From cd734d3adc4e26c15c0e9ddecb5af8e39ccb3d37 Mon Sep 17 00:00:00 2001
From: Francois Cartegnie <fcvlcdev@free.fr>
Date: Wed, 24 Sep 2014 19:30:51 +0200
Subject: [PATCH] demux: mp4: add support for EIA-608 (fix #6775)
---
modules/demux/mp4/libmp4.h | 3 ++
modules/demux/mp4/mp4.c | 72 ++++++++++++++++++++++++++++++++++++--
2 files changed, 73 insertions(+), 2 deletions(-)
diff --git a/modules/demux/mp4/libmp4.h b/modules/demux/mp4/libmp4.h
index d8ec68446598..d4b68a31cef9 100644
--- a/modules/demux/mp4/libmp4.h
+++ b/modules/demux/mp4/libmp4.h
@@ -215,6 +215,9 @@
#define ATOM_tx3g VLC_FOURCC( 't', 'x', '3', 'g' )
#define ATOM_subp VLC_FOURCC( 's', 'u', 'b', 'p' )
#define ATOM_sbtl VLC_FOURCC( 's', 'b', 't', 'l' )
+#define ATOM_clcp VLC_FOURCC( 'c', 'l', 'c', 'p' )
+#define ATOM_c608 VLC_FOURCC( 'c', '6', '0', '8' )
+#define ATOM_c708 VLC_FOURCC( 'c', '7', '0', '8' )
#define ATOM_0xa9nam VLC_FOURCC( 0xa9, 'n', 'a', 'm' )
#define ATOM_0xa9aut VLC_FOURCC( 0xa9, 'a', 'u', 't' )
diff --git a/modules/demux/mp4/mp4.c b/modules/demux/mp4/mp4.c
index 655cb8cc1c3b..fa0819fbcd46 100644
--- a/modules/demux/mp4/mp4.c
+++ b/modules/demux/mp4/mp4.c
@@ -392,6 +392,62 @@ static void CreateTracksFromSmooBox( demux_t *p_demux )
}
}
+static block_t * MP4_EIA608_Convert( block_t * p_block )
+{
+ /* Rebuild codec data from encap */
+ size_t i_copied = 0;
+ size_t i_remaining = p_block->i_buffer;
+ uint32_t i_bytes = 0;
+ block_t *p_newblock;
+
+ if ( i_remaining < 10 ||
+ !(i_bytes = GetDWBE(p_block->p_buffer)) ||
+ (i_bytes + 8 > i_remaining) ||
+ memcmp("cdat", &p_block->p_buffer[4], 4) ||
+ !(p_newblock = block_Alloc( i_remaining * 3 - 8 )) )
+ {
+ p_block->i_buffer = 0;
+ return p_block;
+ }
+
+ uint8_t *p_write = p_newblock->p_buffer;
+ uint8_t *p_read = &p_block->p_buffer[8];
+ i_bytes -= 8;
+ i_remaining -= 8;
+
+ do
+ {
+ p_write[i_copied++] = 0; /* cc1 == field 0 */
+ p_write[i_copied++] = p_read[0];
+ p_write[i_copied++] = p_read[1];
+ p_read += 2;
+ i_bytes -= 2;
+ i_remaining -= 2;
+ } while( i_bytes >= 2 );
+
+ if ( i_remaining >= 10 &&
+ (i_bytes = GetDWBE(p_read)) &&
+ (i_bytes + 8 <= i_remaining) &&
+ !memcmp("cdt2", &p_read[4], 4) )
+ {
+ p_read += 8;
+ i_bytes -= 8;
+ i_remaining -= 8;
+ do
+ {
+ p_write[i_copied++] = 0; /* cc1 == field 0 */
+ p_write[i_copied++] = p_read[0];
+ p_write[i_copied++] = p_read[1];
+ p_read += 2;
+ i_bytes -= 2;
+ } while( i_bytes >= 2 );
+ }
+
+ block_Release( p_block );
+ p_newblock->i_buffer = i_copied;
+ return p_newblock;
+}
+
static block_t * MP4_Block_Read( demux_t *p_demux, const mp4_track_t *p_track, int i_size )
{
block_t *p_block = stream_Block( p_demux->s, i_size );
@@ -407,7 +463,9 @@ static block_t * MP4_Block_Read( demux_t *p_demux, const mp4_track_t *p_track, i
case VLC_CODEC_SPU:
/* accept as-is */
break;
-
+ case VLC_CODEC_EIA608_1:
+ p_block = MP4_EIA608_Convert( p_block );
+ break;
default:
p_block->i_buffer = 0;
break;
@@ -2438,7 +2496,6 @@ static int TrackCreateES( demux_t *p_demux, mp4_track_t *p_track,
break;
}
-
/* It's a little ugly but .. there are special cases */
switch( p_sample->i_type )
{
@@ -2516,6 +2573,12 @@ static int TrackCreateES( demux_t *p_demux, mp4_track_t *p_track,
p_track->fmt.i_codec = VLC_CODEC_H263;
break;
+ case( ATOM_c608 ): /* EIA608 closed captions */
+ //case( ATOM_c708 ): /* EIA708 closed captions */
+ p_track->fmt.i_codec = VLC_CODEC_EIA608_1;
+ p_track->fmt.i_cat = SPU_ES;
+ break;
+
case( VLC_FOURCC( 't', 'e', 'x', 't' ) ):
case( VLC_FOURCC( 't', 'x', '3', 'g' ) ):
{
@@ -3219,6 +3282,11 @@ static void MP4_TrackCreate( demux_t *p_demux, mp4_track_t *p_track,
p_track->fmt.i_cat = SPU_ES;
break;
+ /* closed captions */
+ case( ATOM_clcp ):
+ p_track->fmt.i_cat = SPU_ES;
+ break;
+
default:
return;
}
--
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