
/*!
 ************************************************************************
 * \file output.c
 *
 * \brief
 *    Output an image and Trance support
 *
 * \author
 *    Main contributors (see contributors.h for copyright, address and affiliation details)
 *    - Karsten Suehring               <suehring@hhi.de>
 ************************************************************************
 */

#include "contributors.h"

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

#ifdef WIN32
#include <io.h>
#else
#include <unistd.h>
#endif

#include "global.h"
#include "image.h"

void write_out_picture(StorablePicture *p, int p_out);

FrameStore* out_buffer;


/*!
 ************************************************************************
 * \brief
 *      checks if the System is big- or little-endian
 * \return
 *      0, little-endian (e.g. Intel architectures)
 *      1, big-endian (e.g. SPARC, MIPS, PowerPC)
 ************************************************************************
 */
int testEndian()
{
  short s;
  byte *p;

  p=(byte*)&s;

  s=1;

  return (*p==0);
}


/*!
 ************************************************************************
 * \brief
 *    Convert image plane to temporary buffer for file writing
 ************************************************************************
 */
void img2buf ( imgpel** imgX,            //!< Pointer to image plane
               unsigned char* buf,       //!< Buffer for file output
               int size_x,               //!< horizontal size of picture
               int size_y,               //!< vertical size of picture
               int symbol_size_in_bytes, //!< number of bytes in file used to represent a pel
               int crop_left,            //!< pixels to crop from left
               int crop_right,           //!< pixels to crop from right
               int crop_top,             //!< pixels to crop from top
               int crop_bottom           //!< pixels to crop from bottom
               )
{
  int i,j;

  int twidth  = size_x - crop_left - crop_right;
  int theight = size_y - crop_top - crop_bottom;

  int size = 0;

  unsigned char  ui8;
  unsigned short tmp16, ui16;
  unsigned long  tmp32, ui32;

  if (( sizeof(char) == sizeof (imgpel)) && ( sizeof(char) == symbol_size_in_bytes))
  {
    // imgpel == pixel_in_file == 1 byte -> simple copy
    for(i=0;i<theight;i++)
      memcpy(buf+crop_left+(i*twidth),&(imgX[i+crop_top][crop_left]), twidth);
    
  }
  else
  {
    // sizeof (imgpel) > sizeof(char)
    if (testEndian())
    {
      // big endian
      switch (symbol_size_in_bytes)
      {
      case 1:
        {
          for(i=crop_top;i<size_y-crop_bottom;i++)
            for(j=crop_left;j<size_x-crop_right;j++)
            {
              ui8 = (unsigned char) (imgX[i][j]);
              buf[(j-crop_left+((i-crop_top)*(twidth)))] = ui8;
            }
          break;
        }
      case 2:
        {
          for(i=crop_top;i<size_y-crop_bottom;i++)
            for(j=crop_left;j<size_x-crop_right;j++)
            {
              tmp16 = (unsigned short) (imgX[i][j]);
              ui16  = (tmp16 >> 8) | ((tmp16&0xFF)<<8);
              memcpy(buf+((j-crop_left+((i-crop_top)*(twidth)))*2),&(ui16), 2);
            }
          break;
        }
      case 4:
        {
          for(i=crop_top;i<size_y-crop_bottom;i++)
            for(j=crop_left;j<size_x-crop_right;j++)
            {
              tmp32 = (unsigned long) (imgX[i][j]);
              ui32  = ((tmp32&0xFF00)<<8) | ((tmp32&0xFF)<<24) | ((tmp32&0xFF0000)>>8) | ((tmp32&0xFF000000)>>24);
              memcpy(buf+((j-crop_left+((i-crop_top)*(twidth)))*4),&(ui32), 4);
            }
          break;
        }
      default:
        {
           error ("writing only to formats of 8, 16 or 32 bit allowed on big endian architecture", 500);
           break;
        }
      }

    }
    else
    {
      // little endian
      if (sizeof (imgpel) < symbol_size_in_bytes)
      {
        // this should not happen. we should not have smaller imgpel than our source material.
        size = sizeof (imgpel);
        // clear buffer
        memset (buf, 0, (twidth*theight*symbol_size_in_bytes));
      }
      else
      {
        size = symbol_size_in_bytes;
      }

      for(i=crop_top;i<size_y-crop_bottom;i++)
        for(j=crop_left;j<size_x-crop_right;j++)
        {
          memcpy(buf+((j-crop_left+((i-crop_top)*(twidth)))*symbol_size_in_bytes),&(imgX[i][j]), size);
        }

    }
  }
}

/*!
 ************************************************************************
 * \brief
 *    Writes out a storable picture without doing any output modifications
 * \param p
 *    Picture to be written
 * \param p_out
 *    Output file
 * \param real_structure
 *    real picture structure
 ************************************************************************
 */
void write_picture(StorablePicture *p, int p_out, int real_structure)
{
  write_out_picture(p, p_out);
}

