]> git.sesse.net Git - vlc/blobdiff - src/spu_decoder/spu_decoder.c
* DirectX plugin by Gildas Bazin <gbazin@netcourrier.com>.
[vlc] / src / spu_decoder / spu_decoder.c
index 5f276966d231345f36c36bbe2d1395d920006d30..1d02bb0dd2f44ad6487730f24a0a06a1ff3d28c9 100644 (file)
 /*****************************************************************************
  * spu_decoder.c : spu decoder thread
- * (c)2000 VideoLAN
+ *****************************************************************************
+ * Copyright (C) 2000 VideoLAN
+ * $Id: spu_decoder.c,v 1.47 2001/06/02 01:09:03 sam Exp $
+ *
+ * Authors: Samuel Hocevar <sam@zoy.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, USA.
  *****************************************************************************/
 
-/* repompĂ© sur video_decoder.c
- * FIXME: passer en terminate/destroy avec les signaux supplĂ©mentaires ?? */
-
 /*****************************************************************************
  * Preamble
  *****************************************************************************/
-//#include "vlc.h"
+#include "defs.h"
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>                                              /* getpid() */
+#endif
 
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <string.h>
-#include <sys/uio.h>
+#ifdef WIN32                   /* getpid() for win32 is located in process.h */
+#include <process.h>
+#endif
+
+#include <stdlib.h>                                      /* malloc(), free() */
+#include <string.h>                                    /* memcpy(), memset() */
 
 #include "config.h"
 #include "common.h"
+#include "threads.h"
 #include "mtime.h"
-#include "vlc_thread.h"
 
 #include "intf_msg.h"
-#include "debug.h"                 /* XXX?? temporaire, requis par netlist.h */
 
-#include "input.h"
-#include "input_netlist.h"
-#include "decoder_fifo.h"
+#include "stream_control.h"
+#include "input_ext-dec.h"
+
+#include "video.h"
+#include "video_output.h"
 
 #include "spu_decoder.h"
 
-/*
+/*****************************************************************************
  * Local prototypes
- */
-static int      InitThread          ( spudec_thread_t *p_spudec );
-static void     RunThread           ( spudec_thread_t *p_spudec );
-static void     ErrorThread         ( spudec_thread_t *p_spudec );
-static void     EndThread           ( spudec_thread_t *p_spudec );
+ *****************************************************************************/
+static int  InitThread  ( spudec_thread_t * );
+static void RunThread   ( spudec_thread_t * );
+static void ErrorThread ( spudec_thread_t * );
+static void EndThread   ( spudec_thread_t * );
+
+static int  SyncPacket           ( spudec_thread_t * );
+static void ParsePacket          ( spudec_thread_t * );
+static int  ParseControlSequences( spudec_thread_t *, subpicture_t * );
+static int  ParseRLE             ( spudec_thread_t *, subpicture_t *, u8 * );
 
 /*****************************************************************************
  * spudec_CreateThread: create a spu decoder thread
  *****************************************************************************/
-spudec_thread_t * spudec_CreateThread( input_thread_t * p_input )
+vlc_thread_t spudec_CreateThread( vdec_config_t * p_config )
 {
     spudec_thread_t *     p_spudec;
 
-    intf_DbgMsg("spudec debug: creating spu decoder thread\n");
-
     /* Allocate the memory needed to store the thread's structure */
-    if ( (p_spudec = (spudec_thread_t *)malloc( sizeof(spudec_thread_t) )) == NULL )
+    p_spudec = (spudec_thread_t *)malloc( sizeof(spudec_thread_t) );
+
+    if ( p_spudec == NULL )
     {
-        intf_ErrMsg("spudec error: not enough memory for spudec_CreateThread() to create the new thread\n");
-        return( NULL );
+        intf_ErrMsg( "spudec error: not enough memory "
+                     "for spudec_CreateThread() to create the new thread" );
+        return( 0 );
     }
 
     /*
      * Initialize the thread properties
      */
-    p_spudec->b_die = 0;
-    p_spudec->b_error = 0;
+    p_spudec->p_config = p_config;
 
