/*
 Copyright (C) 2006 Michael Niedermayer <michaelni@gmx.at>

 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*/

#include "hb.h"
#include "hbffmpeg.h"
#include "mpeg2dec/mpeg2.h"

#define SUPPRESS_AV_LOG

#define YADIF_MODE_DEFAULT     -1
#define YADIF_PARITY_DEFAULT   -1

#define MCDEINT_MODE_DEFAULT   -1
#define MCDEINT_QP_DEFAULT      1

#define ABS(a) ((a) > 0 ? (a) : (-(a)))
#define MIN3(a,b,c) MIN(MIN(a,b),c)
#define MAX3(a,b,c) MAX(MAX(a,b),c)

typedef struct yadif_arguments_s {
    uint8_t **dst;
    int parity;
    int tff;
    int stop;
} yadif_arguments_t;

struct hb_filter_private_s
{
    int              pix_fmt;
    int              width[3];
    int              height[3];

    int              yadif_mode;
    int              yadif_parity;
    int              yadif_ready;

    uint8_t        * yadif_ref[4][3];
    int              yadif_ref_stride[3];

    int              cpu_count;

    hb_thread_t    ** yadif_threads;        // Threads for Yadif - one per CPU
    hb_lock_t      ** yadif_begin_lock;     // Thread has work
    hb_lock_t      ** yadif_complete_lock;  // Thread has completed work
    yadif_arguments_t *yadif_arguments;     // Arguments to thread for work

    int              mcdeint_mode;
    int              mcdeint_qp;

    int              mcdeint_outbuf_size;
    uint8_t        * mcdeint_outbuf;
    AVCodecContext * mcdeint_avctx_enc;
    AVFrame        * mcdeint_frame;
    AVFrame        * mcdeint_frame_dec;

    AVPicture        pic_in;
    AVPicture        pic_out;
    hb_buffer_t *    buf_out[2];
    hb_buffer_t *    buf_settings;
};

hb_filter_private_t * hb_deinterlace_init( int pix_fmt,
                                           int width,
                                           int height,
                                           char * settings );

int hb_deinterlace_work( hb_buffer_t * buf_in,
                         hb_buffer_t ** buf_out,
                         int pix_fmt,
                         int width,
                         int height,
                         hb_filter_private_t * pv );

void hb_deinterlace_close( hb_filter_private_t * pv );

hb_filter_object_t hb_filter_deinterlace =
{
    FILTER_DEINTERLACE,
    "Deinterlace (ffmpeg or yadif/mcdeint)",
    NULL,
    hb_deinterlace_init,
    hb_deinterlace_work,
    hb_deinterlace_close,
};


static void yadif_store_ref( const uint8_t ** pic,
                             hb_filter_private_t * pv )
{
    memcpy( pv->yadif_ref[3],
            pv->yadif_ref[0],
            sizeof(uint8_t *)*3 );

    memmove( pv->yadif_ref[0],
             pv->yadif_ref[1],
             sizeof(uint8_t *)*3*3 );

    int i;
    for( i = 0; i < 3; i++ )
    {
        const uint8_t * src = pic[i];
        uint8_t * ref = pv->yadif_ref[2][i];

        int w = pv->width[i];
        int ref_stride = pv->yadif_ref_stride[i];

        int y;
        for( y = 0; y < pv->height[i]; y++ )
        {
            memcpy(ref, src, w);
            src = (uint8_t*)src + w;
            ref = (uint8_t*)ref + ref_stride;
        }
    }
}

static void yadif_filter_line( uint8_t *dst,
                               uint8_t *prev,
                               uint8_t *cur,
                               uint8_t *next,
                               int plane,
                               int parity,
                               hb_filter_private_t * pv )
{
    uint8_t *prev2 = parity ? prev : cur ;
    uint8_t *next2 = parity ? cur  : next;

    int w = pv->width[plane];
    int refs = pv->yadif_ref_stride[plane];

    int x;
    for( x = 0; x < w; x++)
    {
        int c              = cur[-refs];
        int d              = (prev2[0] + next2[0])>>1;
        int e              = cur[+refs];
        int temporal_diff0 = ABS(prev2[0] - next2[0]);
        int temporal_diff1 = ( ABS(prev[-refs] - c) + ABS(prev[+refs] - e) ) >> 1;
        int temporal_diff2 = ( ABS(next[-refs] - c) + ABS(next[+refs] - e) ) >> 1;
        int diff           = MAX3(temporal_diff0>>1, temporal_diff1, temporal_diff2);
        int spatial_pred   = (c+e)>>1;
        int spatial_score  = ABS(cur[-refs-1] - cur[+refs-1]) + ABS(c-e) +
                             ABS(cur[-refs+1] - cur[+refs+1]) - 1;

