint16_t)
(p_source->plane[i_plane]
* (uint16_t) (p_source->s.t+1)) >> (4+4);
uint16_t i_destalpha = (MAX_ALPHA - p_source->s.t) >> 4;
if (high_nibble)
*p_pixel =
(( (i_colprecomp) +
(((uint16_t) *p_pixel * i_destalpha) & 0x0f) ) <<4)
| ((*p_pixel) & 0x0f);
uint8_t *p_pixel = p_pixel_base + i_y/2 + i_x/2;
uint8_t low_val = *p_pixel & 0x0f;
uint8_t high_val = *p_pixel & 0xf0 >> 4;
uint16_t i_colprecomp = (p_source->plane[i_plane]
* (uint16_t) (p_source->s.t+1)) >> 4;
uint8_t i_destalpha = MAX_ALPHA - p_source->s.t;
uint16_t new_low = ( i_colprecomp + low_val*i_destalpha )
/ 2;
uint16_t new_high;
else
*p_pixel =
( (i_colprecomp) +
(((uint16_t) *p_pixel * i_destalpha) & 0x0f) )
| ((*p_pixel) & 0xf0);
p_source++;
i_colprecomp = (p_source->plane[i_plane]
* (uint16_t) (p_source->s.t+1)) >> 4;
i_destalpha = MAX_ALPHA - p_source->s.t;
new_high = ( i_colprecomp + high_val*i_destalpha ) / 2;
*p_pixel = (new_high << 4) | new_low;
break;
}
#endif
}
}
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment

VideoLAN code repository instance