-    /*
-     * Initialize the input properties
-     */
-    /* Initialize the decoder fifo's data lock and conditional variable and set
-     * its buffer as empty */
-    vlc_mutex_init( &p_spudec->fifo.data_lock );
-    vlc_cond_init( &p_spudec->fifo.data_wait );
-    p_spudec->fifo.i_start = 0;
-    p_spudec->fifo.i_end = 0;
-    /* Initialize the bit stream structure */
-    p_spudec->bit_stream.p_input = p_input;
-    p_spudec->bit_stream.p_decoder_fifo = &p_spudec->fifo;
-    p_spudec->bit_stream.fifo.buffer = 0;
-    p_spudec->bit_stream.fifo.i_available = 0;
+    p_spudec->p_fifo = p_config->decoder_config.p_decoder_fifo;
+
+    /* Spawn a video output if there is none */
+    vlc_mutex_lock( &p_vout_bank->lock );
+
+    if( p_vout_bank->i_count == 0 )
+    {
+        intf_WarnMsg( 1, "spudec: no vout present, spawning one" );
+
+        p_spudec->p_vout = vout_CreateThread( NULL );
+
+        /* Everything failed */
+        if( p_spudec->p_vout == NULL )
+        {
+            intf_Msg( "spudec: can't open vout, aborting" );
+            vlc_mutex_unlock( &p_vout_bank->lock );
+            free( p_spudec );
+
+            return 0;
+        }
+
+        p_vout_bank->pp_vout[ p_vout_bank->i_count ] = p_spudec->p_vout;
+        p_vout_bank->i_count++;
+    }
+    else
+    {
+        /* Take the first video output FIXME: take the best one */
+        p_spudec->p_vout = p_vout_bank->pp_vout[ 0 ];
+    }
+
+    vlc_mutex_unlock( &p_vout_bank->lock );
 
     /* Spawn the spu decoder thread */
     if ( vlc_thread_create(&p_spudec->thread_id, "spu decoder",
          (vlc_thread_func_t)RunThread, (void *)p_spudec) )
     {
-        intf_ErrMsg("spudec error: can't spawn spu decoder thread\n");
+        intf_ErrMsg( "spudec error: can't spawn spu decoder thread" );
         free( p_spudec );
-        return( NULL );
+        return 0;
     }
 
-    intf_DbgMsg("spudec debug: spu decoder thread (%p) created\n", p_spudec);
-    return( p_spudec );
-}
-
-/*****************************************************************************
- * spudec_DestroyThread: destroy a spu decoder thread
- *****************************************************************************
- * Destroy and terminate thread. This function will return 0 if the thread could
- * be destroyed, and non 0 else. The last case probably means that the thread
- * was still active, and another try may succeed.
- *****************************************************************************/
-void spudec_DestroyThread( spudec_thread_t *p_spudec )
-{
-    intf_DbgMsg("spudec debug: requesting termination of spu decoder thread %p\n", p_spudec);
-
-    /* Ask thread to kill itself */
-    p_spudec->b_die = 1;
-
-    /* Warn the decoder that we're quitting */
-    vlc_mutex_lock( &p_spudec->fifo.data_lock );
-    vlc_cond_signal( &p_spudec->fifo.data_wait );
-    vlc_mutex_unlock( &p_spudec->fifo.data_lock );
-
-    /* Waiting for the decoder thread to exit */
-    /* Remove this as soon as the "status" flag is implemented */
-    vlc_thread_join( p_spudec->thread_id );
+    return( p_spudec->thread_id );
 }
 
 /* following functions are local */
@@ -125,78 +142,51 @@ void spudec_DestroyThread( spudec_thread_t *p_spudec )
  *****************************************************************************/
 static int InitThread( spudec_thread_t *p_spudec )
 {
-    intf_DbgMsg("spudec debug: initializing spu decoder thread %p\n", p_spudec);
-
-    /* Our first job is to initialize the bit stream structure with the
-     * beginning of the input stream */
-    vlc_mutex_lock( &p_spudec->fifo.data_lock );
-    while ( DECODER_FIFO_ISEMPTY(p_spudec->fifo) )
-    {
-        if ( p_spudec->b_die )
-        {
-            vlc_mutex_unlock( &p_spudec->fifo.data_lock );
-            return( 1 );
-        }
-        vlc_cond_wait( &p_spudec->fifo.data_wait, &p_spudec->fifo.data_lock );
-    }
-
-    p_spudec->bit_stream.p_ts = DECODER_FIFO_START( p_spudec->fifo )->p_first_ts;
-    p_spudec->bit_stream.p_byte = p_spudec->bit_stream.p_ts->buffer + p_spudec->bit_stream.p_ts->i_payload_start;
-    p_spudec->bit_stream.p_end = p_spudec->bit_stream.p_ts->buffer + p_spudec->bit_stream.p_ts->i_payload_end;
-    vlc_mutex_unlock( &p_spudec->fifo.data_lock );
+    p_spudec->p_config->decoder_config.pf_init_bit_stream(
+            &p_spudec->bit_stream,
+            p_spudec->p_config->decoder_config.p_decoder_fifo, NULL, NULL );
 
