crop.c

video linux conference

/*****************************************************************************
 * crop.c : Crop video plugin for vlc
 *****************************************************************************
 * Copyright (C) 2002, 2003 VideoLAN
 * $Id: crop.c 10145 2005-03-05 16:49:15Z gbazin $
 *
 * Authors: Samuel Hocevar <[e-mail]>
 *
 * 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, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <stdlib.h>                                      /* malloc(), free() */
#include <string.h>

#include <vlc/vlc.h>
#include <vlc/vout.h>

#include "filter_common.h"

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int  Create    ( vlc_object_t * );
static void Destroy   ( vlc_object_t * );

static int  Init      ( vout_thread_t * );
static void End       ( vout_thread_t * );
static int  Manage    ( vout_thread_t * );
static void Render    ( vout_thread_t *, picture_t * );

static void UpdateStats    ( vout_thread_t *, picture_t * );

static int  SendEvents( vlc_object_t *, char const *,
                        vlc_value_t, vlc_value_t, void * );

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define GEOMETRY_TEXT N_("Crop geometry (pixels)")
#define GEOMETRY_LONGTEXT N_("Set the geometry of the zone to crop. This is set as <width> x <height> + <left offset> + <top offset>.")

#define AUTOCROP_TEXT N_("Automatic cropping")
#define AUTOCROP_LONGTEXT N_("Activate automatic black border cropping.")

vlc_module_begin();
    set_description( _("Crop video filter") );
    set_shortname( N_("Crop" ));
    set_category( CAT_VIDEO );
    set_subcategory( SUBCAT_VIDEO_VFILTER );
    set_capability( "video filter", 0 );

    add_string( "crop-geometry", NULL, NULL, GEOMETRY_TEXT, GEOMETRY_LONGTEXT, VLC_FALSE );
    add_bool( "autocrop", 0, NULL, AUTOCROP_TEXT, AUTOCROP_LONGTEXT, VLC_FALSE );

    add_shortcut( "crop" );
    set_callbacks( Create, Destroy );
vlc_module_end();

/*****************************************************************************
 * vout_sys_t: Crop video output method descriptor
 *****************************************************************************
 * This structure is part of the video output thread descriptor.
 * It describes the Crop specific properties of an output thread.
 *****************************************************************************/
struct vout_sys_t
{
    vout_thread_t *p_vout;

    unsigned int i_x, i_y;
    unsigned int i_width, i_height, i_aspect;

    vlc_bool_t b_autocrop;

    /* Autocrop specific variables */
    unsigned int i_lastchange;
    vlc_bool_t   b_changed;
};

/*****************************************************************************
 * Control: control facility for the vout (forwards to child vout)
 *****************************************************************************/
static int Control( vout_thread_t *p_vout, int i_query, va_list args )
{
    return vout_vaControl( p_vout->p_sys->p_vout, i_query, args );
}

/*****************************************************************************
 * Create: allocates Crop video thread output method
 *****************************************************************************
 * This function allocates and initializes a Crop vout method.
 *****************************************************************************/
static int Create( vlc_object_t *p_this )
{
    vout_thread_t *p_vout = (vout_thread_t *)p_this;

    /* Allocate structure */
    p_vout->p_sys = malloc( sizeof( vout_sys_t ) );
    if( p_vout->p_sys == NULL )
    {
        msg_Err( p_vout, "out of memory" );
        return VLC_ENOMEM;
    }

    p_vout->pf_init = Init;
    p_vout->pf_end = End;
    p_vout->pf_manage = Manage;
    p_vout->pf_render = Render;
    p_vout->pf_display = NULL;
    p_vout->pf_control = Control;

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Init: initialize Crop video thread output method
 *****************************************************************************/
static int Init( vout_thread_t *p_vout )
{
    int   i_index;
    char *psz_var;
    picture_t *p_pic;
    video_format_t fmt = {0};

    I_OUTPUTPICTURES = 0;

    p_vout->p_sys->i_lastchange = 0;
    p_vout->p_sys->b_changed = VLC_FALSE;

    /* Initialize the output structure */
    p_vout->output.i_chroma = p_vout->render.i_chroma;
    p_vout->output.i_width  = p_vout->render.i_width;
    p_vout->output.i_height = p_vout->render.i_height;
    p_vout->output.i_aspect = p_vout->render.i_aspect;

    /* Shall we use autocrop ? */
    p_vout->p_sys->b_autocrop = config_GetInt( p_vout, "autocrop" );

