/* * 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 #include /** Geometry struct. */ struct geometry_s { int nw; // normalised width int nh; // normalised height int sw; // scaled width, not including consumer scale based upon w/nw int sh; // scaled height, not including consumer scale based upon h/nh float x; float y; float w; float h; float mix; int halign; // horizontal alignment: 0=left, 1=center, 2=right int valign; // vertical alignment: 0=top, 1=middle, 2=bottom }; /** Parse a value from a geometry string. */ static float parse_value( char **ptr, int normalisation, char delim, float defaults ) { float value = defaults; if ( *ptr != NULL && **ptr != '\0' ) { char *end = NULL; value = strtod( *ptr, &end ); if ( end != NULL ) { if ( *end == '%' ) value = ( value / 100.0 ) * normalisation; while ( *end == delim || *end == '%' ) end ++; } *ptr = end; } return value; } /** Parse a geometry property string with the syntax X,Y:WxH:MIX. Any value can be expressed as a percentage by appending a % after the value, otherwise values are assumed to be relative to the normalised dimensions of the consumer. */ static void geometry_parse( struct geometry_s *geometry, struct geometry_s *defaults, char *property, int nw, int nh ) { // Assign normalised width and height geometry->nw = nw; geometry->nh = nh; // Assign from defaults if available if ( defaults != NULL ) { geometry->x = defaults->x; geometry->y = defaults->y; geometry->w = geometry->sw = defaults->w; geometry->h = geometry->sh = defaults->h; geometry->mix = defaults->mix; } else { geometry->mix = 100; } // Parse the geomtry string if ( property != NULL ) { char *ptr = property; geometry->x = parse_value( &ptr, nw, ',', geometry->x ); geometry->y = parse_value( &ptr, nh, ':', geometry->y ); geometry->w = geometry->sw = parse_value( &ptr, nw, 'x', geometry->w ); geometry->h = geometry->sh = parse_value( &ptr, nh, ':', geometry->h ); geometry->mix = parse_value( &ptr, 100, ' ', 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->nw = in->nw; output->nh = in->nh; output->x = in->x + ( out->x - in->x ) * position + 0.5; output->y = in->y + ( out->y - in->y ) * position + 0.5; 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; } /** Parse the alignment properties into the geometry. */ static int alignment_parse( char* align ) { int ret = 0; if ( align == NULL ); else if ( isdigit( align[ 0 ] ) ) ret = atoi( align ); else if ( align[ 0 ] == 'c' || align[ 0 ] == 'm' ) ret = 1; else if ( align[ 0 ] == 'r' || align[ 0 ] == 'b' ) ret = 2; return ret; } /** Adjust position according to scaled size and alignment properties. */ static void alignment_calculate( struct geometry_s *geometry ) { geometry->x += ( geometry->w - geometry->sw ) * geometry->halign / 2 + 0.5; geometry->y += ( geometry->h - geometry->sh ) * geometry->valign / 2 + 0.5; } /** 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 ); } /** Calculate the field delta for this frame - position between two frames. */ static float delta_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 float x = ( float )( position - in ) / ( float )( out - in + 1 ); position++; float y = ( float )( position - in ) / ( float )( out - in + 1 ); return ( y - x ) / 2.0; } static int get_value( mlt_properties properties, char *preferred, char *fallback ) { int value = mlt_properties_get_int( properties, preferred ); if ( value == 0 ) value = mlt_properties_get_int( properties, fallback ); return value; } /** Composite function. */ static int composite_yuv( uint8_t *p_dest, int width_dest, int height_dest, int bpp, uint8_t *p_src, int width_src, int height_src, uint8_t *p_alpha, struct geometry_s geometry, int field ) { int ret = 0; int i, j, k; int x_src = 0, y_src = 0; float weight = geometry.mix / 100; int stride_src = width_src * bpp; int stride_dest = width_dest * bpp; // Adjust to consumer scale int x = geometry.x * width_dest / geometry.nw + 0.5; int y = geometry.y * height_dest / geometry.nh + 0.5; if ( bpp == 2 ) 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; // 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 * bpp + y_src * stride_src; // offset pointer into frame buffer based upon positive coordinates only! p_dest += ( x < 0 ? 0 : x ) * bpp + ( y < 0 ? 