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/*****************************************************************************
* parse.c: SPU parser
*****************************************************************************
* Copyright (C) 2000-2001, 2005, 2006 VLC authors and VideoLAN
* $Id$
*
* Authors: Sam Hocevar <sam@zoy.org>
* Laurent Aimar <fenrir@via.ecp.fr>
* Gildas Bazin <gbazin@videolan.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <vlc_common.h>
#include <vlc_codec.h>
#include <vlc_input.h>
#include "spudec.h"
/*****************************************************************************
* Local prototypes.
*****************************************************************************/
typedef struct
{
int i_width;
int i_height;
int i_x;
int i_y;
} spu_properties_t;
typedef struct
{
int pi_offset[2]; /* byte offsets to data */
uint16_t *p_data;
/* Color information */
bool b_palette;
uint8_t pi_alpha[4];
uint8_t pi_yuv[4][3];
/* Auto crop fullscreen subtitles */
bool b_auto_crop;
int i_y_top_offset;
int i_y_bottom_offset;
} subpicture_data_t;
static int ParseControlSeq( decoder_t *, subpicture_t *, subpicture_data_t *,
spu_properties_t *, mtime_t i_pts );
static int ParseRLE ( decoder_t *, subpicture_data_t *,
const spu_properties_t * );
static void Render ( decoder_t *, subpicture_t *, subpicture_data_t *,
const spu_properties_t * );
/*****************************************************************************
* AddNibble: read a nibble from a source packet and add it to our integer.
*****************************************************************************/
static inline unsigned int AddNibble( unsigned int i_code,
const uint8_t *p_src, unsigned int *pi_index )
{
if( *pi_index & 0x1 )
{
return( i_code << 4 | ( p_src[(*pi_index)++ >> 1] & 0xf ) );
}
else
{
return( i_code << 4 | p_src[(*pi_index)++ >> 1] >> 4 );
}
}
/*****************************************************************************
* 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.
*****************************************************************************/
subpicture_t * ParsePacket( decoder_t *p_dec )
{
decoder_sys_t *p_sys = p_dec->p_sys;
subpicture_t *p_spu;
subpicture_data_t spu_data;
spu_properties_t spu_properties;
/* Allocate the subpicture internal data. */
p_spu = decoder_NewSubpicture( p_dec, NULL );
if( !p_spu ) return NULL;
p_spu->i_original_picture_width =
p_dec->fmt_in.subs.spu.i_original_frame_width;
p_spu->i_original_picture_height =
p_dec->fmt_in.subs.spu.i_original_frame_height;
/* Getting the control part */
if( ParseControlSeq( p_dec, p_spu, &spu_data, &spu_properties, p_sys->i_pts ) )
{
/* There was a parse error, delete the subpicture */
subpicture_Delete( p_spu );
return NULL;
}
/* 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.
*
* Rationale for the "p_spudec->i_rle_size * 4*sizeof(*spu_data.p_data)":
* one byte gaves two nibbles and may be used twice (once per field)
* generating 4 codes.
*/
spu_data.p_data = vlc_alloc( p_sys->i_rle_size, sizeof(*spu_data.p_data) * 2 * 2 );
/* We try to display it */
if( ParseRLE( p_dec, &spu_data, &spu_properties ) )
{
/* There was a parse error, delete the subpicture */
subpicture_Delete( p_spu );
free( spu_data.p_data );
return NULL;
}
#ifdef DEBUG_SPUDEC
msg_Dbg( p_dec, "total size: 0x%x, RLE offsets: 0x%x 0x%x",
p_sys->i_spu_size,
spu_data.pi_offset[0], spu_data.pi_offset[1] );
#endif