    /* Get geometry value from the user */
    psz_var = config_GetPsz( p_vout, "crop-geometry" );
    if( psz_var )
    {
        char *psz_parser, *psz_tmp;

        psz_parser = psz_tmp = psz_var;
        while( *psz_tmp && *psz_tmp != 'x' ) psz_tmp++;

        if( *psz_tmp )
        {
            psz_tmp[0] = '\0';
            p_vout->p_sys->i_width = atoi( psz_parser );

            psz_parser = ++psz_tmp;
            while( *psz_tmp && *psz_tmp != '+' ) psz_tmp++;

            if( *psz_tmp )
            {
                psz_tmp[0] = '\0';
                p_vout->p_sys->i_height = atoi( psz_parser );

                psz_parser = ++psz_tmp;
                while( *psz_tmp && *psz_tmp != '+' ) psz_tmp++;

                if( *psz_tmp )
                {
                    psz_tmp[0] = '\0';
                    p_vout->p_sys->i_x = atoi( psz_parser );
                    p_vout->p_sys->i_y = atoi( ++psz_tmp );
                }
                else
                {
                    p_vout->p_sys->i_x = atoi( psz_parser );
                    p_vout->p_sys->i_y =
                     ( p_vout->output.i_height - p_vout->p_sys->i_height ) / 2;
                }
            }
            else
            {
                p_vout->p_sys->i_height = atoi( psz_parser );
                p_vout->p_sys->i_x =
                     ( p_vout->output.i_width - p_vout->p_sys->i_width ) / 2;
                p_vout->p_sys->i_y =
                     ( p_vout->output.i_height - p_vout->p_sys->i_height ) / 2;
            }
        }
        else
        {
            p_vout->p_sys->i_width = atoi( psz_parser );
            p_vout->p_sys->i_height = p_vout->output.i_height;
            p_vout->p_sys->i_x =
                     ( p_vout->output.i_width - p_vout->p_sys->i_width ) / 2;
            p_vout->p_sys->i_y =
                     ( p_vout->output.i_height - p_vout->p_sys->i_height ) / 2;
        }

        /* Check for validity */
        if( p_vout->p_sys->i_x + p_vout->p_sys->i_width
                                                   > p_vout->output.i_width )
        {
            p_vout->p_sys->i_x = 0;
            if( p_vout->p_sys->i_width > p_vout->output.i_width )
            {
                p_vout->p_sys->i_width = p_vout->output.i_width;
            }
        }

        if( p_vout->p_sys->i_y + p_vout->p_sys->i_height
                                                   > p_vout->output.i_height )
        {
            p_vout->p_sys->i_y = 0;
            if( p_vout->p_sys->i_height > p_vout->output.i_height )
            {
                p_vout->p_sys->i_height = p_vout->output.i_height;
            }
        }

        free( psz_var );
    }
    else
    {
        p_vout->p_sys->i_width  = p_vout->output.i_width;
        p_vout->p_sys->i_height = p_vout->output.i_height;
        p_vout->p_sys->i_x = p_vout->p_sys->i_y = 0;
    }

    /* Pheeew. Parsing done. */
    msg_Dbg( p_vout, "cropping at %ix%i+%i+%i, %sautocropping",
                     p_vout->p_sys->i_width, p_vout->p_sys->i_height,
                     p_vout->p_sys->i_x, p_vout->p_sys->i_y,
                     p_vout->p_sys->b_autocrop ? "" : "not " );

    /* Set current output image properties */
    p_vout->p_sys->i_aspect = p_vout->output.i_aspect
                            * p_vout->output.i_height / p_vout->p_sys->i_height
                            * p_vout->p_sys->i_width / p_vout->output.i_width;

    fmt.i_width = fmt.i_visible_width = p_vout->p_sys->i_width;
    fmt.i_height = fmt.i_visible_height = p_vout->p_sys->i_height;
    fmt.i_x_offset = fmt.i_y_offset = 0;
    fmt.i_chroma = p_vout->render.i_chroma;
    fmt.i_aspect = p_vout->p_sys->i_aspect;
    fmt.i_sar_num = p_vout->p_sys->i_aspect * fmt.i_height / fmt.i_width;
    fmt.i_sar_den = VOUT_ASPECT_FACTOR;

    /* Try to open the real video output */
    p_vout->p_sys->p_vout = vout_Create( p_vout, &fmt );
    if( p_vout->p_sys->p_vout == NULL )
    {
        msg_Err( p_vout, "failed to create vout" );
        return VLC_EGENERIC;
    }

    ALLOCATE_DIRECTBUFFERS( VOUT_MAX_PICTURES );

    ADD_CALLBACKS( p_vout->p_sys->p_vout, SendEvents );