mpv/libmpcodecs/vf_boxblur.c

/*
    Copyright (C) 2002 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <assert.h>

#include "config.h"
#include "mp_msg.h"

#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif

#include "img_format.h"
#include "mp_image.h"
#include "vf.h"


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

typedef struct FilterParam{
	int radius;
	int power;
}FilterParam;

struct vf_priv_s {
	FilterParam lumaParam;
	FilterParam chromaParam;
};


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


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

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

static inline void blur(uint8_t *dst, uint8_t *src, int w, int radius, int dstStep, int srcStep){
	int x;
	const int length= radius*2 + 1;
	const int inv= ((1<<16) + length/2)/length;

	int sum= 0;

	for(x=0; x<radius; x++){
		sum+= src[x*srcStep]<<1;
	}
	sum+= src[radius*srcStep];

	for(x=0; x<=radius; x++){
		sum+= src[(radius+x)*srcStep] - src[(radius-x)*srcStep];
		dst[x*dstStep]= (sum*inv + (1<<15))>>16;
	}

	for(; x<w-radius; x++){
		sum+= src[(radius+x)*srcStep] - src[(x-radius-1)*srcStep];
		dst[x*dstStep]= (sum*inv + (1<<15))>>16;
	}

	for(; x<w; x++){
		sum+= src[(2*w-radius-x-1)*srcStep] - src[(x-radius-1)*srcStep];
		dst[x*dstStep]= (sum*inv + (1<<15))>>16;
	}
}

static inline void blur2(uint8_t *dst, uint8_t *src, int w, int radius, int power, int dstStep, int srcStep){
	uint8_t temp[2][4096];
	uint8_t *a= temp[0], *b=temp[1];
	
	if(radius){
		blur(a, src, w, radius, 1, srcStep);
		for(; power>2; power--){
			uint8_t *c;
			blur(b, a, w, radius, 1, 1);
			c=a; a=b; b=c;
		}
		if(power>1)
			blur(dst, a, w, radius, dstStep, 1);
		else{
			int i;
			for(i=0; i<w; i++)
				dst[i*dstStep]= a[i];
		}
	}else{
		int i;
		for(i=0; i<w; i++)
			dst[i*dstStep]= src[i*srcStep];
	}
}

static void hBlur(uint8_t *dst, uint8_t *src, int w, int h, int dstStride, int srcStride, int radius, int power){
	int y;
	
	if(radius==0 && dst==src) return;
	
	for(y=0; y<h; y++){
		blur2(dst + y*dstStride, src + y*srcStride, w, radius, power, 1, 1);
	}
}

//FIXME optimize (x before y !!!)
static void vBlur(uint8_t *dst, uint8_t *src, int w, int h, int dstStride, int srcStride, int radius, int power){
	int x;
	
	if(radius==0 && dst==src) return;

	for(x=0; x<w; x++){
		blur2(dst + x, src + x, h, radius, power, dstStride, srcStride);
	}
}

static int put_image(struct vf_instance_s* vf, mp_image_t *mpi, double pts){
	int cw= mpi->w >> mpi->chroma_x_shift;
	int ch= mpi->h >> mpi->chroma_y_shift;

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

	assert(mpi->flags&MP_IMGFLAG_PLANAR);
	
	hBlur(dmpi->planes[0], mpi->planes[0], mpi->w,mpi->h, 
		dmpi->stride[0], mpi->stride[0], vf->priv->lumaParam.radius, vf->priv->lumaParam.power);
	hBlur(dmpi->planes[1], mpi->planes[1], cw,ch, 
		dmpi->stride[1], mpi->stride[1], vf->priv->chromaParam.radius, vf->priv->chromaParam.power);
	hBlur(dmpi->planes[2], mpi->planes[2], cw,ch, 
		dmpi->stride[2], mpi->stride[2], vf->priv->chromaParam.radius, vf->priv->chromaParam.power);
	
	vBlur(dmpi->planes[0], dmpi->planes[0], mpi->w,mpi->h, 
		dmpi->stride[0], dmpi->stride[0], vf->priv->lumaParam.radius, vf->priv->lumaParam.power);
	vBlur(dmpi->planes[1], dmpi->planes[1], cw,ch, 
		dmpi->stride[1], dmpi->stride[1], vf->priv->chromaParam.radius, vf->priv->chromaParam.power);
	vBlur(dmpi->planes[2], dmpi->planes[2], cw,ch, 
		dmpi->stride[2], dmpi->stride[2], vf->priv->chromaParam.radius, vf->priv->chromaParam.power);
    
	return vf_next_put_image(vf,dmpi, pts);
}

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

static int query_format(struct vf_instance_s* 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 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->priv=malloc(sizeof(struct vf_priv_s));
	memset(vf->priv, 0, sizeof(struct vf_priv_s));

	if(args==NULL) return 0;
	
	e=sscanf(args, "%d:%d:%d:%d",
		&vf->priv->lumaParam.radius,
		&vf->priv->lumaParam.power,
		&vf->priv->chromaParam.radius,
		&vf->priv->chromaParam.power
		);
	
	if(e==2){
		vf->priv->chromaParam.radius= vf->priv->lumaParam.radius;
		vf->priv->chromaParam.power = vf->priv->lumaParam.power;
	}else if(e!=4)
		return 0;

	if(vf->priv->lumaParam.radius < 0) return 0;
	if(vf->priv->chromaParam.radius < 0) return 0;
		
	return 1;
}

const vf_info_t vf_info_boxblur = {
    "box blur",
    "boxblur",
    "Michael Niedermayer",
    "",
    open,
    NULL
};

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