0 : y ) * stride_dest; // offset pointer into alpha channel based upon cropping if ( p_alpha ) p_alpha += x_src + y_src * stride_src / bpp; // Assuming lower field first // Special care is taken to make sure the b_frame is aligned to the correct field. // field 0 = lower field and y should be odd (y is 0-based). // field 1 = upper field and y should be even. if ( ( field > -1 ) && ( y % 2 == field ) ) { if ( y == 0 ) p_dest += stride_dest; else p_dest -= stride_dest; } // On the second field, use the other lines from b_frame if ( field == 1 ) { p_src += stride_src; if ( p_alpha ) p_alpha += stride_src / bpp; height_src--; } uint8_t *p = p_src; uint8_t *q = p_dest; uint8_t *o = p_dest; uint8_t *z = p_alpha; uint8_t a; float value; int step = ( field > -1 ) ? 2 : 1; // now do the compositing only to cropped extents for ( i = 0; i < height_src; i += step ) { p = &p_src[ i * stride_src ]; q = &p_dest[ i * stride_dest ]; o = &p_dest[ i * stride_dest ]; if ( p_alpha ) z = &p_alpha[ i * stride_src / bpp ]; for ( j = 0; j < width_src; j ++ ) { a = ( z == NULL ) ? 255 : *z ++; value = ( weight * ( float ) a / 255.0 ); for ( k = 0; k < bpp; k ++ ) *o ++ = (uint8_t)( *p++ * value + *q++ * ( 1 - value ) ); } } return ret; } /** Get the properly sized image from b_frame. */ static int get_b_frame_image( mlt_frame b_frame, uint8_t **image, int *width, int *height, struct geometry_s *geometry ) { int ret = 0; mlt_image_format format = mlt_image_yuv422; // Initialise the scaled dimensions from the computed geometry->sw = geometry->w; geometry->sh = geometry->h; // Compute the dimensioning rectangle mlt_properties b_props = mlt_frame_properties( b_frame ); 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 ) { // Adjust b_frame pixel aspect int normalised_width = geometry->w; int normalised_height = geometry->h; int real_width = get_value( b_props, "real_width", "width" ); int real_height = get_value( b_props, "real_height", "height" ); double input_ar = mlt_frame_get_aspect_ratio( b_frame ); double output_ar = mlt_properties_get_double( b_props, "consumer_aspect_ratio" ); //int scaled_width = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_width; //int scaled_height = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_height; int scaled_width = real_width; int scaled_height = real_height; double output_sar = ( double ) geometry->nw / geometry->nh / output_ar; // We always normalise pixel aspect by requesting a larger than normal // image in order to maximise usage of the bounding rectangle // These calcs are optimised by reducing factors in equations if ( output_sar < 1.0 ) // If the output is skinny pixels (PAL) then stretch our input vertically // derived from: input_sar / output_sar * real_height scaled_height = ( double )real_width / input_ar / output_sar; else // If the output is fat pixels (NTSC) then stretch our input horizontally // derived from: output_sar / input_sar * real_width scaled_width = output_sar * real_height * input_ar; // fprintf( stderr, "composite: real %dx%d scaled %dx%d normalised %dx%d\n", real_width, real_height, scaled_width, scaled_height, normalised_width, normalised_height ); // Now ensure that our images fit in the normalised frame if ( scaled_width > normalised_width ) { scaled_height = scaled_height * normalised_width / scaled_width; scaled_width = normalised_width; } if ( scaled_height > normalised_height ) { scaled_width = scaled_width * normalised_height / scaled_height; scaled_height = normalised_height; } // Now we need to align to the geometry if ( scaled_width <= geometry->w && scaled_height <= geometry->h ) { // Save the new scaled dimensions geometry->sw = scaled_width; geometry->sh = scaled_height; } } // We want to ensure that we bypass resize now... mlt_properties_set( b_props, "distort", "true" ); // Take into consideration alignment for optimisation alignment_calculate( geometry ); // Adjust to consumer scale int x = geometry->x * *width / geometry->nw + 0.5; int y = geometry->y * *height / geometry->nh + 0.5; *width = geometry->sw * *width / geometry->nw; *height = geometry->sh * *height / geometry->nh; x -= x % 2; //fprintf( stderr, "composite calculated %d,%d:%dx%d\n", x, y, *width, *height ); // optimization points - no work to do if ( *width <= 0 || *height <= 0 ) return 1; if ( ( x < 0 && -x >= *width ) || ( y < 0 && -y >= *height ) ) return 1; ret = mlt_frame_get_image( b_frame, image, &format, width, height, 1 /* writable */ ); return ret; } static uint8_t *transition_get_alpha_mask( mlt_frame this ) { // Obtain properties of frame mlt_properties properties = mlt_frame_properties( this ); // Return the alpha mask return mlt_properties_get_data( properties, "alpha", NULL ); } /** 