text: /*
   * wrbmp.c
   *
   * This file was part of the Independent JPEG Group's software:
   * Copyright (C) 1994-1996, Thomas G. Lane.
   * libjpeg-turbo Modifications:
   * Copyright (C) 2013, Linaro Limited.
   * Copyright (C) 2014, D. R. Commander.
   * For conditions of distribution and use, see the accompanying README file.
   *
   * This file contains routines to write output images in Microsoft "BMP"
   * format (MS Windows 3.x and OS/2 1.x flavors).
   * Either 8-bit colormapped or 24-bit full-color format can be written.
   * No compression is supported.
   *
   * These routines may need modification for non-Unix environments or
   * specialized applications.  As they stand, they assume output to
   * an ordinary stdio stream.
   *
   * This code contributed by James Arthur Boucher.
   */
  
  #include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */
  #include "jconfigint.h"
  
  #ifdef BMP_SUPPORTED
  
  
  /*
   * To support 12-bit JPEG data, we'd have to scale output down to 8 bits.
   * This is not yet implemented.
   */
  
  #if BITS_IN_JSAMPLE != 8
    Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
  #endif
  
  /*
   * Since BMP stores scanlines bottom-to-top, we have to invert the image
   * from JPEG's top-to-bottom order.  To do this, we save the outgoing data
   * in a virtual array during put_pixel_row calls, then actually emit the
   * BMP file during finish_output.  The virtual array contains one JSAMPLE per
   * pixel if the output is grayscale or colormapped, three if it is full color.
   */
  
  /* Private version of data destination object */
  
  typedef struct {
    struct djpeg_dest_struct pub; /* public fields */
  
    boolean is_os2;               /* saves the OS2 format request flag */
  
    jvirt_sarray_ptr whole_image; /* needed to reverse row order */
    JDIMENSION data_width;        /* JSAMPLEs per row */
    JDIMENSION row_width;         /* physical width of one row in the BMP file */
    int pad_bytes;                /* number of padding bytes needed per row */
    JDIMENSION cur_output_row;    /* next row# to write to virtual array */
  } bmp_dest_struct;
  
  typedef bmp_dest_struct * bmp_dest_ptr;
  
  
  /* Forward declarations */
  LOCAL(void) write_colormap
          (j_decompress_ptr cinfo, bmp_dest_ptr dest, int map_colors,
           int map_entry_size);
  
  
  static INLINE boolean is_big_endian(void)
  {
    int test_value = 1;
    if(*(char *)&test_value != 1)
      return TRUE;
    return FALSE;
  }
  
  
  /*
   * Write some pixel data.
   * In this module rows_supplied will always be 1.
   */
  
  METHODDEF(void)
  put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                  JDIMENSION rows_supplied)
  /* This version is for writing 24-bit pixels */
  {
    bmp_dest_ptr dest = (bmp_dest_ptr) dinfo;
    JSAMPARRAY image_ptr;
    register JSAMPROW inptr, outptr;
    register JDIMENSION col;
    int pad;
  
    /* Access next row in virtual array */
    image_ptr = (*cinfo->mem->access_virt_sarray)
      ((j_common_ptr) cinfo, dest->whole_image,
       dest->cur_output_row, (JDIMENSION) 1, TRUE);
    dest->cur_output_row++;
  
    /* Transfer data.  Note destination values must be in BGR order
     * (even though Microsoft's own documents say the opposite).
     */
    inptr = dest->pub.buffer[0];
    outptr = image_ptr[0];
  
    if(cinfo->out_color_space == JCS_RGB565) {
      boolean big_endian = is_big_endian();
      unsigned short *inptr2 = (unsigned short *)inptr;
      for (col = cinfo->output_width; col > 0; col--) {
        if (big_endian) {
          outptr[0] = (*inptr2 >> 5) & 0xF8;
          outptr[1] = ((*inptr2 << 5) & 0xE0) | ((*inptr2 >> 11) & 0x1C);
          outptr[2] = *inptr2 & 0xF8;
        } else {
          outptr[0] = (*inptr2 << 3) & 0xF8;
          outptr[1] = (*inptr2 >> 3) & 0xFC;
          outptr[2] = (*inptr2 >> 8) & 0xF8;
        }
        outptr += 3;
        inptr2++;
      }
    } else {
      for (col = cinfo->output_width; col > 0; col--) {
        outptr[2] = *inptr++;       /* can omit GETJSAMPLE() safely */
        outptr[1] = *inptr++;
        outptr[0] = *inptr++;
        outptr += 3;
      }
    }
  
    /* Zero out the pad bytes. */
    pad = dest->pad_bytes;
    while (--pad >= 0)
      *outptr++ = 0;
  }
  
