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

/*
 * filter_mirror.c -- mirror filter
 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
 * Author: Charles Yates <charles.yates@pandora.be>
 *
 * 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 "filter_mirror.h"

#include <framework/mlt_frame.h>

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

/** Do it :-).
*/

static int filter_get_image( mlt_frame frame, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
{
        // Pop the mirror filter from the stack
        mlt_filter this = mlt_frame_pop_service( frame );

        // Get the mirror type
        mlt_properties properties = mlt_filter_properties( this );

        // Get the properties
        char *mirror = mlt_properties_get( properties, "mirror" );

        // Determine if reverse is required
        int reverse = mlt_properties_get_int( properties, "reverse" );

        // Get the image
        int error = mlt_frame_get_image( frame, image, format, width, height, 1 );

        // If we have an image of the right colour space
        if ( error == 0 && *format == mlt_image_yuv422 )
        {
                // We'll KISS here
                int hh = *height / 2;

                if ( !strcmp( mirror, "horizontal" ) )
                {
                        uint8_t *p = NULL;
                        uint8_t *q = NULL;
                        int i;
                        for ( i = 0; i < *height; i ++ )
                        {
                                p = ( uint8_t * )*image + i * *width * 2;
                                q = p + *width * 2;
                                if ( !reverse )
                                {
                                        while ( p != q )
                                        {
                                                *p ++ = *( q - 2 );
                                                *p ++ = *( q - 3 );
                                                *p ++ = *( q - 4 );
                                                *p ++ = *( q - 1 );
                                                q -= 4;
                                        }
                                }
                                else
                                {
                                        while ( p != q )
                                        {
                                                *( q - 2 ) = *p ++;
                                                *( q - 3 ) = *p ++;
                                                *( q - 4 ) = *p ++;
                                                *( q - 1 ) = *p ++;
                                                q -= 4;
                                        }
                                }
                        }
                }
                else if ( !strcmp( mirror, "vertical" ) )
                {
                        uint16_t *end = ( uint16_t *)*image + *width * *height;
                        uint16_t *p = NULL;
                        uint16_t *q = NULL;
                        int i;
                        int j;
                        for ( i = 0; i < hh; i ++ )
                        {
                                p = ( uint16_t * )*image + i * *width;
                                q = end - i * *width;
                                j = *width;
                                if ( !reverse )
                                {
                                        while ( j -- )
                                                *p ++ = *q ++;
                                }
                                else
                                {
                                        while ( j -- )
                                                *q ++ = *p ++;
                                }
                        }
                }
                else if ( !strcmp( mirror, "diagonal" ) )
                {
                        uint8_t *end = ( uint8_t *)*image + *width * *height * 2;
                        uint8_t *p = NULL;
                        uint8_t *q = NULL;
                        int i;
                        int j;
                        for ( i = 0; i < *height; i ++ )
                        {
                                p = ( uint8_t * )*image + i * *width * 2;
                                q = end - i * *width * 2;
                                j = ( ( *width * ( *height - i ) ) / *height ) / 2;
                                if ( !reverse )
                                {
                                        while ( j -- )
                                        {
                                                *p ++ = *( q - 2 );
                                                *p ++ = *( q - 3 );
                                                *p ++ = *( q - 4 );
                                                *p ++ = *( q - 1 );
                                                q -= 4;
                                        }
                                }
                                else
                                {
                                        while ( j -- )
                                        {
                                                *( q - 2 ) = *p ++;
                                                *( q - 3 ) = *p ++;
                                                *( q - 4 ) = *p ++;
                                                *( q - 1 ) = *p ++;
                                                q -= 4;
                                        }
                                }
                        }
                }
                else if ( !strcmp( mirror, "flip" ) )
                {
                        uint8_t t[ 4 ];
                        uint8_t *p = NULL;
                        uint8_t *q = NULL;
                        int i;
                        for ( i = 0; i < *height; i ++ )
                        {
                                p = ( uint8_t * )*image + i * *width * 2;
                                q = p + *width * 2;
                                while ( p != q )
                                {
                                        t[ 0 ] = p[ 0 ];
                                        t[ 1 ] = p[ 1 ];
                                        t[ 2 ] = p[ 2 ];
                                        t[ 3 ] = p[ 3 ];
                                        *p ++ = *( q - 2 );
                                        *p ++ = *( q - 3 );
                                        *p ++ = *( q - 4 );
                                        *p ++ = *( q - 1 );
                                        *( -- q ) = t[ 3 ];
                                        *( -- q ) = t[ 0 ];
                                        *( -- q ) = t[ 1 ];
                                        *( -- q ) = t[ 2 ];
                                }
                        }
                }
                else if ( !strcmp( mirror, "flop" ) )
                {
                        uint16_t *end = ( uint16_t *)*image + *width * *height;
                        uint16_t *p = NULL;
                        uint16_t *q = NULL;
                        uint16_t t;
                        int i;
                        int j;
                        for ( i = 0; i < hh; i ++ )
                        {
                                p = ( uint16_t * )*image + i * *width;
                                q = end - i * *width;
                                j = *width;
                                while ( j -- )
                                {
                                        t = *p;
                                        *p ++ = *q;
                                        *q ++ = t;
                                }
                        }
                }
        }

        // Return the error
        return error;
}

/** Filter processing.
*/

static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
{
        // Push the service on to the stack
        mlt_frame_push_service( frame, this );

        // Push the filter method on to the stack
        mlt_frame_push_service( frame, filter_get_image );

        return frame;
}

/** Constructor for the filter.
*/

mlt_filter filter_mirror_init( void *arg )
{
        // Construct a new filter
        mlt_filter this = mlt_filter_new( );

        // If we have a filter, initialise it
        if ( this != NULL )
        {
                // Get the properties
                mlt_properties properties = mlt_filter_properties( this );

                // Set the default mirror type
                mlt_properties_set_or_default( properties, "mirror", arg, "horizontal" );

                // Assign the process method
                this->process = filter_process;
        }

        // Return the filter
        return this;
}