/*!
 ************************************************************************
 * \brief
 *    Writes out a storable picture
 * \param p
 *    Picture to be written
 * \param p_out
 *    Output file
 ************************************************************************
 */
void write_out_picture(StorablePicture *p, int p_out)
{
  int SubWidthC  [4]= { 1, 2, 2, 1};
  int SubHeightC [4]= { 1, 2, 1, 1};

  int crop_left, crop_right, crop_top, crop_bottom;
  int symbol_size_in_bytes = img->pic_unit_size_on_disk/8;
  Boolean rgb_output = (input->rgb_input_flag && input->yuv_format==3);
  unsigned char *buf;

  if (p->non_existing)
    return;

  if (p->frame_cropping_flag)
  {
    crop_left   = SubWidthC[p->chroma_format_idc] * p->frame_cropping_rect_left_offset;
    crop_right  = SubWidthC[p->chroma_format_idc] * p->frame_cropping_rect_right_offset;
    crop_top    = SubHeightC[p->chroma_format_idc]*( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_top_offset;
    crop_bottom = SubHeightC[p->chroma_format_idc]*( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_bottom_offset;
  }
  else
  {
    crop_left = crop_right = crop_top = crop_bottom = 0;
  }

  //printf ("write frame size: %dx%d\n", p->size_x-crop_left-crop_right,p->size_y-crop_top-crop_bottom );

  // KS: this buffer should actually be allocated only once, but this is still much faster than the previous version
  buf = malloc (p->size_x*p->size_y*symbol_size_in_bytes);
  if (NULL==buf)
  {
    no_mem_exit("write_out_picture: buf");
  }

  if(rgb_output)
  {
    crop_left   = p->frame_cropping_rect_left_offset;
    crop_right  = p->frame_cropping_rect_right_offset;
    crop_top    = ( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_top_offset;
    crop_bottom = ( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_bottom_offset;

    img2buf (p->imgUV[1], buf, p->size_x_cr, p->size_y_cr, symbol_size_in_bytes, crop_left, crop_right, crop_top, crop_bottom);
    write(p_out, buf, (p->size_y_cr-crop_bottom-crop_top)*(p->size_x_cr-crop_right-crop_left)*symbol_size_in_bytes);

    if (active_sps->frame_cropping_flag)
    {
      crop_left   = SubWidthC[p->chroma_format_idc] * p->frame_cropping_rect_left_offset;
      crop_right  = SubWidthC[p->chroma_format_idc] * p->frame_cropping_rect_right_offset;
      crop_top    = SubHeightC[p->chroma_format_idc]*( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_top_offset;
      crop_bottom = SubHeightC[p->chroma_format_idc]*( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_bottom_offset;
    }
    else
    {
      crop_left = crop_right = crop_top = crop_bottom = 0;
    }
  }

  img2buf (p->imgY, buf, p->size_x, p->size_y, symbol_size_in_bytes, crop_left, crop_right, crop_top, crop_bottom);
  write(p_out, buf, (p->size_y-crop_bottom-crop_top)*(p->size_x-crop_right-crop_left)*symbol_size_in_bytes);

  if (p->chroma_format_idc!=YUV400)
  {
    crop_left   = p->frame_cropping_rect_left_offset;
    crop_right  = p->frame_cropping_rect_right_offset;
    crop_top    = ( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_top_offset;
    crop_bottom = ( 2 - p->frame_mbs_only_flag ) * p->frame_cropping_rect_bottom_offset;

    img2buf (p->imgUV[0], buf, p->size_x_cr, p->size_y_cr, symbol_size_in_bytes, crop_left, crop_right, crop_top, crop_bottom);
    write(p_out, buf, (p->size_y_cr-crop_bottom-crop_top)*(p->size_x_cr-crop_right-crop_left)* symbol_size_in_bytes);

    if (!rgb_output)
    {
      img2buf (p->imgUV[1], buf, p->size_x_cr, p->size_y_cr, symbol_size_in_bytes, crop_left, crop_right, crop_top, crop_bottom);
      write(p_out, buf, (p->size_y_cr-crop_bottom-crop_top)*(p->size_x_cr-crop_right-crop_left)*symbol_size_in_bytes);
    }
  }

  free(buf);
    
//  fsync(p_out);
}

/*!
 ************************************************************************
 * \brief
 *    Initialize output buffer for direct output
 ************************************************************************
 */
void init_out_buffer()
{
  out_buffer = alloc_frame_store();
}

/*!
 ************************************************************************
 * \brief
 *    Uninitialize output buffer for direct output
 ************************************************************************
 */
void uninit_out_buffer()
{
  free_frame_store(out_buffer);
  out_buffer=NULL;
}

/*!
 ************************************************************************
 * \brief
 *    Initialize picture memory with (Y:0,U:128,V:128)
 ************************************************************************
 */
void clear_picture(StorablePicture *p)
{
  int i;

  for(i=0;i<p->size_y;i++)
    memset(p->imgY[i], img->dc_pred_value, p->size_x*sizeof(imgpel));
  for(i=0;i<p->size_y_cr;i++)
    memset(p->imgUV[0][i], img->dc_pred_value, p->size_x_cr*sizeof(imgpel));
  for(i=0;i<p->size_y_cr;i++)
    memset(p->imgUV[1][i], img->dc_pred_value, p->size_x_cr*sizeof(imgpel));
}

