ffmpeg/libavfilter/libmpcodecs/vf_smartblur.c

/*
 * Copyright (C) 2002 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of MPlayer.
 *
 * MPlayer 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.
 *
 * MPlayer 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 MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <assert.h>

#include "mp_msg.h"
#include "libavutil/avutil.h"
#include "img_format.h"
#include "mp_image.h"
#include "vf.h"
#include "libswscale/swscale.h"
#include "vf_scale.h"

//===========================================================================//

typedef struct FilterParam{
    float radius;
    float strength;
    int threshold;
    float quality;
    struct SwsContext *filterContext;
}FilterParam;

struct vf_priv_s {
    FilterParam luma;
    FilterParam chroma;
};


/***************************************************************************/

//FIXME stupid code duplication
static void getSubSampleFactors(int *h, int *v, int format){
    switch(format){
    default:
        assert(0);
    case IMGFMT_YV12:
    case IMGFMT_I420:
        *h=1;
        *v=1;
        break;
    case IMGFMT_YVU9:
        *h=2;
        *v=2;
        break;
    case IMGFMT_444P:
        *h=0;
        *v=0;
        break;
    case IMGFMT_422P:
        *h=1;
        *v=0;
        break;
    case IMGFMT_411P:
        *h=2;
        *v=0;
        break;
    }
}

static int allocStuff(FilterParam *f, int width, int height){
    SwsVector *vec;
    SwsFilter swsF;

    vec = sws_getGaussianVec(f->radius, f->quality);
    sws_scaleVec(vec, f->strength);
    vec->coeff[vec->length/2]+= 1.0 - f->strength;
    swsF.lumH= swsF.lumV= vec;
    swsF.chrH= swsF.chrV= NULL;
    f->filterContext= sws_getContext(
        width, height, PIX_FMT_GRAY8, width, height, PIX_FMT_GRAY8, SWS_BICUBIC, &swsF, NULL, NULL);

    sws_freeVec(vec);

    return 0;
}

static int config(struct vf_instance *vf,
    int width, int height, int d_width, int d_height,
    unsigned int flags, unsigned int outfmt){

    int sw, sh;

    allocStuff(&vf->priv->luma, width, height);

    getSubSampleFactors(&sw, &sh, outfmt);
    allocStuff(&vf->priv->chroma, width>>sw, height>>sh);

    return vf_next_config(vf,width,height,d_width,d_height,flags,outfmt);
}

static void freeBuffers(FilterParam *f){
    if(f->filterContext) sws_freeContext(f->filterContext);
    f->filterContext=NULL;
}

static void uninit(struct vf_instance *vf){
    if(!vf->priv) return;

    freeBuffers(&vf->priv->luma);
    freeBuffers(&vf->priv->chroma);

    free(vf->priv);
    vf->priv=NULL;
}

static inline void blur(uint8_t *dst, uint8_t *src, int w, int h, int dstStride, int srcStride, FilterParam *fp){
    int x, y;
    FilterParam f= *fp;
    const uint8_t* const srcArray[MP_MAX_PLANES] = {src};
    uint8_t *dstArray[MP_MAX_PLANES]= {dst};
    int srcStrideArray[MP_MAX_PLANES]= {srcStride};
    int dstStrideArray[MP_MAX_PLANES]= {dstStride};

    sws_scale(f.filterContext, srcArray, srcStrideArray, 0, h, dstArray, dstStrideArray);

    if(f.threshold > 0){
        for(y=0; y<h; y++){
            for(x=0; x<w; x++){
                const int orig= src[x + y*srcStride];
                const int filtered= dst[x + y*dstStride];
                const int diff= orig - filtered;

