[vlc-devel] [PATCH] cdg: fix seek

[Jean-Baptiste Kempf]

Thanks, applied.

On 17 Nov, Zhao Zhili wrote :
> The video output is messed up if we only do a stream_Seek(). If we want
> to seeking forward, we should decode and discard pictures to keep the
> decoder at the right state. For seeking backward, seeking to the
> beginning and decode from there. Since the bitrate is very low and the
> decodeing process is really simple, there is no obvious delay. I have
> tested this strategy on a dual core ARM board.
> ---
>  modules/codec/cdg.c |  2 +-
>  modules/demux/cdg.c | 26 ++++++++++++++++++++++----
>  2 files changed, 23 insertions(+), 5 deletions(-)
> 
> diff --git a/modules/codec/cdg.c b/modules/codec/cdg.c
> index 98c07c8..763ba1a 100644
> --- a/modules/codec/cdg.c
> +++ b/modules/codec/cdg.c
> @@ -158,7 +158,7 @@ static picture_t *Decode( decoder_t *p_dec, block_t
> **pp_block )
>      }
> 
>      /* Only display 25 frame per second (there is 75 packets per second) */
> -    if( (p_sys->i_packet%3) == 1 )
> +    if( (p_sys->i_packet%3) == 1 && p_block->i_pts == p_block->i_dts )
>      {
>          /* Get a new picture */
>          p_pic = decoder_NewPicture( p_dec );
> diff --git a/modules/demux/cdg.c b/modules/demux/cdg.c
> index 212a4f3..14df882 100644
> --- a/modules/demux/cdg.c
> +++ b/modules/demux/cdg.c
> @@ -119,6 +119,10 @@ static int Demux( demux_t *p_demux )
>  {
>      demux_sys_t *p_sys = p_demux->p_sys;
>      block_t     *p_block;
> +    mtime_t     i_date;
> +    mtime_t     i_delta;
> +
> +    i_delta = INT64_C(1000000) / CDG_FRAME_RATE;
> 
>      p_block = stream_Block( p_demux->s, CDG_FRAME_SIZE );
>      if( p_block == NULL )
> @@ -127,15 +131,22 @@ static int Demux( demux_t *p_demux )
>          return 0;
>      }
> 
> -    p_block->i_dts =
> -    p_block->i_pts = VLC_TS_0 + date_Get( &p_sys->pts );
> +    i_date = stream_Tell( p_demux->s ) / CDG_FRAME_SIZE * i_delta;
> +    if( i_date >= date_Get( &p_sys->pts ) + i_delta )
> +    {
> +        p_block->i_dts = p_block->i_pts = i_date;
> +        date_Set( &p_sys->pts, i_date );
> +    }
> +    else
> +    {
> +        p_block->i_dts = i_date;
> +        p_block->i_pts = date_Get( &p_sys->pts );
> +    }
> 
>      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 );
> 
> -    date_Increment( &p_sys->pts, 1 );
> -
>      return 1;
>  }
> 
> @@ -155,13 +166,20 @@ static void Close ( vlc_object_t * p_this )
> 
> *****************************************************************************/
>  static int Control( demux_t *p_demux, int i_query, va_list args )
>  {
> +    uint64_t i_old_offset = stream_Tell( p_demux->s );
>      int i_ret = demux_vaControlHelper( p_demux->s, 0, -1,
>                                         8*CDG_FRAME_SIZE*CDG_FRAME_RATE,
> CDG_FRAME_SIZE,
>                                         i_query, args );
>      if( !i_ret && ( i_query == DEMUX_SET_POSITION || i_query ==
> DEMUX_SET_TIME ) )
> +    {
>          date_Set( &p_demux->p_sys->pts,
>                    stream_Tell( p_demux->s ) / CDG_FRAME_SIZE *
>                      INT64_C(1000000) / CDG_FRAME_RATE );
> +        if ( i_old_offset > stream_Tell( p_demux->s ) )
> +            i_ret = stream_Seek( p_demux->s, 0 );
> +        else
> +            i_ret = stream_Seek( p_demux->s, i_old_offset );
> +    }
> 
>      return i_ret;
>  }
> -- 
> 1.9.1

> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel


-- 
With my kindest regards,

-- 
Jean-Baptiste Kempf
http://www.jbkempf.com/ - +33 672 704 734
Sent from my Electronic Device