Index: third_party/libjpeg/jidctfst.c |
diff --git a/third_party/libjpeg/jidctfst.c b/third_party/libjpeg/jidctfst.c |
deleted file mode 100644 |
index dba4216fb95e7148c24f2d6f6bba8309bb9be24e..0000000000000000000000000000000000000000 |
--- a/third_party/libjpeg/jidctfst.c |
+++ /dev/null |
@@ -1,368 +0,0 @@ |
-/* |
- * jidctfst.c |
- * |
- * Copyright (C) 1994-1998, Thomas G. Lane. |
- * 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 fast, not so accurate integer implementation of the |
- * inverse DCT (Discrete Cosine Transform). In the IJG code, this routine |
- * must also perform dequantization of the input coefficients. |
- * |
- * 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 fixed-point math, |
- * accuracy is lost due to imprecise representation of the scaled |
- * quantization values. The smaller the quantization table entry, the less |
- * precise the scaled value, so this implementation does worse with high- |
- * quality-setting files than with low-quality ones. |
- */ |
- |
-#define JPEG_INTERNALS |
-#include "jinclude.h" |
-#include "jpeglib.h" |
-#include "jdct.h" /* Private declarations for DCT subsystem */ |
- |
-#ifdef DCT_IFAST_SUPPORTED |
- |
- |
-/* |
- * This module is specialized to the case DCTSIZE = 8. |
- */ |
- |
-#if DCTSIZE != 8 |
- Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ |
-#endif |
- |
- |
-/* Scaling decisions are generally the same as in the LL&M algorithm; |
- * see jidctint.c for more details. However, we choose to descale |
- * (right shift) multiplication products as soon as they are formed, |
- * rather than carrying additional fractional bits into subsequent additions. |
- * This compromises accuracy slightly, but it lets us save a few shifts. |
- * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples) |
- * everywhere except in the multiplications proper; this saves a good deal |
- * of work on 16-bit-int machines. |
- * |
- * The dequantized coefficients are not integers because the AA&N scaling |
- * factors have been incorporated. We represent them scaled up by PASS1_BITS, |
- * so that the first and second IDCT rounds have the same input scaling. |
- * For 8-bit JSAMPLEs, we choose IFAST_SCALE_BITS = PASS1_BITS so as to |
- * avoid a descaling shift; this compromises accuracy rather drastically |
- * for small quantization table entries, but it saves a lot of shifts. |
- * For 12-bit JSAMPLEs, there's no hope of using 16x16 multiplies anyway, |
- * so we use a much larger scaling factor to preserve accuracy. |
- * |
- * A final compromise is to represent the multiplicative constants to only |
- * 8 fractional bits, rather than 13. This saves some shifting work on some |
- * machines, and may also reduce the cost of multiplication (since there |
- * are fewer one-bits in the constants). |
- */ |
- |
-#if BITS_IN_JSAMPLE == 8 |
-#define CONST_BITS 8 |
-#define PASS1_BITS 2 |
-#else |
-#define CONST_BITS 8 |
-#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ |
-#endif |
- |
-/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus |
- * causing a lot of useless floating-point operations at run time. |
- * To get around this we use the following pre-calculated constants. |
- * If you change CONST_BITS you may want to add appropriate values. |
- * (With a reasonable C compiler, you can just rely on the FIX() macro...) |
- */ |
- |
-#if CONST_BITS == 8 |
-#define FIX_1_082392200 ((INT32) 277) /* FIX(1.082392200) */ |
-#define FIX_1_414213562 ((INT32) 362) /* FIX(1.414213562) */ |
-#define FIX_1_847759065 ((INT32) 473) /* FIX(1.847759065) */ |
-#define FIX_2_613125930 ((INT32) 669) /* FIX(2.613125930) */ |
-#else |
-#define FIX_1_082392200 FIX(1.082392200) |
-#define FIX_1_414213562 FIX(1.414213562) |
-#define FIX_1_847759065 FIX(1.847759065) |
-#define FIX_2_613125930 FIX(2.613125930) |
-#endif |
- |
- |
-/* We can gain a little more speed, with a further compromise in accuracy, |
- * by omitting the addition in a descaling shift. This yields an incorrectly |