#define YADIF_CHECK(j)\
        {   int score = ABS(cur[-refs-1+j] - cur[+refs-1-j])\
                      + ABS(cur[-refs  +j] - cur[+refs  -j])\
                      + ABS(cur[-refs+1+j] - cur[+refs+1-j]);\
            if( score < spatial_score ){\
                spatial_score = score;\
                spatial_pred  = (cur[-refs  +j] + cur[+refs  -j])>>1;\

        YADIF_CHECK(-1) YADIF_CHECK(-2) }} }}
        YADIF_CHECK( 1) YADIF_CHECK( 2) }} }}

        if( pv->yadif_mode < 2 )
        {
            int b = (prev2[-2*refs] + next2[-2*refs])>>1;
            int f = (prev2[+2*refs] + next2[+2*refs])>>1;

            int max = MAX3(d-e, d-c, MIN(b-c, f-e));
            int min = MIN3(d-e, d-c, MAX(b-c, f-e));

            diff = MAX3( diff, min, -max );
        }

        if( spatial_pred > d + diff )
        {
            spatial_pred = d + diff;
        }
        else if( spatial_pred < d - diff )
        {
            spatial_pred = d - diff;
        }

        dst[0] = spatial_pred;

        dst++;
        cur++;
        prev++;
        next++;
        prev2++;
        next2++;
    }
}

typedef struct yadif_thread_arg_s {
    hb_filter_private_t *pv;
    int segment;
} yadif_thread_arg_t;

/*
 * deinterlace this segment of all three planes in a single thread.
 */
void yadif_filter_thread( void *thread_args_v )
{
    yadif_arguments_t *yadif_work = NULL;
    hb_filter_private_t * pv;
    int run = 1;
    int plane;
    int segment, segment_start, segment_stop;
    yadif_thread_arg_t *thread_args = thread_args_v;
    uint8_t **dst;
    int parity, tff, y, w, h, ref_stride, penultimate, ultimate;


    pv = thread_args->pv;
    segment = thread_args->segment;

    hb_log("Yadif Deinterlace thread started for segment %d", segment);

    while( run )
    {
        /*
         * Wait here until there is work to do. hb_lock() blocks until
         * render releases it to say that there is more work to do.
         */
        hb_lock( pv->yadif_begin_lock[segment] );

        yadif_work = &pv->yadif_arguments[segment];

        if( yadif_work->stop )
        {
            /*
             * No more work to do, exit this thread.
             */
            run = 0;
            continue;
        } 

        if( yadif_work->dst == NULL )
        {
            hb_error( "Thread started when no work available" );
            hb_snooze(500);
            continue;
        }
        
        /*
         * Process all three planes, but only this segment of it.
         */
        for( plane = 0; plane < 3; plane++)
        {

            dst = yadif_work->dst;
            parity = yadif_work->parity;
            tff = yadif_work->tff;
            w = pv->width[plane];
            h = pv->height[plane];
            penultimate = h -2;
            ultimate = h - 1;
            ref_stride = pv->yadif_ref_stride[plane];
            segment_start = ( h / pv->cpu_count ) * segment;
            if( segment == pv->cpu_count - 1 )
            {
                /*
                 * Final segment
                 */
                segment_stop = h;
            } else {
                segment_stop = ( h / pv->cpu_count ) * ( segment + 1 );
            }

            for( y = segment_start; y < segment_stop; y++ )
            {
                if( ( ( y ^ parity ) &  1 ) )
                {
                    /* This is the bottom field when TFF and vice-versa.
                       It's the field that gets filtered. Because yadif
                       needs 2 lines above and below the one being filtered,
                       we need to mirror the edges. When TFF, this means
                       replacing the 2nd line with a copy of the 1st,
                       and the last with the second-to-last.                  */
                    if( y > 1 && y < ( h -2 ) )
                    {
                        /* This isn't the top or bottom, proceed as normal to yadif. */
                        uint8_t *prev = &pv->yadif_ref[0][plane][y*ref_stride];
                        uint8_t *cur  = &pv->yadif_ref[1][plane][y*ref_stride];
                        uint8_t *next = &pv->yadif_ref[2][plane][y*ref_stride];
                        uint8_t *dst2 = &dst[plane][y*w];

