common.c

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/*****************************************************************************
 * Common SVCD and CVD subtitle routines.
 *****************************************************************************
 * Copyright (C) 2003, 2004 VideoLAN
 * $Id: common.c,v 1.13 2004/02/22 10:52:23 rocky Exp $
 *
 * Author: Rocky Bernstein <[e-mail]>
 *   based on code from:
 *       Julio Sanchez Fernandez (http://subhandler.sourceforge.net)
 *       Samuel Hocevar <[e-mail]>
 *       Laurent Aimar <[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 <vlc/vlc.h>
#include <vlc/vout.h>
#include <vlc/decoder.h>

#include "subtitle.h"
#include "pixmap.h"
#include "common.h"
#ifdef HAVE_LIBPNG
#include "write_png.h"
#endif

/*****************************************************************************
 Free Resources associated with subtitle packet.
 *****************************************************************************/
void VCDSubClose( vlc_object_t *p_this )
{
    decoder_t     *p_dec = (decoder_t*)p_this;
    decoder_sys_t *p_sys = p_dec->p_sys;

    dbg_print( (DECODE_DBG_CALL|DECODE_DBG_EXT) , "");

    if( !p_sys->b_packetizer )
    {
        /* FIXME check if it's ok to not lock vout */
        if( p_sys->p_vout != NULL && p_sys->p_vout->p_subpicture != NULL )
        {
            subpicture_t *  p_subpic;
            int             i_subpic;

            for( i_subpic = 0; i_subpic < VOUT_MAX_SUBPICTURES; i_subpic++ )
            {
                p_subpic = &p_sys->p_vout->p_subpicture[i_subpic];

                if( p_subpic != NULL &&
                    ( ( p_subpic->i_status == RESERVED_SUBPICTURE ) ||
                      ( p_subpic->i_status == READY_SUBPICTURE ) ) )
                {
                    vout_DestroySubPicture( p_sys->p_vout, p_subpic );
                }
            }
        }
    }

    if( p_sys->p_block )
    {
        block_ChainRelease( p_sys->p_block );
    }

    free(p_sys->subtitle_data);
    free( p_sys );
}

/*****************************************************************************

Initialize so the next packet will start off a new one.

 *****************************************************************************/
void 
VCDSubInitSubtitleBlock( decoder_sys_t * p_sys ) 
{
  p_sys->i_spu_size = 0;
  p_sys->state      = SUBTITLE_BLOCK_EMPTY;
  p_sys->i_spu      = 0;
  p_sys->p_block    = NULL;
  p_sys->subtitle_data_pos = 0;

}

void 
VCDSubInitSubtitleData(decoder_sys_t *p_sys)
{
  if ( p_sys->subtitle_data ) {
    if ( p_sys->subtitle_data_size < p_sys->i_spu_size ) {
      p_sys->subtitle_data = realloc(p_sys->subtitle_data,
				    p_sys->i_spu_size);
      p_sys->subtitle_data_size = p_sys->i_spu_size;
    }
  } else {
    p_sys->subtitle_data = malloc(p_sys->i_spu_size);
    p_sys->subtitle_data_size = p_sys->i_spu_size;
    /* FIXME: wrong place to get p_sys */
    p_sys->i_image = 0;
  }
  p_sys->subtitle_data_pos = 0;
}

void 
VCDSubAppendData ( decoder_t *p_dec, uint8_t *buffer, uint32_t buf_len )
{
  decoder_sys_t *p_sys = p_dec->p_sys;
  int chunk_length = buf_len;

  if ( chunk_length > p_sys->i_spu_size - p_sys->subtitle_data_pos ) {
    msg_Warn( p_dec, "too much data (%d) expecting at most %u",
	      chunk_length, p_sys->i_spu_size - p_sys->subtitle_data_pos );

    chunk_length = p_sys->i_spu_size - p_sys->subtitle_data_pos;
  }

  if ( chunk_length > 0 ) {
#if 0
    int i;
    int8_t *b=buffer;
    for (i=0; i<chunk_length; i++)
      printf ("%02x", b[i]);
    printf("\n");
#endif
    
    memcpy(p_sys->subtitle_data + p_sys->subtitle_data_pos,
	   buffer, chunk_length);
    p_sys->subtitle_data_pos += chunk_length;
    dbg_print(DECODE_DBG_PACKET, "%d bytes appended, pointer now %d",
	      chunk_length, p_sys->subtitle_data_pos);
  }
}