Render( p_dec, p_spu, &spu_data, &spu_properties );
free( spu_data.p_data );
return p_spu;
}
/*****************************************************************************
* ParseControlSeq: 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 ParseControlSeq( decoder_t *p_dec, subpicture_t *p_spu,
subpicture_data_t *p_spu_data, spu_properties_t *p_spu_properties, mtime_t i_pts )
{
decoder_sys_t *p_sys = p_dec->p_sys;
/* Our current index in the SPU packet */
unsigned int i_index;
/* The next start-of-control-sequence index and the previous one */
unsigned int i_next_seq = 0, i_cur_seq = 0;
/* Command and date */
uint8_t i_command = SPU_CMD_END;
mtime_t date = 0;
bool b_cmd_offset = false;
bool b_cmd_alpha = false;
subpicture_data_t spu_data_cmd;
if( !p_spu || !p_spu_data )
return VLC_EGENERIC;
/* Create working space for spu data */
memset( &spu_data_cmd, 0, sizeof(spu_data_cmd) );
spu_data_cmd.pi_offset[0] = -1;
spu_data_cmd.pi_offset[1] = -1;
spu_data_cmd.p_data = NULL;
spu_data_cmd.b_palette = false;
spu_data_cmd.b_auto_crop = false;
spu_data_cmd.i_y_top_offset = 0;
spu_data_cmd.i_y_bottom_offset = 0;
spu_data_cmd.pi_alpha[0] = 0x00;
spu_data_cmd.pi_alpha[1] = 0x0f;
spu_data_cmd.pi_alpha[2] = 0x0f;
spu_data_cmd.pi_alpha[3] = 0x0f;
/* Initialize the structure */
p_spu->i_start = p_spu->i_stop = 0;
p_spu->b_ephemer = false;
memset( p_spu_properties, 0, sizeof(*p_spu_properties) );
/* */
*p_spu_data = spu_data_cmd;
for( i_index = 4 + p_sys->i_rle_size; i_index < p_sys->i_spu_size ; )
{
/* If we just read a command sequence, read the next one;
* otherwise, go on with the commands of the current sequence. */
if( i_command == SPU_CMD_END )
{
if( i_index + 4 > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU command sequence" );
return VLC_EGENERIC;
}
/* */
b_cmd_offset = false;
b_cmd_alpha = false;
/* Get the control sequence date */
date = (mtime_t)GetWBE( &p_sys->buffer[i_index] ) * 11000;
/* Next offset */
i_cur_seq = i_index;
i_next_seq = GetWBE( &p_sys->buffer[i_index+2] );
if( i_next_seq > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU next command sequence" );
return VLC_EGENERIC;
}
/* Skip what we just read */
i_index += 4;
}
i_command = p_sys->buffer[i_index];
switch( i_command )
{
case SPU_CMD_FORCE_DISPLAY: /* 00 (force displaying) */
p_spu->i_start = i_pts + date;
p_spu->b_ephemer = true;
/* ignores picture date as display start time
* works around non displayable (offset by few ms)
* spu menu over still frame in SPU_Select */
p_spu->b_subtitle = false;
i_index += 1;
break;
/* Convert the dates in seconds to PTS values */
case SPU_CMD_START_DISPLAY: /* 01 (start displaying) */
p_spu->i_start = i_pts + date;
i_index += 1;
break;
case SPU_CMD_STOP_DISPLAY: /* 02 (stop displaying) */
p_spu->i_stop = i_pts + date;
i_index += 1;
break;
case SPU_CMD_SET_PALETTE:
/* 03xxxx (palette) */
if( i_index + 3 > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU command" );
return VLC_EGENERIC;
}
if( p_dec->fmt_in.subs.spu.palette[0] == SPU_PALETTE_DEFINED )
{
unsigned int idx[4];
int i;
spu_data_cmd.b_palette = true;
idx[0] = (p_sys->buffer[i_index+1]>>4)&0x0f;
idx[1] = (p_sys->buffer[i_index+1])&0x0f;
idx[2] = (p_sys->buffer[i_index+2]>>4)&0x0f;
idx[3] = (p_sys->buffer[i_index+2])&0x0f;
for( i = 0; i < 4 ; i++ )
{
uint32_t i_color = p_dec->fmt_in.subs.spu.palette[1+idx[i]];
/* FIXME: this job should be done sooner */
spu_data_cmd.pi_yuv[3-i][0] = (i_color>>16) & 0xff;