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 ); // This compositer is yuv422 only *format = mlt_image_yuv422; // 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 a frame mlt_properties a_props = mlt_frame_properties( a_frame ); // 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 ); float delta = delta_calculate( this, a_frame ); // Obtain the normalised width and height from the a_frame int normalised_width = mlt_properties_get_int( a_props, "normalised_width" ); int normalised_height = mlt_properties_get_int( a_props, "normalised_height" ); // Now parse the geometries geometry_parse( &start, NULL, mlt_properties_get( properties, "start" ), normalised_width, normalised_height ); geometry_parse( &end, &start, mlt_properties_get( properties, "end" ), normalised_width, normalised_height ); // Now parse the alignment result.halign = alignment_parse( mlt_properties_get( properties, "halign" ) ); result.valign = alignment_parse( mlt_properties_get( properties, "valign" ) ); // 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( a_props, "consumer_aspect_ratio" ) ); mlt_properties_set_double( b_props, "consumer_scale", mlt_properties_get_double( a_props, "consumer_scale" ) ); // Do the calculation geometry_calculate( &result, &start, &end, position ); // Get the image from the b frame uint8_t *image_b; int width_b = *width; int height_b = *height; if ( get_b_frame_image( b_frame, &image_b, &width_b, &height_b, &result ) == 0 ) { uint8_t *dest = *image; uint8_t *src = image_b; int bpp = 2; uint8_t *alpha = mlt_frame_get_alpha_mask( b_frame ); int progressive = mlt_properties_get_int( a_props, "progressive" ) || mlt_properties_get_int( a_props, "consumer_progressive" ) || mlt_properties_get_int( properties, "progressive" ); int field; // See if the alpha channel is our destination if ( mlt_properties_get( properties, "a_frame" ) != NULL ) { bpp = 1; // Get or make the a_frame alpha channel dest = mlt_frame_get_alpha_mask( a_frame ); if ( dest == NULL ) { // Allocate the alpha dest = mlt_pool_alloc( *width * *height ); mlt_properties_set_data( a_props, "alpha", dest, *width * *height, ( mlt_destructor )mlt_pool_release, NULL ); // Set alpha call back a_frame->get_alpha_mask = transition_get_alpha_mask; } // If the source is an image, convert its YUV to an alpha channel if ( mlt_properties_get( properties, "b_frame" ) == NULL ) { if ( alpha == NULL ) { // Allocate the alpha alpha = mlt_pool_alloc( width_b * height_b ); mlt_properties_set_data( b_props, "alpha", alpha, width_b * height_b, ( mlt_destructor )mlt_pool_release, NULL ); // Set alpha call back b_frame->get_alpha_mask = transition_get_alpha_mask; } // Copy the Y values into alpha uint8_t *p = image_b; uint8_t *q = alpha; int i; for ( i = 0; i < width_b * height_b; i ++, p += 2 ) *q ++ = *p; // Setup to composite from the alpha channel src = alpha; alpha = NULL; } } // See if the alpha channel is our source if ( mlt_properties_get( properties, "b_frame" ) != NULL ) { // If we do not have an alpha channel fabricate it if ( alpha == NULL ) { // Allocate the alpha alpha = mlt_pool_alloc( width_b * height_b ); mlt_properties_set_data( b_props, "alpha", alpha, width_b * height_b, ( mlt_destructor )mlt_pool_release, NULL ); // Set alpha call back b_frame->get_alpha_mask = transition_get_alpha_mask; // Copy the Y values into alpha uint8_t *p = image_b; uint8_t *q = alpha; int i; for ( i = 0; i < width_b * height_b; i ++, p += 2 ) *q ++ = *p; } // If the destination is image, convert the alpha channel to YUV if ( mlt_properties_get( properties, "a_frame" ) == NULL ) { uint8_t *p = alpha; uint8_t *q = image_b; int i; for ( i = 0; i < width_b * height_b; i ++, p ++ ) { *q ++ = 16 + ( ( float )*p / 255 * 220 ); // 220 is the luma range from 16-235 *q ++ = 128; } } else { // Setup to composite from the alpha channel src = alpha; bpp = 1; } // Never the apply the alpha channel to this type of operation alpha = NULL; } for ( field = 0; field < ( progressive ? 1 : 2 ); field++ ) { // Assume lower field (0) first float field_position = position + field * delta; // Do the calculation geometry_calculate( &result, &start, &end, field_position ); // Align alignment_calculate( &result ); // Composite the b_frame on the a_frame composite_yuv( dest, *width, *height, bpp, src, width_b, height_b, alpha, result, progressive ? -1 : field ); } } } 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%:10%x10%" ); mlt_properties_set( mlt_transition_properties( this ), "end", "" ); } return this; }