[MPlayer-dev-eng] [PATCH] Add DVB teletext support

Reimar Döffinger Reimar.Doeffinger at gmx.de
Sat Nov 7 13:50:15 CET 2009


On Sat, Nov 07, 2009 at 11:00:13AM +0100, Francesco Lavra wrote:
> Index: libmpdemux/demux_lavf.c
> ===================================================================
> --- libmpdemux/demux_lavf.c     (revision 29843)
> +++ libmpdemux/demux_lavf.c     (working copy)
> @@ -384,6 +384,8 @@
>                  type = 'a';
>              else if(codec->codec_id == CODEC_ID_DVD_SUBTITLE)
>                  type = 'v';
> +            else if(codec->codec_id == CODEC_ID_DVB_TELETEXT)
> +                type = 'd';
>              else
>                  break;
>              sh_sub = new_sh_sub_sid(demuxer, i, priv->sub_streams);

I'd say that can be applied.

> Index: libmpcodecs/dec_teletext.c
> ===================================================================
> --- libmpcodecs/dec_teletext.c	(revision 29843)
> +++ libmpcodecs/dec_teletext.c	(working copy)
> @@ -1454,6 +1454,45 @@
>  #endif
>  
>  /**
> + * \brief decodes one vbi line from one video frame
> + * \param priv private data structure
> + * \param data buffer with raw vbi data in it
> + */
> +static void vbi_decode_line(priv_vbi_t *priv, unsigned char *data) {
> +    int d0,d1;
> +    int magAddr;
> +    int pkt;
> +
> +    d0= corrHamm48[ data[0] ];
> +    d1= corrHamm48[ data[1] ];
> +
> +    if(d0&0x80 || d1&0x80){
> +        pll_add(priv,2,4);
> +        mp_msg(MSGT_TELETEXT,MSGL_V,"vbi_decode_line: HammErr\n");
> +
> +        return; //hamError
> +    }
> +    magAddr=d0 & 0x7;
> +    pkt=(d0>>3)|(d1<<1);
> +    mp_msg(MSGT_TELETEXT,MSGL_DBG3,"vbi_decode_line:%x %x (mag:%x, pkt:%d)\n",
> +            d0,d1,magAddr,pkt);
> +    if(!pkt){
> +        decode_pkt0(priv,data+2,magAddr); //skip MRGA
> +    }else if(pkt>0 && pkt<VBI_ROWS){
> +        if(!priv->mag[magAddr].pt) return;
> +        decode_pkt_page(priv,data+2,magAddr,pkt);//skip MRGA
> +    }else if(pkt==27) {
> +        decode_pkt27(priv,data+2,magAddr);
> +    }else if(pkt==28){
> +        decode_pkt28(priv,data+2);
> +    }else if(pkt==30){
> +        decode_pkt30(priv,data+2,magAddr);
> +    } else {
> +        mp_msg(MSGT_TELETEXT,MSGL_DBG3,"unsupported packet:%d\n",pkt);
> +    }
> +}
> +
> +/**
>   * \brief decodes all vbi lines from one video frame
>   * \param priv private data structure
>   * \param buf buffer with raw vbi data in it
> @@ -1461,11 +1500,8 @@
>   * \note buffer size have to be at least priv->ptsp->bufsize bytes
>   */
>  static void vbi_decode(priv_vbi_t* priv,unsigned char*buf){
> -    int magAddr;
> -    int pkt;
>      unsigned char data[64];
>      unsigned char* linep;
> -    int d0,d1;
>      int i=0;
>      mp_msg(MSGT_TELETEXT,MSGL_DBG3,"vbi: vbi_decode\n");
>      for(linep=buf; !priv->cache_reset && linep<buf+priv->ptsp->bufsize; linep+=priv->ptsp->samples_per_line,i++){
> @@ -1480,33 +1516,7 @@
>          if(decode_raw_line_runin(priv,linep,data)<=0){
>               continue; //this is not valid teletext line
>          }
> -        d0= corrHamm48[ data[0] ];
> -        d1= corrHamm48[ data[1] ];
> -
> -        if(d0&0x80 || d1&0x80){
> -           pll_add(priv,2,4);
> -           mp_msg(MSGT_TELETEXT,MSGL_V,"vbi_decode(%d):HammErr after decode_raw_line\n",i);
> -
> -           continue; //hamError
> -        }
> -        magAddr=d0 & 0x7;
> -        pkt=(d0>>3)|(d1<<1);
> -        mp_msg(MSGT_TELETEXT,MSGL_DBG3,"vbi_decode(%d):%x %x (mag:%x, pkt:%d)\n",
> -            i,d0,d1,magAddr,pkt);
> -        if(!pkt){
> -            decode_pkt0(priv,data+2,magAddr); //skip MRGA
> -        }else if(pkt>0 && pkt<VBI_ROWS){
> -            if(!priv->mag[magAddr].pt) continue;
> -            decode_pkt_page(priv,data+2,magAddr,pkt);//skip MRGA
> -        }else if(pkt==27) {
> -            decode_pkt27(priv,data+2,magAddr);
> -        }else if(pkt==28){
> -            decode_pkt28(priv,data+2);
> -        }else if(pkt==30){
> -            decode_pkt30(priv,data+2,magAddr);
> -        } else {
> -            mp_msg(MSGT_TELETEXT,MSGL_DBG3,"unsupported packet:%d\n",pkt);
> -        }
> +        vbi_decode_line(priv, data);
>      }
>      if (priv->cache_reset){
>          pthread_mutex_lock(&(priv->buffer_mutex));