spu_data_cmd.pi_yuv[3-i][1] = (i_color>>0) & 0xff;
spu_data_cmd.pi_yuv[3-i][2] = (i_color>>8) & 0xff;
}
}
i_index += 3;
break;
case SPU_CMD_SET_ALPHACHANNEL: /* 04xxxx (alpha channel) */
if( i_index + 3 > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU command" );
return VLC_EGENERIC;
}
if(!p_sys->b_disabletrans)
{ /* If we want to use original transparency values */
b_cmd_alpha = true;
spu_data_cmd.pi_alpha[3] = (p_sys->buffer[i_index+1]>>4)&0x0f;
spu_data_cmd.pi_alpha[2] = (p_sys->buffer[i_index+1])&0x0f;
spu_data_cmd.pi_alpha[1] = (p_sys->buffer[i_index+2]>>4)&0x0f;
spu_data_cmd.pi_alpha[0] = (p_sys->buffer[i_index+2])&0x0f;
}
i_index += 3;
break;
case SPU_CMD_SET_COORDINATES: /* 05xxxyyyxxxyyy (coordinates) */
if( i_index + 7 > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU command" );
return VLC_EGENERIC;
}
p_spu_properties->i_x = (p_sys->buffer[i_index+1]<<4)|
((p_sys->buffer[i_index+2]>>4)&0x0f);
p_spu_properties->i_width = (((p_sys->buffer[i_index+2]&0x0f)<<8)|
p_sys->buffer[i_index+3]) - p_spu_properties->i_x + 1;
p_spu_properties->i_y = (p_sys->buffer[i_index+4]<<4)|
((p_sys->buffer[i_index+5]>>4)&0x0f);
p_spu_properties->i_height = (((p_sys->buffer[i_index+5]&0x0f)<<8)|
p_sys->buffer[i_index+6]) - p_spu_properties->i_y + 1;
/* Auto crop fullscreen subtitles */
if( p_spu_properties->i_height > 250 )
p_spu_data->b_auto_crop = true;
i_index += 7;
break;
case SPU_CMD_SET_OFFSETS: /* 06xxxxyyyy (byte offsets) */
if( i_index + 5 > p_sys->i_spu_size )
{
msg_Err( p_dec, "overflow in SPU command" );
return VLC_EGENERIC;
}
b_cmd_offset = true;
p_spu_data->pi_offset[0] = GetWBE(&p_sys->buffer[i_index+1]) - 4;
p_spu_data->pi_offset[1] = GetWBE(&p_sys->buffer[i_index+3]) - 4;
i_index += 5;
break;
case SPU_CMD_END: /* ff (end) */
if( b_cmd_offset )
{
/* It seems that palette and alpha from the block having
* the cmd offset have to be used
* XXX is it all ? */
p_spu_data->b_palette = spu_data_cmd.b_palette;
if( spu_data_cmd.b_palette )
memcpy( p_spu_data->pi_yuv, spu_data_cmd.pi_yuv, sizeof(spu_data_cmd.pi_yuv) );
if( b_cmd_alpha )
memcpy( p_spu_data->pi_alpha, spu_data_cmd.pi_alpha, sizeof(spu_data_cmd.pi_alpha) );
}
i_index += 1;
break;
default: /* xx (unknown command) */
msg_Warn( p_dec, "unknown SPU command 0x%.2x", i_command );
if( i_index + 1 < i_next_seq )
{
/* There is at least one other command sequence */
if( p_sys->buffer[i_next_seq - 1] == SPU_CMD_END )
{
/* This is consistent. Skip to that command sequence. */
i_index = i_next_seq;
}
else
{
/* There were other commands. */
msg_Warn( p_dec, "cannot recover, dropping subtitle" );
return VLC_EGENERIC;
}
}
else
{
/* We were in the last command sequence. Stop parsing by
* pretending we met an SPU_CMD_END command. */
i_command = SPU_CMD_END;
i_index++;
}
}
/* */
if( i_command == SPU_CMD_END && i_index != i_next_seq )
break;
}
/* Check that the next sequence index matches the current one */
if( i_next_seq != i_cur_seq )
{
msg_Err( p_dec, "index mismatch (0x%.4x != 0x%.4x)",
i_next_seq, i_cur_seq );
return VLC_EGENERIC;
}
if( i_index > p_sys->i_spu_size )
{
msg_Err( p_dec, "uh-oh, we went too far (0x%.4x > 0x%.4x)",
i_index, p_sys->i_spu_size );
return VLC_EGENERIC;
}
const int i_spu_size = p_sys->i_spu - 4;
if( p_spu_data->pi_offset[0] < 0 || p_spu_data->pi_offset[0] >= i_spu_size ||
p_spu_data->pi_offset[1] < 0 || p_spu_data->pi_offset[1] >= i_spu_size )
{
msg_Err( p_dec, "invalid offset values" );
return VLC_EGENERIC;
}
if( !p_spu->i_start )
