vout_pictures.c

video linux conference

/*****************************************************************************
 * vout_pictures.c : picture management functions
 *****************************************************************************
 * Copyright (C) 2000-2004 VideoLAN
 * $Id: vout_pictures.c 10184 2005-03-07 17:52:05Z gbazin $
 *
 * Authors: Vincent Seguin <[e-mail]>
 *          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>                                                /* free() */
#include <stdio.h>                                              /* sprintf() */
#include <string.h>                                            /* strerror() */

#include <vlc/vlc.h>

#include "vlc_video.h"
#include "video_output.h"
#include "vlc_spu.h"

#include "vout_pictures.h"

/**
 * Display a picture
 *
 * Remove the reservation flag of a picture, which will cause it to be ready
 * for display. The picture won't be displayed until vout_DatePicture has been
 * called.
 */
void vout_DisplayPicture( vout_thread_t *p_vout, picture_t *p_pic )
{
    vlc_mutex_lock( &p_vout->picture_lock );
    switch( p_pic->i_status )
    {
    case RESERVED_PICTURE:
        p_pic->i_status = RESERVED_DISP_PICTURE;
        break;
    case RESERVED_DATED_PICTURE:
        p_pic->i_status = READY_PICTURE;
        break;
    default:
        msg_Err( p_vout, "picture to display %p has invalid status %d",
                         p_pic, p_pic->i_status );
        break;
    }

    vlc_mutex_unlock( &p_vout->picture_lock );
}

/**
 * Date a picture
 *
 * Remove the reservation flag of a picture, which will cause it to be ready
 * for display. The picture won't be displayed until vout_DisplayPicture has
 * been called.
 * \param p_vout The vout in question
 * \param p_pic The picture to date
 * \param date The date to display the picture
 */
void vout_DatePicture( vout_thread_t *p_vout,
                       picture_t *p_pic, mtime_t date )
{
    vlc_mutex_lock( &p_vout->picture_lock );
    p_pic->date = date;
    switch( p_pic->i_status )
    {
    case RESERVED_PICTURE:
        p_pic->i_status = RESERVED_DATED_PICTURE;
        break;
    case RESERVED_DISP_PICTURE:
        p_pic->i_status = READY_PICTURE;
        break;
    default:
        msg_Err( p_vout, "picture to date %p has invalid status %d",
                         p_pic, p_pic->i_status );
        break;
    }

    vlc_mutex_unlock( &p_vout->picture_lock );
}

/**
 * Allocate a picture in the video output heap.
 *
 * This function creates a reserved image in the video output heap.
 * A null pointer is returned if the function fails. This method provides an
 * already allocated zone of memory in the picture data fields.
 * It needs locking since several pictures can be created by several producers
 * threads.
 */
picture_t *vout_CreatePicture( vout_thread_t *p_vout,
                               vlc_bool_t b_progressive,
                               vlc_bool_t b_top_field_first,
                               unsigned int i_nb_fields )
{
    int         i_pic;                                      /* picture index */
    picture_t * p_pic;
    picture_t * p_freepic = NULL;                      /* first free picture */

    /* Get lock */
    vlc_mutex_lock( &p_vout->picture_lock );

    /*
     * Look for an empty place in the picture heap.
     */
    for( i_pic = 0; i_pic < I_RENDERPICTURES; i_pic++ )
    {
        p_pic = PP_RENDERPICTURE[(p_vout->render.i_last_used_pic + i_pic + 1)
                                 % I_RENDERPICTURES];

        switch( p_pic->i_status )
        {
            case DESTROYED_PICTURE:
                /* Memory will not be reallocated, and function can end
                 * immediately - this is the best possible case, since no
                 * memory allocation needs to be done */
                p_pic->i_status   = RESERVED_PICTURE;
                p_pic->i_refcount = 0;
                p_pic->b_force    = 0;

                p_pic->b_progressive        = b_progressive;
                p_pic->i_nb_fields          = i_nb_fields;
                p_pic->b_top_field_first    = b_top_field_first;

                p_vout->i_heap_size++;
                p_vout->render.i_last_used_pic =
                    ( p_vout->render.i_last_used_pic + i_pic + 1 )
                    % I_RENDERPICTURES;
                vlc_mutex_unlock( &p_vout->picture_lock );
                return( p_pic );

            case FREE_PICTURE:
                /* Picture is empty and ready for allocation */
                p_vout->render.i_last_used_pic =
                    ( p_vout->render.i_last_used_pic + i_pic + 1 )
                    % I_RENDERPICTURES;
                p_freepic = p_pic;
                break;

            default:
                break;
        }
    }

    /*
     * Prepare picture
     */
    if( p_freepic != NULL )
    {
        vout_AllocatePicture( VLC_OBJECT(p_vout),
                              p_freepic, p_vout->render.i_chroma,
                              p_vout->render.i_width, p_vout->render.i_height,
                              p_vout->render.i_aspect );