                        yadif_filter_line( dst2, 
                                           prev, 
                                           cur, 
                                           next, 
                                           plane, 
                                           parity ^ tff, 
                                           pv );
                    }
                    else if( y == 0 )
                    {
                        /* BFF, so y0 = y1 */
                        memcpy( &dst[plane][y*w],
                                &pv->yadif_ref[1][plane][1*ref_stride],
                                w * sizeof(uint8_t) );
                    }
                    else if( y == 1 )
                    {
                        /* TFF, so y1 = y0 */
                        memcpy( &dst[plane][y*w],
                                &pv->yadif_ref[1][plane][0],
                                w * sizeof(uint8_t) );
                    }
                    else if( y == penultimate )
                    {
                        /* BFF, so penultimate y = ultimate y */
                        memcpy( &dst[plane][y*w],
                                &pv->yadif_ref[1][plane][ultimate*ref_stride],
                                w * sizeof(uint8_t) );
                    }
                    else if( y == ultimate )
                    {
                        /* TFF, so ultimate y = penultimate y */
                        memcpy( &dst[plane][y*w],
                                &pv->yadif_ref[1][plane][penultimate*ref_stride],
                                w * sizeof(uint8_t) );
                    }
                }
                else
                {
                    /* Preserve this field unfiltered */
                    memcpy( &dst[plane][y*w],
                            &pv->yadif_ref[1][plane][y*ref_stride],
                            w * sizeof(uint8_t) );
                }
            }
        }
        /*
         * Finished this segment, let everyone know.
         */
        hb_unlock( pv->yadif_complete_lock[segment] );
    }
    free( thread_args_v );
}


/*
 * threaded yadif - each thread deinterlaces a single segment of all
 * three planes. Where a segment is defined as the frame divided by
 * the number of CPUs.
 *
 * This function blocks until the frame is deinterlaced.
 */
static void yadif_filter( uint8_t ** dst,
                          int parity,
                          int tff,
                          hb_filter_private_t * pv )
{

    int segment;

    for( segment = 0; segment < pv->cpu_count; segment++ )
    {  
        /*
         * Setup the work for this plane.
         */
        pv->yadif_arguments[segment].parity = parity;
        pv->yadif_arguments[segment].tff = tff;
        pv->yadif_arguments[segment].dst = dst;

        /*
         * Let the thread for this plane know that we've setup work 
         * for it by releasing the begin lock (ensuring that the
         * complete lock is already locked so that we block when
         * we try to lock it again below).
         */
        hb_lock( pv->yadif_complete_lock[segment] );
        hb_unlock( pv->yadif_begin_lock[segment] );
    }

    /*
     * Wait until all three threads have completed by trying to get
     * the complete lock that we locked earlier for each thread, which
     * will block until that thread has completed the work on that
     * plane.
     */
    for( segment = 0; segment < pv->cpu_count; segment++ )
    {
        hb_lock( pv->yadif_complete_lock[segment] );
        hb_unlock( pv->yadif_complete_lock[segment] );
    }

    /*
     * Entire frame is now deinterlaced.
     */
}

static void mcdeint_filter( uint8_t ** dst,
                            uint8_t ** src,
                            int parity,
                            hb_filter_private_t * pv )
{
    int x, y, i;
    int out_size;

#ifdef SUPPRESS_AV_LOG
    /* TODO: temporarily change log level to suppress obnoxious debug output */
    int loglevel = av_log_get_level();
    av_log_set_level( AV_LOG_QUIET );
#endif

    for( i=0; i<3; i++ )
    {
        pv->mcdeint_frame->data[i] = src[i];
        pv->mcdeint_frame->linesize[i] = pv->width[i];
    }
    pv->mcdeint_avctx_enc->me_cmp     = FF_CMP_SAD;
    pv->mcdeint_avctx_enc->me_sub_cmp = FF_CMP_SAD;
    pv->mcdeint_frame->quality        = pv->mcdeint_qp * FF_QP2LAMBDA;

    out_size = avcodec_encode_video( pv->mcdeint_avctx_enc,
                                     pv->mcdeint_outbuf,
                                     pv->mcdeint_outbuf_size,
                                     pv->mcdeint_frame );

    pv->mcdeint_frame_dec = pv->mcdeint_avctx_enc->coded_frame;

    for( i = 0; i < 3; i++ )
    {
        int w    = pv->width[i];
        int h    = pv->height[i];
        int fils = pv->mcdeint_frame_dec->linesize[i];
        int srcs = pv->width[i];

        for( y = 0; y < h; y++ )
        {
            if( (y ^ parity) & 1 )
            {
                for( x = 0; x < w; x++ )
                {
                    if( (x-2)+(y-1)*w >= 0 && (x+2)+(y+1)*w < w*h )
                    {
                        uint8_t * filp =
                            &pv->mcdeint_frame_dec->data[i][x + y*fils];
                        uint8_t * srcp = &src[i][x + y*srcs];

