static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
{
- mlt_frame_get_image( this, image, format, width, height, 1 );
- uint8_t *p = *image;
- uint8_t *q = *image + *width * *height * 2;
+ int error = mlt_frame_get_image( this, image, format, width, height, 1 );
- // Get the gamma value
- double gamma = mlt_properties_get_double( mlt_frame_properties( this ), "gamma" );
+ if ( error == 0 && *format == mlt_image_yuv422 )
+ {
+ // Get the gamma value
+ double gamma = mlt_properties_get_double( mlt_frame_properties( this ), "gamma" );
- // Calculate the look up table
- double exp = 1 / gamma;
- uint8_t lookup[ 256 ];
- int i;
+ if ( gamma != 1.0 )
+ {
+ uint8_t *p = *image;
+ uint8_t *q = *image + *width * *height * 2;
- for( i = 0; i < 256; i ++ )
- lookup[ i ] = ( uint8_t )( pow( ( double )i / 255.0, exp ) * 255 );
+ // Calculate the look up table
+ double exp = 1 / gamma;
+ uint8_t lookup[ 256 ];
+ int i;
- while ( p != q )
- {
- *p = lookup[ *p ];
- p += 2;
+ for( i = 0; i < 256; i ++ )
+ lookup[ i ] = ( uint8_t )( pow( ( double )i / 255.0, exp ) * 255 );
+
+ while ( p != q )
+ {
+ *p = lookup[ *p ];
+ p += 2;
+ }
+ }
}
return 0;
static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
{
double gamma = mlt_properties_get_double( mlt_filter_properties( this ), "gamma" );
- gamma = gamma <= 0 ? 2 : gamma;
- mlt_frame_push_get_image( frame, filter_get_image );
+ gamma = gamma <= 0 ? 1 : gamma;
mlt_properties_set_double( mlt_frame_properties( frame ), "gamma", gamma );
+ mlt_frame_push_get_image( frame, filter_get_image );
return frame;
}
mlt_filter filter_gamma_init( char *arg )
{
- mlt_filter this = calloc( sizeof( struct mlt_filter_s ), 1 );
+ mlt_filter this = mlt_filter_new( );
if ( this != NULL )
{
- mlt_filter_init( this, NULL );
this->process = filter_process;
- if ( arg != NULL )
- mlt_properties_set_double( mlt_filter_properties( this ), "gamma", atof( arg ) );
+ mlt_properties_set( mlt_filter_properties( this ), "gamma", arg == NULL ? "1" : arg );
}
return this;
}
-