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<html><!-- Created using the cpp_pretty_printer from the dlib C++ library. See http://dlib.net for updates. --><head><title>dlib C++ Library - jidctflt.c</title></head><body bgcolor='white'><pre>
<font color='#009900'>/*
* jidctflt.c
*
* Copyright (C) 1994-1998, Thomas G. Lane.
* Modified 2010 by Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains a floating-point implementation of the
* inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
* must also perform dequantization of the input coefficients.
*
* This implementation should be more accurate than either of the integer
* IDCT implementations. However, it may not give the same results on all
* machines because of differences in roundoff behavior. Speed will depend
* on the hardware's floating point capacity.
*
* A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
* on each row (or vice versa, but it's more convenient to emit a row at
* a time). Direct algorithms are also available, but they are much more
* complex and seem not to be any faster when reduced to code.
*
* This implementation is based on Arai, Agui, and Nakajima's algorithm for
* scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in
* Japanese, but the algorithm is described in the Pennebaker & Mitchell
* JPEG textbook (see REFERENCES section in file README). The following code
* is based directly on figure 4-8 in P&M.
* While an 8-point DCT cannot be done in less than 11 multiplies, it is
* possible to arrange the computation so that many of the multiplies are
* simple scalings of the final outputs. These multiplies can then be
* folded into the multiplications or divisions by the JPEG quantization
* table entries. The AA&N method leaves only 5 multiplies and 29 adds
* to be done in the DCT itself.
* The primary disadvantage of this method is that with a fixed-point
* implementation, accuracy is lost due to imprecise representation of the
* scaled quantization values. However, that problem does not arise if
* we use floating point arithmetic.
*/</font>
<font color='#0000FF'>#define</font> JPEG_INTERNALS
<font color='#0000FF'>#include</font> "<a style='text-decoration:none' href='jinclude.h.html'>jinclude.h</a>"
<font color='#0000FF'>#include</font> "<a style='text-decoration:none' href='jpeglib.h.html'>jpeglib.h</a>"
<font color='#0000FF'>#include</font> "<a style='text-decoration:none' href='jdct.h.html'>jdct.h</a>" <font color='#009900'>/* Private declarations for DCT subsystem */</font>
<font color='#0000FF'>#ifdef</font> DCT_FLOAT_SUPPORTED
<font color='#009900'>/*
* This module is specialized to the case DCTSIZE = 8.
*/</font>
<font color='#0000FF'>#if</font> DCTSIZE <font color='#5555FF'>!</font><font color='#5555FF'>=</font> <font color='#979000'>8</font>
Sorry, <font color='#0000FF'>this</font> code only copes with <font color='#979000'>8</font>x8 DCTs. <font color='#009900'>/* deliberate syntax err */</font>
<font color='#0000FF'>#endif</font>
<font color='#009900'>/* Dequantize a coefficient by multiplying it by the multiplier-table
* entry; produce a float result.
*/</font>
<font color='#0000FF'>#define</font> DEQUANTIZE<font face='Lucida Console'>(</font>coef,quantval<font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>coef<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font>quantval<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font>
<font color='#009900'>/*
* Perform dequantization and inverse DCT on one block of coefficients.
