kc3-lang/libjpeg-turbo/jdcolext.c

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• Hash : 19c791cd
  Author :
  Date : 2018-03-08T10:55:20
  

  Improve code formatting consistency
  
  With rare exceptions ...
  - Always separate line continuation characters by one space from
    preceding code.
  - Always use two-space indentation.  Never use tabs.
  - Always use K&R-style conditional blocks.
  - Always surround operators with spaces, except in raw assembly code.
  - Always put a space after, but not before, a comma.
  - Never put a space between type casts and variables/function calls.
  - Never put a space between the function name and the argument list in
    function declarations and prototypes.
  - Always surround braces ('{' and '}') with spaces.
  - Always surround statements (if, for, else, catch, while, do, switch)
    with spaces.
  - Always attach pointer symbols ('*' and '**') to the variable or
    function name.
  - Always precede pointer symbols ('*' and '**') by a space in type
    casts.
  - Use the MIN() macro from jpegint.h within the libjpeg and TurboJPEG
    API libraries (using min() from tjutil.h is still necessary for
    TJBench.)
  - Where it makes sense (particularly in the TurboJPEG code), put a blank
    line after variable declaration blocks.
  - Always separate statements in one-liners by two spaces.
  
  The purpose of this was to ease maintenance on my part and also to make
  it easier for contributors to figure out how to format patch
  submissions.  This was admittedly confusing (even to me sometimes) when
  we had 3 or 4 different style conventions in the same source tree.  The
  new convention is more consistent with the formatting of other OSS code
  bases.
  
  This commit corrects deviations from the chosen formatting style in the
  libjpeg API code and reformats the TurboJPEG API code such that it
  conforms to the same standard.
  
  NOTES:
  - Although it is no longer necessary for the function name in function
    declarations to begin in Column 1 (this was historically necessary
    because of the ansi2knr utility, which allowed libjpeg to be built
    with non-ANSI compilers), we retain that formatting for the libjpeg
    code because it improves readability when using libjpeg's function
    attribute macros (GLOBAL(), etc.)
  - This reformatting project was accomplished with the help of AStyle and
    Uncrustify, although neither was completely up to the task, and thus
    a great deal of manual tweaking was required.  Note to developers of
    code formatting utilities:  the libjpeg-turbo code base is an
    excellent test bed, because AFAICT, it breaks every single one of the
    utilities that are currently available.
  - The legacy (MMX, SSE, 3DNow!) assembly code for i386 has been
    formatted to match the SSE2 code (refer to
    ff5685d5344273df321eb63a005eaae19d2496e3.)  I hadn't intended to
    bother with this, but the Loongson MMI implementation demonstrated
    that there is still academic value to the MMX implementation, as an
    algorithmic model for other 64-bit vector implementations.  Thus, it
    is desirable to improve its readability in the same manner as that of
    the SSE2 implementation.
  

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• jdcolext.c

• /*
   * jdcolext.c
   *
   * This file was part of the Independent JPEG Group's software:
   * Copyright (C) 1991-1997, Thomas G. Lane.
   * libjpeg-turbo Modifications:
   * Copyright (C) 2009, 2011, 2015, D. R. Commander.
   * For conditions of distribution and use, see the accompanying README.ijg
   * file.
   *
   * This file contains output colorspace conversion routines.
   */
  
  
  /* This file is included by jdcolor.c */
  
  
  /*
   * Convert some rows of samples to the output colorspace.
   *
   * Note that we change from noninterleaved, one-plane-per-component format
   * to interleaved-pixel format.  The output buffer is therefore three times
   * as wide as the input buffer.
   * A starting row offset is provided only for the input buffer.  The caller
   * can easily adjust the passed output_buf value to accommodate any row
   * offset required on that side.
   */
  