     /* Mark thread as running and return */
-    intf_DbgMsg( "spudec debug: InitThread(%p) succeeded\n", p_spudec );
     return( 0 );
 }
 
 /*****************************************************************************
  * RunThread: spu decoder thread
  *****************************************************************************
- * spu decoder thread. This function does only return when the thread is
+ * spu decoder thread. This function only returns when the thread is
  * terminated.
  *****************************************************************************/
 static void RunThread( spudec_thread_t *p_spudec )
 {
-    intf_DbgMsg("spudec debug: running spu decoder thread (%p) (pid == %i)\n",
-        p_spudec, getpid());
+    intf_WarnMsg( 3, "spudec: spu decoder thread %i spawned", getpid() );
 
     /*
      * Initialize thread and free configuration
      */
-    p_spudec->b_error = InitThread( p_spudec );
-
-    p_spudec->b_run = 1;
+    p_spudec->p_fifo->b_error = InitThread( p_spudec );
 
     /*
      * Main loop - it is not executed if an error occured during
      * initialization
      */
-    vlc_mutex_lock( &p_spudec->fifo.data_lock );
-    while( (!p_spudec->b_die) && (!p_spudec->b_error) )
+    while( (!p_spudec->p_fifo->b_die) && (!p_spudec->p_fifo->b_error) )
     {
-        /* Trash all received PES packets */
-        while( !DECODER_FIFO_ISEMPTY(p_spudec->fifo) )
+        if( !SyncPacket( p_spudec ) )
         {
-            input_NetlistFreePES( p_spudec->bit_stream.p_input, DECODER_FIFO_START(p_spudec->fifo) );
-            DECODER_FIFO_INCSTART( p_spudec->fifo );
+            ParsePacket( p_spudec );
         }
-        /* Waiting for the input thread to put new PES packets in the fifo */
-        vlc_cond_wait( &p_spudec->fifo.data_wait, &p_spudec->fifo.data_lock );
     }
-    vlc_mutex_unlock( &p_spudec->fifo.data_lock );
 
     /*
      * Error loop
      */
-    if( p_spudec->b_error )
+    if( p_spudec->p_fifo->b_error )
     {
         ErrorThread( p_spudec );
     }
 
-    p_spudec->b_run = 0;
-
     /* End of thread */
+    intf_WarnMsg( 3, "spudec: destroying spu decoder thread %i", getpid() );
     EndThread( p_spudec );
 }
 
@@ -211,35 +201,518 @@ static void ErrorThread( spudec_thread_t *p_spudec )
 {
     /* We take the lock, because we are going to read/write the start/end
      * indexes of the decoder fifo */
-    vlc_mutex_lock( &p_spudec->fifo.data_lock );
+    vlc_mutex_lock( &p_spudec->p_fifo->data_lock );
 
     /* Wait until a `die' order is sent */
-    while( !p_spudec->b_die )
+    while( !p_spudec->p_fifo->b_die )
     {
         /* Trash all received PES packets */
-        while( !DECODER_FIFO_ISEMPTY(p_spudec->fifo) )
+        while( !DECODER_FIFO_ISEMPTY(*p_spudec->p_fifo) )
         {
-            input_NetlistFreePES( p_spudec->bit_stream.p_input, DECODER_FIFO_START(p_spudec->fifo) );
-            DECODER_FIFO_INCSTART( p_spudec->fifo );
+            p_spudec->p_fifo->pf_delete_pes( p_spudec->p_fifo->p_packets_mgt,
+                    DECODER_FIFO_START(*p_spudec->p_fifo) );
+            DECODER_FIFO_INCSTART( *p_spudec->p_fifo );
         }
 
