Added CD+G file support:

 - as a standalone file
 - as a kind of subtitle (even if it is a video track).
CD-G disk are not supported.

Please, report any file incorrectly decoded. (I have 0 sample with
circular scrolling)

In subtitle_Detect, do not add as a subtitle the file for which we
are doing the detection.
 (subtitle_Detect("file.sub") returned "file.sub")

modules/codec/cdg.c

+/*****************************************************************************
+ * cdg.c: CDG decoder module
+ *****************************************************************************
+ * Copyright (C) 2007 Laurent Aimar
+ * $Id: $
+ *
+ * Authors: Laurent Aimar <fenrir # via.ecp.fr>
+ *
+ * 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
+ *****************************************************************************/
+#include <vlc/vlc.h>
+#include <vlc_codec.h>
+#include <vlc_vout.h>
+
+/*****************************************************************************
+ * decoder_sys_t : decoder descriptor
+ *****************************************************************************/
+
+/* The screen size */
+#define CDG_SCREEN_WIDTH (300)
+#define CDG_SCREEN_HEIGHT (216)
+
+/* The border of the screen size */
+#define CDG_SCREEN_BORDER_WIDTH (6)
+#define CDG_SCREEN_BORDER_HEIGHT (12)
+
+/* The display part */
+#define CDG_DISPLAY_WIDTH  (CDG_SCREEN_WIDTH-2*CDG_SCREEN_BORDER_WIDTH)
+#define CDG_DISPLAY_HEIGHT (CDG_SCREEN_HEIGHT-2*CDG_SCREEN_BORDER_HEIGHT)
+
+#define CDG_SCREEN_PITCH (CDG_SCREEN_WIDTH)
+
+struct decoder_sys_t
+{
+    uint8_t color[16][3];
+    int     i_offseth;
+    int     i_offsetv;
+    uint8_t screen[CDG_SCREEN_PITCH*CDG_SCREEN_HEIGHT];
+    uint8_t *p_screen;
+};
+
+#define CDG_PACKET_SIZE (24)
+
+#define CDG_COLOR_R_SHIFT ( 0)
+#define CDG_COLOR_G_SHIFT ( 8)
+#define CDG_COLOR_B_SHIFT (16)
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int  Open ( vlc_object_t * );
+static void Close( vlc_object_t * );
+
+static picture_t *Decode( decoder_t *, block_t ** );
+
+static int DecodePacket( decoder_sys_t *p_cdg, uint8_t *p_buffer, int i_buffer );
+static int Render( decoder_sys_t *p_cdg, picture_t *p_picture );
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+vlc_module_begin();
+    set_category( CAT_INPUT );
+    set_subcategory( SUBCAT_INPUT_VCODEC );
+    set_description( _("CDG video decoder") );
+    set_capability( "decoder", 1000 );
+    set_callbacks( Open, Close );
+    add_shortcut( "cdg" );
+vlc_module_end();
+
+/*****************************************************************************
+ * Open: probe the decoder and return score
+ *****************************************************************************/
+static int Open( vlc_object_t *p_this )
+{
+    decoder_t *p_dec = (decoder_t*)p_this;
+    decoder_sys_t *p_sys;
+
+    if( p_dec->fmt_in.i_codec != VLC_FOURCC('C','D','G',' ') )
+        return VLC_EGENERIC;
+
+    /* Allocate the memory needed to store the decoder's structure */
+    p_dec->p_sys = p_sys = malloc(sizeof(decoder_sys_t));
+    if( !p_sys )
+    {
+        msg_Err( p_dec, "out of memory" );
+        return VLC_EGENERIC;
+    }
+
+    /* Init */
+    memset( p_sys, 0, sizeof(*p_sys) );
