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/*****************************************************************************
* stl.c: EBU STL decoder
*****************************************************************************
* Copyright (C) 2010 Laurent Aimar
* $Id$
*
* Authors: Laurent Aimar <fenrir _AT_ videolan _DOT_ 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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <assert.h>
#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_codec.h>
#include <vlc_memory.h>
#include <vlc_charset.h>
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int Open (vlc_object_t *);
static void Close(vlc_object_t *);
vlc_module_begin()
set_description(N_("EBU STL subtitles decoder"))
set_category(CAT_INPUT)
set_subcategory(SUBCAT_INPUT_SCODEC)
set_capability("decoder", 10)
set_callbacks(Open, Close)
vlc_module_end()
/*****************************************************************************
* Local definitions/prototypes
*****************************************************************************/
#define GSI_BLOCK_SIZE 1024
typedef enum {
CCT_ISO_6937_2 = 0x3030, CCT_BEGIN = CCT_ISO_6937_2,
CCT_ISO_8859_5 = 0x3031,
CCT_ISO_8859_6 = 0x3032,
CCT_ISO_8859_7 = 0x3033,
CCT_ISO_8859_8 = 0x3034, CCT_END = CCT_ISO_8859_8
} cct_number_value_t;
typedef struct {
cct_number_value_t value;
const char *str;
} cct_number_t;
struct decoder_sys_t {
cct_number_value_t cct;
};
static cct_number_t cct_nums[] = { {CCT_ISO_6937_2, "ISO_6937-2"},
{CCT_ISO_8859_5, "ISO_8859-5"},
{CCT_ISO_8859_6, "ISO_8859-6"},
{CCT_ISO_8859_7, "ISO_8859-7"},
{CCT_ISO_8859_8, "ISO_8859-8"} };
static char *ParseText(uint8_t *data, int size, const char *charset)
{
char *text = strdup("");
int text_size = 0;
for (int i = 0; i < size; i++) {
uint8_t code = data[i];
if (code == 0x8f)
break;
char tmp[16] = "";
char *t = tmp;
if ((code >= 0x20 && code <= 0x7e) ||
(code >= 0xa0 && code <= 0xff) )
snprintf(tmp, sizeof(tmp), "%c", code);
#if 0
else if (code == 0x80)
snprintf(tmp, sizeof(tmp), "<i>");
else if (code == 0x81)
snprintf(tmp, sizeof(tmp), "</i>");
else if (code == 0x82)
snprintf(tmp, sizeof(tmp), "<u>");
else if (code == 0x83)
snprintf(tmp, sizeof(tmp), "</u>");
else if (code == 0x8a)
snprintf(tmp, sizeof(tmp), "\n");
#endif
else {
t = NULL;
}
if (!t)
continue;
size_t t_size = strlen(t);
text = realloc_or_free(text, t_size + text_size + 1);
if (!text)
continue;
memcpy(&text[text_size], t, t_size);
text_size += t_size;
text[text_size] = '\0';
}
return FromCharset(charset, text, text_size);
}
static subpicture_t *Decode(decoder_t *dec, block_t **block)
{
if (block == NULL || *block == NULL)
return NULL;
subpicture_t *sub = NULL;
block_t *b = *block; *block = NULL;
if (b->i_flags & (BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED))
goto exit;
if (b->i_buffer < 128)
goto exit;
int payload_size = (b->i_buffer / 128) * 112;
uint8_t *payload = malloc(payload_size);
if (!payload)
goto exit;
for (int i = 0; i < b->i_buffer / 128; i++)
memcpy(&payload[112 * i], &b->p_buffer[128 * i + 16], 112);
sub = decoder_NewSubpicture(dec, NULL);
if (!sub) {
free(payload);
goto exit;
}
sub->i_start = b->i_pts;
sub->i_stop = b->i_pts + b->i_length;
sub->b_ephemer = b->i_length == 0;
sub->b_absolute = false;
//sub->i_original_picture_width = 0;
//sub->i_original_picture_height = 0;
video_format_t fmt;
video_format_Init(&fmt, VLC_CODEC_TEXT);
sub->p_region = subpicture_region_New(&fmt);
video_format_Clean(&fmt);
if (sub->p_region) {
sub->p_region->psz_text = ParseText(payload,
payload_size,
cct_nums[dec->p_sys->cct - CCT_BEGIN].str);
sub->p_region->psz_html = NULL;
}
free(payload);
exit:
block_Release(b);
return sub;
}
static int ExtractCCT(const decoder_t *dec, cct_number_value_t *cct_number)
{
uint8_t *header = dec->fmt_in.p_extra;
if (!header) {
msg_Err(dec, "NULL EBU header (GSI block)\n");
return VLC_EGENERIC;
}
if (GSI_BLOCK_SIZE != dec->fmt_in.i_extra) {
msg_Err(dec, "EBU header is not in expected size (%d)\n", dec->fmt_in.i_extra);
return VLC_EGENERIC;
}
int cct = (header[12] << 8) | header[13];
if (CCT_BEGIN > cct || CCT_END < cct) {
msg_Err(dec, "EBU header contains illegal CCT (0x%x)\n", cct);
return VLC_EGENERIC;
}
*cct_number = cct;
return VLC_SUCCESS;
}
static int Open(vlc_object_t *object)
{
decoder_t *dec = (decoder_t*)object;
if (dec->fmt_in.i_codec != VLC_CODEC_EBU_STL)
return VLC_EGENERIC;
cct_number_value_t cct;
int rc = ExtractCCT(dec, &cct);
if (VLC_SUCCESS != rc)
return rc;
msg_Dbg(dec, "CCT=0x%x", cct);
decoder_sys_t *sys = malloc(sizeof(*sys));
if (!sys)
return VLC_ENOMEM;
sys->cct = cct;
dec->p_sys = sys;
dec->pf_decode_sub = Decode;
dec->fmt_out.i_cat = SPU_ES;
dec->fmt_out.i_codec = 0;
return VLC_SUCCESS;
}
static void Close(vlc_object_t *object)
{
decoder_t *dec = (decoder_t*)object;
decoder_sys_t *sys = dec->p_sys;
free(sys);
}