         /* Waiting for the input thread to put new PES packets in the fifo */
-        vlc_cond_wait( &p_spudec->fifo.data_wait, &p_spudec->fifo.data_lock );
+        vlc_cond_wait( &p_spudec->p_fifo->data_wait,
+                       &p_spudec->p_fifo->data_lock );
     }
 
     /* We can release the lock before leaving */
-    vlc_mutex_unlock( &p_spudec->fifo.data_lock );
+    vlc_mutex_unlock( &p_spudec->p_fifo->data_lock );
 }
 
 /*****************************************************************************
  * EndThread: thread destruction
  *****************************************************************************
- * This function is called when the thread ends after a sucessfull
+ * This function is called when the thread ends after a sucessful
  * initialization.
  *****************************************************************************/
 static void EndThread( spudec_thread_t *p_spudec )
 {
-    intf_DbgMsg( "spudec debug: destroying spu decoder thread %p\n", p_spudec );
+    free( p_spudec->p_config );
     free( p_spudec );
-    intf_DbgMsg( "spudec debug: spu decoder thread %p destroyed\n", p_spudec);
 }
+
+/*****************************************************************************
+ * SyncPacket: get in sync with the stream
+ *****************************************************************************
+ * This function makes a few sanity checks and returns 0 if it looks like we
+ * are at the beginning of a subpicture packet.
+ *****************************************************************************/
+static int SyncPacket( spudec_thread_t *p_spudec )
+{
+    /* Re-align the buffer on an 8-bit boundary */
+    RealignBits( &p_spudec->bit_stream );
+
+    /* The total SPU packet size, often bigger than a PS packet */
+    p_spudec->i_spu_size = GetBits( &p_spudec->bit_stream, 16 );
+
+    /* The RLE stuff size (remove 4 because we just read 32 bits) */
+    p_spudec->i_rle_size = ShowBits( &p_spudec->bit_stream, 16 ) - 4;
+
+    /* If the values we got are a bit strange, skip packet */
+    if( !p_spudec->i_spu_size
+         || ( p_spudec->i_rle_size >= p_spudec->i_spu_size ) )
+    {
+        return( 1 );
+    }
+
+    RemoveBits( &p_spudec->bit_stream, 16 );
+
+    return( 0 );
+}
+
+/*****************************************************************************
+ * ParsePacket: parse an SPU packet and send it to the video output
+ *****************************************************************************
+ * This function parses the SPU packet and, if valid, sends it to the
+ * video output.
+ *****************************************************************************/
+static void ParsePacket( spudec_thread_t *p_spudec )
+{
+    subpicture_t * p_spu;
+    u8           * p_src;
+    unsigned int   i_offset;
+
+    intf_WarnMsg( 3, "spudec: trying to gather a 0x%.2x long subtitle",
+                  p_spudec->i_spu_size );
+
+    /* We cannot display a subpicture with no date */
+    if( DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts == 0 )
+    {
+        intf_WarnMsg( 3, "spudec error: subtitle without a date" );
+        return;
+    }
+
+    /* Allocate the subpicture internal data. */
+    p_spu = vout_CreateSubPicture( p_spudec->p_vout, DVD_SUBPICTURE,
+                                   p_spudec->i_rle_size * 4 );
+    /* Rationale for the "p_spudec->i_rle_size * 4": we are going to
+     * expand the RLE stuff so that we won't need to read nibbles later
+     * on. This will speed things up a lot. Plus, we'll only need to do
+     * this stupid interlacing stuff once. */
+
+    if( p_spu == NULL )
+    {
+        return;
+    }
+
+    /* Get display time now. If we do it later, we may miss the PTS. */
+    p_spudec->i_pts = DECODER_FIFO_START(*p_spudec->p_fifo)->i_pts;
+
+    /* Allocate the temporary buffer we will parse */
+    p_src = malloc( p_spudec->i_rle_size );
+
+    if( p_src == NULL )
+    {
+        intf_ErrMsg( "spudec error: could not allocate p_src" );
+        vout_DestroySubPicture( p_spudec->p_vout, p_spu );
+        return;
+    }
+
+    /* Get RLE data */
+    for( i_offset = 0;
+         i_offset + SPU_CHUNK_SIZE < p_spudec->i_rle_size;
+         i_offset += SPU_CHUNK_SIZE )