  INLINE
  LOCAL(void)
  ycc_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                           JDIMENSION input_row, JSAMPARRAY output_buf,
                           int num_rows)
  {
    my_cconvert_ptr cconvert = (my_cconvert_ptr)cinfo->cconvert;
    register int y, cb, cr;
    register JSAMPROW outptr;
    register JSAMPROW inptr0, inptr1, inptr2;
    register JDIMENSION col;
    JDIMENSION num_cols = cinfo->output_width;
    /* copy these pointers into registers if possible */
    register JSAMPLE *range_limit = cinfo->sample_range_limit;
    register int *Crrtab = cconvert->Cr_r_tab;
    register int *Cbbtab = cconvert->Cb_b_tab;
    register JLONG *Crgtab = cconvert->Cr_g_tab;
    register JLONG *Cbgtab = cconvert->Cb_g_tab;
    SHIFT_TEMPS
  
    while (--num_rows >= 0) {
      inptr0 = input_buf[0][input_row];
      inptr1 = input_buf[1][input_row];
      inptr2 = input_buf[2][input_row];
      input_row++;
      outptr = *output_buf++;
      for (col = 0; col < num_cols; col++) {
        y  = GETJSAMPLE(inptr0[col]);
        cb = GETJSAMPLE(inptr1[col]);
        cr = GETJSAMPLE(inptr2[col]);
        /* Range-limiting is essential due to noise introduced by DCT losses. */
        outptr[RGB_RED] =   range_limit[y + Crrtab[cr]];
        outptr[RGB_GREEN] = range_limit[y +
                                ((int)RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],
                                                  SCALEBITS))];
        outptr[RGB_BLUE] =  range_limit[y + Cbbtab[cb]];
        /* Set unused byte to 0xFF so it can be interpreted as an opaque */
        /* alpha channel value */
  #ifdef RGB_ALPHA
        outptr[RGB_ALPHA] = 0xFF;
  #endif
        outptr += RGB_PIXELSIZE;
      }
    }
  }
  
  
  /*
   * Convert grayscale to RGB: just duplicate the graylevel three times.
   * This is provided to support applications that don't want to cope
   * with grayscale as a separate case.
   */
  
  INLINE
  LOCAL(void)
  gray_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                            JDIMENSION input_row, JSAMPARRAY output_buf,
                            int num_rows)
  {
    register JSAMPROW inptr, outptr;
    register JDIMENSION col;
    JDIMENSION num_cols = cinfo->output_width;
  
    while (--num_rows >= 0) {
      inptr = input_buf[0][input_row++];
      outptr = *output_buf++;
      for (col = 0; col < num_cols; col++) {
        /* We can dispense with GETJSAMPLE() here */
        outptr[RGB_RED] = outptr[RGB_GREEN] = outptr[RGB_BLUE] = inptr[col];
        /* Set unused byte to 0xFF so it can be interpreted as an opaque */
        /* alpha channel value */
  #ifdef RGB_ALPHA
        outptr[RGB_ALPHA] = 0xFF;
  #endif
        outptr += RGB_PIXELSIZE;
      }
    }
  }
  
  
  /*
   * Convert RGB to extended RGB: just swap the order of source pixels
   */
  
  INLINE
  LOCAL(void)
  rgb_rgb_convert_internal(j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                           JDIMENSION input_row, JSAMPARRAY output_buf,
                           int num_rows)
  {
    register JSAMPROW inptr0, inptr1, inptr2;
    register JSAMPROW outptr;
    register JDIMENSION col;
    JDIMENSION num_cols = cinfo->output_width;
  
    while (--num_rows >= 0) {
      inptr0 = input_buf[0][input_row];
      inptr1 = input_buf[1][input_row];
      inptr2 = input_buf[2][input_row];
      input_row++;
      outptr = *output_buf++;
      for (col = 0; col < num_cols; col++) {
        /* We can dispense with GETJSAMPLE() here */
        outptr[RGB_RED] = inptr0[col];
        outptr[RGB_GREEN] = inptr1[col];
        outptr[RGB_BLUE] = inptr2[col];
        /* Set unused byte to 0xFF so it can be interpreted as an opaque */
        /* alpha channel value */
  #ifdef RGB_ALPHA
        outptr[RGB_ALPHA] = 0xFF;
  #endif
        outptr += RGB_PIXELSIZE;
      }
    }
  }
  

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