/* * transition_composite.c -- compose one image over another using alpha channel * Copyright (C) 2003-2004 Ushodaya Enterprises Limited * Author: Dan Dennedy * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "transition_composite.h" #include #include #include /** Geometry struct. */ struct geometry_s { float x; float y; float w; float h; float mix; }; /** Parse a geometry property string. */ static void geometry_parse( struct geometry_s *geometry, struct geometry_s *defaults, char *property ) { // Assign from defaults if available if ( defaults != NULL ) { geometry->x = defaults->x; geometry->y = defaults->y; geometry->w = defaults->w; geometry->h = defaults->h; geometry->mix = defaults->mix; } else { geometry->mix = 100; } // Parse the geomtry string if ( property != NULL ) sscanf( property, "%f,%f:%fx%f:%f", &geometry->x, &geometry->y, &geometry->w, &geometry->h, &geometry->mix ); } /** Calculate real geometry. */ static void geometry_calculate( struct geometry_s *output, struct geometry_s *in, struct geometry_s *out, float position ) { // Calculate this frames geometry output->x = in->x + ( out->x - in->x ) * position; output->y = in->y + ( out->y - in->y ) * position; output->w = in->w + ( out->w - in->w ) * position; output->h = in->h + ( out->h - in->h ) * position; output->mix = in->mix + ( out->mix - in->mix ) * position; } /** Calculate the position for this frame. */ static float position_calculate( mlt_transition this, mlt_frame frame ) { // Get the in and out position mlt_position in = mlt_transition_get_in( this ); mlt_position out = mlt_transition_get_out( this ); // Get the position of the frame mlt_position position = mlt_frame_get_position( frame ); // Now do the calcs return ( float )( position - in ) / ( float )( out - in + 1 ); } /** Composite function. */ static int composite_yuv( uint8_t *p_dest, mlt_image_format format_dest, int width_dest, int height_dest, mlt_frame that, struct geometry_s geometry ) { int ret = 0; uint8_t *p_src; int i, j; int stride_src; int stride_dest; int x_src = 0, y_src = 0; mlt_image_format format_src = format_dest; int x = ( int )( ( float )width_dest * geometry.x / 100 ); int y = ( int )( ( float )height_dest * geometry.y / 100 ); float weight = geometry.mix / 100; // Compute the dimensioning rectangle int width_src = ( int )( ( float )width_dest * geometry.w / 100 ); int height_src = ( int )( ( float )height_dest * geometry.h / 100 ); mlt_properties b_props = mlt_frame_properties( that ); mlt_transition this = mlt_properties_get_data( b_props, "transition_composite", NULL ); mlt_properties properties = mlt_transition_properties( this ); if ( mlt_properties_get( properties, "distort" ) == NULL && mlt_properties_get( mlt_frame_properties( that ), "real_width" ) != NULL ) { int width_b = mlt_properties_get_double( b_props, "real_width" ); int height_b = mlt_properties_get_double( b_props, "real_height" ); // Maximise the dimensioning rectangle to the aspect of the b_frame if ( mlt_properties_get_double( b_props, "aspect_ratio" ) * height_src > width_src ) height_src = ( double )width_src / mlt_properties_get_double( b_props, "aspect_ratio" ) + 0.5; else width_src = mlt_properties_get_double( b_props, "aspect_ratio" ) * height_src + 0.5; // See if we need to normalise pixel aspect ratio // We can use consumer_aspect_ratio because the a_frame will take on this aspect double aspect = mlt_properties_get_double( b_props, "consumer_aspect_ratio" ); if ( aspect != 0 ) { // Derive the consumer pixel aspect double oaspect = aspect / ( double )width_dest * height_dest; // Get the b frame pixel aspect - usually 1 double iaspect = mlt_properties_get_double( b_props, "aspect_ratio" ) / width_b * height_b; // Normalise pixel aspect if ( iaspect != 0 && iaspect != oaspect ) { width_b = iaspect / oaspect * ( double )width_b + 0.5; width_src = iaspect / oaspect * ( double )width_src + 0.5; } // Tell rescale not to normalise display aspect mlt_frame_set_aspect_ratio( that, aspect ); } // Adjust overall scale for consumer double consumer_scale = mlt_properties_get_double( b_props, "consumer_scale" ); if ( consumer_scale > 0 ) { width_b = consumer_scale * width_b + 0.5; height_b = consumer_scale * height_b + 0.5; } // fprintf( stderr, "bounding rect %dx%d for overlay %dx%d\n", width_src, height_src, width_b, height_b ); // Constrain the overlay to the dimensioning rectangle if ( width_b < width_src && height_b < height_src ) { width_src = width_b; height_src = height_b; } } else if ( mlt_properties_get( b_props, "real_width" ) != NULL ) { // Tell rescale not to normalise display aspect mlt_properties_set_double( b_props, "consumer_aspect_ratio", 0 ); } x -= x % 2; // optimization points - no work to do if ( width_src <= 0 || height_src <= 0 ) return ret; if ( ( x < 0 && -x >= width_src ) || ( y < 0 && -y >= height_src ) ) return ret; format_src = mlt_image_yuv422; format_dest = mlt_image_yuv422; mlt_frame_get_image( that, &p_src, &format_src, &width_src, &height_src, 1 /* writable */ ); stride_src = width_src * 2; stride_dest = width_dest * 2; // crop overlay off the left edge of frame if ( x < 0 ) { x_src = -x; width_src -= x_src; x = 0; } // crop overlay beyond right edge of frame else if ( x + width_src > width_dest ) width_src = width_dest - x; // crop overlay off the top edge of the frame if ( y < 0 ) { y_src = -y; height_src -= y_src; } // crop overlay below bottom edge of frame else if ( y + height_src > height_dest ) height_src = height_dest - y; // offset pointer into overlay buffer based on cropping p_src += x_src * 2 + y_src * stride_src; // offset pointer into frame buffer based upon positive, even coordinates only! p_dest += ( x < 0 ? 0 : x ) * 2 + ( y < 0 ? 0 : y ) * stride_dest; // Get the alpha channel of the overlay uint8_t *p_alpha = mlt_frame_get_alpha_mask( that ); // offset pointer into alpha channel based upon cropping if ( p_alpha ) p_alpha += x_src + y_src * stride_src / 2; uint8_t *p = p_src; uint8_t *q = p_dest; uint8_t *o = p_dest; uint8_t *z = p_alpha; uint8_t Y; uint8_t UV; uint8_t a; float value; // now do the compositing only to cropped extents for ( i = 0; i < height_src; i++ ) { p = p_src; q = p_dest; o = p_dest; z = p_alpha; for ( j = 0; j < width_src; j ++ ) { Y = *p ++; UV = *p ++; a = ( z == NULL ) ? 255 : *z ++; value = ( weight * ( float ) a / 255.0 ); *o ++ = (uint8_t)( Y * value + *q++ * ( 1 - value ) ); *o ++ = (uint8_t)( UV * value + *q++ * ( 1 - value ) ); } p_src += stride_src; p_dest += stride_dest; if ( p_alpha ) p_alpha += stride_src / 2; } return ret; } /** Get the image. */ static int transition_get_image( mlt_frame a_frame, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable ) { // Get the b frame from the stack mlt_frame b_frame = mlt_frame_pop_frame( a_frame ); // Get the image from the a frame mlt_frame_get_image( a_frame, image, format, width, height, 1 ); if ( b_frame != NULL ) { // Get the properties of the b frame mlt_properties b_props = mlt_frame_properties( b_frame ); // Get the transition from the b frame mlt_transition this = mlt_properties_get_data( b_props, "transition_composite", NULL ); // Get the properties from the transition mlt_properties properties = mlt_transition_properties( this ); // Structures for geometry struct geometry_s result; struct geometry_s start; struct geometry_s end; // Calculate the position float position = position_calculate( this, a_frame ); // Now parse the geometries geometry_parse( &start, NULL, mlt_properties_get( properties, "start" ) ); geometry_parse( &end, &start, mlt_properties_get( properties, "end" ) ); // Do the calculation geometry_calculate( &result, &start, &end, position ); // Since we are the consumer of the b_frame, we must pass along these // consumer properties from the a_frame mlt_properties_set_double( b_props, "consumer_aspect_ratio", mlt_properties_get_double( mlt_frame_properties( a_frame ), "consumer_aspect_ratio" ) ); mlt_properties_set_double( b_props, "consumer_scale", mlt_properties_get_double( mlt_frame_properties( a_frame ), "consumer_scale" ) ); // Composite the b_frame on the a_frame composite_yuv( *image, *format, *width, *height, b_frame, result ); } return 0; } /** Composition transition processing. */ static mlt_frame composite_process( mlt_transition this, mlt_frame a_frame, mlt_frame b_frame ) { // Propogate the transition properties to the b frame mlt_properties b_props = mlt_frame_properties( b_frame ); mlt_properties_set_data( b_props, "transition_composite", this, 0, NULL, NULL ); mlt_frame_push_get_image( a_frame, transition_get_image ); mlt_frame_push_frame( a_frame, b_frame ); return a_frame; } /** Constructor for the filter. */ mlt_transition transition_composite_init( char *arg ) { mlt_transition this = calloc( sizeof( struct mlt_transition_s ), 1 ); if ( this != NULL && mlt_transition_init( this, NULL ) == 0 ) { this->process = composite_process; mlt_properties_set( mlt_transition_properties( this ), "start", arg != NULL ? arg : "85,5:10x10" ); mlt_properties_set( mlt_transition_properties( this ), "end", "" ); } return this; }