+    p_sys->i_offseth = 0;
+    p_sys->i_offsetv = 0;
+    p_sys->p_screen = p_sys->screen;
+
+    /* Set output properties
+     * TODO maybe it would be better to use RV16 or RV24 ? */
+    p_dec->fmt_out.i_cat = VIDEO_ES;
+    p_dec->fmt_out.i_codec = VLC_FOURCC('R','V','3','2');
+    p_dec->fmt_out.video.i_width = CDG_DISPLAY_WIDTH;
+    p_dec->fmt_out.video.i_height = CDG_DISPLAY_HEIGHT;
+    p_dec->fmt_out.video.i_aspect =
+        VOUT_ASPECT_FACTOR * p_dec->fmt_out.video.i_width / p_dec->fmt_out.video.i_height;
+    p_dec->fmt_out.video.i_rmask = 0xff << CDG_COLOR_R_SHIFT;
+    p_dec->fmt_out.video.i_gmask = 0xff << CDG_COLOR_G_SHIFT;
+    p_dec->fmt_out.video.i_bmask = 0xff << CDG_COLOR_B_SHIFT;
+
+    /* Set callbacks */
+    p_dec->pf_decode_video = Decode;
+
+    return VLC_SUCCESS;
+}
+
+/****************************************************************************
+ * Decode: the whole thing
+ ****************************************************************************
+ * This function must be fed with a complete compressed frame.
+ ****************************************************************************/
+static picture_t *Decode( decoder_t *p_dec, block_t **pp_block )
+{
+    decoder_sys_t *p_sys = p_dec->p_sys;
+    block_t *p_block;
+    picture_t *p_pic = NULL;
+
+    if( !pp_block || !*pp_block )
+        return NULL;
+    p_block = *pp_block;
+
+    /* Decode packet */
+    while( p_block->i_buffer >= CDG_PACKET_SIZE )
+    {
+        DecodePacket( p_sys, p_block->p_buffer, CDG_PACKET_SIZE );
+        p_block->i_buffer -= CDG_PACKET_SIZE;
+        p_block->p_buffer += CDG_PACKET_SIZE;
+    }
+
+    /* Get a new picture */
+    p_pic = p_dec->pf_vout_buffer_new( p_dec );
+    if( !p_pic )
+        goto error;
+
+    Render( p_sys, p_pic );
+    p_pic->date = p_block->i_pts > 0 ? p_block->i_pts : p_block->i_dts;
+
+    block_Release( p_block ); *pp_block = NULL;
+    return p_pic;
+
+error:
+    block_Release( p_block ); *pp_block = NULL;
+    return NULL;
+}
+
+/*****************************************************************************
+ * Close: decoder destruction
+ *****************************************************************************/
+static void Close( vlc_object_t *p_this )
+{
+    decoder_t *p_dec = (decoder_t *)p_this;
+    decoder_sys_t *p_sys = p_dec->p_sys;
+
+    free( p_sys );
+}
+
+/*****************************************************************************
+ * Decoder
+ *****************************************************************************/
+static void ScreenFill( decoder_sys_t *p_cdg, int sx, int sy, int dx, int dy, int c )
+{
+    int x, y;
+    for( y = sy; y < sy+dy; y++ )
+        for( x = sx; x < sx+dx; x++ )
+            p_cdg->p_screen[y*CDG_SCREEN_PITCH+x] = c;
+}
+static int DecodeMemoryPreset( decoder_sys_t *p_cdg, const uint8_t *p_data )
+{
+    const int i_color = p_data[0]&0x0f;
+    const int i_repeat= p_data[1]&0x0f;
+
+    /* if i_repeat > 0 we could ignore it if we have a reliable stream */
+    ScreenFill( p_cdg, 0, 0, CDG_SCREEN_WIDTH, CDG_SCREEN_HEIGHT, i_color );
+    return 0;
+}
+static int DecodeBorderPreset( decoder_sys_t *p_cdg, const uint8_t *p_data )
+{
+    const int i_color = p_data[0]&0x0f;
