[melted] / src / modules / core / transition_luma.c

/*
 * transition_luma.c -- a generic dissolve/wipe processor
 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
 * Author: Dan Dennedy <dan@dennedy.org>
 *
 * 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_luma.h"
#include <framework/mlt_frame.h>

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

/** Luma class.
*/

typedef struct 
{
        struct mlt_transition_s parent;
        char *filename;
        int width;
        int height;                                                     
        float *bitmap;
}
transition_luma;


// forward declarations
static void transition_close( mlt_transition parent );


// image processing functions

static inline float smoothstep( float edge1, float edge2, float a )
{
        if ( a < edge1 )
                return 0.0;

        if ( a >= edge2 )
                return 1.0;

        a = ( a - edge1 ) / ( edge2 - edge1 );

        return ( a * a * ( 3 - 2 * a ) );
}

static int frame_composite_yuv( mlt_frame this, mlt_frame that, int x, int y, float weight, int *width, int *height )
{
        int ret = 0;
        int width_src = *width, height_src = *height;
        int width_dest = *width, height_dest = *height;
        mlt_image_format format_src = mlt_image_yuv422, format_dest = mlt_image_yuv422;
        uint8_t *p_src, *p_dest;
        int i, j;
        int stride_src;
        int stride_dest;
        int x_src = 0, y_src = 0;

        // optimization point - no work to do
        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( this, &p_dest, &format_dest, &width_dest, &height_dest, 1 /* writable */ );
        mlt_frame_get_image( that, &p_src, &format_src, &width_src, &height_src, 0 /* 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;
}

/** powerful stuff

    \param field_order -1 = progressive, 0 = lower field first, 1 = top field first
*/
static void luma_composite( mlt_frame a_frame, mlt_frame b_frame, int luma_width, int luma_height,
                                                        float *luma_bitmap, float pos, float frame_delta, float softness, int field_order,
                                                        int *width, int *height )
{
        int width_src = *width, height_src = *height;
        int width_dest = *width, height_dest = *height;
        mlt_image_format format_src = mlt_image_yuv422, format_dest = mlt_image_yuv422;
        uint8_t *p_src, *p_dest;
        int i, j;
        int stride_src;
        int stride_dest;
        float weight = 0;
        int field;

        format_src = mlt_image_yuv422;
        format_dest = mlt_image_yuv422;

        mlt_frame_get_image( a_frame, &p_dest, &format_dest, &width_dest, &height_dest, 1 /* writable */ );
        mlt_frame_get_image( b_frame, &p_src, &format_src, &width_src, &height_src, 0 /* writable */ );

        stride_src = width_src * 2;
        stride_dest = width_dest * 2;

        // Offset the position based on which field we're looking at ...
        float field_pos[ 2 ];
        field_pos[ 0 ] = pos + ( ( field_order == 0 ? 1 : 0 ) * frame_delta * 0.5 );
        field_pos[ 1 ] = pos + ( ( field_order == 0 ? 0 : 1 ) * frame_delta * 0.5 );

        // adjust the position for the softness level
        field_pos[ 0 ] *= ( 1.0 + softness );
        field_pos[ 1 ] *= ( 1.0 + softness );

        uint8_t *p;
        uint8_t *q;
        uint8_t *o;
        float  *l;

        uint8_t y;
        uint8_t uv;
        float value;

        float x_diff = ( float )luma_width / ( float )*width;
        float y_diff = ( float )luma_height / ( float )*height;

        // composite using luma map
        for ( field = 0; field < ( field_order < 0 ? 1 : 2 ); ++field )
        {
                for ( i = field; i < height_src; i += ( field_order < 0 ? 1 : 2 ) )
                {
                        p = &p_src[ i * stride_src ];
                        q = &p_dest[ i * stride_dest ];
                        o = &p_dest[ i * stride_dest ];
                        l = &luma_bitmap[ ( int )( ( float )i * y_diff ) * luma_width ];

                        for ( j = 0; j < width_src; j ++ )
                        {
                                y = *p ++;
                                uv = *p ++;
                weight = l[ ( int )( ( float )j * x_diff ) ];
                                value = smoothstep( weight, weight + softness, field_pos[ field ] );

                                *o ++ = (uint8_t)( y * value + *q++ * ( 1 - value ) );
                                *o ++ = (uint8_t)( uv * value + *q++ * ( 1 - value ) );
                        }
                }
        }
}

/** Get the image.
*/

static int transition_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
{
        // Get the properties of the a frame
        mlt_properties a_props = mlt_frame_properties( this );

        // Get the b frame from the stack
        mlt_frame b_frame = mlt_frame_pop_frame( this );

        // Get the properties of the b frame
        mlt_properties b_props = mlt_frame_properties( b_frame );

        // Arbitrary composite defaults
        float frame_delta = 1 / mlt_properties_get_double( b_props, "fps" );
        float mix = mlt_properties_get_double( b_props, "image.mix" );
        int luma_width = mlt_properties_get_int( b_props, "luma.width" );
        int luma_height = mlt_properties_get_int( b_props, "luma.height" );
        float *luma_bitmap = mlt_properties_get_data( b_props, "luma.bitmap", NULL );
        float luma_softness = mlt_properties_get_double( b_props, "luma.softness" );
        int progressive = mlt_properties_get_int( b_props, "progressive" );
        int top_field_first =  mlt_properties_get_int( b_props, "top_field_first" );
        int reverse = mlt_properties_get_int( b_props, "luma.reverse" );

        // Honour the reverse here
        mix = reverse ? 1 - mix : mix;