        if( p_freepic->i_planes )
        {
            /* Copy picture information, set some default values */
            p_freepic->i_status   = RESERVED_PICTURE;
            p_freepic->i_type     = MEMORY_PICTURE;
            p_freepic->b_slow     = 0;

            p_freepic->i_refcount = 0;
            p_freepic->b_force = 0;

            p_freepic->b_progressive        = b_progressive;
            p_freepic->i_nb_fields          = i_nb_fields;
            p_freepic->b_top_field_first    = b_top_field_first;

            p_freepic->i_matrix_coefficients = 1;

            p_vout->i_heap_size++;
        }
        else
        {
            /* Memory allocation failed : set picture as empty */
            p_freepic->i_status = FREE_PICTURE;
            p_freepic = NULL;

            msg_Err( p_vout, "picture allocation failed" );
        }

        vlc_mutex_unlock( &p_vout->picture_lock );

        return( p_freepic );
    }

    /* No free or destroyed picture could be found, but the decoder
     * will try again in a while. */
    vlc_mutex_unlock( &p_vout->picture_lock );

    return( NULL );
}

/**
 * Remove a permanent or reserved picture from the heap
 *
 * This function frees a previously reserved picture or a permanent
 * picture. It is meant to be used when the construction of a picture aborted.
 * Note that the picture will be destroyed even if it is linked !
 */
void vout_DestroyPicture( vout_thread_t *p_vout, picture_t *p_pic )
{
    vlc_mutex_lock( &p_vout->picture_lock );

#ifdef DEBUG
    /* Check if picture status is valid */
    if( (p_pic->i_status != RESERVED_PICTURE) &&
        (p_pic->i_status != RESERVED_DATED_PICTURE) &&
        (p_pic->i_status != RESERVED_DISP_PICTURE) )
    {
        msg_Err( p_vout, "picture to destroy %p has invalid status %d",
                         p_pic, p_pic->i_status );
    }
#endif

    p_pic->i_status = DESTROYED_PICTURE;
    p_vout->i_heap_size--;

    vlc_mutex_unlock( &p_vout->picture_lock );
}

/**
 * Increment reference counter of a picture
 *
 * This function increments the reference counter of a picture in the video
 * heap. It needs a lock since several producer threads can access the picture.
 */
void vout_LinkPicture( vout_thread_t *p_vout, picture_t *p_pic )
{
    vlc_mutex_lock( &p_vout->picture_lock );
    p_pic->i_refcount++;
    vlc_mutex_unlock( &p_vout->picture_lock );
}

/**
 * Decrement reference counter of a picture
 *
 * This function decrement the reference counter of a picture in the video heap
 */
void vout_UnlinkPicture( vout_thread_t *p_vout, picture_t *p_pic )
{
    vlc_mutex_lock( &p_vout->picture_lock );
    p_pic->i_refcount--;

    if( p_pic->i_refcount < 0 )
    {
        msg_Err( p_vout, "picture %p refcount is %i",
                 p_pic, p_pic->i_refcount );
        p_pic->i_refcount = 0;
    }

    if( ( p_pic->i_refcount == 0 ) &&
        ( p_pic->i_status == DISPLAYED_PICTURE ) )
    {
        p_pic->i_status = DESTROYED_PICTURE;
        p_vout->i_heap_size--;
    }

    vlc_mutex_unlock( &p_vout->picture_lock );
}

/**
 * Render a picture
 *
 * This function chooses whether the current picture needs to be copied
 * before rendering, does the subpicture magic, and tells the video output
 * thread which direct buffer needs to be displayed.
 */
picture_t * vout_RenderPicture( vout_thread_t *p_vout, picture_t *p_pic,
                                                       subpicture_t *p_subpic )
{
    int i_scale_width, i_scale_height;

    if( p_pic == NULL )
    {
        /* XXX: subtitles */
        return NULL;
    }

    i_scale_width = p_vout->fmt_out.i_visible_width * 1000 /
        p_vout->fmt_in.i_visible_width;
    i_scale_height = p_vout->fmt_out.i_visible_height * 1000 /
        p_vout->fmt_in.i_visible_height;

    if( p_pic->i_type == DIRECT_PICTURE )
    {
        if( !p_vout->render.b_allow_modify_pics || p_pic->i_refcount ||
            p_pic->b_force )
        {
            /* Picture is in a direct buffer and is still in use,
             * we need to copy it to another direct buffer before
             * displaying it if there are subtitles. */
            if( p_subpic != NULL )
            {
                /* We have subtitles. First copy the picture to
                 * the spare direct buffer, then render the
                 * subtitles. */
                vout_CopyPicture( p_vout, PP_OUTPUTPICTURE[0], p_pic );

                spu_RenderSubpictures( p_vout->p_spu, &p_vout->fmt_out,
                                       PP_OUTPUTPICTURE[0], p_pic, p_subpic,
                                       i_scale_width, i_scale_height );