                        int diff0 = filp[-fils] - srcp[-srcs];
                        int diff1 = filp[+fils] - srcp[+srcs];

                        int spatial_score =
                              ABS(srcp[-srcs-1] - srcp[+srcs-1])
                            + ABS(srcp[-srcs  ] - srcp[+srcs  ])
                            + ABS(srcp[-srcs+1] - srcp[+srcs+1]) - 1;

                        int temp = filp[0];

#define MCDEINT_CHECK(j)\
                        {   int score = ABS(srcp[-srcs-1+j] - srcp[+srcs-1-j])\
                                      + ABS(srcp[-srcs  +j] - srcp[+srcs  -j])\
                                      + ABS(srcp[-srcs+1+j] - srcp[+srcs+1-j]);\
                            if( score < spatial_score ) {\
                                spatial_score = score;\
                                diff0 = filp[-fils+j] - srcp[-srcs+j];\
                                diff1 = filp[+fils-j] - srcp[+srcs-j];

                        MCDEINT_CHECK(-1) MCDEINT_CHECK(-2) }} }}
                        MCDEINT_CHECK( 1) MCDEINT_CHECK( 2) }} }}

                        if(diff0 + diff1 > 0)
                        {
                            temp -= (diff0 + diff1 -
                                     ABS( ABS(diff0) - ABS(diff1) ) / 2) / 2;
                        }
                        else
                        {
                            temp -= (diff0 + diff1 +
                                     ABS( ABS(diff0) - ABS(diff1) ) / 2) / 2;
                        }

                        filp[0] = dst[i][x + y*w] =
                            temp > 255U ? ~(temp>>31) : temp;
                    }
                    else
                    {
                        dst[i][x + y*w] =
                            pv->mcdeint_frame_dec->data[i][x + y*fils];
                    }
                }
            }
        }

        for( y = 0; y < h; y++ )
        {
            if( !((y ^ parity) & 1) )
            {
                for( x = 0; x < w; x++ )
                {
                    pv->mcdeint_frame_dec->data[i][x + y*fils] =
                        dst[i][x + y*w]= src[i][x + y*srcs];
                }
            }
        }
    }

#ifdef SUPPRESS_AV_LOG
    /* TODO: restore previous log level */
    av_log_set_level(loglevel);
#endif
}

hb_filter_private_t * hb_deinterlace_init( int pix_fmt,
                                           int width,
                                           int height,
                                           char * settings )
{
    if( pix_fmt != PIX_FMT_YUV420P )
    {
        return 0;
    }

    hb_filter_private_t * pv = calloc( 1, sizeof(struct hb_filter_private_s) );

    pv->pix_fmt = pix_fmt;

    pv->width[0]  = width;
    pv->height[0] = height;
    pv->width[1]  = pv->width[2]  = width >> 1;
    pv->height[1] = pv->height[2] = height >> 1;

    pv->buf_out[0] = hb_video_buffer_init( width, height );
    pv->buf_out[1] = hb_video_buffer_init( width, height );
    pv->buf_settings = hb_buffer_init( 0 );

    pv->yadif_ready    = 0;
    pv->yadif_mode     = YADIF_MODE_DEFAULT;
    pv->yadif_parity   = YADIF_PARITY_DEFAULT;

    pv->mcdeint_mode   = MCDEINT_MODE_DEFAULT;
    pv->mcdeint_qp     = MCDEINT_QP_DEFAULT;

    if( settings )
    {
        sscanf( settings, "%d:%d:%d:%d",
                &pv->yadif_mode,
                &pv->yadif_parity,
                &pv->mcdeint_mode,
                &pv->mcdeint_qp );
    }

    pv->cpu_count = hb_get_cpu_count();