        // Ensure we get scaling on the b_frame
        mlt_properties_set( b_props, "rescale.interp", "nearest" );

        if ( luma_width > 0 && luma_height > 0 && luma_bitmap != NULL )
                // Composite the frames using a luma map
                luma_composite( this, b_frame, luma_width, luma_height, luma_bitmap, mix, frame_delta,
                        luma_softness, progressive > 0 ? -1 : top_field_first, width, height );
        else
                // Dissolve the frames using the time offset for mix value
                frame_composite_yuv( this, b_frame, 0, 0, mix, width, height );

        // Extract the a_frame image info
        *width = mlt_properties_get_int( a_props, "width" );
        *height = mlt_properties_get_int( a_props, "height" );
        *image = mlt_properties_get_data( a_props, "image", NULL );

        return 0;
}

/** Load the luma map from PGM stream.
*/

static void luma_read_pgm( FILE *f, float **map, int *width, int *height )
{
        uint8_t *data = NULL;
        while (1)
        {
                char line[128];
                int i = 2;
                int maxval;
                int bpp;
                float *p;
                
                line[127] = '\0';

                // get the magic code
                if ( fgets( line, 127, f ) == NULL )
                        break;
                if ( line[0] != 'P' || line[1] != '5' )
                        break;

                // skip white space and see if a new line must be fetched
                for ( i = 2; i < 127 && line[i] != '\0' && isspace( line[i] ); i++ );
                if ( line[i] == '\0' && fgets( line, 127, f ) == NULL )
                        break;

                // get the dimensions
                if ( line[0] == 'P' )
                        i = sscanf( line, "P5 %d %d %d", width, height, &maxval );
                else
                        i = sscanf( line, "%d %d %d", width, height, &maxval );

                // get the height value, if not yet
                if ( i < 2 )
                {
                        if ( fgets( line, 127, f ) == NULL )
                                break;
                        i = sscanf( line, "%d", height );
                        if ( i == 0 )
                                break;
                        else
                                i = 2;
                }

                // get the maximum gray value, if not yet
                if ( i < 3 )
                {
                        if ( fgets( line, 127, f ) == NULL )
                                break;
                        i = sscanf( line, "%d", &maxval );
                        if ( i == 0 )
                                break;
                }

                // determine if this is one or two bytes per pixel
                bpp = maxval > 255 ? 2 : 1;
                        // allocate temporary storage for the raw data
                data = malloc( *width * *height * bpp );
                if ( data == NULL )
                        break;

                // read the raw data
                if ( fread( data, *width * *height * bpp, 1, f ) != 1 )
                        break;
                
                // allocate the luma bitmap
                *map =  p = (float*) malloc( *width * *height * sizeof( float ) );
                if ( *map == NULL )
                        break;

                // proces the raw data into the luma bitmap
                for ( i = 0; i < *width * *height * bpp; i += bpp )
                {
                        if ( bpp == 1 )
                                *p++ = (float) data[ i ] / (float) maxval;
                        else
                                *p++ = (float) ( ( data[ i ] << 8 ) + data[ i+1 ] ) / (float) maxval;
                }

                break;
        }
                
        if ( data != NULL )
                free( data );
}


/** Luma transition processing.
*/

static mlt_frame transition_process( mlt_transition transition, mlt_frame a_frame, mlt_frame b_frame )
{
        transition_luma *this = (transition_luma*) transition->child;

        // Get the properties of the transition
        mlt_properties properties = mlt_transition_properties( transition );
        
        // Get the properties of the b frame
        mlt_properties b_props = mlt_frame_properties( b_frame );

        // If the filename property changed, reload the map
        char *luma_file = mlt_properties_get( properties, "resource" );
        if ( luma_file != NULL && ( this->filename == NULL || ( this->filename && strcmp( luma_file, this->filename ) ) ) )
        {
                FILE *pipe;
                
                free( this->filename );
                this->filename = strdup( luma_file );
                pipe = fopen( luma_file, "r" );
                if ( pipe != NULL )
                {
                        free( this->bitmap );
                        luma_read_pgm( pipe, &this->bitmap, &this->width, &this->height );
                        fclose( pipe );
                }
        }

        // Determine the time position of this frame in the transition duration
        mlt_position in = mlt_transition_get_in( transition );
        mlt_position out = mlt_transition_get_out( transition );
        mlt_position time = mlt_frame_get_position( b_frame );
        float pos = ( float )( time - in ) / ( float )( out - in + 1 );
        
        // Set the b frame properties
        mlt_properties_set_double( b_props, "image.mix", pos );
        mlt_properties_set_int( b_props, "luma.width", this->width );
        mlt_properties_set_int( b_props, "luma.height", this->height );
        mlt_properties_set_data( b_props, "luma.bitmap", this->bitmap, 0, NULL, NULL );
        mlt_properties_set_int( b_props, "luma.reverse", mlt_properties_get_int( properties, "reverse" ) );
        mlt_properties_set_double( b_props, "luma.softness", mlt_properties_get_double( properties, "softness" ) );

        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_luma_init( char *lumafile )
{
        transition_luma *this = calloc( sizeof( transition_luma ), 1 );
        if ( this != NULL )
        {
                mlt_transition transition = &this->parent;
                mlt_transition_init( transition, this );
                transition->process = transition_process;
                transition->close = transition_close;
                mlt_properties_set( mlt_transition_properties( transition ), "resource", lumafile );
                return &this->parent;
        }
        return NULL;
}

/** Close the transition.
*/

static void transition_close( mlt_transition parent )
{
        transition_luma *this = (transition_luma*) parent->child;
        free( this->bitmap );
        free( this->filename );
        free( this );
}