+    {
+        GetChunk( &p_spudec->bit_stream, p_src + i_offset, SPU_CHUNK_SIZE );
+
+        if( p_spudec->p_fifo->b_die )
+        {
+            free( p_src );
+            vout_DestroySubPicture( p_spudec->p_vout, p_spu );
+            return;
+        }
+    }
+
+    GetChunk( &p_spudec->bit_stream, p_src + i_offset,
+              p_spudec->i_rle_size - i_offset );
+
+#if 0
+    /* Dump the subtitle info */
+    intf_WarnHexDump( 5, p_spu->p_data, p_spudec->i_rle_size );
+#endif
+
+    /* Getting the control part */
+    if( p_spudec->p_fifo->b_die || ParseControlSequences( p_spudec, p_spu ) )
+    {
+        /* There was a parse error, delete the subpicture */
+        free( p_src );
+        vout_DestroySubPicture( p_spudec->p_vout, p_spu );
+        return;
+    }
+
+    if( ParseRLE( p_spudec, p_spu, p_src ) )
+    {
+        /* There was a parse error, delete the subpicture */
+        free( p_src );
+        vout_DestroySubPicture( p_spudec->p_vout, p_spu );
+        return;
+    }
+
+    intf_WarnMsg( 3, "spudec: total size: 0x%x, RLE offsets: 0x%x 0x%x",
+                  p_spudec->i_spu_size,
+                  p_spu->type.spu.i_offset[0], p_spu->type.spu.i_offset[1] );
+
+    /* SPU is finished - we can ask the video output to display it */
+    vout_DisplaySubPicture( p_spudec->p_vout, p_spu );
+
+    /* Clean up */
+    free( p_src );
+}
+
+/*****************************************************************************
+ * ParseControlSequences: parse all SPU control sequences
+ *****************************************************************************
+ * This is the most important part in SPU decoding. We get dates, palette
+ * information, coordinates, and so on. For more information on the
+ * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
+ *****************************************************************************/
+static int ParseControlSequences( spudec_thread_t *p_spudec,
+                                  subpicture_t * p_spu )
+{
+    /* Our current index in the SPU packet */
+    int i_index = p_spudec->i_rle_size + 4;
+
+    /* The next start-of-control-sequence index and the previous one */
+    int i_next_seq, i_cur_seq;
+
+    /* Command time and date */
+    u8  i_command;
+    int i_date;
+
+    /* XXX: temporary variables */
+    boolean_t b_force_display = 0;
+
+    /* Initialize the structure */
+    p_spu->i_start = p_spu->i_stop = 0;
+    p_spu->b_ephemer = 0;
+
+    do
+    {
+        /* Get the control sequence date */
+        i_date = GetBits( &p_spudec->bit_stream, 16 );
+        /* Next offset */
+        i_cur_seq = i_index;
+        i_next_seq = GetBits( &p_spudec->bit_stream, 16 );
+        /* Skip what we just read */
+        i_index += 4;
+        do
+        {
+            i_command = GetBits( &p_spudec->bit_stream, 8 );
+            i_index++;
+            switch( i_command )
+            {
+                case SPU_CMD_FORCE_DISPLAY:
+
+                    /* 00 (force displaying) */
+                    p_spu->i_start = p_spudec->i_pts + ( i_date * 11000 );
+                    b_force_display = 1;
+                    break;
+                /* Convert the dates in seconds to PTS values */
+                case SPU_CMD_START_DISPLAY:
+                    /* 01 (start displaying) */
+                    p_spu->i_start = p_spudec->i_pts + ( i_date * 11000 );
+                    break;
+                case SPU_CMD_STOP_DISPLAY:
+                    /* 02 (stop displaying) */
+                    p_spu->i_stop = p_spudec->i_pts + ( i_date * 11000 );
+                    break;
+                case SPU_CMD_SET_PALETTE:
+                    /* 03xxxx (palette) - trashed */
+                    RemoveBits( &p_spudec->bit_stream, 16 );
+                    i_index += 2;
+                    break;
+                case SPU_CMD_SET_ALPHACHANNEL:
+                    /* 04xxxx (alpha channel) - trashed */
+                    RemoveBits( &p_spudec->bit_stream, 16 );
+                    i_index += 2;
+                    break;
+                case SPU_CMD_SET_COORDINATES:
+                    /* 05xxxyyyxxxyyy (coordinates) */
+                    p_spu->i_x = GetBits( &p_spudec->bit_stream, 12 );