                if(diff > 0){
                    if(diff > 2*f.threshold){
                        dst[x + y*dstStride]= orig;
                    }else if(diff > f.threshold){
                        dst[x + y*dstStride]= filtered + diff - f.threshold;
                    }
                }else{
                    if(-diff > 2*f.threshold){
                        dst[x + y*dstStride]= orig;
                    }else if(-diff > f.threshold){
                        dst[x + y*dstStride]= filtered + diff + f.threshold;
                    }
                }
            }
        }
    }else if(f.threshold < 0){
        for(y=0; y<h; y++){
            for(x=0; x<w; x++){
                const int orig= src[x + y*srcStride];
                const int filtered= dst[x + y*dstStride];
                const int diff= orig - filtered;

                if(diff > 0){
                    if(diff > -2*f.threshold){
                    }else if(diff > -f.threshold){
                        dst[x + y*dstStride]= orig - diff - f.threshold;
                    }else
                        dst[x + y*dstStride]= orig;
                }else{
                    if(diff < 2*f.threshold){
                    }else if(diff < f.threshold){
                        dst[x + y*dstStride]= orig - diff + f.threshold;
                    }else
                        dst[x + y*dstStride]= orig;
                }
            }
        }
    }
}

static int put_image(struct vf_instance *vf, mp_image_t *mpi, double pts){
    int cw= mpi->w >> mpi->chroma_x_shift;
    int ch= mpi->h >> mpi->chroma_y_shift;
    int threshold = vf->priv->luma.threshold || vf->priv->chroma.threshold;

    mp_image_t *dmpi=vf_get_image(vf->next,mpi->imgfmt,
        MP_IMGTYPE_TEMP, MP_IMGFLAG_ACCEPT_STRIDE|
        (threshold ? MP_IMGFLAG_READABLE : 0),
        mpi->w,mpi->h);

    assert(mpi->flags&MP_IMGFLAG_PLANAR);

    blur(dmpi->planes[0], mpi->planes[0], mpi->w,mpi->h, dmpi->stride[0], mpi->stride[0], &vf->priv->luma);
    blur(dmpi->planes[1], mpi->planes[1], cw    , ch   , dmpi->stride[1], mpi->stride[1], &vf->priv->chroma);
    blur(dmpi->planes[2], mpi->planes[2], cw    , ch   , dmpi->stride[2], mpi->stride[2], &vf->priv->chroma);

    return vf_next_put_image(vf,dmpi, pts);
}

//===========================================================================//

static int query_format(struct vf_instance *vf, unsigned int fmt){
    switch(fmt)
    {
    case IMGFMT_YV12:
    case IMGFMT_I420:
    case IMGFMT_IYUV:
    case IMGFMT_YVU9:
    case IMGFMT_444P:
    case IMGFMT_422P:
    case IMGFMT_411P:
        return vf_next_query_format(vf, fmt);
    }
    return 0;
}

static int vf_open(vf_instance_t *vf, char *args){
    int e;

    vf->config=config;
    vf->put_image=put_image;
//    vf->get_image=get_image;
    vf->query_format=query_format;
    vf->uninit=uninit;
    vf->priv=malloc(sizeof(struct vf_priv_s));
    memset(vf->priv, 0, sizeof(struct vf_priv_s));

    if(args==NULL) return 0;

    e=sscanf(args, "%f:%f:%d:%f:%f:%d",
        &vf->priv->luma.radius,
        &vf->priv->luma.strength,
        &vf->priv->luma.threshold,
        &vf->priv->chroma.radius,
        &vf->priv->chroma.strength,
        &vf->priv->chroma.threshold
        );

    vf->priv->luma.quality = vf->priv->chroma.quality= 3.0;

    if(e==3){
        vf->priv->chroma.radius= vf->priv->luma.radius;
        vf->priv->chroma.strength= vf->priv->luma.strength;
        vf->priv->chroma.threshold = vf->priv->luma.threshold;
    }else if(e!=6)
        return 0;

    return 1;
}

const vf_info_t vf_info_smartblur = {
    "smart blur",
    "smartblur",
    "Michael Niedermayer",
    "",
    vf_open,
    NULL
};

//===========================================================================//