+
+    /* */
+    ScreenFill( p_cdg,   0,   0,
+                CDG_SCREEN_WIDTH, CDG_SCREEN_BORDER_HEIGHT, i_color );
+    ScreenFill( p_cdg,   0, CDG_SCREEN_HEIGHT-CDG_SCREEN_BORDER_HEIGHT,
+                CDG_SCREEN_WIDTH, CDG_SCREEN_BORDER_HEIGHT, i_color );
+    ScreenFill( p_cdg,   0, CDG_SCREEN_BORDER_HEIGHT,
+                CDG_SCREEN_BORDER_WIDTH, CDG_SCREEN_HEIGHT-CDG_SCREEN_BORDER_HEIGHT, i_color );
+    ScreenFill( p_cdg,   CDG_SCREEN_WIDTH-CDG_SCREEN_BORDER_WIDTH, CDG_SCREEN_BORDER_HEIGHT,
+                CDG_SCREEN_BORDER_WIDTH, CDG_SCREEN_HEIGHT-CDG_SCREEN_BORDER_HEIGHT, i_color );
+    return 0;
+}
+
+static int DecodeLoadColorTable( decoder_sys_t *p_cdg, const uint8_t *p_data, int i_base )
+{
+    int n;
+    for( n = 0; n < 8; n++ )
+    {
+        const int c = ((p_data[2*n+0] << 8) | p_data[2*n+1]);
+        const int r = (c >> 10)&0x0f;
+        const int g = ((c >> 6)&0x0c) | ((c >> 4)&0x03);
+        const int b = c &0x0f;
+
+        p_cdg->color[i_base+n][0] = r << 4;
+        p_cdg->color[i_base+n][1] = g << 4;
+        p_cdg->color[i_base+n][2] = b << 4;
+    }
+    return 0;
+}
+static int DecodeTileBlock( decoder_sys_t *p_cdg, const uint8_t *p_data, int doXor )
+{
+    int p_color[2];
+    int sx, sy;
+    int x, y;
+
+    p_color[0] = p_data[0] & 0x0f;
+    p_color[1] = p_data[1] & 0x0f;
+
+    sy = (p_data[2] & 0x1f)*12;
+    sx = (p_data[3] & 0x3f)*6;
+
+    for( y = 0; y < 12; y++ )
+    {
+        for( x = 0; x < 6; x++ )
+        {
+            const int idx = ( p_data[4+y] >> (5-x) ) & 0x01;
+            uint8_t *p = &p_cdg->p_screen[(sy+y)*CDG_SCREEN_PITCH+(sx+x)];
+            if( doXor )
+                *p ^= p_color[idx];
+            else
+                *p = p_color[idx];
+        }
+    }
+    return 0;
+}
+
+static int DecodeScroll( decoder_sys_t *p_cdg, const uint8_t *p_data, int b_copy )
+{
+    uint8_t copy[CDG_SCREEN_PITCH*CDG_SCREEN_HEIGHT];
+
+    uint8_t color = p_data[0]&0x0f;
+    int i_shifth;
+    int i_shiftv;
+    int x, y;
+
+    /* */
+    p_cdg->i_offseth = p_data[1]&0x7;
+    if( p_cdg->i_offseth >= CDG_SCREEN_BORDER_WIDTH )
+        p_cdg->i_offseth = CDG_SCREEN_BORDER_WIDTH-1;
+
+    p_cdg->i_offsetv = p_data[2]&0xf;
+    if( p_cdg->i_offsetv >= CDG_SCREEN_BORDER_HEIGHT )
+        p_cdg->i_offsetv = CDG_SCREEN_BORDER_HEIGHT-1;
+
+    /* */
+    switch( (p_data[1] >> 4)&0x3 )
+    {
+    case 0x01: i_shifth =  6; break;
+    case 0x02: i_shifth = -6; break;
+    default:
+        i_shifth = 0;
+        break;
+    }
+    switch( (p_data[2] >> 4)&0x3 )
+    {
+    case 0x01: i_shiftv = 12; break;
+    case 0x02: i_shiftv =-12; break;
+    default:
+        i_shiftv = 0;
+        break;
+    }
+
+    if( i_shifth == 0 && i_shiftv == 0 )
+        return 0;
+
+    /* Make a copy of the screen */
+    memcpy( copy, p_cdg->screen, sizeof(p_cdg->screen) );
+
+    /* Fill the uncovered part XXX way too much */
+    ScreenFill( p_cdg, 0, 0, CDG_SCREEN_WIDTH, CDG_SCREEN_HEIGHT, color );
+
+    /* Copy back */
+    for( y = 0; y < CDG_SCREEN_HEIGHT; y++ )
+    {
+        int dy = i_shiftv + y;
+        for( x = 0; x < CDG_SCREEN_WIDTH; x++ )
+        {
+            int dx = i_shifth + x;