+                    p_spu->i_width = GetBits( &p_spudec->bit_stream, 12 )
+                                      - p_spu->i_x + 1;
+                    p_spu->i_y = GetBits( &p_spudec->bit_stream, 12 );
+                    p_spu->i_height = GetBits( &p_spudec->bit_stream, 12 )
+                                       - p_spu->i_y + 1;
+                    i_index += 6;
+                    break;
+                case SPU_CMD_SET_OFFSETS:
+                    /* 06xxxxyyyy (byte offsets) */
+                    p_spu->type.spu.i_offset[0] =
+                        GetBits( &p_spudec->bit_stream, 16 ) - 4;
+                    p_spu->type.spu.i_offset[1] =
+                        GetBits( &p_spudec->bit_stream, 16 ) - 4;
+                    i_index += 4;
+                    break;
+                case SPU_CMD_END:
+                    /* ff (end) */
+                    break;
+                default:
+                    /* xx (unknown command) */
+                    intf_ErrMsg( "spudec error: unknown command 0x%.2x",
+                                 i_command );
+                    return( 1 );
+            }
+
+        } while( i_command != SPU_CMD_END );
+
+    } while( i_index == i_next_seq );
+
+    /* Check that the next sequence index matches the current one */
+    if( i_next_seq != i_cur_seq )
+    {
+        intf_ErrMsg( "spudec error: index mismatch (0x%.4x != 0x%.4x)",
+                     i_next_seq, i_cur_seq );
+        return( 1 );
+    }
+
+    if( i_index > p_spudec->i_spu_size )
+    {
+        intf_ErrMsg( "spudec error: uh-oh, we went too far (0x%.4x > 0x%.4x)",
+                     i_index, p_spudec->i_spu_size );
+        return( 1 );
+    }
+
+    if( !p_spu->i_start )
+    {
+        intf_ErrMsg( "spudec error: no `start display' command" );
+    }
+
+    if( !p_spu->i_stop )
+    {
+        /* This subtitle will live for 5 seconds or until the next subtitle */
+        p_spu->i_stop = p_spu->i_start + 500 * 11000;
+        p_spu->b_ephemer = 1;
+    }
+
+    /* Get rid of padding bytes */
+    switch( p_spudec->i_spu_size - i_index )
+    {
+        /* Zero or one padding byte, quite usual */
+        case 1:
+            RemoveBits( &p_spudec->bit_stream, 8 );
+            i_index++;
+        case 0:
+            break;
+
+        /* More than one padding byte - this is very strange, but
+         * we can deal with it */
+        default:
+            intf_WarnMsg( 2, "spudec warning: %i padding bytes, we usually "
+                             "get 1 or none",
+                          p_spudec->i_spu_size - i_index );
+
+            while( i_index < p_spudec->i_spu_size )
+            {
+                RemoveBits( &p_spudec->bit_stream, 8 );
+                i_index++;
+            }
+
+            break;
+    }
+
+    if( b_force_display )
+    {
+        intf_ErrMsg( "spudec: \"force display\" command" );
+        intf_ErrMsg( "spudec: send mail to <sam@zoy.org> if you "
+                     "want to help debugging this" );
+    }
+
+    /* Successfully parsed ! */
+    return( 0 );
+}
+
+/*****************************************************************************
+ * ParseRLE: parse the RLE part of the subtitle
+ *****************************************************************************
+ * This part parses the subtitle graphical data and stores it in a more
+ * convenient structure for later decoding. For more information on the
+ * subtitles format, see http://sam.zoy.org/doc/dvd/subtitles/index.html
+ *****************************************************************************/
+static int ParseRLE( spudec_thread_t *p_spudec,
+                     subpicture_t * p_spu, u8 * p_src )
+{
+    unsigned int i_code;
+
+    unsigned int i_width = p_spu->i_width;
+    unsigned int i_height = p_spu->i_height;
+    unsigned int i_x, i_y;
+
+    u16 *p_dest = (u16 *)p_spu->p_data;
+
+    /* The subtitles are interlaced, we need two offsets */
+    unsigned int  i_id = 0;                   /* Start on the even SPU layer */
+    unsigned int  pi_table[ 2 ];
+    unsigned int *pi_offset;
+
+    boolean_t b_empty_top = 1,
+              b_empty_bottom = 0;
+    unsigned int i_skipped_top = 0,