{
msg_Err( p_dec, "no `start display' command" );
return VLC_EGENERIC;
}
if( p_spu->i_stop <= p_spu->i_start && !p_spu->b_ephemer )
{
/* This subtitle will live for 5 seconds or until the next subtitle */
p_spu->i_stop = p_spu->i_start + (mtime_t)500 * 11000;
p_spu->b_ephemer = true;
}
/* Get rid of padding bytes */
if( p_sys->i_spu_size > i_index + 1 )
{
/* Zero or one padding byte are quite usual
* More than one padding byte - this is very strange, but
* we can ignore them. */
msg_Warn( p_dec, "%i padding bytes, we usually get 0 or 1 of them",
p_sys->i_spu_size - i_index );
}
/* Successfully parsed ! */
return VLC_SUCCESS;
}
/*****************************************************************************
* 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( decoder_t *p_dec,
subpicture_data_t *p_spu_data,
const spu_properties_t *p_spu_properties )
{
decoder_sys_t *p_sys = p_dec->p_sys;
const unsigned int i_width = p_spu_properties->i_width;
const unsigned int i_height = p_spu_properties->i_height;
unsigned int i_x, i_y;
uint16_t *p_dest = p_spu_data->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;
/* Cropping */
bool b_empty_top = true;
unsigned int i_skipped_top = 0, i_skipped_bottom = 0;
unsigned int i_transparent_code = 0;
/* Colormap statistics */
int i_border = -1;
int stats[4]; stats[0] = stats[1] = stats[2] = stats[3] = 0;
pi_table[ 0 ] = p_spu_data->pi_offset[ 0 ] << 1;
pi_table[ 1 ] = p_spu_data->pi_offset[ 1 ] << 1;
for( i_y = 0 ; i_y < i_height ; i_y++ )
{
unsigned int i_code;
pi_offset = pi_table + i_id;
for( i_x = 0 ; i_x < i_width ; i_x += i_code >> 2 )
{
i_code = 0;
for( unsigned int i_min = 1; i_min <= 0x40 && i_code < i_min; i_min <<= 2 )
{
if( (*pi_offset >> 1) >= p_sys->i_spu_size )
{
msg_Err( p_dec, "out of bounds while reading rle" );
return VLC_EGENERIC;
}
i_code = AddNibble( i_code, &p_sys->buffer[4], pi_offset );
}
if( i_code < 0x0004 )
{
/* If the 14 first bits are set to 0, then it's a
* new line. We emulate it. */
i_code |= ( i_width - i_x ) << 2;
}
if( ( (i_code >> 2) + i_x + i_y * i_width ) > i_height * i_width )
{
msg_Err( p_dec, "out of bounds, %i at (%i,%i) is out of %ix%i",
i_code >> 2, i_x, i_y, i_width, i_height );
return VLC_EGENERIC;
}
/* Try to find the border color */
if( p_spu_data->pi_alpha[ i_code & 0x3 ] != 0x00 )
{
i_border = i_code & 0x3;
stats[i_border] += i_code >> 2;
}
/* Auto crop subtitles (a lot more optimized) */
if( p_spu_data->b_auto_crop )
{
if( !i_y )
{
/* We assume that if the first line is transparent, then
* it is using the palette index for the
* (background) transparent color */
if( (i_code >> 2) == i_width &&
p_spu_data->pi_alpha[ i_code & 0x3 ] == 0x00 )
{
i_transparent_code = i_code;
}
else
{
p_spu_data->b_auto_crop = false;
}
}
if( i_code == i_transparent_code )
{
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;
i_skipped_bottom++;
}
}
else
{
/* We got a valid code, store it */
*p_dest++ = i_code;
/* Valid code means no blank line */
b_empty_top = false;
i_skipped_bottom = 0;
}
}
else
{
*p_dest++ = i_code;
}
}
/* Check that we didn't go too far */
if( i_x > i_width )
{
msg_Err( p_dec, "i_x overflowed, %i > %i", i_x, i_width );
return VLC_EGENERIC;
}
/* 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 )
{
msg_Err( p_dec, "padding bytes found in RLE sequence" );
msg_Err( p_dec, "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 VLC_EGENERIC;
}
#ifdef DEBUG_SPUDEC