*/</font>
<b><a name='GLOBAL'></a>GLOBAL</b><font face='Lucida Console'>(</font><font color='#0000FF'><u>void</u></font><font face='Lucida Console'>)</font>
<b><a name='jpeg_idct_float'></a>jpeg_idct_float</b> <font face='Lucida Console'>(</font>j_decompress_ptr cinfo, jpeg_component_info <font color='#5555FF'>*</font> compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col<font face='Lucida Console'>)</font>
<b>{</b>
FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
FAST_FLOAT tmp10, tmp11, tmp12, tmp13;
FAST_FLOAT z5, z10, z11, z12, z13;
JCOEFPTR inptr;
FLOAT_MULT_TYPE <font color='#5555FF'>*</font> quantptr;
FAST_FLOAT <font color='#5555FF'>*</font> wsptr;
JSAMPROW outptr;
JSAMPLE <font color='#5555FF'>*</font>range_limit <font color='#5555FF'>=</font> cinfo<font color='#5555FF'>-</font><font color='#5555FF'>></font>sample_range_limit;
<font color='#0000FF'><u>int</u></font> ctr;
FAST_FLOAT workspace[DCTSIZE2]; <font color='#009900'>/* buffers data between passes */</font>
<font color='#009900'>/* Pass 1: process columns from input, store into work array. */</font>
inptr <font color='#5555FF'>=</font> coef_block;
quantptr <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>FLOAT_MULT_TYPE <font color='#5555FF'>*</font><font face='Lucida Console'>)</font> compptr<font color='#5555FF'>-</font><font color='#5555FF'>></font>dct_table;
wsptr <font color='#5555FF'>=</font> workspace;
<font color='#0000FF'>for</font> <font face='Lucida Console'>(</font>ctr <font color='#5555FF'>=</font> DCTSIZE; ctr <font color='#5555FF'>></font> <font color='#979000'>0</font>; ctr<font color='#5555FF'>-</font><font color='#5555FF'>-</font><font face='Lucida Console'>)</font> <b>{</b>
<font color='#009900'>/* Due to quantization, we will usually find that many of the input
* coefficients are zero, especially the AC terms. We can exploit this
* by short-circuiting the IDCT calculation for any column in which all
* the AC terms are zero. In that case each output is equal to the
* DC coefficient (with scale factor as needed).
* With typical images and quantization tables, half or more of the
* column DCT calculations can be simplified this way.
*/</font>
<font color='#0000FF'>if</font> <font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>1</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font> inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>2</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font>
inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>3</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font> inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>4</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font>
inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>5</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font> inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>6</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font> <font color='#5555FF'>&</font><font color='#5555FF'>&</font>
inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>7</font>] <font color='#5555FF'>=</font><font color='#5555FF'>=</font> <font color='#979000'>0</font><font face='Lucida Console'>)</font> <b>{</b>
<font color='#009900'>/* AC terms all zero */</font>
FAST_FLOAT dcval <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>]<font face='Lucida Console'>)</font>;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>1</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>2</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>3</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>4</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>5</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>6</font>] <font color='#5555FF'>=</font> dcval;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>7</font>] <font color='#5555FF'>=</font> dcval;
inptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>; <font color='#009900'>/* advance pointers to next column */</font>
quantptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>;
wsptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>;
<font color='#0000FF'>continue</font>;
<b>}</b>
<font color='#009900'>/* Even part */</font>
tmp0 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>]<font face='Lucida Console'>)</font>;
tmp1 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>2</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>2</font>]<font face='Lucida Console'>)</font>;
tmp2 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>4</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>4</font>]<font face='Lucida Console'>)</font>;
tmp3 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>6</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>6</font>]<font face='Lucida Console'>)</font>;
tmp10 <font color='#5555FF'>=</font> tmp0 <font color='#5555FF'>+</font> tmp2; <font color='#009900'>/* phase 3 */</font>
tmp11 <font color='#5555FF'>=</font> tmp0 <font color='#5555FF'>-</font> tmp2;
tmp13 <font color='#5555FF'>=</font> tmp1 <font color='#5555FF'>+</font> tmp3; <font color='#009900'>/* phases 5-3 */</font>