+                 i_skipped_bottom = 0;
+
+    pi_table[ 0 ] = p_spu->type.spu.i_offset[ 0 ] << 1;
+    pi_table[ 1 ] = p_spu->type.spu.i_offset[ 1 ] << 1;
+
+    for( i_y = 0 ; i_y < i_height ; i_y++ )
+    {
+        pi_offset = pi_table + i_id;
+
+        for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
+        {
+            i_code = AddNibble( 0, p_src, pi_offset );
+
+            if( i_code < 0x04 )
+            {
+                i_code = AddNibble( i_code, p_src, pi_offset );
+
+                if( i_code < 0x10 )
+                {
+                    i_code = AddNibble( i_code, p_src, pi_offset );
+
+                    if( i_code < 0x040 )
+                    {
+                        i_code = AddNibble( i_code, p_src, pi_offset );
+
+                        if( i_code < 0x0100 )
+                        {
+                            /* If the 14 first bits are set to 0, then it's a
+                             * new line. We emulate it. */
+                            if( i_code < 0x0004 )
+                            {
+                                i_code |= ( i_width - i_x ) << 2;
+                            }
+                            else
+                            {
+                                /* We have a boo boo ! */
+                                intf_ErrMsg( "spudec error: unknown RLE code "
+                                             "0x%.4x", i_code );
+                                return( 1 );
+                            }
+                        }
+                    }
+                }
+            }
+
+            if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
+            {
+                intf_ErrMsg( "spudec error: out of bounds, %i at (%i,%i) is "
+                             "out of %ix%i",
+                             i_code >> 2, i_x, i_y, i_width, i_height);
+                return( 1 );
+            }
+
+            if( i_code == (i_width << 2) ) /* FIXME: we assume 0 is transp */
+            {
+                if( b_empty_top )
+                {
+                    /* This is a blank top line, we skip it */
+                    i_skipped_top++;
+                }
+                else
+                {
+                    /* We can't be sure the current lines will be skipped,
+                     * so we store the code just in case. */
+                    *p_dest++ = i_code;
+
+                    b_empty_bottom = 1;
+                    i_skipped_bottom++;
+                }
+            }
+            else
+            {
+                /* We got a valid code, store it */
+                *p_dest++ = i_code;
+
+                /* Valid code means no blank line */
+                b_empty_top = 0;
+                b_empty_bottom = 0;
+                i_skipped_bottom = 0;
+            }
+        }
+
+        /* Check that we didn't go too far */
+        if( i_x > i_width )
+        {
+            intf_ErrMsg( "spudec error: i_x overflowed, %i > %i",
+                         i_x, i_width );
+            return( 1 );
+        }
+
+        /* Byte-align the stream */
+        if( *pi_offset & 0x1 )
+        {
+            (*pi_offset)++;
+        }
+
+        /* Swap fields */
+        i_id = ~i_id & 0x1;
+    }
+
+    /* We shouldn't get any padding bytes */
+    if( i_y < i_height )
+    {
+        intf_ErrMsg( "spudec: padding bytes found in RLE sequence" );
+        intf_ErrMsg( "spudec: send mail to <sam@zoy.org> if you "
+                     "want to help debugging this" );
+
+        /* Skip them just in case */
+        while( i_y < i_height )
+       {
+            *p_dest++ = i_width << 2;
+            i_y++;
+       }
+
+        return( 1 );
+    }
+
+    intf_WarnMsg( 3, "spudec: valid subtitle, size: %ix%i, position: %i,%i",
+                  p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y );
+
+    /* Crop if necessary */
+    if( i_skipped_top || i_skipped_bottom )
+    {
+        p_spu->i_y += i_skipped_top;
+        p_spu->i_height -= i_skipped_top + i_skipped_bottom;
+
+        intf_WarnMsg( 3, "spudec: cropped to: %ix%i, position: %i,%i",
+                      p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y );
+    }
+
+    return( 0 );
+}
+