- * rounded result half the time... |
- */ |
- |
-#ifndef USE_ACCURATE_ROUNDING |
-#undef DESCALE |
-#define DESCALE(x,n) RIGHT_SHIFT(x, n) |
-#endif |
- |
- |
-/* Multiply a DCTELEM variable by an INT32 constant, and immediately |
- * descale to yield a DCTELEM result. |
- */ |
- |
-#define MULTIPLY(var,const) ((DCTELEM) DESCALE((var) * (const), CONST_BITS)) |
- |
- |
-/* Dequantize a coefficient by multiplying it by the multiplier-table |
- * entry; produce a DCTELEM result. For 8-bit data a 16x16->16 |
- * multiplication will do. For 12-bit data, the multiplier table is |
- * declared INT32, so a 32-bit multiply will be used. |
- */ |
- |
-#if BITS_IN_JSAMPLE == 8 |
-#define DEQUANTIZE(coef,quantval) (((IFAST_MULT_TYPE) (coef)) * (quantval)) |
-#else |
-#define DEQUANTIZE(coef,quantval) \ |
- DESCALE((coef)*(quantval), IFAST_SCALE_BITS-PASS1_BITS) |
-#endif |
- |
- |
-/* Like DESCALE, but applies to a DCTELEM and produces an int. |
- * We assume that int right shift is unsigned if INT32 right shift is. |
- */ |
- |
-#ifdef RIGHT_SHIFT_IS_UNSIGNED |
-#define ISHIFT_TEMPS DCTELEM ishift_temp; |
-#if BITS_IN_JSAMPLE == 8 |
-#define DCTELEMBITS 16 /* DCTELEM may be 16 or 32 bits */ |
-#else |
-#define DCTELEMBITS 32 /* DCTELEM must be 32 bits */ |
-#endif |
-#define IRIGHT_SHIFT(x,shft) \ |
- ((ishift_temp = (x)) < 0 ? \ |
- (ishift_temp >> (shft)) | ((~((DCTELEM) 0)) << (DCTELEMBITS-(shft))) : \ |
- (ishift_temp >> (shft))) |
-#else |
-#define ISHIFT_TEMPS |
-#define IRIGHT_SHIFT(x,shft) ((x) >> (shft)) |
-#endif |
- |
-#ifdef USE_ACCURATE_ROUNDING |
-#define IDESCALE(x,n) ((int) IRIGHT_SHIFT((x) + (1 << ((n)-1)), n)) |
-#else |
-#define IDESCALE(x,n) ((int) IRIGHT_SHIFT(x, n)) |
-#endif |
- |
- |
-/* |
- * Perform dequantization and inverse DCT on one block of coefficients. |
- */ |
- |
-GLOBAL(void) |
-jpeg_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info * compptr, |
- JCOEFPTR coef_block, |
- JSAMPARRAY output_buf, JDIMENSION output_col) |
-{ |
- DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; |
- DCTELEM tmp10, tmp11, tmp12, tmp13; |
- DCTELEM z5, z10, z11, z12, z13; |
- JCOEFPTR inptr; |
- IFAST_MULT_TYPE * quantptr; |
- int * wsptr; |
- JSAMPROW outptr; |
- JSAMPLE *range_limit = IDCT_range_limit(cinfo); |
- int ctr; |
- int workspace[DCTSIZE2]; /* buffers data between passes */ |
- SHIFT_TEMPS /* for DESCALE */ |
- ISHIFT_TEMPS /* for IDESCALE */ |
- |
- /* Pass 1: process columns from input, store into work array. */ |
- |
- inptr = coef_block; |
- quantptr = (IFAST_MULT_TYPE *) compptr->dct_table; |
- wsptr = workspace; |
- for (ctr = DCTSIZE; ctr > 0; ctr--) { |
- /* 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. |
- */ |
- |
- if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 && |
- inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 && |
- inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 && |
- inptr[DCTSIZE*7] == 0) { |
- /* AC terms all zero */ |
- int dcval = (int) DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); |
- |
- wsptr[DCTSIZE*0] = dcval; |
- wsptr[DCTSIZE*1] = dcval; |
- wsptr[DCTSIZE*2] = dcval; |
- wsptr[DCTSIZE*3] = dcval; |
- wsptr[DCTSIZE*4] = dcval; |
- wsptr[DCTSIZE*5] = dcval; |
- wsptr[DCTSIZE*6] = dcval; |
- wsptr[DCTSIZE*7] = dcval; |
- |
- inptr++; /* advance pointers to next column */ |
- quantptr++; |
- wsptr++; |
- continue; |
- } |
- |
- /* Even part */ |
- |
- tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]); |
- tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]); |
- tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]); |
- tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]); |
- |
- tmp10 = tmp0 + tmp2; /* phase 3 */ |
- tmp11 = tmp0 - tmp2; |
- |
- tmp13 = tmp1 + tmp3; /* phases 5-3 */ |
- tmp12 = MULTIPLY(tmp1 - tmp3, FIX_1_414213562) - tmp13; /* 2*c4 */ |
- |
- tmp0 = tmp10 + tmp13; /* phase 2 */ |
- tmp3 = tmp10 - tmp13; |
- tmp1 = tmp11 + tmp12; |
- tmp2 = tmp11 - tmp12; |
- |
- /* Odd part */ |
- |
- tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]); |
- tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]); |
- tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]); |
- tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]); |
- |
- z13 = tmp6 + tmp5; /* phase 6 */ |
- z10 = tmp6 - tmp5; |
- z11 = tmp4 + tmp7; |
- z12 = tmp4 - tmp7; |
- |
- tmp7 = z11 + z13; /* phase 5 */ |
- tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */ |
- |
- z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */ |
- tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ |
- tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */ |
- |
- tmp6 = tmp12 - tmp7; /* phase 2 */ |
- tmp5 = tmp11 - tmp6; |
- tmp4 = tmp10 + tmp5; |
- |
- wsptr[DCTSIZE*0] = (int) (tmp0 + tmp7); |
- wsptr[DCTSIZE*7] = (int) (tmp0 - tmp7); |
- wsptr[DCTSIZE*1] = (int) (tmp1 + tmp6); |
- wsptr[DCTSIZE*6] = (int) (tmp1 - tmp6); |
- wsptr[DCTSIZE*2] = (int) (tmp2 + tmp5); |
- wsptr[DCTSIZE*5] = (int) (tmp2 - tmp5); |
- wsptr[DCTSIZE*4] = (int) (tmp3 + tmp4); |
- wsptr[DCTSIZE*3] = (int) (tmp3 - tmp4); |
- |
- inptr++; /* advance pointers to next column */ |
- quantptr++; |
- wsptr++; |
- } |
- |
- /* Pass 2: process rows from work array, store into output array. */ |
- /* Note that we must descale the results by a factor of 8 == 2**3, */ |
- /* and also undo the PASS1_BITS scaling. */ |
- |
- wsptr = workspace; |
- for (ctr = 0; ctr < DCTSIZE; ctr++) { |
- outptr = output_buf[ctr] + output_col; |
- /* 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). |
- * On machines with very fast multiplication, it's possible that the |
- * test takes more time than it's worth. In that case this section |
- * may be commented out. |
- */ |
- |
-#ifndef NO_ZERO_ROW_TEST |
- if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 && |
- wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) { |
- /* AC terms all zero */ |
- JSAMPLE dcval = range_limit[IDESCALE(wsptr[0], PASS1_BITS+3) |
- & RANGE_MASK]; |
- |
- outptr[0] = dcval; |
- outptr[1] = dcval; |
- outptr[2] = dcval; |
- outptr[3] = dcval; |
- outptr[4] = dcval; |
- outptr[5] = dcval; |
- outptr[6] = dcval; |
- outptr[7] = dcval; |
- |
- wsptr += DCTSIZE; /* advance pointer to next row */ |
- continue; |
- } |
-#endif |
- |
- /* Even part */ |
- |
- tmp10 = ((DCTELEM) wsptr[0] + (DCTELEM) wsptr[4]); |
- tmp11 = ((DCTELEM) wsptr[0] - (DCTELEM) wsptr[4]); |
- |
- tmp13 = ((DCTELEM) wsptr[2] + (DCTELEM) wsptr[6]); |
- tmp12 = MULTIPLY((DCTELEM) wsptr[2] - (DCTELEM) wsptr[6], FIX_1_414213562) |
- - tmp13; |
- |
- tmp0 = tmp10 + tmp13; |
- tmp3 = tmp10 - tmp13; |
- tmp1 = tmp11 + tmp12; |
- tmp2 = tmp11 - tmp12; |
- |
- /* Odd part */ |
- |
- z13 = (DCTELEM) wsptr[5] + (DCTELEM) wsptr[3]; |
- z10 = (DCTELEM) wsptr[5] - (DCTELEM) wsptr[3]; |
- z11 = (DCTELEM) wsptr[1] + (DCTELEM) wsptr[7]; |
- z12 = (DCTELEM) wsptr[1] - (DCTELEM) wsptr[7]; |
- |
- tmp7 = z11 + z13; /* phase 5 */ |
- tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */ |
- |
- z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */ |
- tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */ |
- tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */ |
- |
- tmp6 = tmp12 - tmp7; /* phase 2 */ |
- tmp5 = tmp11 - tmp6; |
- tmp4 = tmp10 + tmp5; |
- |
- /* Final output stage: scale down by a factor of 8 and range-limit */ |
- |
- outptr[0] = range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[7] = range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[1] = range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[6] = range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[2] = range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[5] = range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[4] = range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS+3) |
- & RANGE_MASK]; |
- outptr[3] = range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS+3) |
- & RANGE_MASK]; |
- |
- wsptr += DCTSIZE; /* advance pointer to next row */ |
- } |
-} |
- |
-#endif /* DCT_IFAST_SUPPORTED */ |