  METHODDEF(void)
  put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                 JDIMENSION rows_supplied)
  /* This version is for grayscale OR quantized color output */
  {
    bmp_dest_ptr dest = (bmp_dest_ptr) dinfo;
    JSAMPARRAY image_ptr;
    register JSAMPROW inptr, outptr;
    register JDIMENSION col;
    int pad;
  
    /* Access next row in virtual array */
    image_ptr = (*cinfo->mem->access_virt_sarray)
      ((j_common_ptr) cinfo, dest->whole_image,
       dest->cur_output_row, (JDIMENSION) 1, TRUE);
    dest->cur_output_row++;
  
    /* Transfer data. */
    inptr = dest->pub.buffer[0];
    outptr = image_ptr[0];
    for (col = cinfo->output_width; col > 0; col--) {
      *outptr++ = *inptr++;       /* can omit GETJSAMPLE() safely */
    }
  
    /* Zero out the pad bytes. */
    pad = dest->pad_bytes;
    while (--pad >= 0)
      *outptr++ = 0;
  }
  
  
  /*
   * Startup: normally writes the file header.
   * In this module we may as well postpone everything until finish_output.
   */
  
  METHODDEF(void)
  start_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
  {
    /* no work here */
  }
  
  
  /*
   * Finish up at the end of the file.
   *
   * Here is where we really output the BMP file.
   *
   * First, routines to write the Windows and OS/2 variants of the file header.
   */
  
  LOCAL(void)
  write_bmp_header (j_decompress_ptr cinfo, bmp_dest_ptr dest)
  /* Write a Windows-style BMP file header, including colormap if needed */
  {
    char bmpfileheader[14];
    char bmpinfoheader[40];
  #define PUT_2B(array,offset,value)  \
          (array[offset] = (char) ((value) & 0xFF), \
           array[offset+1] = (char) (((value) >> 8) & 0xFF))
  #define PUT_4B(array,offset,value)  \
          (array[offset] = (char) ((value) & 0xFF), \
           array[offset+1] = (char) (((value) >> 8) & 0xFF), \
           array[offset+2] = (char) (((value) >> 16) & 0xFF), \
           array[offset+3] = (char) (((value) >> 24) & 0xFF))
    INT32 headersize, bfSize;
    int bits_per_pixel, cmap_entries;
  
    /* Compute colormap size and total file size */
    if (cinfo->out_color_space == JCS_RGB) {
      if (cinfo->quantize_colors) {
        /* Colormapped RGB */
        bits_per_pixel = 8;
        cmap_entries = 256;
      } else {
        /* Unquantized, full color RGB */
        bits_per_pixel = 24;
        cmap_entries = 0;
      }
    } else if (cinfo->out_color_space == JCS_RGB565) {
      bits_per_pixel = 24;
      cmap_entries   = 0;
    } else {
      /* Grayscale output.  We need to fake a 256-entry colormap. */
      bits_per_pixel = 8;
      cmap_entries = 256;
    }
    /* File size */
    headersize = 14 + 40 + cmap_entries * 4; /* Header and colormap */
    bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height;
  
    /* Set unused fields of header to 0 */
    MEMZERO(bmpfileheader, sizeof(bmpfileheader));
    MEMZERO(bmpinfoheader, sizeof(bmpinfoheader));
  
    /* Fill the file header */
    bmpfileheader[0] = 0x42;      /* first 2 bytes are ASCII 'B', 'M' */
    bmpfileheader[1] = 0x4D;
    PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */
    /* we leave bfReserved1 & bfReserved2 = 0 */
    PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */
  
    /* Fill the info header (Microsoft calls this a BITMAPINFOHEADER) */
    PUT_2B(bmpinfoheader, 0, 40); /* biSize */
    PUT_4B(bmpinfoheader, 4, cinfo->output_width); /* biWidth */
    PUT_4B(bmpinfoheader, 8, cinfo->output_height); /* biHeight */
    PUT_2B(bmpinfoheader, 12, 1); /* biPlanes - must be 1 */
    PUT_2B(bmpinfoheader, 14, bits_per_pixel); /* biBitCount */
    /* we leave biCompression = 0, for none */
    /* we leave biSizeImage = 0; this is correct for uncompressed data */
    if (cinfo->density_unit == 2) { /* if have density in dots/cm, then */
      PUT_4B(bmpinfoheader, 24, (INT32) (cinfo->X_density*100)); /* XPels/M */
      PUT_4B(bmpinfoheader, 28, (INT32) (cinfo->Y_density*100)); /* XPels/M */
    }
    PUT_2B(bmpinfoheader, 32, cmap_entries); /* biClrUsed */
    /* we leave biClrImportant = 0 */
  
