// test_avfilter.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"


/**
* 最简单的基于FFmpeg的AVFilter例子 - 纯净版
* Simplest FFmpeg AVfilter Example - Pure
*
* 雷霄骅 Lei Xiaohua
* leixiaohua1020@126.com
* 中国传媒大学/数字电视技术
* Communication University of China / Digital TV Technology
*
* 本程序使用FFmpeg的AVfilter实现了YUV像素数据的滤镜处理功能。
* 可以给YUV数据添加各种特效功能。
* 是最简单的FFmpeg的AVFilter方面的教程。
* 适合FFmpeg的初学者。
*
* This software uses FFmpeg's AVFilter to process YUV raw data.
* It can add many excellent effect to YUV data.
* It's the simplest example based on FFmpeg's AVFilter.
* Suitable for beginner of FFmpeg
*
*/
#include <stdio.h>

#define __STDC_CONSTANT_MACROS

#ifdef _WIN32
#define snprintf _snprintf
//Windows
extern "C"
{
#include "libavfilter/avfiltergraph.h"
#include "libavfilter/buffersink.h"
#include "libavfilter/buffersrc.h"
#include "libavutil/avutil.h"
#include "libavutil/imgutils.h"
};
#else
//Linux...
#ifdef __cplusplus
extern "C"
{
#endif
#include <libavfilter/avfiltergraph.h>
#include <libavfilter/buffersink.h>
#include <libavfilter/buffersrc.h>
#include <libavutil/avutil.h>
#include <libavutil/imgutils.h>
#ifdef __cplusplus
};
#endif
#endif


#pragma comment(lib,"avcodec.lib")
#pragma comment(lib,"avformat.lib")
#pragma comment(lib,"avutil.lib")
#pragma comment(lib,"avfilter.lib")
#pragma comment(lib,"swscale.lib")
#pragma comment(lib,"SDL2.lib")
#pragma comment(lib,"SDL2main.lib")

int main(int argc, char* argv[])
{
  getchar();

  int ret;
  AVFrame *frame_in;
  AVFrame *frame_out;
  unsigned char *frame_buffer_in;
  unsigned char *frame_buffer_out;

  AVFilterContext *buffersink_ctx;
  AVFilterContext *buffersrc_ctx;
  AVFilterGraph *filter_graph;
  static int video_stream_index = -1;

  //Input YUV
  FILE *fp_in = fopen("trans.yuv", "rb+");
  if (fp_in == NULL) {
    printf("Error open input file.\n");
    return -1;
  }
  int in_width = 1588;
  int in_height = 900;

  //Output YUV
  FILE *fp_out = fopen("output.yuv", "wb+");
  if (fp_out == NULL) {
    printf("Error open output file.\n");
    return -1;
  }

  //const char *filter_descr = "lutyuv='u=128:v=128'";
  //const char *filter_descr = "boxblur";
  //const char *filter_descr = "hflip";
  //const char *filter_descr = "hue='h=60:s=-3'";
  //const char *filter_descr = "crop=2/3*in_w:2/3*in_h";
  //const char *filter_descr = "drawbox=x=100:y=100:w=100:h=100:color=pink@0.5";
  const char *filter_descr = "drawtext=fontfile=arial.ttf:fontcolor=red:fontsize=30:text='Lei Xiaohua':x=50:y=50";

  avfilter_register_all();

  char args[512];
  AVFilter *buffersrc = avfilter_get_by_name("buffer");
  AVFilter *buffersink = avfilter_get_by_name("buffersink");
  AVFilterInOut *outputs = avfilter_inout_alloc();
  AVFilterInOut *inputs = avfilter_inout_alloc();
  enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE };
  AVBufferSinkParams *buffersink_params;

  filter_graph = avfilter_graph_alloc();

  /* buffer video source: the decoded frames from the decoder will be inserted here. */
  snprintf(args, sizeof(args),
    "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
    in_width, in_height, AV_PIX_FMT_YUV420P,
    1, 25, 1, 1);

  ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
    args, NULL, filter_graph);
  if (ret < 0) {
    printf("Cannot create buffer source\n");
    return ret;
  }

  /* buffer video sink: to terminate the filter chain. */
  buffersink_params = av_buffersink_params_alloc();
  buffersink_params->pixel_fmts = pix_fmts;
  ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
    NULL, buffersink_params, filter_graph);
  av_free(buffersink_params);
  if (ret < 0) {
    printf("Cannot create buffer sink\n");
    return ret;
  }

  /* Endpoints for the filter graph. */
  outputs->name = av_strdup("in");
  outputs->filter_ctx = buffersrc_ctx;
  outputs->pad_idx = 0;
  outputs->next = NULL;

  inputs->name = av_strdup("out");
  inputs->filter_ctx = buffersink_ctx;
  inputs->pad_idx = 0;
  inputs->next = NULL;

  if ((ret = avfilter_graph_parse_ptr(filter_graph, filter_descr,
    &inputs, &outputs, NULL)) < 0)
    return ret;

  if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0)
    return ret;

  frame_in = av_frame_alloc();
  frame_buffer_in = (unsigned char *)av_malloc(av_image_get_buffer_size(AV_PIX_FMT_YUV420P, in_width, in_height, 1));
  av_image_fill_arrays(frame_in->data, frame_in->linesize, frame_buffer_in,
    AV_PIX_FMT_YUV420P, in_width, in_height, 1);

  frame_out = av_frame_alloc();
  frame_buffer_out = (unsigned char *)av_malloc(av_image_get_buffer_size(AV_PIX_FMT_YUV420P, in_width, in_height, 1));
  av_image_fill_arrays(frame_out->data, frame_out->linesize, frame_buffer_out,
    AV_PIX_FMT_YUV420P, in_width, in_height, 1);

  frame_in->width = in_width;
  frame_in->height = in_height;
  frame_in->format = AV_PIX_FMT_YUV420P;

  while (1) {

    if (fread(frame_buffer_in, 1, in_width*in_height * 3 / 2, fp_in) != in_width*in_height * 3 / 2) {
      break;
    }
    //input Y,U,V
    frame_in->data[0] = frame_buffer_in;
    frame_in->data[1] = frame_buffer_in + in_width*in_height;
    frame_in->data[2] = frame_buffer_in + in_width*in_height * 5 / 4;

    if (av_buffersrc_add_frame(buffersrc_ctx, frame_in) < 0) {
      printf("Error while add frame.\n");
      break;
    }

    /* pull filtered pictures from the filtergraph */
    ret = av_buffersink_get_frame(buffersink_ctx, frame_out);
    if (ret < 0)
      break;

    //output Y,U,V
    if (frame_out->format == AV_PIX_FMT_YUV420P) {
      for (int i = 0; i<frame_out->height; i++) {
        fwrite(frame_out->data[0] + frame_out->linesize[0] * i, 1, frame_out->width, fp_out);
      }
      for (int i = 0; i<frame_out->height / 2; i++) {
        fwrite(frame_out->data[1] + frame_out->linesize[1] * i, 1, frame_out->width / 2, fp_out);
      }
      for (int i = 0; i<frame_out->height / 2; i++) {
        fwrite(frame_out->data[2] + frame_out->linesize[2] * i, 1, frame_out->width / 2, fp_out);
      }
    }
    printf("Process 1 frame!\n");
    av_frame_unref(frame_out);
  }

  fclose(fp_in);
  fclose(fp_out);

  av_frame_free(&frame_in);
  av_frame_free(&frame_out);
  avfilter_graph_free(&filter_graph);

  return 0;
}