msg_Dbg( p_dec, "valid subtitle, size: %ix%i, position: %i,%i",
p_spu->i_width, p_spu->i_height, p_spu->i_x, p_spu->i_y );
#endif
/* Crop if necessary */
if( i_skipped_top || i_skipped_bottom )
{
#ifdef DEBUG_SPUDEC
int i_y = p_spu->i_y + i_skipped_top;
int i_height = p_spu->i_height - (i_skipped_top + i_skipped_bottom);
#endif
p_spu_data->i_y_top_offset = i_skipped_top;
p_spu_data->i_y_bottom_offset = i_skipped_bottom;
#ifdef DEBUG_SPUDEC
msg_Dbg( p_dec, "cropped to: %ix%i, position: %i,%i",
p_spu->i_width, i_height, p_spu->i_x, i_y );
#endif
}
/* Handle color if no palette was found */
if( !p_spu_data->b_palette )
{
int i, i_inner = -1, i_shade = -1;
/* Set the border color */
if( i_border != -1 )
{
p_spu_data->pi_yuv[i_border][0] = 0x00;
p_spu_data->pi_yuv[i_border][1] = 0x80;
p_spu_data->pi_yuv[i_border][2] = 0x80;
stats[i_border] = 0;
}
/* Find the inner colors */
for( i = 0 ; i < 4 && i_inner == -1 ; i++ )
{
if( stats[i] )
{
i_inner = i;
}
}
for( ; i < 4 && i_shade == -1 ; i++ )
{
if( stats[i] )
{
if( stats[i] > stats[i_inner] )
{
i_shade = i_inner;
i_inner = i;
}
else
{
i_shade = i;
}
}
}
/* Set the inner color */
if( i_inner != -1 )
{
p_spu_data->pi_yuv[i_inner][0] = 0xff;
p_spu_data->pi_yuv[i_inner][1] = 0x80;
p_spu_data->pi_yuv[i_inner][2] = 0x80;
}
/* Set the anti-aliasing color */
if( i_shade != -1 )
{
p_spu_data->pi_yuv[i_shade][0] = 0x80;
p_spu_data->pi_yuv[i_shade][1] = 0x80;
p_spu_data->pi_yuv[i_shade][2] = 0x80;
}
#ifdef DEBUG_SPUDEC
msg_Dbg( p_dec, "using custom palette (border %i, inner %i, shade %i)",
i_border, i_inner, i_shade );
#endif
}
return VLC_SUCCESS;
}
static void Render( decoder_t *p_dec, subpicture_t *p_spu,
subpicture_data_t *p_spu_data,
const spu_properties_t *p_spu_properties )
{
uint8_t *p_p;
int i_x, i_y, i_len, i_color, i_pitch;
const uint16_t *p_source = p_spu_data->p_data;
video_format_t fmt;
video_palette_t palette;
/* Create a new subpicture region */
video_format_Init( &fmt, VLC_CODEC_YUVP );
fmt.i_sar_num = 0; /* 0 means use aspect ratio of background video */
fmt.i_sar_den = 1;
fmt.i_width = fmt.i_visible_width = p_spu_properties->i_width;
fmt.i_height = fmt.i_visible_height = p_spu_properties->i_height -
p_spu_data->i_y_top_offset - p_spu_data->i_y_bottom_offset;
fmt.i_x_offset = fmt.i_y_offset = 0;
fmt.p_palette = &palette;
fmt.p_palette->i_entries = 4;
for( i_x = 0; i_x < fmt.p_palette->i_entries; i_x++ )
{
fmt.p_palette->palette[i_x][0] = p_spu_data->pi_yuv[i_x][0];
fmt.p_palette->palette[i_x][1] = p_spu_data->pi_yuv[i_x][1];
fmt.p_palette->palette[i_x][2] = p_spu_data->pi_yuv[i_x][2];
fmt.p_palette->palette[i_x][3] = p_spu_data->pi_alpha[i_x] * 0x11;
}
p_spu->p_region = subpicture_region_New( &fmt );
if( !p_spu->p_region )
{
fmt.p_palette = NULL;
video_format_Clean( &fmt );
msg_Err( p_dec, "cannot allocate SPU region" );
return;
}
p_spu->p_region->i_x = p_spu_properties->i_x;
p_spu->p_region->i_y = p_spu_properties->i_y + p_spu_data->i_y_top_offset;
p_p = p_spu->p_region->p_picture->p->p_pixels;
i_pitch = p_spu->p_region->p_picture->p->i_pitch;
/* Draw until we reach the bottom of the subtitle */
for( i_y = 0; i_y < (int)fmt.i_height * i_pitch; i_y += i_pitch )
{
/* Draw until we reach the end of the line */
for( i_x = 0 ; i_x < (int)fmt.i_width; i_x += i_len )
{
/* Get the RLE part, then draw the line */
i_color = *p_source & 0x3;
i_len = *p_source++ >> 2;
memset( p_p + i_x + i_y, i_color, i_len );
}
}
fmt.p_palette = NULL;
video_format_Clean( &fmt );
}