tmp12 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>tmp1 <font color='#5555FF'>-</font> tmp3<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.414213562</font><font face='Lucida Console'>)</font> <font color='#5555FF'>-</font> tmp13; <font color='#009900'>/* 2*c4 */</font>
tmp0 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>+</font> tmp13; <font color='#009900'>/* phase 2 */</font>
tmp3 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>-</font> tmp13;
tmp1 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>+</font> tmp12;
tmp2 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>-</font> tmp12;
<font color='#009900'>/* Odd part */</font>
tmp4 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>1</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>1</font>]<font face='Lucida Console'>)</font>;
tmp5 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>3</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>3</font>]<font face='Lucida Console'>)</font>;
tmp6 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>5</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>5</font>]<font face='Lucida Console'>)</font>;
tmp7 <font color='#5555FF'>=</font> <font color='#BB00BB'>DEQUANTIZE</font><font face='Lucida Console'>(</font>inptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>7</font>], quantptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>7</font>]<font face='Lucida Console'>)</font>;
z13 <font color='#5555FF'>=</font> tmp6 <font color='#5555FF'>+</font> tmp5; <font color='#009900'>/* phase 6 */</font>
z10 <font color='#5555FF'>=</font> tmp6 <font color='#5555FF'>-</font> tmp5;
z11 <font color='#5555FF'>=</font> tmp4 <font color='#5555FF'>+</font> tmp7;
z12 <font color='#5555FF'>=</font> tmp4 <font color='#5555FF'>-</font> tmp7;
tmp7 <font color='#5555FF'>=</font> z11 <font color='#5555FF'>+</font> z13; <font color='#009900'>/* phase 5 */</font>
tmp11 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>z11 <font color='#5555FF'>-</font> z13<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.414213562</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*c4 */</font>
z5 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>z10 <font color='#5555FF'>+</font> z12<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.847759065</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*c2 */</font>
tmp10 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>-</font> z12 <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.082392200</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*(c2-c6) */</font>
tmp12 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>-</font> z10 <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>2.613125930</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*(c2+c6) */</font>
tmp6 <font color='#5555FF'>=</font> tmp12 <font color='#5555FF'>-</font> tmp7; <font color='#009900'>/* phase 2 */</font>
tmp5 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>-</font> tmp6;
tmp4 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>-</font> tmp5;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>0</font>] <font color='#5555FF'>=</font> tmp0 <font color='#5555FF'>+</font> tmp7;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>7</font>] <font color='#5555FF'>=</font> tmp0 <font color='#5555FF'>-</font> tmp7;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>1</font>] <font color='#5555FF'>=</font> tmp1 <font color='#5555FF'>+</font> tmp6;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>6</font>] <font color='#5555FF'>=</font> tmp1 <font color='#5555FF'>-</font> tmp6;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>2</font>] <font color='#5555FF'>=</font> tmp2 <font color='#5555FF'>+</font> tmp5;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>5</font>] <font color='#5555FF'>=</font> tmp2 <font color='#5555FF'>-</font> tmp5;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>3</font>] <font color='#5555FF'>=</font> tmp3 <font color='#5555FF'>+</font> tmp4;
wsptr[DCTSIZE<font color='#5555FF'>*</font><font color='#979000'>4</font>] <font color='#5555FF'>=</font> tmp3 <font color='#5555FF'>-</font> tmp4;
inptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>; <font color='#009900'>/* advance pointers to next column */</font>
quantptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>;
wsptr<font color='#5555FF'>+</font><font color='#5555FF'>+</font>;
<b>}</b>
<font color='#009900'>/* Pass 2: process rows from work array, store into output array. */</font>
wsptr <font color='#5555FF'>=</font> workspace;
<font color='#0000FF'>for</font> <font face='Lucida Console'>(</font>ctr <font color='#5555FF'>=</font> <font color='#979000'>0</font>; ctr <font color='#5555FF'><</font> DCTSIZE; ctr<font color='#5555FF'>+</font><font color='#5555FF'>+</font><font face='Lucida Console'>)</font> <b>{</b>
outptr <font color='#5555FF'>=</font> output_buf[ctr] <font color='#5555FF'>+</font> output_col;
<font color='#009900'>/* Rows of zeroes can be exploited in the same way as we did with columns.
* However, the column calculation has created many nonzero AC terms, so
* the simplification applies less often (typically 5% to 10% of the time).
* And testing floats for zero is relatively expensive, so we don't bother.