That should be easy to test/verify separately and also reduces the size
of this huge function, so I'd suggest applying this first.

> @@ -1516,6 +1526,64 @@
>  
>  }
>  
> +/**
> + * \brief decodes a vbi line from a DVB teletext stream
> + * \param priv private data structure
> + * \param buf buffer with DVB teletext data
> + */
> +static void vbi_decode_dvb(priv_vbi_t *priv,unsigned char *buf){
> +    static const u_int8_t byterev8[256] = {
> +        0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 
> +        0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, 
> +        0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, 
> +        0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, 
> +        0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 
> +        0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, 
> +        0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 
> +        0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, 
> +        0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 
> +        0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, 
> +        0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, 
> +        0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, 
> +        0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 
> +        0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, 
> +        0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 
> +        0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, 
> +        0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, 
> +        0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, 
> +        0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 
> +        0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, 
> +        0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, 
> +        0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, 
> +        0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 
> +        0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, 
> +        0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 
> +        0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, 
> +        0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 
> +        0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, 
> +        0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, 
> +        0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, 
> +        0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 
> +        0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
> +    };
> +    int i;
> +    unsigned char data[42];
> +
> +    mp_msg(MSGT_TELETEXT,MSGL_DBG3, "vbi: vbi_decode_dvb\n");
> +
> +    /* Reverse bit order, skipping the first two bytes (field parity, line
> +       offset and framing code). */
> +    for (i = 0; i < sizeof(data); i++)
> +        data[i] = byterev8[buf[2 + i]];
> +
> +    vbi_decode_line(priv, data);

Can't this be done in-place, i.e.

for (i = 2; i < 44; i++)
    buf[i] = byterev8[buf[i]];
vbi_decode_line(priv, buf + 2);

Maybe it is better not to, but then buf should be declared const.

> +    if (priv->cache_reset){
> +        pthread_mutex_lock(&(priv->buffer_mutex));
> +        priv->cache_reset--;
> +        pthread_mutex_unlock(&(priv->buffer_mutex));

useless ()

> Index: mpcommon.c
> ===================================================================
> --- mpcommon.c	(revision 29843)
> +++ mpcommon.c	(working copy)
> @@ -141,9 +141,17 @@
>  
>          if (spudec_changed(vo_spudec))
>              vo_osd_changed(OSDTYPE_SPU);
> -    } else if (dvdsub_id >= 0 && (type == 't' || type == 'm' || type == 'a')) {
> +    } else if (dvdsub_id >= 0 && (type == 't' || type == 'm' || type == 'a' || type == 'd')) {
>          double curpts = refpts + sub_delay;
>          double endpts;
> +        if (type == 'd' && !d_dvdsub->demuxer->teletext) {
> +            tt_stream_props tsp;
> +            memset(&tsp, 0, sizeof(tsp));
> +            d_dvdsub->demuxer->teletext = &tsp;

WTF? You can't assign the address of a stack variable to a globally
available pointer.



More information about the MPlayer-dev-eng mailing list