    /* Allocate yadif specific buffers */
    if( pv->yadif_mode >= 0 )
    {
        int i, j;
        for( i = 0; i < 3; i++ )
        {
            int is_chroma = !!i;
            int w = ((width   + 31) & (~31))>>is_chroma;
            int h = ((height+6+ 31) & (~31))>>is_chroma;

            pv->yadif_ref_stride[i] = w;

            for( j = 0; j < 3; j++ )
            {
                pv->yadif_ref[j][i] = malloc( w*h*sizeof(uint8_t) ) + 3*w;
            }
        }

        /*
         * Create yadif threads and locks.
         */
        pv->yadif_threads = malloc( sizeof( hb_thread_t* ) * pv->cpu_count );
        pv->yadif_begin_lock = malloc( sizeof( hb_lock_t * ) * pv->cpu_count );
        pv->yadif_complete_lock = malloc( sizeof( hb_lock_t * ) * pv->cpu_count );
        pv->yadif_arguments = malloc( sizeof( yadif_arguments_t ) * pv->cpu_count );

        for( i = 0; i < pv->cpu_count; i++ )
        {
            yadif_thread_arg_t *thread_args;

            thread_args = malloc( sizeof( yadif_thread_arg_t ) );

            if( thread_args ) {
                thread_args->pv = pv;
                thread_args->segment = i;

                pv->yadif_begin_lock[i] = hb_lock_init();
                pv->yadif_complete_lock[i] = hb_lock_init();

                /*
                 * Important to start off with the threads locked waiting
                 * on input.
                 */
                hb_lock( pv->yadif_begin_lock[i] );

                pv->yadif_arguments[i].stop = 0;
                pv->yadif_arguments[i].dst = NULL;
                
                pv->yadif_threads[i] = hb_thread_init( "yadif_filter_segment",
                                                       yadif_filter_thread,
                                                       thread_args,
                                                       HB_NORMAL_PRIORITY );
            } else {
                hb_error( "Yadif could not create threads" );
            }
        }
    }

    /* Allocate mcdeint specific buffers */
    if( pv->mcdeint_mode >= 0 )
    {
        avcodec_init();
        avcodec_register_all();

        AVCodec * enc = avcodec_find_encoder( CODEC_ID_SNOW );

        int i;
        for (i = 0; i < 3; i++ )
        {
            AVCodecContext * avctx_enc;

            avctx_enc = pv->mcdeint_avctx_enc = avcodec_alloc_context();

            avctx_enc->width                    = width;
            avctx_enc->height                   = height;
            avctx_enc->time_base                = (AVRational){1,25};  // meaningless
            avctx_enc->gop_size                 = 300;
            avctx_enc->max_b_frames             = 0;
            avctx_enc->pix_fmt                  = PIX_FMT_YUV420P;
            avctx_enc->flags                    = CODEC_FLAG_QSCALE | CODEC_FLAG_LOW_DELAY;
            avctx_enc->strict_std_compliance    = FF_COMPLIANCE_EXPERIMENTAL;
            avctx_enc->global_quality           = 1;
            avctx_enc->flags2                   = CODEC_FLAG2_MEMC_ONLY;
            avctx_enc->me_cmp                   = FF_CMP_SAD; //SSE;
            avctx_enc->me_sub_cmp               = FF_CMP_SAD; //SSE;
            avctx_enc->mb_cmp                   = FF_CMP_SSE;

            switch( pv->mcdeint_mode )
            {
                case 3:
                    avctx_enc->refs = 3;
                case 2:
                    avctx_enc->me_method = ME_UMH;
                case 1:
                    avctx_enc->flags |= CODEC_FLAG_4MV;
                    avctx_enc->dia_size =2;
                case 0:
                    avctx_enc->flags |= CODEC_FLAG_QPEL;
            }

            hb_avcodec_open(avctx_enc, enc);
        }

        pv->mcdeint_frame       = avcodec_alloc_frame();
        pv->mcdeint_outbuf_size = width * height * 10;
        pv->mcdeint_outbuf      = malloc( pv->mcdeint_outbuf_size );
    }

    return pv;
}

void hb_deinterlace_close( hb_filter_private_t * pv )
{
    if( !pv )
    {
        return;
    }

    /* Cleanup frame buffers */
    if( pv->buf_out[0] )
    {
        hb_buffer_close( &pv->buf_out[0] );
    }
    if( pv->buf_out[1] )
    {
        hb_buffer_close( &pv->buf_out[1] );
    }
    if (pv->buf_settings )
    {
        hb_buffer_close( &pv->buf_settings );
    }