/*!
 ************************************************************************
 * \brief
 *    Write out not paired direct output fields. A second empty field is generated
 *    and combined into the frame buffer.
 * \param fs
 *    FrameStore that contains a single field
 * \param p_out
 *    Output file
 ************************************************************************
 */
void write_unpaired_field(FrameStore* fs, int p_out)
{
  StorablePicture *p;
  assert (fs->is_used<3);
  if(fs->is_used &1)
  {
    // we have a top field
    // construct an empty bottom field
    p = fs->top_field;
    fs->bottom_field = alloc_storable_picture(BOTTOM_FIELD, p->size_x, p->size_y, p->size_x_cr, p->size_y_cr);
    fs->bottom_field->chroma_format_idc = p->chroma_format_idc;
    clear_picture(fs->bottom_field);
    dpb_combine_field_yuv(fs);
    write_picture (fs->frame, p_out, TOP_FIELD);
  }

  if(fs->is_used &2)
  {
    // we have a bottom field
    // construct an empty top field
    p = fs->bottom_field;
    fs->top_field = alloc_storable_picture(TOP_FIELD, p->size_x, p->size_y, p->size_x_cr, p->size_y_cr);
    clear_picture(fs->top_field);
    fs->top_field->chroma_format_idc = p->chroma_format_idc;
    clear_picture(fs->top_field);
    fs ->top_field->frame_cropping_flag = fs->bottom_field->frame_cropping_flag;
    if(fs ->top_field->frame_cropping_flag) 
    {
      fs ->top_field->frame_cropping_rect_top_offset = fs->bottom_field->frame_cropping_rect_top_offset;
      fs ->top_field->frame_cropping_rect_bottom_offset = fs->bottom_field->frame_cropping_rect_bottom_offset;
      fs ->top_field->frame_cropping_rect_left_offset = fs->bottom_field->frame_cropping_rect_left_offset;
      fs ->top_field->frame_cropping_rect_right_offset = fs->bottom_field->frame_cropping_rect_right_offset;
    }
    dpb_combine_field_yuv(fs);
    write_picture (fs->frame, p_out, BOTTOM_FIELD);
  }

  fs->is_used=3;
}

/*!
 ************************************************************************
 * \brief
 *    Write out unpaired fields from output buffer.
 * \param p_out
 *    Output file
 ************************************************************************
 */
void flush_direct_output(int p_out)
{
  write_unpaired_field(out_buffer, p_out);

  free_storable_picture(out_buffer->frame);
  out_buffer->frame = NULL;
  free_storable_picture(out_buffer->top_field);
  out_buffer->top_field = NULL;
  free_storable_picture(out_buffer->bottom_field);
  out_buffer->bottom_field = NULL;
  out_buffer->is_used = 0;
}


/*!
 ************************************************************************
 * \brief
 *    Write a frame (from FrameStore)
 * \param fs
 *    FrameStore containing the frame
 * \param p_out
 *    Output file
 ************************************************************************
 */
void write_stored_frame( FrameStore *fs,int p_out)
{
  // make sure no direct output field is pending
  flush_direct_output(p_out);

  if (fs->is_used<3)
  {
    write_unpaired_field(fs, p_out);
  }
  else
  {
    write_picture(fs->frame, p_out, FRAME);
  }

  fs->is_output = 1;
}

/*!
 ************************************************************************
 * \brief
 *    Directly output a picture without storing it in the DPB. Fields 
 *    are buffered before they are written to the file.
 * \param p
 *    Picture for output
 * \param p_out
 *    Output file
 ************************************************************************
 */
void direct_output(StorablePicture *p, int p_out)
{
  if (p->structure==FRAME)
  {
    // we have a frame (or complementary field pair)
    // so output it directly
    flush_direct_output(p_out);
    write_picture (p, p_out, FRAME);
    free_storable_picture(p);
    return;
  }

  if (p->structure == TOP_FIELD)
  {
    if (out_buffer->is_used &1)
      flush_direct_output(p_out);
    out_buffer->top_field = p;
    out_buffer->is_used |= 1;
  }

  if (p->structure == BOTTOM_FIELD)
  {
    if (out_buffer->is_used &2)
      flush_direct_output(p_out);
    out_buffer->bottom_field = p;
    out_buffer->is_used |= 2;
  }

  if (out_buffer->is_used == 3)
  {
    // we have both fields, so output them
    dpb_combine_field_yuv(out_buffer);
    write_picture (out_buffer->frame, p_out, FRAME);
    free_storable_picture(out_buffer->frame);
    out_buffer->frame = NULL;
    free_storable_picture(out_buffer->top_field);
    out_buffer->top_field = NULL;
    free_storable_picture(out_buffer->bottom_field);
    out_buffer->bottom_field = NULL;
    out_buffer->is_used = 0;
  }
}