+
+            if( b_copy )
+            {
+                dy = ( dy + CDG_SCREEN_HEIGHT ) % CDG_SCREEN_HEIGHT;
+                dy = ( dy + CDG_SCREEN_WIDTH  ) % CDG_SCREEN_WIDTH;
+            }
+            else
+            {
+                if( dy < 0 || dy >= CDG_SCREEN_HEIGHT ||
+                    dx < 0 || dx >= CDG_SCREEN_WIDTH )
+                    continue;
+            }
+            p_cdg->screen[dy*CDG_SCREEN_PITCH+dx] = copy[y*CDG_SCREEN_PITCH+x];
+        }
+    }
+    /* */
+    //CdgDebug( CDG_LOG_WARNING, "DecodeScroll: color=%d ch=%d oh=%d cv=%d ov=%d\n copy=%d\n", color, i_shifth, p_cdg->i_offseth, i_shiftv, p_cdg->i_offsetv, b_copy );
+    return 0;
+}
+
+static int DecodePacket( decoder_sys_t *p_cdg, uint8_t *p_buffer, int i_buffer )
+{
+    const int i_cmd = p_buffer[0] & 0x3f;
+    const int i_instruction = p_buffer[1] & 0x3f;
+    const uint8_t *p_data = &p_buffer[4];
+
+    if( i_buffer != CDG_PACKET_SIZE )
+        return -1;
+
+    /* Handle CDG command only */
+    if( i_cmd != 0x09 )
+        return 0;
+
+    switch( i_instruction )
+    {
+        case 1:
+            DecodeMemoryPreset( p_cdg, p_data );
+            break;
+        case 2:
+            DecodeBorderPreset( p_cdg, p_data );
+            break;
+        case 6:
+            DecodeTileBlock( p_cdg, p_data, 0 );
+            break;
+        case 20:
+            DecodeScroll( p_cdg, p_data, 0 );
+            break;
+        case 24:
+            DecodeScroll( p_cdg, p_data, 1 );
+            break;
+        case 28:
+            /* FIXME what to do about that one ? */
+            //CdgDebug( CDG_LOG_WARNING, "DecodeDefineTransparentColor not implemented\n" );
+            //DecodeDefineTransparentColor( p_cdg, p_data );
+            break;
+        case 30:
+            DecodeLoadColorTable( p_cdg, p_data, 0 );
+            break;
+        case 31:
+            DecodeLoadColorTable( p_cdg, p_data, 8 );
+            break;
+        case 38:
+            DecodeTileBlock( p_cdg, p_data, 1 );
+            break;
+        default:
+            break;
+    }
+    return 0;
+}
+
+static void RenderPixel( picture_t *p_picture, int x, int y, uint32_t c )
+{
+    const int i_plane = 0;
+    const int i_pitch = p_picture->p[i_plane].i_pitch;
+    uint32_t *s = (uint32_t*)&p_picture->p[i_plane].p_pixels[y*i_pitch + x*sizeof(uint32_t)];
+    *s = c;
+}
+static uint32_t RenderRGB( int r, int g, int b )
+{
+    return ( r << CDG_COLOR_R_SHIFT ) | ( g << CDG_COLOR_G_SHIFT ) | ( b << CDG_COLOR_B_SHIFT );
+}
+
+static int Render( decoder_sys_t *p_cdg, picture_t *p_picture )
+{
+    int x, y;
+
+    for( y = 0; y < CDG_DISPLAY_HEIGHT; y++ )
+    {
+        for( x = 0; x < CDG_DISPLAY_WIDTH; x++ )
+        {
+            const int sx = x + p_cdg->i_offseth + CDG_SCREEN_BORDER_WIDTH;
+            const int sy = y + p_cdg->i_offsetv + CDG_SCREEN_BORDER_HEIGHT;
+            uint8_t cidx = p_cdg->p_screen[sy*CDG_SCREEN_PITCH +sx];
+            uint8_t r = p_cdg->color[cidx][0];
+            uint8_t g = p_cdg->color[cidx][1];
+            uint8_t b = p_cdg->color[cidx][2];
+
+            RenderPixel( p_picture, x, y, RenderRGB( r, g, b ) );
+        }
+    }
+    return 0;
+}
+

