/*
 * Copyright (c) 2010 Stefano Sabatini
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * libopencv wrapper functions
 */

#include <opencv/cv.h>
#include <opencv/cxtypes.h>
#include "avfilter.h"

static void fill_iplimage_from_picref(IplImage *img, const AVFilterBufferRef *picref, enum PixelFormat pixfmt)
{
    IplImage *tmpimg;
    int depth, channels_nb;

    if      (pixfmt == PIX_FMT_GRAY8) { depth = IPL_DEPTH_8U;  channels_nb = 1; }
    else if (pixfmt == PIX_FMT_BGRA)  { depth = IPL_DEPTH_8U;  channels_nb = 4; }
    else if (pixfmt == PIX_FMT_BGR24) { depth = IPL_DEPTH_8U;  channels_nb = 3; }
    else return;

    tmpimg = cvCreateImageHeader((CvSize){picref->video->w, picref->video->h}, depth, channels_nb);
    *img = *tmpimg;
    img->imageData = img->imageDataOrigin = picref->data[0];
    img->dataOrder = IPL_DATA_ORDER_PIXEL;
    img->origin    = IPL_ORIGIN_TL;
    img->widthStep = picref->linesize[0];
}

static void fill_picref_from_iplimage(AVFilterBufferRef *picref, const IplImage *img, enum PixelFormat pixfmt)
{
    picref->linesize[0] = img->widthStep;
    picref->data[0]     = img->imageData;
}

static int query_formats(AVFilterContext *ctx)
{
    static const enum PixelFormat pix_fmts[] = {
        PIX_FMT_BGR24, PIX_FMT_BGRA, PIX_FMT_GRAY8, PIX_FMT_NONE
    };

    avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
    return 0;
}

static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }

#if CONFIG_OCV_SMOOTH_FILTER

typedef struct {
    int type;
    int    param1, param2;
    double param3, param4;
} SmoothContext;

static av_cold int smooth_init(AVFilterContext *ctx, const char *args, void *opaque)
{
    SmoothContext *smooth = ctx->priv;
    char type_str[128] = "gaussian";

    smooth->param1 = 3;
    smooth->param2 = 0;
    smooth->param3 = 0.0;
    smooth->param4 = 0.0;

    if (args)
        sscanf(args, "%127[^:]:%d:%d:%lf:%lf", type_str, &smooth->param1, &smooth->param2, &smooth->param3, &smooth->param4);

    if      (!strcmp(type_str, "blur"         )) smooth->type = CV_BLUR;
    else if (!strcmp(type_str, "blur_no_scale")) smooth->type = CV_BLUR_NO_SCALE;
    else if (!strcmp(type_str, "median"       )) smooth->type = CV_MEDIAN;
    else if (!strcmp(type_str, "gaussian"     )) smooth->type = CV_GAUSSIAN;
    else if (!strcmp(type_str, "bilateral"    )) smooth->type = CV_BILATERAL;
    else {
        av_log(ctx, AV_LOG_ERROR, "Smoothing type '%s' unknown\n.", type_str);
        return AVERROR(EINVAL);
    }

    if (smooth->param1 < 0 || !(smooth->param1%2)) {
        av_log(ctx, AV_LOG_ERROR,
               "Invalid value '%d' for param1, it has to be a positive odd number\n",
               smooth->param1);
        return AVERROR(EINVAL);
    }
    if ((smooth->type == CV_BLUR || smooth->type == CV_BLUR_NO_SCALE || smooth->type == CV_GAUSSIAN) &&
        (smooth->param2 < 0 || (smooth->param2 && !(smooth->param2%2)))) {
        av_log(ctx, AV_LOG_ERROR,
               "Invalid value '%d' for param2, it has to be zero or a positive odd number\n",
               smooth->param2);
        return AVERROR(EINVAL);
    }

    av_log(ctx, AV_LOG_INFO, "type:%s param1:%d param2:%d param3:%f param4:%f\n",
           type_str, smooth->param1, smooth->param2, smooth->param3, smooth->param4);
    return 0;
}

static void smooth_end_frame(AVFilterLink *inlink)
{
    SmoothContext *smooth = inlink->dst->priv;
    AVFilterLink *outlink = inlink->dst->outputs[0];
    AVFilterBufferRef *inpicref  = inlink ->cur_buf;
    AVFilterBufferRef *outpicref = outlink->out_buf;
    IplImage inimg, outimg;

    fill_iplimage_from_picref(&inimg , inpicref , inlink->format);
    fill_iplimage_from_picref(&outimg, outpicref, inlink->format);
    cvSmooth(&inimg, &outimg, smooth->type, smooth->param1, smooth->param2, smooth->param3, smooth->param4);
    fill_picref_from_iplimage(outpicref, &outimg, inlink->format);

    avfilter_unref_buffer(inpicref);
    avfilter_draw_slice(outlink, 0, outlink->h, 1);
    avfilter_end_frame(outlink);
    avfilter_unref_buffer(outpicref);
}

AVFilter avfilter_vf_ocv_smooth = {
    .name        = "ocv_smooth",
    .description = NULL_IF_CONFIG_SMALL("Apply smooth transform using libopencv."),

    .priv_size = sizeof(SmoothContext),

    .query_formats = query_formats,
    .init = smooth_init,

    .inputs    = (AVFilterPad[]) {{ .name             = "default",
                                    .type             = AVMEDIA_TYPE_VIDEO,
                                    .draw_slice       = null_draw_slice,
                                    .end_frame        = smooth_end_frame,
                                    .min_perms        = AV_PERM_READ },
                                  { .name = NULL}},

    .outputs   = (AVFilterPad[]) {{ .name             = "default",
                                    .type             = AVMEDIA_TYPE_VIDEO, },
                                  { .name = NULL}},
};

#endif /* CONFIG_OCV_SMOOTH_FILTER */