*/</font>
<font color='#009900'>/* Even part */</font>
<font color='#009900'>/* Apply signed->unsigned and prepare float->int conversion */</font>
z5 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>0</font>] <font color='#5555FF'>+</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> CENTERJSAMPLE <font color='#5555FF'>+</font> <font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>0.5</font><font face='Lucida Console'>)</font>;
tmp10 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>+</font> wsptr[<font color='#979000'>4</font>];
tmp11 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>-</font> wsptr[<font color='#979000'>4</font>];
tmp13 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>2</font>] <font color='#5555FF'>+</font> wsptr[<font color='#979000'>6</font>];
tmp12 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>wsptr[<font color='#979000'>2</font>] <font color='#5555FF'>-</font> wsptr[<font color='#979000'>6</font>]<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.414213562</font><font face='Lucida Console'>)</font> <font color='#5555FF'>-</font> tmp13;
tmp0 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>+</font> tmp13;
tmp3 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>-</font> tmp13;
tmp1 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>+</font> tmp12;
tmp2 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>-</font> tmp12;
<font color='#009900'>/* Odd part */</font>
z13 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>5</font>] <font color='#5555FF'>+</font> wsptr[<font color='#979000'>3</font>];
z10 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>5</font>] <font color='#5555FF'>-</font> wsptr[<font color='#979000'>3</font>];
z11 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>1</font>] <font color='#5555FF'>+</font> wsptr[<font color='#979000'>7</font>];
z12 <font color='#5555FF'>=</font> wsptr[<font color='#979000'>1</font>] <font color='#5555FF'>-</font> wsptr[<font color='#979000'>7</font>];
tmp7 <font color='#5555FF'>=</font> z11 <font color='#5555FF'>+</font> z13;
tmp11 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>z11 <font color='#5555FF'>-</font> z13<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.414213562</font><font face='Lucida Console'>)</font>;
z5 <font color='#5555FF'>=</font> <font face='Lucida Console'>(</font>z10 <font color='#5555FF'>+</font> z12<font face='Lucida Console'>)</font> <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.847759065</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*c2 */</font>
tmp10 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>-</font> z12 <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>1.082392200</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*(c2-c6) */</font>
tmp12 <font color='#5555FF'>=</font> z5 <font color='#5555FF'>-</font> z10 <font color='#5555FF'>*</font> <font face='Lucida Console'>(</font><font face='Lucida Console'>(</font>FAST_FLOAT<font face='Lucida Console'>)</font> <font color='#979000'>2.613125930</font><font face='Lucida Console'>)</font>; <font color='#009900'>/* 2*(c2+c6) */</font>
tmp6 <font color='#5555FF'>=</font> tmp12 <font color='#5555FF'>-</font> tmp7;
tmp5 <font color='#5555FF'>=</font> tmp11 <font color='#5555FF'>-</font> tmp6;
tmp4 <font color='#5555FF'>=</font> tmp10 <font color='#5555FF'>-</font> tmp5;
<font color='#009900'>/* Final output stage: float->int conversion and range-limit */</font>
outptr[<font color='#979000'>0</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp0 <font color='#5555FF'>+</font> tmp7<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>7</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp0 <font color='#5555FF'>-</font> tmp7<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>1</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp1 <font color='#5555FF'>+</font> tmp6<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>6</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp1 <font color='#5555FF'>-</font> tmp6<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>2</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp2 <font color='#5555FF'>+</font> tmp5<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>5</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp2 <font color='#5555FF'>-</font> tmp5<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>3</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp3 <font color='#5555FF'>+</font> tmp4<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
outptr[<font color='#979000'>4</font>] <font color='#5555FF'>=</font> range_limit[<font face='Lucida Console'>(</font><font face='Lucida Console'>(</font><font color='#0000FF'><u>int</u></font><font face='Lucida Console'>)</font> <font face='Lucida Console'>(</font>tmp3 <font color='#5555FF'>-</font> tmp4<font face='Lucida Console'>)</font><font face='Lucida Console'>)</font> <font color='#5555FF'>&</font> RANGE_MASK];
wsptr <font color='#5555FF'>+</font><font color='#5555FF'>=</font> DCTSIZE; <font color='#009900'>/* advance pointer to next row */</font>
<b>}</b>
<b>}</b>
<font color='#0000FF'>#endif</font> <font color='#009900'>/* DCT_FLOAT_SUPPORTED */</font>
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