    /* Cleanup yadif specific buffers */
    if( pv->yadif_mode >= 0 )
    {
        int i;
        for( i = 0; i<3*3; i++ )
        {
            uint8_t **p = &pv->yadif_ref[i%3][i/3];
            if (*p)
            {
                free( *p - 3*pv->yadif_ref_stride[i/3] );
                *p = NULL;
            }
        }

        for( i = 0; i < pv->cpu_count; i++)
        {
            /*
             * Tell each yadif thread to stop, and then cleanup.
             */
            pv->yadif_arguments[i].stop = 1;
            hb_unlock(  pv->yadif_begin_lock[i] );

            hb_thread_close( &pv->yadif_threads[i] );
            hb_lock_close( &pv->yadif_begin_lock[i] );
            hb_lock_close( &pv->yadif_complete_lock[i] );
        }
        
        /*
         * free memory for yadif structs
         */
        free( pv->yadif_threads );
        free( pv->yadif_begin_lock );
        free( pv->yadif_complete_lock );
        free( pv->yadif_arguments );
    }

    /* Cleanup mcdeint specific buffers */
    if( pv->mcdeint_mode >= 0 )
    {
        if( pv->mcdeint_avctx_enc )
        {
            hb_avcodec_close( pv->mcdeint_avctx_enc );
            av_freep( &pv->mcdeint_avctx_enc );
        }
        if( pv->mcdeint_outbuf )
        {
            free( pv->mcdeint_outbuf );
        }
    }

    free( pv );
}

int hb_deinterlace_work( hb_buffer_t * buf_in,
                         hb_buffer_t ** buf_out,
                         int pix_fmt,
                         int width,
                         int height,
                         hb_filter_private_t * pv )
{
    if( !pv ||
        pix_fmt != pv->pix_fmt ||
        width   != pv->width[0] ||
        height  != pv->height[0] )
    {
        return FILTER_FAILED;
    }

    avpicture_fill( &pv->pic_in, buf_in->data,
                    pix_fmt, width, height );

    /* Use libavcodec deinterlace if yadif_mode < 0 */
    if( pv->yadif_mode < 0 )
    {
        avpicture_fill( &pv->pic_out, pv->buf_out[0]->data,
                        pix_fmt, width, height );

        avpicture_deinterlace( &pv->pic_out, &pv->pic_in,
                               pix_fmt, width, height );

        hb_buffer_copy_settings( pv->buf_out[0], buf_in );

        *buf_out = pv->buf_out[0];

        return FILTER_OK;
    }

    /* Determine if top-field first layout */
    int tff;
    if( pv->yadif_parity < 0 )
    {
        tff = !!(buf_in->flags & PIC_FLAG_TOP_FIELD_FIRST);
    }
    else
    {
        tff = (pv->yadif_parity & 1) ^ 1;
    }

    /* Store current frame in yadif cache */
    yadif_store_ref( (const uint8_t**)pv->pic_in.data, pv );

    /* If yadif is not ready, store another ref and return FILTER_DELAY */
    if( pv->yadif_ready == 0 )
    {
        yadif_store_ref( (const uint8_t**)pv->pic_in.data, pv );

        hb_buffer_copy_settings( pv->buf_settings, buf_in );

        /* don't let 'work_loop' send a chapter mark upstream */
        buf_in->new_chap  = 0;

        pv->yadif_ready = 1;

        return FILTER_DELAY;
    }

    /* Perform yadif and mcdeint filtering */
    int frame;
    for( frame = 0; frame <= (pv->yadif_mode & 1); frame++ )
    {
        int parity = frame ^ tff ^ 1;

        avpicture_fill( &pv->pic_out, pv->buf_out[!(frame^1)]->data,
                        pix_fmt, width, height );

        yadif_filter( pv->pic_out.data, parity, tff, pv );

        if( pv->mcdeint_mode >= 0 )
        {
            avpicture_fill( &pv->pic_in,  pv->buf_out[(frame^1)]->data,
                            pix_fmt, width, height );

            mcdeint_filter( pv->pic_in.data, pv->pic_out.data, parity, pv );

            *buf_out = pv->buf_out[ (frame^1)];
        }
        else
        {
            *buf_out = pv->buf_out[!(frame^1)];
        }
    }

    /* Copy buffered settings to output buffer settings */
    hb_buffer_copy_settings( *buf_out, pv->buf_settings );

    /* Replace buffered settings with input buffer settings */
    hb_buffer_copy_settings( pv->buf_settings, buf_in );

    /* don't let 'work_loop' send a chapter mark upstream */
    buf_in->new_chap  = 0;

    return FILTER_OK;
}


