libmpeg2.c

video linux conference

                {
                    /* Invalid aspect, assume 4:3.
                     * This shouldn't happen and if it does it is a bug
                     * in libmpeg2 (likely triggered by an invalid stream) */
                    p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
                }
            }

            msg_Dbg( p_dec, "%dx%d, aspect %d, %u.%03u fps",
                     p_sys->p_info->sequence->width,
                     p_sys->p_info->sequence->height, p_sys->i_aspect,
                     (uint32_t)((uint64_t)1001000000 * 27 /
                         p_sys->p_info->sequence->frame_period / 1001),
                     (uint32_t)((uint64_t)1001000000 * 27 /
                         p_sys->p_info->sequence->frame_period % 1001) );

            mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );

            /* Set the first 2 reference frames */
            mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );

            if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
            {
                block_Release( p_block );
                return NULL;
            }

            mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );

            /* This picture will never go through display_picture. */
            p_pic->date = 0;

            /* For some reason, libmpeg2 will put this pic twice in
             * discard_picture. This can be considered a bug in libmpeg2. */
            p_dec->pf_picture_link( p_dec, p_pic );

            if( p_sys->p_synchro )
            {
                vout_SynchroRelease( p_sys->p_synchro );
            }
            p_sys->p_synchro = vout_SynchroInit( p_dec,
                (uint32_t)((uint64_t)1001000000 * 27 /
                p_sys->p_info->sequence->frame_period) );
            p_sys->b_after_sequence_header = 1;
        }
        break;

        case STATE_PICTURE_2ND:
            vout_SynchroNewPicture( p_sys->p_synchro,
                p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
                p_sys->p_info->current_picture->nb_fields,
                0, 0, p_sys->i_current_rate,
                p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );

            if( p_sys->b_skip )
            {
                vout_SynchroTrash( p_sys->p_synchro );
            }
            else
            {
                vout_SynchroDecode( p_sys->p_synchro );
            }
            break;

        case STATE_PICTURE:
        {
            uint8_t *buf[3];
            mtime_t i_pts, i_dts;
            buf[0] = buf[1] = buf[2] = NULL;

            if ( p_sys->b_after_sequence_header &&
                 ((p_sys->p_info->current_picture->flags &
                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
            {
                /* Intra-slice refresh. Simulate a blank I picture. */
                msg_Dbg( p_dec, "intra-slice refresh stream" );
                vout_SynchroNewPicture( p_sys->p_synchro,
                    I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
                    p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
                vout_SynchroDecode( p_sys->p_synchro );
                vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
                p_sys->b_slice_i = 1;
            }
            p_sys->b_after_sequence_header = 0;

#ifdef PIC_FLAG_PTS
            i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
                ( ( p_sys->p_info->current_picture->pts ==
                    (uint32_t)p_sys->i_current_pts ) ?
                  p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
            i_dts = 0;

            /* Hack to handle demuxers which only have DTS timestamps */
            if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
            {
                if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
                    (p_sys->p_info->current_picture->flags &
                      PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
                {
                    i_pts = p_block->i_dts;
                }
            }
            p_block->i_pts = p_block->i_dts = 0;
            /* End hack */

#else /* New interface */

            i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
                ( ( p_sys->p_info->current_picture->tag ==
                    (uint32_t)p_sys->i_current_pts ) ?
                  p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
            i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
                ( ( p_sys->p_info->current_picture->tag2 ==
                    (uint32_t)p_sys->i_current_dts ) ?
                  p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
#endif

            vout_SynchroNewPicture( p_sys->p_synchro,
                p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
                p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
                p_sys->i_current_rate,
                p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );

            if( !p_dec->b_pace_control && !p_sys->b_preroll &&
                !(p_sys->b_slice_i
                   && ((p_sys->p_info->current_picture->flags
                         & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
                   && !vout_SynchroChoose( p_sys->p_synchro,
                              p_sys->p_info->current_picture->flags
                                & PIC_MASK_CODING_TYPE,
                              /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
                              p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
            {
                mpeg2_skip( p_sys->p_mpeg2dec, 1 );
                p_sys->b_skip = 1;
                vout_SynchroTrash( p_sys->p_synchro );
                mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
            }
            else
            {
                mpeg2_skip( p_sys->p_mpeg2dec, 0 );
                p_sys->b_skip = 0;
                vout_SynchroDecode( p_sys->p_synchro );

                if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
                {
                    block_Release( p_block );
                    return NULL;
                }

                mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
            }
        }
        break;

        case STATE_END:
        case STATE_SLICE:
            p_pic = NULL;
            if( p_sys->p_info->display_fbuf
                && p_sys->p_info->display_fbuf->id )
            {
                p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;

                vout_SynchroEnd( p_sys->p_synchro,
                            p_sys->p_info->display_picture->flags
                             & PIC_MASK_CODING_TYPE,
                            p_sys->b_garbage_pic );
                p_sys->b_garbage_pic = 0;

                if ( p_sys->p_picture_to_destroy != p_pic )
                {
                    p_pic->date = vout_SynchroDate( p_sys->p_synchro );
                }
                else
                {
                    p_sys->p_picture_to_destroy = NULL;
                    p_pic->date = 0;
                }
            }

            if( p_sys->p_info->discard_fbuf &&
                p_sys->p_info->discard_fbuf->id )
            {
                p_dec->pf_picture_unlink( p_dec,
                                          p_sys->p_info->discard_fbuf->id );
            }