    if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14)
      ERREXIT(cinfo, JERR_FILE_WRITE);
    if (JFWRITE(dest->pub.output_file, bmpinfoheader, 40) != (size_t) 40)
      ERREXIT(cinfo, JERR_FILE_WRITE);
  
    if (cmap_entries > 0)
      write_colormap(cinfo, dest, cmap_entries, 4);
  }
  
  
  LOCAL(void)
  write_os2_header (j_decompress_ptr cinfo, bmp_dest_ptr dest)
  /* Write an OS2-style BMP file header, including colormap if needed */
  {
    char bmpfileheader[14];
    char bmpcoreheader[12];
    INT32 headersize, bfSize;
    int bits_per_pixel, cmap_entries;
  
    /* Compute colormap size and total file size */
    if (cinfo->out_color_space == JCS_RGB) {
      if (cinfo->quantize_colors) {
        /* Colormapped RGB */
        bits_per_pixel = 8;
        cmap_entries = 256;
      } else {
        /* Unquantized, full color RGB */
        bits_per_pixel = 24;
        cmap_entries = 0;
      }
    } else if (cinfo->out_color_space == JCS_RGB565) {
      bits_per_pixel = 24;
      cmap_entries   = 0;
    } else {
      /* Grayscale output.  We need to fake a 256-entry colormap. */
      bits_per_pixel = 8;
      cmap_entries = 256;
    }
    /* File size */
    headersize = 14 + 12 + cmap_entries * 3; /* Header and colormap */
    bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height;
  
    /* Set unused fields of header to 0 */
    MEMZERO(bmpfileheader, sizeof(bmpfileheader));
    MEMZERO(bmpcoreheader, sizeof(bmpcoreheader));
  
    /* Fill the file header */
    bmpfileheader[0] = 0x42;      /* first 2 bytes are ASCII 'B', 'M' */
    bmpfileheader[1] = 0x4D;
    PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */
    /* we leave bfReserved1 & bfReserved2 = 0 */
    PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */
  
    /* Fill the info header (Microsoft calls this a BITMAPCOREHEADER) */
    PUT_2B(bmpcoreheader, 0, 12); /* bcSize */
    PUT_2B(bmpcoreheader, 4, cinfo->output_width); /* bcWidth */
    PUT_2B(bmpcoreheader, 6, cinfo->output_height); /* bcHeight */
    PUT_2B(bmpcoreheader, 8, 1);  /* bcPlanes - must be 1 */
    PUT_2B(bmpcoreheader, 10, bits_per_pixel); /* bcBitCount */
  
    if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14)
      ERREXIT(cinfo, JERR_FILE_WRITE);
    if (JFWRITE(dest->pub.output_file, bmpcoreheader, 12) != (size_t) 12)
      ERREXIT(cinfo, JERR_FILE_WRITE);
  
    if (cmap_entries > 0)
      write_colormap(cinfo, dest, cmap_entries, 3);
  }
  
  
  /*
   * Write the colormap.
   * Windows uses BGR0 map entries; OS/2 uses BGR entries.
   */
  
  LOCAL(void)
  write_colormap (j_decompress_ptr cinfo, bmp_dest_ptr dest,
                  int map_colors, int map_entry_size)
  {
    JSAMPARRAY colormap = cinfo->colormap;
    int num_colors = cinfo->actual_number_of_colors;
    FILE * outfile = dest->pub.output_file;
    int i;
  
    if (colormap != NULL) {
      if (cinfo->out_color_components == 3) {
        /* Normal case with RGB colormap */
        for (i = 0; i < num_colors; i++) {
          putc(GETJSAMPLE(colormap[2][i]), outfile);
          putc(GETJSAMPLE(colormap[1][i]), outfile);
          putc(GETJSAMPLE(colormap[0][i]), outfile);
          if (map_entry_size == 4)
            putc(0, outfile);
        }
      } else {
        /* Grayscale colormap (only happens with grayscale quantization) */
        for (i = 0; i < num_colors; i++) {
          putc(GETJSAMPLE(colormap[0][i]), outfile);
          putc(GETJSAMPLE(colormap[0][i]), outfile);
          putc(GETJSAMPLE(colormap[0][i]), outfile);
          if (map_entry_size == 4)
            putc(0, outfile);
        }
      }
    } else {
      /* If no colormap, must be grayscale data.  Generate a linear "map". */
      for (i = 0; i < 256; i++) {
        putc(i, outfile);
        putc(i, outfile);
        putc(i, outfile);
        if (map_entry_size == 4)
          putc(0, outfile);
      }
    }
    /* Pad colormap with zeros to ensure specified number of colormap entries */
    if (i > map_colors)
      ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, i);
    for (; i < map_colors; i++) {
      putc(0, outfile);
      putc(0, outfile);
      putc(0, outfile);
      if (map_entry_size == 4)
        putc(0, outfile);
    }
  }
  