/*****************************************************************************
 * FindVout: Find a vout or wait for one to be created.
 *****************************************************************************/
vout_thread_t *VCDSubFindVout( decoder_t *p_dec )
{
    vout_thread_t *p_vout = NULL;

    /* Find an available video output */
    do
    {
        if( p_dec->b_die || p_dec->b_error )
        {
            break;
        }

        p_vout = vlc_object_find( p_dec, VLC_OBJECT_VOUT, FIND_ANYWHERE );
        if( p_vout )
        {
            break;
        }

        msleep( VOUT_OUTMEM_SLEEP );
    }
    while( 1 );

    return p_vout;
}



/**
   Remove color palette by expanding pixel entries to contain the
   palette values. We work from the free space at the end to the
   beginning so we can expand inline.
*/
static void
InlinePalette ( /*inout*/ uint8_t *p_dest, decoder_sys_t *p_sys )
{
  const unsigned int i_width  = p_sys->i_width;
  const unsigned int i_height = p_sys->i_height;
  int n = (i_height * i_width) - 1;
  uint8_t    *p_from = p_dest;
  ogt_yuvt_t *p_to   = (ogt_yuvt_t *) p_dest;
  
  for ( ; n >= 0 ; n-- ) {
    p_to[n] = p_sys->p_palette[p_from[n]];
    /*p_to[n] = p_sys->p_palette[p_from[3]];*/
  }
}

/**
   Check to see if user has overridden subtitle aspect ratio. 
   0 is returned for no override which means just counteract any
   scaling effects.
*/
unsigned int 
VCDSubGetAROverride(vlc_object_t * p_input, vout_thread_t *p_vout)
{
  char *psz_string = config_GetPsz( p_input, MODULE_STRING "-aspect-ratio" );

  /* Check whether the user tried to override aspect ratio */
  if( !psz_string ) return 0;

  {
    unsigned int i_new_aspect = 0;
    char *psz_parser = strchr( psz_string, ':' );
    
    if( psz_parser )
      {
	*psz_parser++ = '\0';
	i_new_aspect = atoi( psz_string ) * VOUT_ASPECT_FACTOR
	  / atoi( psz_parser );
      }
    else
      {
	i_new_aspect = p_vout->output.i_width * VOUT_ASPECT_FACTOR
	  * atof( psz_string )
	  / p_vout->output.i_height;
      }
    
    return i_new_aspect;
  }
}


/**
   Scales down (reduces size) of p_dest in the x direction as 
   determined through aspect ratio x_scale by y_scale. Scaling
   is done in place. p_spu->i_width, is updated to new width

   The aspect ratio is assumed to be between 1/2 and 1.

   Note: the scaling truncates the new width rather than rounds it.
   Perhaps something one might want to address.
*/
void
VCDSubScaleX( decoder_t *p_dec, subpicture_t *p_spu, 
	      unsigned int i_scale_x, unsigned int i_scale_y )
{
  int i_row, i_col;

  decoder_sys_t *p_sys = p_dec->p_sys;
  uint8_t *p_src1 = p_spu->p_sys->p_data;
  uint8_t *p_src2 = p_src1 + PIXEL_SIZE;
  uint8_t *p_dst  = p_src1;
  unsigned int i_new_width = (p_spu->i_width * i_scale_x) / i_scale_y ;
  unsigned int i_used=0;  /* Number of bytes used up in p_src1. */

  dbg_print( (DECODE_DBG_CALL|DECODE_DBG_TRANSFORM) , 
	     "aspect ratio %i:%i, Old width: %d, new width: %d", 
	     i_scale_x, i_scale_y, p_spu->i_width, i_new_width);

  if (! (i_scale_x < i_scale_y && i_scale_y < i_scale_x+i_scale_x) )
    {
      msg_Warn( p_dec, "Need x < y < 2x. x: %i, y: %i", i_scale_x, i_scale_y );
      return;
    }
  
  for ( i_row=0; i_row <= p_spu->i_height - 1; i_row++ ) {

    if (i_used != 0) {
      /* Discard the remaining piece of the column of the previous line*/
      i_used=0;
      p_src1 = p_src2;
      p_src2 += PIXEL_SIZE;
    }
    
    for ( i_col=0; i_col <= p_spu->i_width - 2; i_col++ ) {
      unsigned int i;
      unsigned int w1= i_scale_x - i_used;
      unsigned int w2;