modules/demux/cdg.c

+/*****************************************************************************
+ * cdg.c : cdg file demux module for vlc
+ *****************************************************************************
+ * Copyright (C) 2007 Laurent Aimar
+ * $Id: $
+ *
+ * Authors: Laurent Aimar <fenrir # via.ecp.fr>
+ *
+ * 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
+ *****************************************************************************/
+
+#include <vlc/vlc.h>
+#include <vlc_demux.h>
+
+#include <vlc_codecs.h>
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+static int  Open ( vlc_object_t * );
+static void Close( vlc_object_t * );
+
+vlc_module_begin();
+    set_description( _("CDG demuxer") );
+    set_category( CAT_INPUT );
+    set_subcategory( SUBCAT_INPUT_DEMUX );
+    set_capability( "demux2", 2 );
+    set_callbacks( Open, Close );
+    add_shortcut( "cdg" );
+    add_shortcut( "subtitle" );
+vlc_module_end();
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int Demux  ( demux_t * );
+static int Control( demux_t *, int i_query, va_list args );
+
+struct demux_sys_t
+{
+    es_format_t     fmt;
+    es_out_id_t     *p_es;
+
+    date_t          pts;
+};
+
+#define CDG_FRAME_SIZE (96)
+#define CDG_FRAME_RATE (75)
+
+/*****************************************************************************
+ * Open: check file and initializes structures
+ *****************************************************************************/
+static int Open( vlc_object_t * p_this )
+{
+    demux_t     *p_demux = (demux_t*)p_this;
+    demux_sys_t *p_sys;
+
+    /* Identify cdg file by extension, as there is no simple way to
+     * detect it */
+    if( !demux2_IsPathExtension( p_demux, ".cdg" ) &&
+        !demux2_IsPathExtension( p_demux, ".CDG" ) &&
+        !demux2_IsForced( p_demux, "cdg" ) )
+        return VLC_EGENERIC;
+
+    /* CDG file size has to be multiple of CDG_FRAME_SIZE (it works even
+     * if size is unknown ie 0) */
+//    if( (stream_Size( p_demux->s ) % CDG_FRAME_SIZE) != 0 )
+//    {
+//        msg_Err( p_demux, "Reject CDG file based on its size" );
+//        return VLC_EGENERIC;
+//    }
+
+    p_demux->pf_demux   = Demux;
+    p_demux->pf_control = Control;
+    p_demux->p_sys      = p_sys = malloc( sizeof( demux_sys_t ) );
+
+    /* */
+    es_format_Init( &p_sys->fmt, VIDEO_ES, VLC_FOURCC('C','D','G', ' ' ) );
+    p_sys->fmt.video.i_width  = 300-2*6;
+    p_sys->fmt.video.i_height = 216-2*12 ;
+
+    p_sys->p_es = es_out_Add( p_demux->out, &p_sys->fmt );
+
+    /* There is CDG_FRAME_RATE frames per second */
+    date_Init( &p_sys->pts, CDG_FRAME_RATE, 1 );
+    date_Set( &p_sys->pts, 1 );
+
+    return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * Demux: read packet and send them to decoders
+ *****************************************************************************
+ * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
+ *****************************************************************************/
+static int Demux( demux_t *p_demux )
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+    block_t     *p_block;
+
+    p_block = stream_Block( p_demux->s, CDG_FRAME_SIZE );
+    if( p_block == NULL )
+    {
+        msg_Dbg( p_demux, "cannot read data, eof" );
+        return 0;
+    }
+
+    p_block->i_dts =
+    p_block->i_pts = date_Increment( &p_sys->pts, 1 );
+
+    es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block->i_pts );
+
+    es_out_Send( p_demux->out, p_sys->p_es, p_block );
+    return 1;
+}
+
+/*****************************************************************************
+ * Close: frees unused data
+ *****************************************************************************/
+static void Close ( vlc_object_t * p_this )
+{
+    demux_t *p_demux = (demux_t *)p_this;
+    demux_sys_t *p_sys = p_demux->p_sys;
+
+    free( p_sys );
+}
+
+/*****************************************************************************
+ * Control:
+ *****************************************************************************/
+static int Control( demux_t *p_demux, int i_query, va_list args )
+{
+    demux_sys_t *p_sys  = p_demux->p_sys;
+    int64_t *pi64;
+
+    switch( i_query )
+    {
+#if 0
+    case DEMUX_GET_TIME:
+        pi64 = (int64_t*)va_arg( args, int64_t * );
+        *pi64 = date_Get( &p_sys->pts );
+        return VLC_SUCCESS;
+#endif
+    default:
+        return demux2_vaControlHelper( p_demux->s, 0, -1,
+                                       8*CDG_FRAME_SIZE*CDG_FRAME_RATE, CDG_FRAME_SIZE, i_query, args );
+    }
+}
+

src/input/subtitles.c

@@ -59,7 +59,11 @@
 static const char const sub_exts[][6] = {
     "utf", "utf8", "utf-8",
     "sub", "srt", "smi",
-    "txt", "ssa", "idx", ""
+    "txt", "ssa", "idx",
+
+    "cdg",
+
+    ""
 };
 
 /* extensions from unsupported types */
@@ -400,6 +404,9 @@ char **subtitles_Detect( input_thread_t *p_this, char *psz_path,
                     struct stat st;
 
                     sprintf( psz_path, "%s%s", psz_dir, psz_name );
+                    if( !strcmp( psz_path, psz_fname ) )
+                        continue;
+
                     msg_Dbg( p_this,
                                 "autodetected subtitle: %s with priority %d",
                                 psz_path, i_prio );
@@ -460,6 +467,14 @@ char **subtitles_Detect( input_thread_t *p_this, char *psz_path,
                 i_result2++;
             }
         }
+        else if( result[j].psz_ext && !strcasecmp( result[j].psz_ext, "cdg" ) )
+        {
+            if( result[j].priority == 4 )
+            {
+                result2[i_result2] = result[j].psz_fname;
+                i_result2++;
+            }
+        }
         else
         {
             result2[i_result2] = result[j].psz_fname;