Index: third_party/libjpeg_turbo/jutils.c |
=================================================================== |
--- third_party/libjpeg_turbo/jutils.c (revision 0) |
+++ third_party/libjpeg_turbo/jutils.c (revision 0) |
@@ -0,0 +1,179 @@ |
+/* |
+ * jutils.c |
+ * |
+ * Copyright (C) 1991-1996, 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 tables and miscellaneous utility routines needed |
+ * for both compression and decompression. |
+ * Note we prefix all global names with "j" to minimize conflicts with |
+ * a surrounding application. |
+ */ |
+ |
+#define JPEG_INTERNALS |
+#include "jinclude.h" |
+#include "jpeglib.h" |
+ |
+ |
+/* |
+ * jpeg_zigzag_order[i] is the zigzag-order position of the i'th element |
+ * of a DCT block read in natural order (left to right, top to bottom). |
+ */ |
+ |
+#if 0 /* This table is not actually needed in v6a */ |
+ |
+const int jpeg_zigzag_order[DCTSIZE2] = { |
+ 0, 1, 5, 6, 14, 15, 27, 28, |
+ 2, 4, 7, 13, 16, 26, 29, 42, |
+ 3, 8, 12, 17, 25, 30, 41, 43, |
+ 9, 11, 18, 24, 31, 40, 44, 53, |
+ 10, 19, 23, 32, 39, 45, 52, 54, |
+ 20, 22, 33, 38, 46, 51, 55, 60, |
+ 21, 34, 37, 47, 50, 56, 59, 61, |
+ 35, 36, 48, 49, 57, 58, 62, 63 |
+}; |
+ |
+#endif |
+ |
+/* |
+ * jpeg_natural_order[i] is the natural-order position of the i'th element |
+ * of zigzag order. |
+ * |
+ * When reading corrupted data, the Huffman decoders could attempt |
+ * to reference an entry beyond the end of this array (if the decoded |
+ * zero run length reaches past the end of the block). To prevent |
+ * wild stores without adding an inner-loop test, we put some extra |
+ * "63"s after the real entries. This will cause the extra coefficient |
+ * to be stored in location 63 of the block, not somewhere random. |
+ * The worst case would be a run-length of 15, which means we need 16 |
+ * fake entries. |
+ */ |
+ |
+const int jpeg_natural_order[DCTSIZE2+16] = { |
+ 0, 1, 8, 16, 9, 2, 3, 10, |
+ 17, 24, 32, 25, 18, 11, 4, 5, |
+ 12, 19, 26, 33, 40, 48, 41, 34, |
+ 27, 20, 13, 6, 7, 14, 21, 28, |
+ 35, 42, 49, 56, 57, 50, 43, 36, |
+ 29, 22, 15, 23, 30, 37, 44, 51, |
+ 58, 59, 52, 45, 38, 31, 39, 46, |
+ 53, 60, 61, 54, 47, 55, 62, 63, |
+ 63, 63, 63, 63, 63, 63, 63, 63, /* extra entries for safety in decoder */ |
+ 63, 63, 63, 63, 63, 63, 63, 63 |
+}; |
+ |
+ |
+/* |
+ * Arithmetic utilities |
+ */ |
+ |
+GLOBAL(long) |
+jdiv_round_up (long a, long b) |
+/* Compute a/b rounded up to next integer, ie, ceil(a/b) */ |
+/* Assumes a >= 0, b > 0 */ |
+{ |
+ return (a + b - 1L) / b; |
+} |
+ |
+ |
+GLOBAL(size_t) |
+jround_up (size_t a, size_t b) |
+/* Compute a rounded up to next multiple of b, ie, ceil(a/b)*b */ |
+/* Assumes a >= 0, b > 0 */ |
+{ |
+ a += b - 1L; |
+ return a - (a % b); |
+} |
+ |
+ |
+/* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays |
+ * and coefficient-block arrays. This won't work on 80x86 because the arrays |
+ * are FAR and we're assuming a small-pointer memory model. However, some |
+ * DOS compilers provide far-pointer versions of memcpy() and memset() even |
+ * in the small-model libraries. These will be used if USE_FMEM is defined. |
+ * Otherwise, the routines below do it the hard way. (The performance cost |
+ * is not all that great, because these routines aren't very heavily used.) |
+ */ |
+ |
+#ifndef NEED_FAR_POINTERS /* normal case, same as regular macros */ |
+#define FMEMCOPY(dest,src,size) MEMCOPY(dest,src,size) |
+#define FMEMZERO(target,size) MEMZERO(target,size) |
+#else /* 80x86 case, define if we can */ |
+#ifdef USE_FMEM |
+#define FMEMCOPY(dest,src,size) _fmemcpy((void FAR *)(dest), (const void FAR *)(src), (size_t)(size)) |
+#define FMEMZERO(target,size) _fmemset((void FAR *)(target), 0, (size_t)(size)) |
+#endif |
+#endif |
+ |
+ |
+GLOBAL(void) |
+jcopy_sample_rows (JSAMPARRAY input_array, int source_row, |
+ JSAMPARRAY output_array, int dest_row, |
+ int num_rows, JDIMENSION num_cols) |
+/* Copy some rows of samples from one place to another. |
+ * num_rows rows are copied from input_array[source_row++] |
+ * to output_array[dest_row++]; these areas may overlap for duplication. |
+ * The source and destination arrays must be at least as wide as num_cols. |
+ */ |
+{ |
+ register JSAMPROW inptr, outptr; |
+#ifdef FMEMCOPY |
+ register size_t count = (size_t) (num_cols * SIZEOF(JSAMPLE)); |
+#else |
+ register JDIMENSION count; |
+#endif |
+ register int row; |
+ |
+ input_array += source_row; |
+ output_array += dest_row; |
+ |
+ for (row = num_rows; row > 0; row--) { |
+ inptr = *input_array++; |
+ outptr = *output_array++; |
+#ifdef FMEMCOPY |
+ FMEMCOPY(outptr, inptr, count); |
+#else |
+ for (count = num_cols; count > 0; count--) |
+ *outptr++ = *inptr++; /* needn't bother with GETJSAMPLE() here */ |
+#endif |
+ } |
+} |
+ |
+ |
+GLOBAL(void) |
+jcopy_block_row (JBLOCKROW input_row, JBLOCKROW output_row, |
+ JDIMENSION num_blocks) |
+/* Copy a row of coefficient blocks from one place to another. */ |
+{ |
+#ifdef FMEMCOPY |
+ FMEMCOPY(output_row, input_row, num_blocks * (DCTSIZE2 * SIZEOF(JCOEF))); |
+#else |
+ register JCOEFPTR inptr, outptr; |
+ register long count; |
+ |
+ inptr = (JCOEFPTR) input_row; |
+ outptr = (JCOEFPTR) output_row; |
+ for (count = (long) num_blocks * DCTSIZE2; count > 0; count--) { |
+ *outptr++ = *inptr++; |
+ } |
+#endif |
+} |
+ |
+ |
+GLOBAL(void) |
+jzero_far (void FAR * target, size_t bytestozero) |
+/* Zero out a chunk of FAR memory. */ |
+/* This might be sample-array data, block-array data, or alloc_large data. */ |
+{ |
+#ifdef FMEMZERO |
+ FMEMZERO(target, bytestozero); |
+#else |
+ register char FAR * ptr = (char FAR *) target; |
+ register size_t count; |
+ |
+ for (count = bytestozero; count > 0; count--) { |
+ *ptr++ = 0; |
+ } |
+#endif |
+} |