  
  METHODDEF(void)
  finish_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
  {
    bmp_dest_ptr dest = (bmp_dest_ptr) dinfo;
    register FILE * outfile = dest->pub.output_file;
    JSAMPARRAY image_ptr;
    register JSAMPROW data_ptr;
    JDIMENSION row;
    register JDIMENSION col;
    cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
  
    /* Write the header and colormap */
    if (dest->is_os2)
      write_os2_header(cinfo, dest);
    else
      write_bmp_header(cinfo, dest);
  
    /* Write the file body from our virtual array */
    for (row = cinfo->output_height; row > 0; row--) {
      if (progress != NULL) {
        progress->pub.pass_counter = (long) (cinfo->output_height - row);
        progress->pub.pass_limit = (long) cinfo->output_height;
        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
      }
      image_ptr = (*cinfo->mem->access_virt_sarray)
        ((j_common_ptr) cinfo, dest->whole_image, row-1, (JDIMENSION) 1, FALSE);
      data_ptr = image_ptr[0];
      for (col = dest->row_width; col > 0; col--) {
        putc(GETJSAMPLE(*data_ptr), outfile);
        data_ptr++;
      }
    }
    if (progress != NULL)
      progress->completed_extra_passes++;
  
    /* Make sure we wrote the output file OK */
    fflush(outfile);
    if (ferror(outfile))
      ERREXIT(cinfo, JERR_FILE_WRITE);
  }
  
  
  /*
   * The module selection routine for BMP format output.
   */
  
  GLOBAL(djpeg_dest_ptr)
  jinit_write_bmp (j_decompress_ptr cinfo, boolean is_os2)
  {
    bmp_dest_ptr dest;
    JDIMENSION row_width;
  
    /* Create module interface object, fill in method pointers */
    dest = (bmp_dest_ptr)
        (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                    sizeof(bmp_dest_struct));
    dest->pub.start_output = start_output_bmp;
    dest->pub.finish_output = finish_output_bmp;
    dest->is_os2 = is_os2;
  
    if (cinfo->out_color_space == JCS_GRAYSCALE) {
      dest->pub.put_pixel_rows = put_gray_rows;
    } else if (cinfo->out_color_space == JCS_RGB) {
      if (cinfo->quantize_colors)
        dest->pub.put_pixel_rows = put_gray_rows;
      else
        dest->pub.put_pixel_rows = put_pixel_rows;
    } else if(cinfo->out_color_space == JCS_RGB565 ) {
        dest->pub.put_pixel_rows = put_pixel_rows;
    } else {
      ERREXIT(cinfo, JERR_BMP_COLORSPACE);
    }
  
    /* Calculate output image dimensions so we can allocate space */
    jpeg_calc_output_dimensions(cinfo);
  
    /* Determine width of rows in the BMP file (padded to 4-byte boundary). */
    if (cinfo->out_color_space == JCS_RGB565) {
      row_width = cinfo->output_width * 2;
      dest->row_width = dest->data_width = cinfo->output_width * 3;
    } else {
      row_width = cinfo->output_width * cinfo->output_components;
      dest->row_width = dest->data_width = row_width;
    }
    while ((dest->row_width & 3) != 0) dest->row_width++;
    dest->pad_bytes = (int) (dest->row_width - dest->data_width);
    if (cinfo->out_color_space == JCS_RGB565) {
      while ((row_width & 3) != 0) row_width++;
    } else {
      row_width = dest->row_width;
    }
  
  
    /* Allocate space for inversion array, prepare for write pass */
    dest->whole_image = (*cinfo->mem->request_virt_sarray)
      ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
       dest->row_width, cinfo->output_height, (JDIMENSION) 1);
    dest->cur_output_row = 0;
    if (cinfo->progress != NULL) {
      cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
      progress->total_extra_passes++; /* count file input as separate pass */
    }
  
    /* Create decompressor output buffer. */
    dest->pub.buffer = (*cinfo->mem->alloc_sarray)
      ((j_common_ptr) cinfo, JPOOL_IMAGE, row_width, (JDIMENSION) 1);
    dest->pub.buffer_height = 1;
  
    return (djpeg_dest_ptr) dest;
  }
  
  #endif /* BMP_SUPPORTED */
  