            /* For still frames */
            if( state == STATE_END && p_pic ) p_pic->b_force = VLC_TRUE;

            if( p_pic )
            {
                /* Avoid frames with identical timestamps.
                 * Especially needed for still frames in DVD menus. */
                if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
                p_sys->i_last_frame_pts = p_pic->date;

                return p_pic;
            }

            break;

        case STATE_INVALID:
        {
            uint8_t *buf[3];
            buf[0] = buf[1] = buf[2] = NULL;

            msg_Warn( p_dec, "invalid picture encountered" );
            if ( ( p_sys->p_info->current_picture == NULL ) ||
               ( ( p_sys->p_info->current_picture->flags &
                   PIC_MASK_CODING_TYPE) != B_CODING_TYPE ) )
            {
                if( p_sys->p_synchro ) vout_SynchroReset( p_sys->p_synchro );
            }
            mpeg2_skip( p_sys->p_mpeg2dec, 1 );
            p_sys->b_skip = 1;

            if( p_sys->p_info->current_fbuf &&
                p_sys->p_info->current_fbuf->id )
            {
                p_sys->b_garbage_pic = 1;
                p_pic = p_sys->p_info->current_fbuf->id;
            }
            else if( !p_sys->p_info->sequence )
            {
                break;
            }
            else
            {
                if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
                    break;
                mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
            }
            p_sys->p_picture_to_destroy = p_pic;

            memset( p_pic->p[0].p_pixels, 0,
                    p_sys->p_info->sequence->width
                     * p_sys->p_info->sequence->height );
            memset( p_pic->p[1].p_pixels, 0x80,
                    p_sys->p_info->sequence->width
                     * p_sys->p_info->sequence->height / 4 );
            memset( p_pic->p[2].p_pixels, 0x80,
                    p_sys->p_info->sequence->width
                     * p_sys->p_info->sequence->height / 4 );

            if( p_sys->b_slice_i )
            {
                vout_SynchroNewPicture( p_sys->p_synchro,
                        I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
                        p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
                vout_SynchroDecode( p_sys->p_synchro );
                vout_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
            }
            break;
        }

        default:
            break;
        }
    }

    /* Never reached */
    return NULL;
}

/*****************************************************************************
 * CloseDecoder: libmpeg2 decoder destruction
 *****************************************************************************/
static void CloseDecoder( vlc_object_t *p_this )
{
    decoder_t *p_dec = (decoder_t *)p_this;
    decoder_sys_t *p_sys = p_dec->p_sys;

    if( p_sys->p_synchro ) vout_SynchroRelease( p_sys->p_synchro );

    if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );

    free( p_sys );
}

/*****************************************************************************
 * GetNewPicture: Get a new picture from the vout and set the buf struct
 *****************************************************************************/
static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
{
    decoder_sys_t *p_sys = p_dec->p_sys;
    picture_t *p_pic;

    p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
    p_dec->fmt_out.video.i_visible_width =
        p_sys->p_info->sequence->picture_width;
    p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
    p_dec->fmt_out.video.i_visible_height =
        p_sys->p_info->sequence->picture_height;
    p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;

    if( p_sys->p_info->sequence->frame_period > 0 )
    {
        p_dec->fmt_out.video.i_frame_rate =
            (uint32_t)( (uint64_t)1001000000 * 27 /
                        p_sys->p_info->sequence->frame_period );
        p_dec->fmt_out.video.i_frame_rate_base = 1001;
    }

    p_dec->fmt_out.i_codec =
        ( p_sys->p_info->sequence->chroma_height <
          p_sys->p_info->sequence->height ) ?
        VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');

    /* Get a new picture */
    p_pic = p_dec->pf_vout_buffer_new( p_dec );

    if( p_pic == NULL ) return NULL;

    p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
        p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
    p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
        p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
    p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
        p_sys->p_info->current_picture->nb_fields : 2;

    p_dec->pf_picture_link( p_dec, p_pic );

    pp_buf[0] = p_pic->p[0].p_pixels;
    pp_buf[1] = p_pic->p[1].p_pixels;
    pp_buf[2] = p_pic->p[2].p_pixels;

    return p_pic;
}