/*

 * 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;

    }

  }

}