src/framework/mlt_frame.c

[mlt] / src / modules / core / filter_rescale.c

diff --git a/src/modules/core/filter_rescale.c b/src/modules/core/filter_rescale.c
index 0305db4174026f9d14811fccd1cd26dab1170b37..19b087f1ad86e018dbf97b5445b021fe6a19b004 100644 (file)
--- a/src/modules/core/filter_rescale.c
+++ b/src/modules/core/filter_rescale.c
@@ -25,6 +25,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include <math.h>
 
 typedef int ( *image_scaler )( mlt_frame this, uint8_t **image, mlt_image_format iformat, mlt_image_format oformat, int iwidth, int iheight, int owidth, int oheight );
 
@@ -110,60 +111,26 @@ static int filter_scale( mlt_frame this, uint8_t **image, mlt_image_format iform
 
 static void scale_alpha( mlt_frame this, int iwidth, int iheight, int owidth, int oheight )
 {
-       int size = 0;
-       uint8_t *input = mlt_properties_get_data( MLT_FRAME_PROPERTIES( this ), "alpha", &size );
-       
-       if ( input != NULL && ( ( size == iwidth * iheight ) || size == ( iwidth * ( iheight + 1 ) ) ) )
+       uint8_t *output = NULL;
+       uint8_t *input = mlt_frame_get_alpha_mask( this );
+
+       if ( input != NULL )
        {
-               uint8_t *output = mlt_pool_alloc( owidth * oheight );
-
-               // Derived coordinates
-               int dy, dx;
-
-       // Calculate ranges
-       int out_x_range = owidth / 2;
-       int out_y_range = oheight / 2;
-       int in_x_range = iwidth / 2;
-       int in_y_range = iheight / 2;
-
-       // Output pointers
-       register uint8_t *out_line = output;
-       register uint8_t *out_ptr;
-
-       // Calculate a middle pointer
-       uint8_t *in_middle = input + iwidth * in_y_range + in_x_range;
-       uint8_t *in_line;
-
-               // Generate the affine transform scaling values
-               register int scale_width = ( iwidth << 16 ) / owidth;
-               register int scale_height = ( iheight << 16 ) / oheight;
-               register int base = 0;
-
-               int outer = out_x_range * scale_width;
-               int bottom = out_y_range * scale_height;
-
-       // Loop for the entirety of our output height.
-       for ( dy = - bottom; dy < bottom; dy += scale_height )
-       {
-               // Start at the beginning of the line
-               out_ptr = out_line;
-       
-               // Pointer to the middle of the input line
-               in_line = in_middle + ( dy >> 16 ) * iwidth;
-
-               // Loop for the entirety of our output row.
-               for ( dx = - outer; dx < outer; dx += scale_width )
-               {
-                               base = dx >> 15;
-                               *out_ptr ++ = *( in_line + base );
-               }
-
-               // Move to next output line
-               out_line += owidth;
-       }
-
-               this->get_alpha_mask = NULL;
-               mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output, 0, mlt_pool_release, NULL );
+               uint8_t *out_line;
+               int x, y;
+               int ox = ( iwidth << 10 ) / owidth;
+               int oy = ( iheight << 10 ) / oheight;
+
+               output = mlt_pool_alloc( owidth * oheight );
+               out_line = output;
+
+               // Loop for the entirety of our output height.
+               for ( y = 0; y < oheight; y ++ )
+                       for ( x = 0; x < owidth; x ++ )
+                               *out_line ++ = *( input + ( ( 512 + ( y * oy * iwidth ) + x * ox ) >> 10 ) );
+
+               // Set it back on the frame
+               mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output, owidth * oheight, mlt_pool_release, NULL );
        }
 }
 
@@ -224,7 +191,7 @@ static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *
                else
                {
                        // When no scaling is requested, revert the requested dimensions if possible
-                       mlt_properties_set_int( properties, "rescale_width", ( iwidth / 2 ) * 2 );
+                       mlt_properties_set_int( properties, "rescale_width", iwidth );
                        mlt_properties_set_int( properties, "rescale_height", iheight );
                }
        
@@ -285,6 +252,8 @@ static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *
                }
                else
                {
+                               // Scale the alpha
+                               scale_alpha( this, iwidth, iheight, owidth, oheight );
                        *width = iwidth;
                        *height = iheight;
                }